SUFERFUND RECORDS CTRo W J A

POST-REMOVAL SITE CONTROL PLANSACO MUNICIPAL LANDFILL

WOODARDampCURRANEngineering bull Science bull Operations41 Hutchins DrivePortland ME 04102Tel (207) 774-21 12Date March 1999

06401

Table of Contents

1 Introduction amp General Information bull 1

2 Record Keeping and Reporting 1

3 Normal Operations and Maintenance 2

4 Operational Safety Plan 4

5 Evaluation of Vegetative Growth Erosion and Other Site Conditions 4

6 Assessment of Erosion Controls and Stormwater Management Basin 5

7 Potential Problems and Contingency Plan 6

8 Evaluation of Stability 7

9 Assessment of Passive Gas Venting System 7

10 Evaluation of Sandy Brook Sediment Removal Area 8

11 Impact on Wetlands 8

12 Settlement Monitoring 8

Outline of Sample Progress Report

Figures

1 Area Site Plan (reduced Record Drawing sheet 2 of 11)

2 As-Built Grading Plan (reduced Record Drawing sheet 5A of 11)

Forms

Maintenance Record Form Significant Weather Event Form Inspection Record Form

9606401 - i - March 26 1999

1 INTRODUCTION amp GENERAL INFORMATION

This Post Removal Site Control (PRSC) Plan has been prepared in accordance with the Administrative Order of Consent (Order) (US Environmental Protection Agency [USEPA] Comprehensive Environmental Response Compensation and Liability Act [CERCLA] Docket No I-CERCLA-95-1069) and Appendix B (Non-Time Critical Removal Statement of Work) to the Order for the Saco Municipal Landfill (SML) Superfund site This document is one of six deliverable documents that are required under Article V of Appendix B This PRSC Plan applies primarily to the multi-layer cap that is constructed on Landfill Areas 3 and 4 and the specific incidental features identified in this Plan The PRSC activities shall be conducted for 30 years after the completion of the NTCRA unless otherwise approved by the EPA The overall site features (prior to project construction) are shown on the Area Site Plan from the Project Record Drawings a copy of which is attached to this PRSC Plan

The purpose of the PRSC Plan is to define those operation and maintenance activities that will be performed to maintain the landfill cap and associated drainage systems The objective of the landfill cap and drainage systems is to prevent infiltration of water into the waste within the landfill and control the drainage of water on and away from the cap in a manner that does not cause erosion of the cover or drainage systems or allow sediment to flow into Sandy Brook By performing the maintenance and monitoring activities in a timely manner as outlined in this Plan the potential for major repairs and longshyterm costs will be reduced

The cover system cap on Landfill Areas 3 and 4 covers an area of approximately 13 acres The cover system was designed to meet the performance requirements of the Resource Conservation and Recovery Act (RCRA) Subtitle C regulations and existing requirements of the Maine DEP and US EPA The cover system consists (from the bottom) of a base soil layer 9 inches of gas collection sand 24 inches of low-permeability soil (clay) a synthetic LLDPE 60 mil textured geomembrane 12 inches of drainage sand a geotextile fabric 12 to 18 inches of select borrow soil and 6 inches of topsoil with an erosion control blanket to control erosion before the vegetative grass cover becomes established The cover system also includes 20 passive gas vents surface water diversion benches perimeter ditches culverts and a stormwater management basin

The project was constructed as documented in the Final Completion of Removal Action Report which includes the record drawings the project specifications and the Construction Quality Assurance Plan These documents should be consulted for detailed information about the constructed systems Any work performed on the landfill site as described in this plan shall be performed under the direction of a City representative who is thoroughly familiar with this PRSC Plan the Completion of Removal Action Report and the Long-Term Monitoring Plan An archive copy of these three documents shall be maintained by the City of Saco and a working copy of the documents should be possessed by the City representative(s) who are responsible for the site operation and maintenance

2 RECORD KEEPING AND REPORTING

The PRSC activities shall be initiated upon completion of construction of the NTCRA Progress reports shall be submitted to the EPA and the Maine DEP throughout the period of the PRSC as described in this Plan and shall address each of the items that are identified in this Plan They will identify all of the

9606401 1 032699

PRSC activities that were performed since the previous PRSC Progress Report and those activities that will be performed in the time period until the next PRSC Progress Report The reports shall also include a summary of the results of any PRSC tests or evaluations completed since the last report and they shall identify any corrective measures that have been or need to be completed

Progress Reports shall be submitted three times per year for the first two years following approval of the PRSC Plan by EPA in June September and December for inspections conducted the previous month Inspections will be performed by a qualified Professional Engineer using the attached Inspection Record Form to ensure that all inspection items are addressed For the next eight years the PRSC Progress Reports shall be submitted in June and November of each year Thereafter Progress Reports shall be submitted annually in November

The site shall also be inspected after each significant weather event during the first two years of the post-removal monitoring program or for six months after a major re-vegetation activity (exceeding an area of 10000 square feet) A significant weather event is defined as 1-inch or more of rainfall in a 24 hour period The inspection may be performed by a qualified representative of the City of Saco and shall be documented on the Significant Weather Event form attached to this Plan If erosion is observed or if sediment containing run-off is entering Sandy Brook the US EPA and Maine DEP shall be notified immediately

Contact names addresses and phone numbers for reporting and emergency notification are as follows

Mr Edward Hathaway Mr Wilkes Harper USEPA Region 1 Maine Department of Environmental Protection 1 Congress Street Bureau of Remediation Suite 1100 (Mail code HBT) State House Station 17 Boston MA 02203-2211 Augusta ME 04333-0017 Phone 617-918-1372 Phoneshy 207-287-2651 Fax 617-918-1291 Fax 207-287-7826 Emergency ONLY (for uncontrolled releases spills Emergency Response ONLY (for uncontrolled or fires) 1-800-424-8802 releases spills or fires)- 1-800-482-0777

3 NORMAL OPERATIONS AND MAINTENANCE

Normal operations and maintenance for this site will consist primarily of landscaping care and site inspections The purpose of the maintenance program is to identify and correct any damage that may occur to the engineered systems at the site either by natural causes or by vandalism that could interfere with the proper functioning of these systems If damage is identified the cause of the damage shall be investigated and corrective maintenance or repairs shall be implemented

It is important to maintain and inspect the site so as to prevent more serious problems The grass must be mowed annually in order to prevent the growth of woody vegetation which could damage the cover system Erosion of soils could result in clogged drainage systems or exposure of the underlying geotextile or the geomembrane layers It is important that all drainage systems are operating properly in

9606401 2 OV2699

order to prevent saturation of soils Saturated soils are the most likely cause of slope failure resulting in expensive repairs and possible environmental damage

The normal landscaping care will include grass mowing drainage system cleaning and related maintenance Typical maintenance could include the repair of eroded soil or damaged drainage systems This work shall be the responsibility of the City of Saco In order to reduce potential impact to nesting birds the grass should be mowed only after July 15 each year The cut grass may either be left m place as mulch or removed Any thick deposits of cut grass mulch should be removed from the slope benches All normal maintenance activities including grass mowing shall be recorded on the Maintenance Record Form attached to this Plan

Animal borrows or other cover soil damage shall be repaired to the conditions of the surrounding areas Normal maintenance repairs are limited to the repair of the soil or channel surfaces to a depth of one foot from the constructed grade and these repairs can be made without specific written approval of the EPA No repairs shall be made to the geotextile fabric drainage sand geomembrane or underlying materials without specific written approval of the EPA

Significant accumulations of silt or debris that collects in the drainage systems must be removed All of the drainage channels are designed with freeboard above the flow depth of the 100-year frequency storm In the slope benches on the landfill cover the maximum allowable sediment depth is 6 inches above the surface of the rip-rap stone The allowable sediment depth in pipes and the flat bottom channels is 2 inches Any debris that restricts drainage flow shall be removed from drainage channels and structures The stone rip-rap linings of the drainage channels is provided to stabilize the surface from erosion when vegetation is not present Over time the rip-rap channels will accumulate soil material and may support the growth of grass and this is acceptable In fact the grass vegetation should provide some stormwater quality benefit

If normal maintenance requires the removal of sediment or debris from drainage channels or structures the work shall be performed with typical equipment used for the purpose taking care not to damage the surface of the cover system or any other site features and structures as part of the work In general the smallest equipment that will perform a specific task should be used to minimize potential damage to the facility If there is any possibility that damage was done to underlying cover materials or systems it shall be reported and investigated accordingly All normal maintenance activities shall be recorded on the Maintenance Record Form attached to this Plan

Inspections of the site shall be conducted by a qualified Professional Engineer within 30 days before the date of each Progress Report With one exception the inspections shall include all of the items identified in this Plan for regular monitoring The exception is that settlement monitoring will only be conducted annually for the November Progress Report Inspections shall include observations of the entire landfill cover system and the surrounding areas Each inspection shall be documented on the Inspection Record Form attached to this Plan Evaluations and assessments of the observed conditions shall be included in a letter report An outline of the report format is attached to this Plan

A copy of the record drawings and project specifications for the cover system construction shall be maintained by the City of Saco at the Public Works Department These documents shall be referenced whenever maintenance or inspections are performed A reduced copy of the record drawing As-Built

9606401 3 OV2699

Site Plan (attached as a Figure) shall be included with each inspection report in order to show the location of any identified problems or maintenance issues

4 OPERATIONAL SAFETY PLAN

All inspections and maintenance work at this site shall be performed in conformance with the Woodard amp Curran Health and Safety Plan (HASP) or another HASP that is at least as stringent as this one Requirements of the Occupational Safety and Health Act (OSHA) 29 CFR provide the basic safety requirements that shall be followed for all activities on the site

Although the possibility of exposure to hazardous chemicals is not anticipated all individuals at the site should be aware that the cover system is acting as a barrier to potentially hazardous materials buried m the landfill Any actions that could uncover these materials should be avoided If a condition is observed that indicate that potentially hazardous materials may be entering the environment the observation should be reported to the Maine DEP and the EPA

The more likely dangers at the site are accidents related to normal maintenance and inspection activities To prevent workplace accidents safety should be emphasized and practiced during all site activities The key to safety is good common sense Some guidelines for safety practices are the following

STOP AND THINK DOUBLE CHECK AVOID EXTREMES (such as overwork fatigue anger tension and haste)

Maintenance and inspection activities present many opportunities for physical injury to occur This site contains steep slopes and rip-rap drainage structures which could make otherwise normal activities more unpredictable and dangerous The use of equipment at this site should be done with particular care due to the special site conditions Wearing the proper protective clothing and sturdy boots and using common sense can prevent many injuries from occurring Appropriate gloves should be worn when handling materials or working on equipment It is noted that the landfill surface particularly the rip-rap stone channels may harbor bee or wasp nests Persons with an allergy to bee stings should take appropriate precautions

5 EVALUATION OF VEGETATIVE GROWTH EROSION AND OTHER SITE CONDITIONS

The condition of the vegetative growth and signs of erosion shall be evaluated after each inspection It is important for the grass to be kept mowed so that no woody plants become established The grass should be healthy and uniform The inspections should thorough observations of any unusual conditions such as areas where water does not drain wet or soft spots any bulges or depressions in the cover system and any signs of bulk soil movement or significant cracks Similar conditions should be identified in the stormwater management basin and in the areas surrounding the landfill cover system The inspections should also look for signs of improper uses of the site such as off-road vehicle use or other damage

9606401 4 032699

Wherever an area of poor grass growth is at least 100 square feet (10 by 10 or equivalent) the potential causes for this condition should be assessed If it is not due primarily to seasonal weather conditions (ie no ram) then further investigations should be performed to determine if fertilizer or other soil conditioners are necessary The investigations shall be designed to determine if the soil and nutrient conditions meet the requirements of the project specifications If discrete areas of the grass become stressed causes for this problem should be assessed and the problem corrected In general poor grass growth should be corrected by amending the soil as necessary and applying grass seed fertilizer and mulch as specified m the project specifications Section 02485 - Topsoil Seed and Mulch

Any areas of erosion shall be identified by the inspections and shown on the inspection Site Plan Normal maintenance shall be performed and documented in a Maintenance Record Form Any repair work shall be performed according to the requirements in the project specifications A recurring or major problem with erosion shall be addressed as described in the following section of this Plan

6 ASSESSMENT OF EROSION CONTROLS AND STORMWATER MANAGEMENT BASIN

The condition and performance of erosion control systems and the stormwater management basin shall be assessed after each inspection Even if all systems are operating properly normal maintenance will be required as noted in Section 3 of this Plan That section also identifies the depth of sediment that is allowable in the various drainage channels and the procedures for cleaning However if there is evidence of poor performance or damage to systems it is necessary to review the adequacy of the erosion control features Poor performance could include the recurrence of sedimentation m specific places or recurring damage to systems that require repairs In such cases an assessment of the problem shall be performed and a solution identified and implemented

The stormwater management basin is intended to control the rate of runoff from the site by limiting the flow from the basin to a pre-development rate of flow that is much less than the instantaneous runoff rate from the landfill cover area It is anticipated that the lower elevations of the basin along the berm on the east side will have a ground surface condition that is usually wet allowing wetland vegetation to become established This is normal operation and is acceptable The basin should be inspected for any obvious structural or erosion damage and the outlet structure should be inspected for proper operation If damage or clogging is identified the improper conditions shall be corrected in accordance with the record drawings and the project specifications including Section 02715 - Site Piping If sediments reach a depth of 6 inches they shall be removed during dry conditions The removal of sediments shall be performed with tracked equipment that limits the compaction of the soils and quality assurance shall be provided by observation and inspection of the repair activity All maintenance and repair activity shall be recorded on the Maintenance Record Form attached to this Plan

It is noted that groundwater from the closed landfill on the north side of Sandy Brook is proposed to be treated and pumped into Culvert 3 and will then enter the northern end of the stormwater management basin This flow will be a relatively small quantity compared to storm flow quantities so most of this water will enter the wet pool in the stormwater basin and infiltrate into the groundwater

9606401 5 012699

7 POTENTIAL PROBLEMS AND CONTINGENCY PLAN

A number of the potential problems that could occur to the landfill cover system at the site have been identified along with the appropriate contingency response Some items are considered normal maintenance activities as noted previously while some are major repairs that must be performed by a specialty contractor after approval by the EPA Work that can be performed without the specific approval of the EPA includes any maintenance and repair to the cover and slope benches to a depth of one foot below the constructed surface grade or any repairs beyond the limits of the cover system In any case all repairs shall be performed in accordance with the record drawings and project specifications including the quality controlquality assurance procedures These potential problems and responses are summarized in the table on the next page

While unlikely a more severe problem could occur A severe problem could result from an earthquake a failure of the constructed cover system due to other causes or a release of contaminants into the environment In such a case the inspector should immediately notify the EPA and the DEP and engage a qualified Professional Engineer in order to develop a more detailed and appropriate response

Potential Problem Contingency Response 1 Erosion of surface soil Identify the cause of the erosion if possible and

eliminaterepair it Place new soil in any gullies spread topsoil seed and heavy mulch

2 Sedimentation in drainage channels or pipes Identify the sourcecause of the sedimentation if possible and correct it Remove the sediment to maintain full capacity of the structures

3 Erosion in drainage channels or damage to Identify the cause of the problem if possible and pipes eliminaterepair it Place new rip-rap (and repair

gabions) in any eroded channels install topsoil seed and heavy mulch as necessary Damaged pipes shall be repaired to their original condition

4 Damaged gas vent riser pipe Repair damaged pipe as appropriate Holes smaller than 1-inch diameter can be patched any larger holes or a broken pipe must be cut and fusion-welded by a qualified contractor

5 Differential settlement of cover system Some differential settlement is expected but if drainage is impaired andor water is ponding on the cover surface (or in drainage channels) proper drainage must be restored The initial response shall be to fill depressions with soil or repair drainage channels to drain The cause of the drainage problem shall be assessed in the following Progress Report If repairs to the underlying membrane system are recommended they shall be approved by the EPA before proceeding

96064 01 032699

Potential Problem Contingency Response 6 Soil movement that exposes geomembrane Any significant soil movement or other cause that

(Or other obvious damage to the exposes the geomembrane shall be investigated geomembrane) and assessed in the following Progress Report An

initial response shall be as appropriate to control further damage to the cover system If repairs to the underlying geomembrane system are necessary they shall be approved by the EPA before proceeding

8 EVALUATION OF STABILITY

The stability of the site shall be qualitatively assessed after each inspection Indications of unstable soil and cover system conditions could include longitudinal cracks or depressions in the soil surface or evidence of slumping or impaired drainage at the lower areas of slopes or in drainage channels If either of these conditions are identified additional investigations should be performed to determine if site or slope stability may be impaired At a minimum the identified area of surface depression should be surveyed at the time that settlement monitoring is performed Surveys should then be performed annually to monitor for changes over time The procedures listed in Section 12 of this Plan should be followed for further analysis

The gabion wall at the entrance to Culvert 1 on the eastern side of the landfill should be monitored for tilt as an indication of slope stability The specific location for measuring the tilt is described on the Inspection Record Form attached to this Plan Any changes in tilt of the wall should be identified in the Progress Reports and the implications on stability shall be qualitatively assessed

9 ASSESSMENT OF PASSIVE GAS VENTING SYSTEM

The condition and performance of the passive gas venting system shall be qualitatively assessed after each inspection The condition of the gas vents will be determined by visual observation of the gas vent risers and the adjacent cover surface conditions The vents should be protruding from the cover system with the outlet at least 7 feet above the cover surface (Some leaning of the HDPE pipes is expected) The screens should be in place on the ends of the pipes Where the pipe boots are visible there should be no signs of damage The surrounding soil should be firmly supporting the riser pipe with no voids or spaces that could indicate movement of the riser or adjacent soil If any improper conditions are observed additional investigations should be performed to determine if there is damage to the vent structure that requires repairs

Signs of poor performance would include a clogged gas vent screen or an indication that gas is releasing through or beyond the cover system This condition is usually indicated by stress in the vegetation that can not otherwise be explained If this is the case additional investigations should be performed to determine if gas is not being properly vented and if further repairs or improvements are required

96064 01 0326 99

As an indication of gas vent physical conditions over time the tilt or lean of each gas vent riser should be measured annually during the inspection prior to the NovemberDecember Progress Report As part of the inspection report the data shall be compared to the baseline data from previous inspections A variation of about 2 inches in the angle measurement is expected to occur from variations m temperature and measurement accuracy If any of the gas vents exhibit an unusual change in the tilt angle (more than 3 inches from the previous condition) they should be investigated in more detail during the following inspections

10 EVALUATION OF SANDY BROOK SEDIMENT REMOVAL AREA

The Sandy Brook Sediment Removal Area is located to the north of monitoring well MW-95-4 and is noted as Seep Area on the record drawing Site Plan It is an area that had previously been a depression in the ground next to Sandy Brook The area contained contaminated sediments that have been removed and the area has been filled with soil

The conditions at the Sandy Brook Sediment Removal Area shall be evaluated after each inspection The inspection shall look for evidence of discoloration (ie iron staining) erosion from surface drainage or from high levels of flow in the Brook that could result in a sediment discharge to the Brook Any identified problems shall be repaired to prevent potential impacts to the Brook Repairs shall consist of filling and erosion control construction in accordance with the project specifications

11 IMPACT ON WETLANDS

The impact on the surrounding wetlands shall be evaluated in accordance with the wetlands restoration monitoring plan that has not been developed at the time this PRSC Plan was prepared It is anticipated that the wetlands inspections will be conducted at the same time as the normal site inspections but this will need to be refined and clarified in the wetlands monitoring plan The correction of any identified impact needs to be evaluated and approved by the EPA before any action is implemented

12 SETTLEMENT MONITORING

Settlement of the cover system is expected to occur over time as the waste material continues to decompose This anticipated settlement results in a relatively uniform subsidence of the ground surface is not expected to damage the cover system It is differential settlement that is undesirable because it could damage the cover system and this differential settlement will be identified by problems with surface drainage or by general observations of surface conditions However overall settlement of the landfill will be monitored in order to document the rate and magnitude of settlement The monitoring will occur m the fall of each year and will be reported in the NovemberDecember Progress Report

Settlement monitoring will be conducted by measuring the elevations of monitoring points established on each of four gas vents numbers 7 8 9 and 10 These are the vents located along the highest profile of the landfill and will therefore measure the areas where the greatest settlement is expected The gas vents

9606401 8 OV26 99

only penetrate into the waste about 5 feet so they accurately reflect the elevation and settlement of the landfill surface

If the landfill inspections identify an area with a depression on the surface of the cover system where water does not drain properly or if an area larger than 400 square feet (20 feet by 20 feet or equivalent) has settled by more than 1 foot from the adjacent proper elevations the area needs to be documented and monitored At a minimum the location and elevations of the surface depression should be surveyed at the time that settlement monitoring is performed Surveys should then be performed annually to monitor for changes over time If an area is repaired by filling a depression and it does not continue to settle for the next two years of surveys the annual surveying can be discontinued If a depression is filled and continues to settle after two years the area shall be evaluated to determine if the mobilized tensile stress in the geomembrane exceeds allowable values If it does a geomembrane investigation plan shall be recommended in the monitoring report and the plan shall be approved by the EPA before it is performed

9606401 9 032699

Outline of Sample Progress Report Post-Removal Site Control Plan Saco Municipal Landfill Closure

Saco Maine

1 Summary of PRSC activities that have occurred since last report

2 Summary and evaluation of cover system inspection results bull Identify critical issues or problems bull Characterize performance of vegetative growth and erosion controls Determine if poor

growth or erosion is occurring in particular locations bull Characterize the performance of slope benches and rip-rap downdrains bull Assess the significance of any identified drainage problems soft or wet areas or other

cover system damage bull Assess the performance of the gas venting system bull Characterize the performance of the perimeter drainage zone and outlet pipes

3 Summary and evaluation of conditions outside the limits of the cover system bull Identify critical issues or problems including any indications of leachate seeps bull Characterize the performance of the gabion structure at inlet to Culvert 1 bull Characterize performance of perimeter drainage channels and erosion controls bull Determine if poor growth or erosion is occurring in particular locations bull Assess the condition of the culverts manholes and the rip-rap oulet plunge pools bull Assess the condition and performance of the stormwater detention basin

4 Assess the site and slope stability based on qualitative data

5 Evaluate the conditions at the Sandy Brook Sediment Removal Area Identify problems that should be repaired in order to prevent a sediment discharge to Sandy Brook

6 Identify and evaluate any potential impacts on the surrounding wetlands in accordance with the wetlands monitoring plan once it is developed

7 Summary of the results of settlement monitoring over the post closure period

8 Summarize results of Significant Weather event reports

9 Recommend actions and maintenance activities to occur before the next inspection

Appendices Maintenance Reports Inspection Reports Significant Weather Event Reports

FIGURES

95093 14 DRAF F 012699

MONITORING FORMS

9509314 DRAFT 032filtraquo

Table of Contents

1 Introduction amp General Information bull 1

2 Record Keeping and Reporting 1

3 Normal Operations and Maintenance 2

4 Operational Safety Plan 4

5 Evaluation of Vegetative Growth Erosion and Other Site Conditions 4

6 Assessment of Erosion Controls and Stormwater Management Basin 5

7 Potential Problems and Contingency Plan 6

8 Evaluation of Stability 7

9 Assessment of Passive Gas Venting System 7

10 Evaluation of Sandy Brook Sediment Removal Area 8

11 Impact on Wetlands 8

12 Settlement Monitoring 8

Outline of Sample Progress Report

Figures

1 Area Site Plan (reduced Record Drawing sheet 2 of 11)

2 As-Built Grading Plan (reduced Record Drawing sheet 5A of 11)

Forms

Maintenance Record Form Significant Weather Event Form Inspection Record Form

9606401 - i - March 26 1999

1 INTRODUCTION amp GENERAL INFORMATION

This Post Removal Site Control (PRSC) Plan has been prepared in accordance with the Administrative Order of Consent (Order) (US Environmental Protection Agency [USEPA] Comprehensive Environmental Response Compensation and Liability Act [CERCLA] Docket No I-CERCLA-95-1069) and Appendix B (Non-Time Critical Removal Statement of Work) to the Order for the Saco Municipal Landfill (SML) Superfund site This document is one of six deliverable documents that are required under Article V of Appendix B This PRSC Plan applies primarily to the multi-layer cap that is constructed on Landfill Areas 3 and 4 and the specific incidental features identified in this Plan The PRSC activities shall be conducted for 30 years after the completion of the NTCRA unless otherwise approved by the EPA The overall site features (prior to project construction) are shown on the Area Site Plan from the Project Record Drawings a copy of which is attached to this PRSC Plan

The purpose of the PRSC Plan is to define those operation and maintenance activities that will be performed to maintain the landfill cap and associated drainage systems The objective of the landfill cap and drainage systems is to prevent infiltration of water into the waste within the landfill and control the drainage of water on and away from the cap in a manner that does not cause erosion of the cover or drainage systems or allow sediment to flow into Sandy Brook By performing the maintenance and monitoring activities in a timely manner as outlined in this Plan the potential for major repairs and longshyterm costs will be reduced

The cover system cap on Landfill Areas 3 and 4 covers an area of approximately 13 acres The cover system was designed to meet the performance requirements of the Resource Conservation and Recovery Act (RCRA) Subtitle C regulations and existing requirements of the Maine DEP and US EPA The cover system consists (from the bottom) of a base soil layer 9 inches of gas collection sand 24 inches of low-permeability soil (clay) a synthetic LLDPE 60 mil textured geomembrane 12 inches of drainage sand a geotextile fabric 12 to 18 inches of select borrow soil and 6 inches of topsoil with an erosion control blanket to control erosion before the vegetative grass cover becomes established The cover system also includes 20 passive gas vents surface water diversion benches perimeter ditches culverts and a stormwater management basin

The project was constructed as documented in the Final Completion of Removal Action Report which includes the record drawings the project specifications and the Construction Quality Assurance Plan These documents should be consulted for detailed information about the constructed systems Any work performed on the landfill site as described in this plan shall be performed under the direction of a City representative who is thoroughly familiar with this PRSC Plan the Completion of Removal Action Report and the Long-Term Monitoring Plan An archive copy of these three documents shall be maintained by the City of Saco and a working copy of the documents should be possessed by the City representative(s) who are responsible for the site operation and maintenance

2 RECORD KEEPING AND REPORTING

The PRSC activities shall be initiated upon completion of construction of the NTCRA Progress reports shall be submitted to the EPA and the Maine DEP throughout the period of the PRSC as described in this Plan and shall address each of the items that are identified in this Plan They will identify all of the

9606401 1 032699

PRSC activities that were performed since the previous PRSC Progress Report and those activities that will be performed in the time period until the next PRSC Progress Report The reports shall also include a summary of the results of any PRSC tests or evaluations completed since the last report and they shall identify any corrective measures that have been or need to be completed

Progress Reports shall be submitted three times per year for the first two years following approval of the PRSC Plan by EPA in June September and December for inspections conducted the previous month Inspections will be performed by a qualified Professional Engineer using the attached Inspection Record Form to ensure that all inspection items are addressed For the next eight years the PRSC Progress Reports shall be submitted in June and November of each year Thereafter Progress Reports shall be submitted annually in November

The site shall also be inspected after each significant weather event during the first two years of the post-removal monitoring program or for six months after a major re-vegetation activity (exceeding an area of 10000 square feet) A significant weather event is defined as 1-inch or more of rainfall in a 24 hour period The inspection may be performed by a qualified representative of the City of Saco and shall be documented on the Significant Weather Event form attached to this Plan If erosion is observed or if sediment containing run-off is entering Sandy Brook the US EPA and Maine DEP shall be notified immediately

Contact names addresses and phone numbers for reporting and emergency notification are as follows

Mr Edward Hathaway Mr Wilkes Harper USEPA Region 1 Maine Department of Environmental Protection 1 Congress Street Bureau of Remediation Suite 1100 (Mail code HBT) State House Station 17 Boston MA 02203-2211 Augusta ME 04333-0017 Phone 617-918-1372 Phoneshy 207-287-2651 Fax 617-918-1291 Fax 207-287-7826 Emergency ONLY (for uncontrolled releases spills Emergency Response ONLY (for uncontrolled or fires) 1-800-424-8802 releases spills or fires)- 1-800-482-0777

3 NORMAL OPERATIONS AND MAINTENANCE

Normal operations and maintenance for this site will consist primarily of landscaping care and site inspections The purpose of the maintenance program is to identify and correct any damage that may occur to the engineered systems at the site either by natural causes or by vandalism that could interfere with the proper functioning of these systems If damage is identified the cause of the damage shall be investigated and corrective maintenance or repairs shall be implemented

It is important to maintain and inspect the site so as to prevent more serious problems The grass must be mowed annually in order to prevent the growth of woody vegetation which could damage the cover system Erosion of soils could result in clogged drainage systems or exposure of the underlying geotextile or the geomembrane layers It is important that all drainage systems are operating properly in

9606401 2 OV2699

order to prevent saturation of soils Saturated soils are the most likely cause of slope failure resulting in expensive repairs and possible environmental damage

The normal landscaping care will include grass mowing drainage system cleaning and related maintenance Typical maintenance could include the repair of eroded soil or damaged drainage systems This work shall be the responsibility of the City of Saco In order to reduce potential impact to nesting birds the grass should be mowed only after July 15 each year The cut grass may either be left m place as mulch or removed Any thick deposits of cut grass mulch should be removed from the slope benches All normal maintenance activities including grass mowing shall be recorded on the Maintenance Record Form attached to this Plan

Animal borrows or other cover soil damage shall be repaired to the conditions of the surrounding areas Normal maintenance repairs are limited to the repair of the soil or channel surfaces to a depth of one foot from the constructed grade and these repairs can be made without specific written approval of the EPA No repairs shall be made to the geotextile fabric drainage sand geomembrane or underlying materials without specific written approval of the EPA

Significant accumulations of silt or debris that collects in the drainage systems must be removed All of the drainage channels are designed with freeboard above the flow depth of the 100-year frequency storm In the slope benches on the landfill cover the maximum allowable sediment depth is 6 inches above the surface of the rip-rap stone The allowable sediment depth in pipes and the flat bottom channels is 2 inches Any debris that restricts drainage flow shall be removed from drainage channels and structures The stone rip-rap linings of the drainage channels is provided to stabilize the surface from erosion when vegetation is not present Over time the rip-rap channels will accumulate soil material and may support the growth of grass and this is acceptable In fact the grass vegetation should provide some stormwater quality benefit

If normal maintenance requires the removal of sediment or debris from drainage channels or structures the work shall be performed with typical equipment used for the purpose taking care not to damage the surface of the cover system or any other site features and structures as part of the work In general the smallest equipment that will perform a specific task should be used to minimize potential damage to the facility If there is any possibility that damage was done to underlying cover materials or systems it shall be reported and investigated accordingly All normal maintenance activities shall be recorded on the Maintenance Record Form attached to this Plan

Inspections of the site shall be conducted by a qualified Professional Engineer within 30 days before the date of each Progress Report With one exception the inspections shall include all of the items identified in this Plan for regular monitoring The exception is that settlement monitoring will only be conducted annually for the November Progress Report Inspections shall include observations of the entire landfill cover system and the surrounding areas Each inspection shall be documented on the Inspection Record Form attached to this Plan Evaluations and assessments of the observed conditions shall be included in a letter report An outline of the report format is attached to this Plan

A copy of the record drawings and project specifications for the cover system construction shall be maintained by the City of Saco at the Public Works Department These documents shall be referenced whenever maintenance or inspections are performed A reduced copy of the record drawing As-Built

9606401 3 OV2699

Site Plan (attached as a Figure) shall be included with each inspection report in order to show the location of any identified problems or maintenance issues

4 OPERATIONAL SAFETY PLAN

All inspections and maintenance work at this site shall be performed in conformance with the Woodard amp Curran Health and Safety Plan (HASP) or another HASP that is at least as stringent as this one Requirements of the Occupational Safety and Health Act (OSHA) 29 CFR provide the basic safety requirements that shall be followed for all activities on the site

Although the possibility of exposure to hazardous chemicals is not anticipated all individuals at the site should be aware that the cover system is acting as a barrier to potentially hazardous materials buried m the landfill Any actions that could uncover these materials should be avoided If a condition is observed that indicate that potentially hazardous materials may be entering the environment the observation should be reported to the Maine DEP and the EPA

The more likely dangers at the site are accidents related to normal maintenance and inspection activities To prevent workplace accidents safety should be emphasized and practiced during all site activities The key to safety is good common sense Some guidelines for safety practices are the following

STOP AND THINK DOUBLE CHECK AVOID EXTREMES (such as overwork fatigue anger tension and haste)

Maintenance and inspection activities present many opportunities for physical injury to occur This site contains steep slopes and rip-rap drainage structures which could make otherwise normal activities more unpredictable and dangerous The use of equipment at this site should be done with particular care due to the special site conditions Wearing the proper protective clothing and sturdy boots and using common sense can prevent many injuries from occurring Appropriate gloves should be worn when handling materials or working on equipment It is noted that the landfill surface particularly the rip-rap stone channels may harbor bee or wasp nests Persons with an allergy to bee stings should take appropriate precautions

5 EVALUATION OF VEGETATIVE GROWTH EROSION AND OTHER SITE CONDITIONS

The condition of the vegetative growth and signs of erosion shall be evaluated after each inspection It is important for the grass to be kept mowed so that no woody plants become established The grass should be healthy and uniform The inspections should thorough observations of any unusual conditions such as areas where water does not drain wet or soft spots any bulges or depressions in the cover system and any signs of bulk soil movement or significant cracks Similar conditions should be identified in the stormwater management basin and in the areas surrounding the landfill cover system The inspections should also look for signs of improper uses of the site such as off-road vehicle use or other damage

9606401 4 032699

Wherever an area of poor grass growth is at least 100 square feet (10 by 10 or equivalent) the potential causes for this condition should be assessed If it is not due primarily to seasonal weather conditions (ie no ram) then further investigations should be performed to determine if fertilizer or other soil conditioners are necessary The investigations shall be designed to determine if the soil and nutrient conditions meet the requirements of the project specifications If discrete areas of the grass become stressed causes for this problem should be assessed and the problem corrected In general poor grass growth should be corrected by amending the soil as necessary and applying grass seed fertilizer and mulch as specified m the project specifications Section 02485 - Topsoil Seed and Mulch

Any areas of erosion shall be identified by the inspections and shown on the inspection Site Plan Normal maintenance shall be performed and documented in a Maintenance Record Form Any repair work shall be performed according to the requirements in the project specifications A recurring or major problem with erosion shall be addressed as described in the following section of this Plan

6 ASSESSMENT OF EROSION CONTROLS AND STORMWATER MANAGEMENT BASIN

The condition and performance of erosion control systems and the stormwater management basin shall be assessed after each inspection Even if all systems are operating properly normal maintenance will be required as noted in Section 3 of this Plan That section also identifies the depth of sediment that is allowable in the various drainage channels and the procedures for cleaning However if there is evidence of poor performance or damage to systems it is necessary to review the adequacy of the erosion control features Poor performance could include the recurrence of sedimentation m specific places or recurring damage to systems that require repairs In such cases an assessment of the problem shall be performed and a solution identified and implemented

The stormwater management basin is intended to control the rate of runoff from the site by limiting the flow from the basin to a pre-development rate of flow that is much less than the instantaneous runoff rate from the landfill cover area It is anticipated that the lower elevations of the basin along the berm on the east side will have a ground surface condition that is usually wet allowing wetland vegetation to become established This is normal operation and is acceptable The basin should be inspected for any obvious structural or erosion damage and the outlet structure should be inspected for proper operation If damage or clogging is identified the improper conditions shall be corrected in accordance with the record drawings and the project specifications including Section 02715 - Site Piping If sediments reach a depth of 6 inches they shall be removed during dry conditions The removal of sediments shall be performed with tracked equipment that limits the compaction of the soils and quality assurance shall be provided by observation and inspection of the repair activity All maintenance and repair activity shall be recorded on the Maintenance Record Form attached to this Plan

It is noted that groundwater from the closed landfill on the north side of Sandy Brook is proposed to be treated and pumped into Culvert 3 and will then enter the northern end of the stormwater management basin This flow will be a relatively small quantity compared to storm flow quantities so most of this water will enter the wet pool in the stormwater basin and infiltrate into the groundwater

9606401 5 012699

7 POTENTIAL PROBLEMS AND CONTINGENCY PLAN

A number of the potential problems that could occur to the landfill cover system at the site have been identified along with the appropriate contingency response Some items are considered normal maintenance activities as noted previously while some are major repairs that must be performed by a specialty contractor after approval by the EPA Work that can be performed without the specific approval of the EPA includes any maintenance and repair to the cover and slope benches to a depth of one foot below the constructed surface grade or any repairs beyond the limits of the cover system In any case all repairs shall be performed in accordance with the record drawings and project specifications including the quality controlquality assurance procedures These potential problems and responses are summarized in the table on the next page

While unlikely a more severe problem could occur A severe problem could result from an earthquake a failure of the constructed cover system due to other causes or a release of contaminants into the environment In such a case the inspector should immediately notify the EPA and the DEP and engage a qualified Professional Engineer in order to develop a more detailed and appropriate response

Potential Problem Contingency Response 1 Erosion of surface soil Identify the cause of the erosion if possible and

eliminaterepair it Place new soil in any gullies spread topsoil seed and heavy mulch

2 Sedimentation in drainage channels or pipes Identify the sourcecause of the sedimentation if possible and correct it Remove the sediment to maintain full capacity of the structures

3 Erosion in drainage channels or damage to Identify the cause of the problem if possible and pipes eliminaterepair it Place new rip-rap (and repair

gabions) in any eroded channels install topsoil seed and heavy mulch as necessary Damaged pipes shall be repaired to their original condition

4 Damaged gas vent riser pipe Repair damaged pipe as appropriate Holes smaller than 1-inch diameter can be patched any larger holes or a broken pipe must be cut and fusion-welded by a qualified contractor

5 Differential settlement of cover system Some differential settlement is expected but if drainage is impaired andor water is ponding on the cover surface (or in drainage channels) proper drainage must be restored The initial response shall be to fill depressions with soil or repair drainage channels to drain The cause of the drainage problem shall be assessed in the following Progress Report If repairs to the underlying membrane system are recommended they shall be approved by the EPA before proceeding

96064 01 032699

Potential Problem Contingency Response 6 Soil movement that exposes geomembrane Any significant soil movement or other cause that

(Or other obvious damage to the exposes the geomembrane shall be investigated geomembrane) and assessed in the following Progress Report An

initial response shall be as appropriate to control further damage to the cover system If repairs to the underlying geomembrane system are necessary they shall be approved by the EPA before proceeding

8 EVALUATION OF STABILITY

The stability of the site shall be qualitatively assessed after each inspection Indications of unstable soil and cover system conditions could include longitudinal cracks or depressions in the soil surface or evidence of slumping or impaired drainage at the lower areas of slopes or in drainage channels If either of these conditions are identified additional investigations should be performed to determine if site or slope stability may be impaired At a minimum the identified area of surface depression should be surveyed at the time that settlement monitoring is performed Surveys should then be performed annually to monitor for changes over time The procedures listed in Section 12 of this Plan should be followed for further analysis

The gabion wall at the entrance to Culvert 1 on the eastern side of the landfill should be monitored for tilt as an indication of slope stability The specific location for measuring the tilt is described on the Inspection Record Form attached to this Plan Any changes in tilt of the wall should be identified in the Progress Reports and the implications on stability shall be qualitatively assessed

9 ASSESSMENT OF PASSIVE GAS VENTING SYSTEM

The condition and performance of the passive gas venting system shall be qualitatively assessed after each inspection The condition of the gas vents will be determined by visual observation of the gas vent risers and the adjacent cover surface conditions The vents should be protruding from the cover system with the outlet at least 7 feet above the cover surface (Some leaning of the HDPE pipes is expected) The screens should be in place on the ends of the pipes Where the pipe boots are visible there should be no signs of damage The surrounding soil should be firmly supporting the riser pipe with no voids or spaces that could indicate movement of the riser or adjacent soil If any improper conditions are observed additional investigations should be performed to determine if there is damage to the vent structure that requires repairs

Signs of poor performance would include a clogged gas vent screen or an indication that gas is releasing through or beyond the cover system This condition is usually indicated by stress in the vegetation that can not otherwise be explained If this is the case additional investigations should be performed to determine if gas is not being properly vented and if further repairs or improvements are required

96064 01 0326 99

As an indication of gas vent physical conditions over time the tilt or lean of each gas vent riser should be measured annually during the inspection prior to the NovemberDecember Progress Report As part of the inspection report the data shall be compared to the baseline data from previous inspections A variation of about 2 inches in the angle measurement is expected to occur from variations m temperature and measurement accuracy If any of the gas vents exhibit an unusual change in the tilt angle (more than 3 inches from the previous condition) they should be investigated in more detail during the following inspections

10 EVALUATION OF SANDY BROOK SEDIMENT REMOVAL AREA

The Sandy Brook Sediment Removal Area is located to the north of monitoring well MW-95-4 and is noted as Seep Area on the record drawing Site Plan It is an area that had previously been a depression in the ground next to Sandy Brook The area contained contaminated sediments that have been removed and the area has been filled with soil

The conditions at the Sandy Brook Sediment Removal Area shall be evaluated after each inspection The inspection shall look for evidence of discoloration (ie iron staining) erosion from surface drainage or from high levels of flow in the Brook that could result in a sediment discharge to the Brook Any identified problems shall be repaired to prevent potential impacts to the Brook Repairs shall consist of filling and erosion control construction in accordance with the project specifications

11 IMPACT ON WETLANDS

The impact on the surrounding wetlands shall be evaluated in accordance with the wetlands restoration monitoring plan that has not been developed at the time this PRSC Plan was prepared It is anticipated that the wetlands inspections will be conducted at the same time as the normal site inspections but this will need to be refined and clarified in the wetlands monitoring plan The correction of any identified impact needs to be evaluated and approved by the EPA before any action is implemented

12 SETTLEMENT MONITORING

Settlement of the cover system is expected to occur over time as the waste material continues to decompose This anticipated settlement results in a relatively uniform subsidence of the ground surface is not expected to damage the cover system It is differential settlement that is undesirable because it could damage the cover system and this differential settlement will be identified by problems with surface drainage or by general observations of surface conditions However overall settlement of the landfill will be monitored in order to document the rate and magnitude of settlement The monitoring will occur m the fall of each year and will be reported in the NovemberDecember Progress Report

Settlement monitoring will be conducted by measuring the elevations of monitoring points established on each of four gas vents numbers 7 8 9 and 10 These are the vents located along the highest profile of the landfill and will therefore measure the areas where the greatest settlement is expected The gas vents

9606401 8 OV26 99

only penetrate into the waste about 5 feet so they accurately reflect the elevation and settlement of the landfill surface

If the landfill inspections identify an area with a depression on the surface of the cover system where water does not drain properly or if an area larger than 400 square feet (20 feet by 20 feet or equivalent) has settled by more than 1 foot from the adjacent proper elevations the area needs to be documented and monitored At a minimum the location and elevations of the surface depression should be surveyed at the time that settlement monitoring is performed Surveys should then be performed annually to monitor for changes over time If an area is repaired by filling a depression and it does not continue to settle for the next two years of surveys the annual surveying can be discontinued If a depression is filled and continues to settle after two years the area shall be evaluated to determine if the mobilized tensile stress in the geomembrane exceeds allowable values If it does a geomembrane investigation plan shall be recommended in the monitoring report and the plan shall be approved by the EPA before it is performed

9606401 9 032699

Outline of Sample Progress Report Post-Removal Site Control Plan Saco Municipal Landfill Closure

Saco Maine

1 Summary of PRSC activities that have occurred since last report

2 Summary and evaluation of cover system inspection results bull Identify critical issues or problems bull Characterize performance of vegetative growth and erosion controls Determine if poor

growth or erosion is occurring in particular locations bull Characterize the performance of slope benches and rip-rap downdrains bull Assess the significance of any identified drainage problems soft or wet areas or other

cover system damage bull Assess the performance of the gas venting system bull Characterize the performance of the perimeter drainage zone and outlet pipes

3 Summary and evaluation of conditions outside the limits of the cover system bull Identify critical issues or problems including any indications of leachate seeps bull Characterize the performance of the gabion structure at inlet to Culvert 1 bull Characterize performance of perimeter drainage channels and erosion controls bull Determine if poor growth or erosion is occurring in particular locations bull Assess the condition of the culverts manholes and the rip-rap oulet plunge pools bull Assess the condition and performance of the stormwater detention basin

4 Assess the site and slope stability based on qualitative data

5 Evaluate the conditions at the Sandy Brook Sediment Removal Area Identify problems that should be repaired in order to prevent a sediment discharge to Sandy Brook

6 Identify and evaluate any potential impacts on the surrounding wetlands in accordance with the wetlands monitoring plan once it is developed

7 Summary of the results of settlement monitoring over the post closure period

8 Summarize results of Significant Weather event reports

9 Recommend actions and maintenance activities to occur before the next inspection

Appendices Maintenance Reports Inspection Reports Significant Weather Event Reports

FIGURES

95093 14 DRAF F 012699

MONITORING FORMS

9509314 DRAFT 032filtraquo

1 INTRODUCTION amp GENERAL INFORMATION

This Post Removal Site Control (PRSC) Plan has been prepared in accordance with the Administrative Order of Consent (Order) (US Environmental Protection Agency [USEPA] Comprehensive Environmental Response Compensation and Liability Act [CERCLA] Docket No I-CERCLA-95-1069) and Appendix B (Non-Time Critical Removal Statement of Work) to the Order for the Saco Municipal Landfill (SML) Superfund site This document is one of six deliverable documents that are required under Article V of Appendix B This PRSC Plan applies primarily to the multi-layer cap that is constructed on Landfill Areas 3 and 4 and the specific incidental features identified in this Plan The PRSC activities shall be conducted for 30 years after the completion of the NTCRA unless otherwise approved by the EPA The overall site features (prior to project construction) are shown on the Area Site Plan from the Project Record Drawings a copy of which is attached to this PRSC Plan

The purpose of the PRSC Plan is to define those operation and maintenance activities that will be performed to maintain the landfill cap and associated drainage systems The objective of the landfill cap and drainage systems is to prevent infiltration of water into the waste within the landfill and control the drainage of water on and away from the cap in a manner that does not cause erosion of the cover or drainage systems or allow sediment to flow into Sandy Brook By performing the maintenance and monitoring activities in a timely manner as outlined in this Plan the potential for major repairs and longshyterm costs will be reduced

The cover system cap on Landfill Areas 3 and 4 covers an area of approximately 13 acres The cover system was designed to meet the performance requirements of the Resource Conservation and Recovery Act (RCRA) Subtitle C regulations and existing requirements of the Maine DEP and US EPA The cover system consists (from the bottom) of a base soil layer 9 inches of gas collection sand 24 inches of low-permeability soil (clay) a synthetic LLDPE 60 mil textured geomembrane 12 inches of drainage sand a geotextile fabric 12 to 18 inches of select borrow soil and 6 inches of topsoil with an erosion control blanket to control erosion before the vegetative grass cover becomes established The cover system also includes 20 passive gas vents surface water diversion benches perimeter ditches culverts and a stormwater management basin

The project was constructed as documented in the Final Completion of Removal Action Report which includes the record drawings the project specifications and the Construction Quality Assurance Plan These documents should be consulted for detailed information about the constructed systems Any work performed on the landfill site as described in this plan shall be performed under the direction of a City representative who is thoroughly familiar with this PRSC Plan the Completion of Removal Action Report and the Long-Term Monitoring Plan An archive copy of these three documents shall be maintained by the City of Saco and a working copy of the documents should be possessed by the City representative(s) who are responsible for the site operation and maintenance

2 RECORD KEEPING AND REPORTING

The PRSC activities shall be initiated upon completion of construction of the NTCRA Progress reports shall be submitted to the EPA and the Maine DEP throughout the period of the PRSC as described in this Plan and shall address each of the items that are identified in this Plan They will identify all of the

9606401 1 032699

PRSC activities that were performed since the previous PRSC Progress Report and those activities that will be performed in the time period until the next PRSC Progress Report The reports shall also include a summary of the results of any PRSC tests or evaluations completed since the last report and they shall identify any corrective measures that have been or need to be completed

Progress Reports shall be submitted three times per year for the first two years following approval of the PRSC Plan by EPA in June September and December for inspections conducted the previous month Inspections will be performed by a qualified Professional Engineer using the attached Inspection Record Form to ensure that all inspection items are addressed For the next eight years the PRSC Progress Reports shall be submitted in June and November of each year Thereafter Progress Reports shall be submitted annually in November

The site shall also be inspected after each significant weather event during the first two years of the post-removal monitoring program or for six months after a major re-vegetation activity (exceeding an area of 10000 square feet) A significant weather event is defined as 1-inch or more of rainfall in a 24 hour period The inspection may be performed by a qualified representative of the City of Saco and shall be documented on the Significant Weather Event form attached to this Plan If erosion is observed or if sediment containing run-off is entering Sandy Brook the US EPA and Maine DEP shall be notified immediately

Contact names addresses and phone numbers for reporting and emergency notification are as follows

Mr Edward Hathaway Mr Wilkes Harper USEPA Region 1 Maine Department of Environmental Protection 1 Congress Street Bureau of Remediation Suite 1100 (Mail code HBT) State House Station 17 Boston MA 02203-2211 Augusta ME 04333-0017 Phone 617-918-1372 Phoneshy 207-287-2651 Fax 617-918-1291 Fax 207-287-7826 Emergency ONLY (for uncontrolled releases spills Emergency Response ONLY (for uncontrolled or fires) 1-800-424-8802 releases spills or fires)- 1-800-482-0777

3 NORMAL OPERATIONS AND MAINTENANCE

Normal operations and maintenance for this site will consist primarily of landscaping care and site inspections The purpose of the maintenance program is to identify and correct any damage that may occur to the engineered systems at the site either by natural causes or by vandalism that could interfere with the proper functioning of these systems If damage is identified the cause of the damage shall be investigated and corrective maintenance or repairs shall be implemented

It is important to maintain and inspect the site so as to prevent more serious problems The grass must be mowed annually in order to prevent the growth of woody vegetation which could damage the cover system Erosion of soils could result in clogged drainage systems or exposure of the underlying geotextile or the geomembrane layers It is important that all drainage systems are operating properly in

9606401 2 OV2699

order to prevent saturation of soils Saturated soils are the most likely cause of slope failure resulting in expensive repairs and possible environmental damage

The normal landscaping care will include grass mowing drainage system cleaning and related maintenance Typical maintenance could include the repair of eroded soil or damaged drainage systems This work shall be the responsibility of the City of Saco In order to reduce potential impact to nesting birds the grass should be mowed only after July 15 each year The cut grass may either be left m place as mulch or removed Any thick deposits of cut grass mulch should be removed from the slope benches All normal maintenance activities including grass mowing shall be recorded on the Maintenance Record Form attached to this Plan

Animal borrows or other cover soil damage shall be repaired to the conditions of the surrounding areas Normal maintenance repairs are limited to the repair of the soil or channel surfaces to a depth of one foot from the constructed grade and these repairs can be made without specific written approval of the EPA No repairs shall be made to the geotextile fabric drainage sand geomembrane or underlying materials without specific written approval of the EPA

Significant accumulations of silt or debris that collects in the drainage systems must be removed All of the drainage channels are designed with freeboard above the flow depth of the 100-year frequency storm In the slope benches on the landfill cover the maximum allowable sediment depth is 6 inches above the surface of the rip-rap stone The allowable sediment depth in pipes and the flat bottom channels is 2 inches Any debris that restricts drainage flow shall be removed from drainage channels and structures The stone rip-rap linings of the drainage channels is provided to stabilize the surface from erosion when vegetation is not present Over time the rip-rap channels will accumulate soil material and may support the growth of grass and this is acceptable In fact the grass vegetation should provide some stormwater quality benefit

If normal maintenance requires the removal of sediment or debris from drainage channels or structures the work shall be performed with typical equipment used for the purpose taking care not to damage the surface of the cover system or any other site features and structures as part of the work In general the smallest equipment that will perform a specific task should be used to minimize potential damage to the facility If there is any possibility that damage was done to underlying cover materials or systems it shall be reported and investigated accordingly All normal maintenance activities shall be recorded on the Maintenance Record Form attached to this Plan

Inspections of the site shall be conducted by a qualified Professional Engineer within 30 days before the date of each Progress Report With one exception the inspections shall include all of the items identified in this Plan for regular monitoring The exception is that settlement monitoring will only be conducted annually for the November Progress Report Inspections shall include observations of the entire landfill cover system and the surrounding areas Each inspection shall be documented on the Inspection Record Form attached to this Plan Evaluations and assessments of the observed conditions shall be included in a letter report An outline of the report format is attached to this Plan

A copy of the record drawings and project specifications for the cover system construction shall be maintained by the City of Saco at the Public Works Department These documents shall be referenced whenever maintenance or inspections are performed A reduced copy of the record drawing As-Built

9606401 3 OV2699

Site Plan (attached as a Figure) shall be included with each inspection report in order to show the location of any identified problems or maintenance issues

4 OPERATIONAL SAFETY PLAN

All inspections and maintenance work at this site shall be performed in conformance with the Woodard amp Curran Health and Safety Plan (HASP) or another HASP that is at least as stringent as this one Requirements of the Occupational Safety and Health Act (OSHA) 29 CFR provide the basic safety requirements that shall be followed for all activities on the site

Although the possibility of exposure to hazardous chemicals is not anticipated all individuals at the site should be aware that the cover system is acting as a barrier to potentially hazardous materials buried m the landfill Any actions that could uncover these materials should be avoided If a condition is observed that indicate that potentially hazardous materials may be entering the environment the observation should be reported to the Maine DEP and the EPA

The more likely dangers at the site are accidents related to normal maintenance and inspection activities To prevent workplace accidents safety should be emphasized and practiced during all site activities The key to safety is good common sense Some guidelines for safety practices are the following

STOP AND THINK DOUBLE CHECK AVOID EXTREMES (such as overwork fatigue anger tension and haste)

Maintenance and inspection activities present many opportunities for physical injury to occur This site contains steep slopes and rip-rap drainage structures which could make otherwise normal activities more unpredictable and dangerous The use of equipment at this site should be done with particular care due to the special site conditions Wearing the proper protective clothing and sturdy boots and using common sense can prevent many injuries from occurring Appropriate gloves should be worn when handling materials or working on equipment It is noted that the landfill surface particularly the rip-rap stone channels may harbor bee or wasp nests Persons with an allergy to bee stings should take appropriate precautions

5 EVALUATION OF VEGETATIVE GROWTH EROSION AND OTHER SITE CONDITIONS

The condition of the vegetative growth and signs of erosion shall be evaluated after each inspection It is important for the grass to be kept mowed so that no woody plants become established The grass should be healthy and uniform The inspections should thorough observations of any unusual conditions such as areas where water does not drain wet or soft spots any bulges or depressions in the cover system and any signs of bulk soil movement or significant cracks Similar conditions should be identified in the stormwater management basin and in the areas surrounding the landfill cover system The inspections should also look for signs of improper uses of the site such as off-road vehicle use or other damage

9606401 4 032699

Wherever an area of poor grass growth is at least 100 square feet (10 by 10 or equivalent) the potential causes for this condition should be assessed If it is not due primarily to seasonal weather conditions (ie no ram) then further investigations should be performed to determine if fertilizer or other soil conditioners are necessary The investigations shall be designed to determine if the soil and nutrient conditions meet the requirements of the project specifications If discrete areas of the grass become stressed causes for this problem should be assessed and the problem corrected In general poor grass growth should be corrected by amending the soil as necessary and applying grass seed fertilizer and mulch as specified m the project specifications Section 02485 - Topsoil Seed and Mulch

Any areas of erosion shall be identified by the inspections and shown on the inspection Site Plan Normal maintenance shall be performed and documented in a Maintenance Record Form Any repair work shall be performed according to the requirements in the project specifications A recurring or major problem with erosion shall be addressed as described in the following section of this Plan

6 ASSESSMENT OF EROSION CONTROLS AND STORMWATER MANAGEMENT BASIN

The condition and performance of erosion control systems and the stormwater management basin shall be assessed after each inspection Even if all systems are operating properly normal maintenance will be required as noted in Section 3 of this Plan That section also identifies the depth of sediment that is allowable in the various drainage channels and the procedures for cleaning However if there is evidence of poor performance or damage to systems it is necessary to review the adequacy of the erosion control features Poor performance could include the recurrence of sedimentation m specific places or recurring damage to systems that require repairs In such cases an assessment of the problem shall be performed and a solution identified and implemented

The stormwater management basin is intended to control the rate of runoff from the site by limiting the flow from the basin to a pre-development rate of flow that is much less than the instantaneous runoff rate from the landfill cover area It is anticipated that the lower elevations of the basin along the berm on the east side will have a ground surface condition that is usually wet allowing wetland vegetation to become established This is normal operation and is acceptable The basin should be inspected for any obvious structural or erosion damage and the outlet structure should be inspected for proper operation If damage or clogging is identified the improper conditions shall be corrected in accordance with the record drawings and the project specifications including Section 02715 - Site Piping If sediments reach a depth of 6 inches they shall be removed during dry conditions The removal of sediments shall be performed with tracked equipment that limits the compaction of the soils and quality assurance shall be provided by observation and inspection of the repair activity All maintenance and repair activity shall be recorded on the Maintenance Record Form attached to this Plan

It is noted that groundwater from the closed landfill on the north side of Sandy Brook is proposed to be treated and pumped into Culvert 3 and will then enter the northern end of the stormwater management basin This flow will be a relatively small quantity compared to storm flow quantities so most of this water will enter the wet pool in the stormwater basin and infiltrate into the groundwater

9606401 5 012699

7 POTENTIAL PROBLEMS AND CONTINGENCY PLAN

A number of the potential problems that could occur to the landfill cover system at the site have been identified along with the appropriate contingency response Some items are considered normal maintenance activities as noted previously while some are major repairs that must be performed by a specialty contractor after approval by the EPA Work that can be performed without the specific approval of the EPA includes any maintenance and repair to the cover and slope benches to a depth of one foot below the constructed surface grade or any repairs beyond the limits of the cover system In any case all repairs shall be performed in accordance with the record drawings and project specifications including the quality controlquality assurance procedures These potential problems and responses are summarized in the table on the next page

While unlikely a more severe problem could occur A severe problem could result from an earthquake a failure of the constructed cover system due to other causes or a release of contaminants into the environment In such a case the inspector should immediately notify the EPA and the DEP and engage a qualified Professional Engineer in order to develop a more detailed and appropriate response

Potential Problem Contingency Response 1 Erosion of surface soil Identify the cause of the erosion if possible and

eliminaterepair it Place new soil in any gullies spread topsoil seed and heavy mulch

2 Sedimentation in drainage channels or pipes Identify the sourcecause of the sedimentation if possible and correct it Remove the sediment to maintain full capacity of the structures

3 Erosion in drainage channels or damage to Identify the cause of the problem if possible and pipes eliminaterepair it Place new rip-rap (and repair

gabions) in any eroded channels install topsoil seed and heavy mulch as necessary Damaged pipes shall be repaired to their original condition

4 Damaged gas vent riser pipe Repair damaged pipe as appropriate Holes smaller than 1-inch diameter can be patched any larger holes or a broken pipe must be cut and fusion-welded by a qualified contractor

5 Differential settlement of cover system Some differential settlement is expected but if drainage is impaired andor water is ponding on the cover surface (or in drainage channels) proper drainage must be restored The initial response shall be to fill depressions with soil or repair drainage channels to drain The cause of the drainage problem shall be assessed in the following Progress Report If repairs to the underlying membrane system are recommended they shall be approved by the EPA before proceeding

96064 01 032699

Potential Problem Contingency Response 6 Soil movement that exposes geomembrane Any significant soil movement or other cause that

(Or other obvious damage to the exposes the geomembrane shall be investigated geomembrane) and assessed in the following Progress Report An

initial response shall be as appropriate to control further damage to the cover system If repairs to the underlying geomembrane system are necessary they shall be approved by the EPA before proceeding

8 EVALUATION OF STABILITY

The stability of the site shall be qualitatively assessed after each inspection Indications of unstable soil and cover system conditions could include longitudinal cracks or depressions in the soil surface or evidence of slumping or impaired drainage at the lower areas of slopes or in drainage channels If either of these conditions are identified additional investigations should be performed to determine if site or slope stability may be impaired At a minimum the identified area of surface depression should be surveyed at the time that settlement monitoring is performed Surveys should then be performed annually to monitor for changes over time The procedures listed in Section 12 of this Plan should be followed for further analysis

The gabion wall at the entrance to Culvert 1 on the eastern side of the landfill should be monitored for tilt as an indication of slope stability The specific location for measuring the tilt is described on the Inspection Record Form attached to this Plan Any changes in tilt of the wall should be identified in the Progress Reports and the implications on stability shall be qualitatively assessed

9 ASSESSMENT OF PASSIVE GAS VENTING SYSTEM

The condition and performance of the passive gas venting system shall be qualitatively assessed after each inspection The condition of the gas vents will be determined by visual observation of the gas vent risers and the adjacent cover surface conditions The vents should be protruding from the cover system with the outlet at least 7 feet above the cover surface (Some leaning of the HDPE pipes is expected) The screens should be in place on the ends of the pipes Where the pipe boots are visible there should be no signs of damage The surrounding soil should be firmly supporting the riser pipe with no voids or spaces that could indicate movement of the riser or adjacent soil If any improper conditions are observed additional investigations should be performed to determine if there is damage to the vent structure that requires repairs

Signs of poor performance would include a clogged gas vent screen or an indication that gas is releasing through or beyond the cover system This condition is usually indicated by stress in the vegetation that can not otherwise be explained If this is the case additional investigations should be performed to determine if gas is not being properly vented and if further repairs or improvements are required

96064 01 0326 99

As an indication of gas vent physical conditions over time the tilt or lean of each gas vent riser should be measured annually during the inspection prior to the NovemberDecember Progress Report As part of the inspection report the data shall be compared to the baseline data from previous inspections A variation of about 2 inches in the angle measurement is expected to occur from variations m temperature and measurement accuracy If any of the gas vents exhibit an unusual change in the tilt angle (more than 3 inches from the previous condition) they should be investigated in more detail during the following inspections

10 EVALUATION OF SANDY BROOK SEDIMENT REMOVAL AREA

The Sandy Brook Sediment Removal Area is located to the north of monitoring well MW-95-4 and is noted as Seep Area on the record drawing Site Plan It is an area that had previously been a depression in the ground next to Sandy Brook The area contained contaminated sediments that have been removed and the area has been filled with soil

The conditions at the Sandy Brook Sediment Removal Area shall be evaluated after each inspection The inspection shall look for evidence of discoloration (ie iron staining) erosion from surface drainage or from high levels of flow in the Brook that could result in a sediment discharge to the Brook Any identified problems shall be repaired to prevent potential impacts to the Brook Repairs shall consist of filling and erosion control construction in accordance with the project specifications

11 IMPACT ON WETLANDS

The impact on the surrounding wetlands shall be evaluated in accordance with the wetlands restoration monitoring plan that has not been developed at the time this PRSC Plan was prepared It is anticipated that the wetlands inspections will be conducted at the same time as the normal site inspections but this will need to be refined and clarified in the wetlands monitoring plan The correction of any identified impact needs to be evaluated and approved by the EPA before any action is implemented

12 SETTLEMENT MONITORING

Settlement of the cover system is expected to occur over time as the waste material continues to decompose This anticipated settlement results in a relatively uniform subsidence of the ground surface is not expected to damage the cover system It is differential settlement that is undesirable because it could damage the cover system and this differential settlement will be identified by problems with surface drainage or by general observations of surface conditions However overall settlement of the landfill will be monitored in order to document the rate and magnitude of settlement The monitoring will occur m the fall of each year and will be reported in the NovemberDecember Progress Report

Settlement monitoring will be conducted by measuring the elevations of monitoring points established on each of four gas vents numbers 7 8 9 and 10 These are the vents located along the highest profile of the landfill and will therefore measure the areas where the greatest settlement is expected The gas vents

9606401 8 OV26 99

only penetrate into the waste about 5 feet so they accurately reflect the elevation and settlement of the landfill surface

If the landfill inspections identify an area with a depression on the surface of the cover system where water does not drain properly or if an area larger than 400 square feet (20 feet by 20 feet or equivalent) has settled by more than 1 foot from the adjacent proper elevations the area needs to be documented and monitored At a minimum the location and elevations of the surface depression should be surveyed at the time that settlement monitoring is performed Surveys should then be performed annually to monitor for changes over time If an area is repaired by filling a depression and it does not continue to settle for the next two years of surveys the annual surveying can be discontinued If a depression is filled and continues to settle after two years the area shall be evaluated to determine if the mobilized tensile stress in the geomembrane exceeds allowable values If it does a geomembrane investigation plan shall be recommended in the monitoring report and the plan shall be approved by the EPA before it is performed

9606401 9 032699

Outline of Sample Progress Report Post-Removal Site Control Plan Saco Municipal Landfill Closure

Saco Maine

1 Summary of PRSC activities that have occurred since last report

2 Summary and evaluation of cover system inspection results bull Identify critical issues or problems bull Characterize performance of vegetative growth and erosion controls Determine if poor

growth or erosion is occurring in particular locations bull Characterize the performance of slope benches and rip-rap downdrains bull Assess the significance of any identified drainage problems soft or wet areas or other

cover system damage bull Assess the performance of the gas venting system bull Characterize the performance of the perimeter drainage zone and outlet pipes

3 Summary and evaluation of conditions outside the limits of the cover system bull Identify critical issues or problems including any indications of leachate seeps bull Characterize the performance of the gabion structure at inlet to Culvert 1 bull Characterize performance of perimeter drainage channels and erosion controls bull Determine if poor growth or erosion is occurring in particular locations bull Assess the condition of the culverts manholes and the rip-rap oulet plunge pools bull Assess the condition and performance of the stormwater detention basin

4 Assess the site and slope stability based on qualitative data

5 Evaluate the conditions at the Sandy Brook Sediment Removal Area Identify problems that should be repaired in order to prevent a sediment discharge to Sandy Brook

6 Identify and evaluate any potential impacts on the surrounding wetlands in accordance with the wetlands monitoring plan once it is developed

7 Summary of the results of settlement monitoring over the post closure period

8 Summarize results of Significant Weather event reports

9 Recommend actions and maintenance activities to occur before the next inspection

Appendices Maintenance Reports Inspection Reports Significant Weather Event Reports

FIGURES

95093 14 DRAF F 012699

MONITORING FORMS

9509314 DRAFT 032filtraquo

PRSC activities that were performed since the previous PRSC Progress Report and those activities that will be performed in the time period until the next PRSC Progress Report The reports shall also include a summary of the results of any PRSC tests or evaluations completed since the last report and they shall identify any corrective measures that have been or need to be completed

Progress Reports shall be submitted three times per year for the first two years following approval of the PRSC Plan by EPA in June September and December for inspections conducted the previous month Inspections will be performed by a qualified Professional Engineer using the attached Inspection Record Form to ensure that all inspection items are addressed For the next eight years the PRSC Progress Reports shall be submitted in June and November of each year Thereafter Progress Reports shall be submitted annually in November

The site shall also be inspected after each significant weather event during the first two years of the post-removal monitoring program or for six months after a major re-vegetation activity (exceeding an area of 10000 square feet) A significant weather event is defined as 1-inch or more of rainfall in a 24 hour period The inspection may be performed by a qualified representative of the City of Saco and shall be documented on the Significant Weather Event form attached to this Plan If erosion is observed or if sediment containing run-off is entering Sandy Brook the US EPA and Maine DEP shall be notified immediately

Contact names addresses and phone numbers for reporting and emergency notification are as follows

Mr Edward Hathaway Mr Wilkes Harper USEPA Region 1 Maine Department of Environmental Protection 1 Congress Street Bureau of Remediation Suite 1100 (Mail code HBT) State House Station 17 Boston MA 02203-2211 Augusta ME 04333-0017 Phone 617-918-1372 Phoneshy 207-287-2651 Fax 617-918-1291 Fax 207-287-7826 Emergency ONLY (for uncontrolled releases spills Emergency Response ONLY (for uncontrolled or fires) 1-800-424-8802 releases spills or fires)- 1-800-482-0777

3 NORMAL OPERATIONS AND MAINTENANCE

Normal operations and maintenance for this site will consist primarily of landscaping care and site inspections The purpose of the maintenance program is to identify and correct any damage that may occur to the engineered systems at the site either by natural causes or by vandalism that could interfere with the proper functioning of these systems If damage is identified the cause of the damage shall be investigated and corrective maintenance or repairs shall be implemented

It is important to maintain and inspect the site so as to prevent more serious problems The grass must be mowed annually in order to prevent the growth of woody vegetation which could damage the cover system Erosion of soils could result in clogged drainage systems or exposure of the underlying geotextile or the geomembrane layers It is important that all drainage systems are operating properly in

9606401 2 OV2699

order to prevent saturation of soils Saturated soils are the most likely cause of slope failure resulting in expensive repairs and possible environmental damage

The normal landscaping care will include grass mowing drainage system cleaning and related maintenance Typical maintenance could include the repair of eroded soil or damaged drainage systems This work shall be the responsibility of the City of Saco In order to reduce potential impact to nesting birds the grass should be mowed only after July 15 each year The cut grass may either be left m place as mulch or removed Any thick deposits of cut grass mulch should be removed from the slope benches All normal maintenance activities including grass mowing shall be recorded on the Maintenance Record Form attached to this Plan

Animal borrows or other cover soil damage shall be repaired to the conditions of the surrounding areas Normal maintenance repairs are limited to the repair of the soil or channel surfaces to a depth of one foot from the constructed grade and these repairs can be made without specific written approval of the EPA No repairs shall be made to the geotextile fabric drainage sand geomembrane or underlying materials without specific written approval of the EPA

Significant accumulations of silt or debris that collects in the drainage systems must be removed All of the drainage channels are designed with freeboard above the flow depth of the 100-year frequency storm In the slope benches on the landfill cover the maximum allowable sediment depth is 6 inches above the surface of the rip-rap stone The allowable sediment depth in pipes and the flat bottom channels is 2 inches Any debris that restricts drainage flow shall be removed from drainage channels and structures The stone rip-rap linings of the drainage channels is provided to stabilize the surface from erosion when vegetation is not present Over time the rip-rap channels will accumulate soil material and may support the growth of grass and this is acceptable In fact the grass vegetation should provide some stormwater quality benefit

If normal maintenance requires the removal of sediment or debris from drainage channels or structures the work shall be performed with typical equipment used for the purpose taking care not to damage the surface of the cover system or any other site features and structures as part of the work In general the smallest equipment that will perform a specific task should be used to minimize potential damage to the facility If there is any possibility that damage was done to underlying cover materials or systems it shall be reported and investigated accordingly All normal maintenance activities shall be recorded on the Maintenance Record Form attached to this Plan

Inspections of the site shall be conducted by a qualified Professional Engineer within 30 days before the date of each Progress Report With one exception the inspections shall include all of the items identified in this Plan for regular monitoring The exception is that settlement monitoring will only be conducted annually for the November Progress Report Inspections shall include observations of the entire landfill cover system and the surrounding areas Each inspection shall be documented on the Inspection Record Form attached to this Plan Evaluations and assessments of the observed conditions shall be included in a letter report An outline of the report format is attached to this Plan

A copy of the record drawings and project specifications for the cover system construction shall be maintained by the City of Saco at the Public Works Department These documents shall be referenced whenever maintenance or inspections are performed A reduced copy of the record drawing As-Built

9606401 3 OV2699

Site Plan (attached as a Figure) shall be included with each inspection report in order to show the location of any identified problems or maintenance issues

4 OPERATIONAL SAFETY PLAN

All inspections and maintenance work at this site shall be performed in conformance with the Woodard amp Curran Health and Safety Plan (HASP) or another HASP that is at least as stringent as this one Requirements of the Occupational Safety and Health Act (OSHA) 29 CFR provide the basic safety requirements that shall be followed for all activities on the site

Although the possibility of exposure to hazardous chemicals is not anticipated all individuals at the site should be aware that the cover system is acting as a barrier to potentially hazardous materials buried m the landfill Any actions that could uncover these materials should be avoided If a condition is observed that indicate that potentially hazardous materials may be entering the environment the observation should be reported to the Maine DEP and the EPA

The more likely dangers at the site are accidents related to normal maintenance and inspection activities To prevent workplace accidents safety should be emphasized and practiced during all site activities The key to safety is good common sense Some guidelines for safety practices are the following

STOP AND THINK DOUBLE CHECK AVOID EXTREMES (such as overwork fatigue anger tension and haste)

Maintenance and inspection activities present many opportunities for physical injury to occur This site contains steep slopes and rip-rap drainage structures which could make otherwise normal activities more unpredictable and dangerous The use of equipment at this site should be done with particular care due to the special site conditions Wearing the proper protective clothing and sturdy boots and using common sense can prevent many injuries from occurring Appropriate gloves should be worn when handling materials or working on equipment It is noted that the landfill surface particularly the rip-rap stone channels may harbor bee or wasp nests Persons with an allergy to bee stings should take appropriate precautions

5 EVALUATION OF VEGETATIVE GROWTH EROSION AND OTHER SITE CONDITIONS

The condition of the vegetative growth and signs of erosion shall be evaluated after each inspection It is important for the grass to be kept mowed so that no woody plants become established The grass should be healthy and uniform The inspections should thorough observations of any unusual conditions such as areas where water does not drain wet or soft spots any bulges or depressions in the cover system and any signs of bulk soil movement or significant cracks Similar conditions should be identified in the stormwater management basin and in the areas surrounding the landfill cover system The inspections should also look for signs of improper uses of the site such as off-road vehicle use or other damage

9606401 4 032699

Wherever an area of poor grass growth is at least 100 square feet (10 by 10 or equivalent) the potential causes for this condition should be assessed If it is not due primarily to seasonal weather conditions (ie no ram) then further investigations should be performed to determine if fertilizer or other soil conditioners are necessary The investigations shall be designed to determine if the soil and nutrient conditions meet the requirements of the project specifications If discrete areas of the grass become stressed causes for this problem should be assessed and the problem corrected In general poor grass growth should be corrected by amending the soil as necessary and applying grass seed fertilizer and mulch as specified m the project specifications Section 02485 - Topsoil Seed and Mulch

Any areas of erosion shall be identified by the inspections and shown on the inspection Site Plan Normal maintenance shall be performed and documented in a Maintenance Record Form Any repair work shall be performed according to the requirements in the project specifications A recurring or major problem with erosion shall be addressed as described in the following section of this Plan

6 ASSESSMENT OF EROSION CONTROLS AND STORMWATER MANAGEMENT BASIN

The condition and performance of erosion control systems and the stormwater management basin shall be assessed after each inspection Even if all systems are operating properly normal maintenance will be required as noted in Section 3 of this Plan That section also identifies the depth of sediment that is allowable in the various drainage channels and the procedures for cleaning However if there is evidence of poor performance or damage to systems it is necessary to review the adequacy of the erosion control features Poor performance could include the recurrence of sedimentation m specific places or recurring damage to systems that require repairs In such cases an assessment of the problem shall be performed and a solution identified and implemented

The stormwater management basin is intended to control the rate of runoff from the site by limiting the flow from the basin to a pre-development rate of flow that is much less than the instantaneous runoff rate from the landfill cover area It is anticipated that the lower elevations of the basin along the berm on the east side will have a ground surface condition that is usually wet allowing wetland vegetation to become established This is normal operation and is acceptable The basin should be inspected for any obvious structural or erosion damage and the outlet structure should be inspected for proper operation If damage or clogging is identified the improper conditions shall be corrected in accordance with the record drawings and the project specifications including Section 02715 - Site Piping If sediments reach a depth of 6 inches they shall be removed during dry conditions The removal of sediments shall be performed with tracked equipment that limits the compaction of the soils and quality assurance shall be provided by observation and inspection of the repair activity All maintenance and repair activity shall be recorded on the Maintenance Record Form attached to this Plan

It is noted that groundwater from the closed landfill on the north side of Sandy Brook is proposed to be treated and pumped into Culvert 3 and will then enter the northern end of the stormwater management basin This flow will be a relatively small quantity compared to storm flow quantities so most of this water will enter the wet pool in the stormwater basin and infiltrate into the groundwater

9606401 5 012699

7 POTENTIAL PROBLEMS AND CONTINGENCY PLAN

A number of the potential problems that could occur to the landfill cover system at the site have been identified along with the appropriate contingency response Some items are considered normal maintenance activities as noted previously while some are major repairs that must be performed by a specialty contractor after approval by the EPA Work that can be performed without the specific approval of the EPA includes any maintenance and repair to the cover and slope benches to a depth of one foot below the constructed surface grade or any repairs beyond the limits of the cover system In any case all repairs shall be performed in accordance with the record drawings and project specifications including the quality controlquality assurance procedures These potential problems and responses are summarized in the table on the next page

While unlikely a more severe problem could occur A severe problem could result from an earthquake a failure of the constructed cover system due to other causes or a release of contaminants into the environment In such a case the inspector should immediately notify the EPA and the DEP and engage a qualified Professional Engineer in order to develop a more detailed and appropriate response

Potential Problem Contingency Response 1 Erosion of surface soil Identify the cause of the erosion if possible and

eliminaterepair it Place new soil in any gullies spread topsoil seed and heavy mulch

2 Sedimentation in drainage channels or pipes Identify the sourcecause of the sedimentation if possible and correct it Remove the sediment to maintain full capacity of the structures

3 Erosion in drainage channels or damage to Identify the cause of the problem if possible and pipes eliminaterepair it Place new rip-rap (and repair

gabions) in any eroded channels install topsoil seed and heavy mulch as necessary Damaged pipes shall be repaired to their original condition

4 Damaged gas vent riser pipe Repair damaged pipe as appropriate Holes smaller than 1-inch diameter can be patched any larger holes or a broken pipe must be cut and fusion-welded by a qualified contractor

5 Differential settlement of cover system Some differential settlement is expected but if drainage is impaired andor water is ponding on the cover surface (or in drainage channels) proper drainage must be restored The initial response shall be to fill depressions with soil or repair drainage channels to drain The cause of the drainage problem shall be assessed in the following Progress Report If repairs to the underlying membrane system are recommended they shall be approved by the EPA before proceeding

96064 01 032699

Potential Problem Contingency Response 6 Soil movement that exposes geomembrane Any significant soil movement or other cause that

(Or other obvious damage to the exposes the geomembrane shall be investigated geomembrane) and assessed in the following Progress Report An

initial response shall be as appropriate to control further damage to the cover system If repairs to the underlying geomembrane system are necessary they shall be approved by the EPA before proceeding

8 EVALUATION OF STABILITY

The stability of the site shall be qualitatively assessed after each inspection Indications of unstable soil and cover system conditions could include longitudinal cracks or depressions in the soil surface or evidence of slumping or impaired drainage at the lower areas of slopes or in drainage channels If either of these conditions are identified additional investigations should be performed to determine if site or slope stability may be impaired At a minimum the identified area of surface depression should be surveyed at the time that settlement monitoring is performed Surveys should then be performed annually to monitor for changes over time The procedures listed in Section 12 of this Plan should be followed for further analysis

The gabion wall at the entrance to Culvert 1 on the eastern side of the landfill should be monitored for tilt as an indication of slope stability The specific location for measuring the tilt is described on the Inspection Record Form attached to this Plan Any changes in tilt of the wall should be identified in the Progress Reports and the implications on stability shall be qualitatively assessed

9 ASSESSMENT OF PASSIVE GAS VENTING SYSTEM

The condition and performance of the passive gas venting system shall be qualitatively assessed after each inspection The condition of the gas vents will be determined by visual observation of the gas vent risers and the adjacent cover surface conditions The vents should be protruding from the cover system with the outlet at least 7 feet above the cover surface (Some leaning of the HDPE pipes is expected) The screens should be in place on the ends of the pipes Where the pipe boots are visible there should be no signs of damage The surrounding soil should be firmly supporting the riser pipe with no voids or spaces that could indicate movement of the riser or adjacent soil If any improper conditions are observed additional investigations should be performed to determine if there is damage to the vent structure that requires repairs

Signs of poor performance would include a clogged gas vent screen or an indication that gas is releasing through or beyond the cover system This condition is usually indicated by stress in the vegetation that can not otherwise be explained If this is the case additional investigations should be performed to determine if gas is not being properly vented and if further repairs or improvements are required

96064 01 0326 99

As an indication of gas vent physical conditions over time the tilt or lean of each gas vent riser should be measured annually during the inspection prior to the NovemberDecember Progress Report As part of the inspection report the data shall be compared to the baseline data from previous inspections A variation of about 2 inches in the angle measurement is expected to occur from variations m temperature and measurement accuracy If any of the gas vents exhibit an unusual change in the tilt angle (more than 3 inches from the previous condition) they should be investigated in more detail during the following inspections

10 EVALUATION OF SANDY BROOK SEDIMENT REMOVAL AREA

The Sandy Brook Sediment Removal Area is located to the north of monitoring well MW-95-4 and is noted as Seep Area on the record drawing Site Plan It is an area that had previously been a depression in the ground next to Sandy Brook The area contained contaminated sediments that have been removed and the area has been filled with soil

The conditions at the Sandy Brook Sediment Removal Area shall be evaluated after each inspection The inspection shall look for evidence of discoloration (ie iron staining) erosion from surface drainage or from high levels of flow in the Brook that could result in a sediment discharge to the Brook Any identified problems shall be repaired to prevent potential impacts to the Brook Repairs shall consist of filling and erosion control construction in accordance with the project specifications

11 IMPACT ON WETLANDS

The impact on the surrounding wetlands shall be evaluated in accordance with the wetlands restoration monitoring plan that has not been developed at the time this PRSC Plan was prepared It is anticipated that the wetlands inspections will be conducted at the same time as the normal site inspections but this will need to be refined and clarified in the wetlands monitoring plan The correction of any identified impact needs to be evaluated and approved by the EPA before any action is implemented

12 SETTLEMENT MONITORING

Settlement of the cover system is expected to occur over time as the waste material continues to decompose This anticipated settlement results in a relatively uniform subsidence of the ground surface is not expected to damage the cover system It is differential settlement that is undesirable because it could damage the cover system and this differential settlement will be identified by problems with surface drainage or by general observations of surface conditions However overall settlement of the landfill will be monitored in order to document the rate and magnitude of settlement The monitoring will occur m the fall of each year and will be reported in the NovemberDecember Progress Report

Settlement monitoring will be conducted by measuring the elevations of monitoring points established on each of four gas vents numbers 7 8 9 and 10 These are the vents located along the highest profile of the landfill and will therefore measure the areas where the greatest settlement is expected The gas vents

9606401 8 OV26 99

only penetrate into the waste about 5 feet so they accurately reflect the elevation and settlement of the landfill surface

If the landfill inspections identify an area with a depression on the surface of the cover system where water does not drain properly or if an area larger than 400 square feet (20 feet by 20 feet or equivalent) has settled by more than 1 foot from the adjacent proper elevations the area needs to be documented and monitored At a minimum the location and elevations of the surface depression should be surveyed at the time that settlement monitoring is performed Surveys should then be performed annually to monitor for changes over time If an area is repaired by filling a depression and it does not continue to settle for the next two years of surveys the annual surveying can be discontinued If a depression is filled and continues to settle after two years the area shall be evaluated to determine if the mobilized tensile stress in the geomembrane exceeds allowable values If it does a geomembrane investigation plan shall be recommended in the monitoring report and the plan shall be approved by the EPA before it is performed

9606401 9 032699

Outline of Sample Progress Report Post-Removal Site Control Plan Saco Municipal Landfill Closure

Saco Maine

1 Summary of PRSC activities that have occurred since last report

2 Summary and evaluation of cover system inspection results bull Identify critical issues or problems bull Characterize performance of vegetative growth and erosion controls Determine if poor

growth or erosion is occurring in particular locations bull Characterize the performance of slope benches and rip-rap downdrains bull Assess the significance of any identified drainage problems soft or wet areas or other

cover system damage bull Assess the performance of the gas venting system bull Characterize the performance of the perimeter drainage zone and outlet pipes

3 Summary and evaluation of conditions outside the limits of the cover system bull Identify critical issues or problems including any indications of leachate seeps bull Characterize the performance of the gabion structure at inlet to Culvert 1 bull Characterize performance of perimeter drainage channels and erosion controls bull Determine if poor growth or erosion is occurring in particular locations bull Assess the condition of the culverts manholes and the rip-rap oulet plunge pools bull Assess the condition and performance of the stormwater detention basin

4 Assess the site and slope stability based on qualitative data

5 Evaluate the conditions at the Sandy Brook Sediment Removal Area Identify problems that should be repaired in order to prevent a sediment discharge to Sandy Brook

6 Identify and evaluate any potential impacts on the surrounding wetlands in accordance with the wetlands monitoring plan once it is developed

7 Summary of the results of settlement monitoring over the post closure period

8 Summarize results of Significant Weather event reports

9 Recommend actions and maintenance activities to occur before the next inspection

Appendices Maintenance Reports Inspection Reports Significant Weather Event Reports

FIGURES

95093 14 DRAF F 012699

MONITORING FORMS

9509314 DRAFT 032filtraquo

order to prevent saturation of soils Saturated soils are the most likely cause of slope failure resulting in expensive repairs and possible environmental damage

The normal landscaping care will include grass mowing drainage system cleaning and related maintenance Typical maintenance could include the repair of eroded soil or damaged drainage systems This work shall be the responsibility of the City of Saco In order to reduce potential impact to nesting birds the grass should be mowed only after July 15 each year The cut grass may either be left m place as mulch or removed Any thick deposits of cut grass mulch should be removed from the slope benches All normal maintenance activities including grass mowing shall be recorded on the Maintenance Record Form attached to this Plan

Animal borrows or other cover soil damage shall be repaired to the conditions of the surrounding areas Normal maintenance repairs are limited to the repair of the soil or channel surfaces to a depth of one foot from the constructed grade and these repairs can be made without specific written approval of the EPA No repairs shall be made to the geotextile fabric drainage sand geomembrane or underlying materials without specific written approval of the EPA

Significant accumulations of silt or debris that collects in the drainage systems must be removed All of the drainage channels are designed with freeboard above the flow depth of the 100-year frequency storm In the slope benches on the landfill cover the maximum allowable sediment depth is 6 inches above the surface of the rip-rap stone The allowable sediment depth in pipes and the flat bottom channels is 2 inches Any debris that restricts drainage flow shall be removed from drainage channels and structures The stone rip-rap linings of the drainage channels is provided to stabilize the surface from erosion when vegetation is not present Over time the rip-rap channels will accumulate soil material and may support the growth of grass and this is acceptable In fact the grass vegetation should provide some stormwater quality benefit

If normal maintenance requires the removal of sediment or debris from drainage channels or structures the work shall be performed with typical equipment used for the purpose taking care not to damage the surface of the cover system or any other site features and structures as part of the work In general the smallest equipment that will perform a specific task should be used to minimize potential damage to the facility If there is any possibility that damage was done to underlying cover materials or systems it shall be reported and investigated accordingly All normal maintenance activities shall be recorded on the Maintenance Record Form attached to this Plan

Inspections of the site shall be conducted by a qualified Professional Engineer within 30 days before the date of each Progress Report With one exception the inspections shall include all of the items identified in this Plan for regular monitoring The exception is that settlement monitoring will only be conducted annually for the November Progress Report Inspections shall include observations of the entire landfill cover system and the surrounding areas Each inspection shall be documented on the Inspection Record Form attached to this Plan Evaluations and assessments of the observed conditions shall be included in a letter report An outline of the report format is attached to this Plan

A copy of the record drawings and project specifications for the cover system construction shall be maintained by the City of Saco at the Public Works Department These documents shall be referenced whenever maintenance or inspections are performed A reduced copy of the record drawing As-Built

9606401 3 OV2699

Site Plan (attached as a Figure) shall be included with each inspection report in order to show the location of any identified problems or maintenance issues

4 OPERATIONAL SAFETY PLAN

All inspections and maintenance work at this site shall be performed in conformance with the Woodard amp Curran Health and Safety Plan (HASP) or another HASP that is at least as stringent as this one Requirements of the Occupational Safety and Health Act (OSHA) 29 CFR provide the basic safety requirements that shall be followed for all activities on the site

Although the possibility of exposure to hazardous chemicals is not anticipated all individuals at the site should be aware that the cover system is acting as a barrier to potentially hazardous materials buried m the landfill Any actions that could uncover these materials should be avoided If a condition is observed that indicate that potentially hazardous materials may be entering the environment the observation should be reported to the Maine DEP and the EPA

The more likely dangers at the site are accidents related to normal maintenance and inspection activities To prevent workplace accidents safety should be emphasized and practiced during all site activities The key to safety is good common sense Some guidelines for safety practices are the following

STOP AND THINK DOUBLE CHECK AVOID EXTREMES (such as overwork fatigue anger tension and haste)

Maintenance and inspection activities present many opportunities for physical injury to occur This site contains steep slopes and rip-rap drainage structures which could make otherwise normal activities more unpredictable and dangerous The use of equipment at this site should be done with particular care due to the special site conditions Wearing the proper protective clothing and sturdy boots and using common sense can prevent many injuries from occurring Appropriate gloves should be worn when handling materials or working on equipment It is noted that the landfill surface particularly the rip-rap stone channels may harbor bee or wasp nests Persons with an allergy to bee stings should take appropriate precautions

5 EVALUATION OF VEGETATIVE GROWTH EROSION AND OTHER SITE CONDITIONS

The condition of the vegetative growth and signs of erosion shall be evaluated after each inspection It is important for the grass to be kept mowed so that no woody plants become established The grass should be healthy and uniform The inspections should thorough observations of any unusual conditions such as areas where water does not drain wet or soft spots any bulges or depressions in the cover system and any signs of bulk soil movement or significant cracks Similar conditions should be identified in the stormwater management basin and in the areas surrounding the landfill cover system The inspections should also look for signs of improper uses of the site such as off-road vehicle use or other damage

9606401 4 032699

Wherever an area of poor grass growth is at least 100 square feet (10 by 10 or equivalent) the potential causes for this condition should be assessed If it is not due primarily to seasonal weather conditions (ie no ram) then further investigations should be performed to determine if fertilizer or other soil conditioners are necessary The investigations shall be designed to determine if the soil and nutrient conditions meet the requirements of the project specifications If discrete areas of the grass become stressed causes for this problem should be assessed and the problem corrected In general poor grass growth should be corrected by amending the soil as necessary and applying grass seed fertilizer and mulch as specified m the project specifications Section 02485 - Topsoil Seed and Mulch

Any areas of erosion shall be identified by the inspections and shown on the inspection Site Plan Normal maintenance shall be performed and documented in a Maintenance Record Form Any repair work shall be performed according to the requirements in the project specifications A recurring or major problem with erosion shall be addressed as described in the following section of this Plan

6 ASSESSMENT OF EROSION CONTROLS AND STORMWATER MANAGEMENT BASIN

The condition and performance of erosion control systems and the stormwater management basin shall be assessed after each inspection Even if all systems are operating properly normal maintenance will be required as noted in Section 3 of this Plan That section also identifies the depth of sediment that is allowable in the various drainage channels and the procedures for cleaning However if there is evidence of poor performance or damage to systems it is necessary to review the adequacy of the erosion control features Poor performance could include the recurrence of sedimentation m specific places or recurring damage to systems that require repairs In such cases an assessment of the problem shall be performed and a solution identified and implemented

The stormwater management basin is intended to control the rate of runoff from the site by limiting the flow from the basin to a pre-development rate of flow that is much less than the instantaneous runoff rate from the landfill cover area It is anticipated that the lower elevations of the basin along the berm on the east side will have a ground surface condition that is usually wet allowing wetland vegetation to become established This is normal operation and is acceptable The basin should be inspected for any obvious structural or erosion damage and the outlet structure should be inspected for proper operation If damage or clogging is identified the improper conditions shall be corrected in accordance with the record drawings and the project specifications including Section 02715 - Site Piping If sediments reach a depth of 6 inches they shall be removed during dry conditions The removal of sediments shall be performed with tracked equipment that limits the compaction of the soils and quality assurance shall be provided by observation and inspection of the repair activity All maintenance and repair activity shall be recorded on the Maintenance Record Form attached to this Plan

It is noted that groundwater from the closed landfill on the north side of Sandy Brook is proposed to be treated and pumped into Culvert 3 and will then enter the northern end of the stormwater management basin This flow will be a relatively small quantity compared to storm flow quantities so most of this water will enter the wet pool in the stormwater basin and infiltrate into the groundwater

9606401 5 012699

7 POTENTIAL PROBLEMS AND CONTINGENCY PLAN

A number of the potential problems that could occur to the landfill cover system at the site have been identified along with the appropriate contingency response Some items are considered normal maintenance activities as noted previously while some are major repairs that must be performed by a specialty contractor after approval by the EPA Work that can be performed without the specific approval of the EPA includes any maintenance and repair to the cover and slope benches to a depth of one foot below the constructed surface grade or any repairs beyond the limits of the cover system In any case all repairs shall be performed in accordance with the record drawings and project specifications including the quality controlquality assurance procedures These potential problems and responses are summarized in the table on the next page

While unlikely a more severe problem could occur A severe problem could result from an earthquake a failure of the constructed cover system due to other causes or a release of contaminants into the environment In such a case the inspector should immediately notify the EPA and the DEP and engage a qualified Professional Engineer in order to develop a more detailed and appropriate response

Potential Problem Contingency Response 1 Erosion of surface soil Identify the cause of the erosion if possible and

eliminaterepair it Place new soil in any gullies spread topsoil seed and heavy mulch

2 Sedimentation in drainage channels or pipes Identify the sourcecause of the sedimentation if possible and correct it Remove the sediment to maintain full capacity of the structures

3 Erosion in drainage channels or damage to Identify the cause of the problem if possible and pipes eliminaterepair it Place new rip-rap (and repair

gabions) in any eroded channels install topsoil seed and heavy mulch as necessary Damaged pipes shall be repaired to their original condition

4 Damaged gas vent riser pipe Repair damaged pipe as appropriate Holes smaller than 1-inch diameter can be patched any larger holes or a broken pipe must be cut and fusion-welded by a qualified contractor

5 Differential settlement of cover system Some differential settlement is expected but if drainage is impaired andor water is ponding on the cover surface (or in drainage channels) proper drainage must be restored The initial response shall be to fill depressions with soil or repair drainage channels to drain The cause of the drainage problem shall be assessed in the following Progress Report If repairs to the underlying membrane system are recommended they shall be approved by the EPA before proceeding

96064 01 032699

Potential Problem Contingency Response 6 Soil movement that exposes geomembrane Any significant soil movement or other cause that

(Or other obvious damage to the exposes the geomembrane shall be investigated geomembrane) and assessed in the following Progress Report An

initial response shall be as appropriate to control further damage to the cover system If repairs to the underlying geomembrane system are necessary they shall be approved by the EPA before proceeding

8 EVALUATION OF STABILITY

The stability of the site shall be qualitatively assessed after each inspection Indications of unstable soil and cover system conditions could include longitudinal cracks or depressions in the soil surface or evidence of slumping or impaired drainage at the lower areas of slopes or in drainage channels If either of these conditions are identified additional investigations should be performed to determine if site or slope stability may be impaired At a minimum the identified area of surface depression should be surveyed at the time that settlement monitoring is performed Surveys should then be performed annually to monitor for changes over time The procedures listed in Section 12 of this Plan should be followed for further analysis

The gabion wall at the entrance to Culvert 1 on the eastern side of the landfill should be monitored for tilt as an indication of slope stability The specific location for measuring the tilt is described on the Inspection Record Form attached to this Plan Any changes in tilt of the wall should be identified in the Progress Reports and the implications on stability shall be qualitatively assessed

9 ASSESSMENT OF PASSIVE GAS VENTING SYSTEM

The condition and performance of the passive gas venting system shall be qualitatively assessed after each inspection The condition of the gas vents will be determined by visual observation of the gas vent risers and the adjacent cover surface conditions The vents should be protruding from the cover system with the outlet at least 7 feet above the cover surface (Some leaning of the HDPE pipes is expected) The screens should be in place on the ends of the pipes Where the pipe boots are visible there should be no signs of damage The surrounding soil should be firmly supporting the riser pipe with no voids or spaces that could indicate movement of the riser or adjacent soil If any improper conditions are observed additional investigations should be performed to determine if there is damage to the vent structure that requires repairs

Signs of poor performance would include a clogged gas vent screen or an indication that gas is releasing through or beyond the cover system This condition is usually indicated by stress in the vegetation that can not otherwise be explained If this is the case additional investigations should be performed to determine if gas is not being properly vented and if further repairs or improvements are required

96064 01 0326 99

As an indication of gas vent physical conditions over time the tilt or lean of each gas vent riser should be measured annually during the inspection prior to the NovemberDecember Progress Report As part of the inspection report the data shall be compared to the baseline data from previous inspections A variation of about 2 inches in the angle measurement is expected to occur from variations m temperature and measurement accuracy If any of the gas vents exhibit an unusual change in the tilt angle (more than 3 inches from the previous condition) they should be investigated in more detail during the following inspections

10 EVALUATION OF SANDY BROOK SEDIMENT REMOVAL AREA

The Sandy Brook Sediment Removal Area is located to the north of monitoring well MW-95-4 and is noted as Seep Area on the record drawing Site Plan It is an area that had previously been a depression in the ground next to Sandy Brook The area contained contaminated sediments that have been removed and the area has been filled with soil

The conditions at the Sandy Brook Sediment Removal Area shall be evaluated after each inspection The inspection shall look for evidence of discoloration (ie iron staining) erosion from surface drainage or from high levels of flow in the Brook that could result in a sediment discharge to the Brook Any identified problems shall be repaired to prevent potential impacts to the Brook Repairs shall consist of filling and erosion control construction in accordance with the project specifications

11 IMPACT ON WETLANDS

The impact on the surrounding wetlands shall be evaluated in accordance with the wetlands restoration monitoring plan that has not been developed at the time this PRSC Plan was prepared It is anticipated that the wetlands inspections will be conducted at the same time as the normal site inspections but this will need to be refined and clarified in the wetlands monitoring plan The correction of any identified impact needs to be evaluated and approved by the EPA before any action is implemented

12 SETTLEMENT MONITORING

Settlement of the cover system is expected to occur over time as the waste material continues to decompose This anticipated settlement results in a relatively uniform subsidence of the ground surface is not expected to damage the cover system It is differential settlement that is undesirable because it could damage the cover system and this differential settlement will be identified by problems with surface drainage or by general observations of surface conditions However overall settlement of the landfill will be monitored in order to document the rate and magnitude of settlement The monitoring will occur m the fall of each year and will be reported in the NovemberDecember Progress Report

Settlement monitoring will be conducted by measuring the elevations of monitoring points established on each of four gas vents numbers 7 8 9 and 10 These are the vents located along the highest profile of the landfill and will therefore measure the areas where the greatest settlement is expected The gas vents

9606401 8 OV26 99

only penetrate into the waste about 5 feet so they accurately reflect the elevation and settlement of the landfill surface

If the landfill inspections identify an area with a depression on the surface of the cover system where water does not drain properly or if an area larger than 400 square feet (20 feet by 20 feet or equivalent) has settled by more than 1 foot from the adjacent proper elevations the area needs to be documented and monitored At a minimum the location and elevations of the surface depression should be surveyed at the time that settlement monitoring is performed Surveys should then be performed annually to monitor for changes over time If an area is repaired by filling a depression and it does not continue to settle for the next two years of surveys the annual surveying can be discontinued If a depression is filled and continues to settle after two years the area shall be evaluated to determine if the mobilized tensile stress in the geomembrane exceeds allowable values If it does a geomembrane investigation plan shall be recommended in the monitoring report and the plan shall be approved by the EPA before it is performed

9606401 9 032699

Outline of Sample Progress Report Post-Removal Site Control Plan Saco Municipal Landfill Closure

Saco Maine

1 Summary of PRSC activities that have occurred since last report

2 Summary and evaluation of cover system inspection results bull Identify critical issues or problems bull Characterize performance of vegetative growth and erosion controls Determine if poor

growth or erosion is occurring in particular locations bull Characterize the performance of slope benches and rip-rap downdrains bull Assess the significance of any identified drainage problems soft or wet areas or other

cover system damage bull Assess the performance of the gas venting system bull Characterize the performance of the perimeter drainage zone and outlet pipes

3 Summary and evaluation of conditions outside the limits of the cover system bull Identify critical issues or problems including any indications of leachate seeps bull Characterize the performance of the gabion structure at inlet to Culvert 1 bull Characterize performance of perimeter drainage channels and erosion controls bull Determine if poor growth or erosion is occurring in particular locations bull Assess the condition of the culverts manholes and the rip-rap oulet plunge pools bull Assess the condition and performance of the stormwater detention basin

4 Assess the site and slope stability based on qualitative data

5 Evaluate the conditions at the Sandy Brook Sediment Removal Area Identify problems that should be repaired in order to prevent a sediment discharge to Sandy Brook

6 Identify and evaluate any potential impacts on the surrounding wetlands in accordance with the wetlands monitoring plan once it is developed

7 Summary of the results of settlement monitoring over the post closure period

8 Summarize results of Significant Weather event reports

9 Recommend actions and maintenance activities to occur before the next inspection

Appendices Maintenance Reports Inspection Reports Significant Weather Event Reports

FIGURES

95093 14 DRAF F 012699

MONITORING FORMS

9509314 DRAFT 032filtraquo

Site Plan (attached as a Figure) shall be included with each inspection report in order to show the location of any identified problems or maintenance issues

4 OPERATIONAL SAFETY PLAN

All inspections and maintenance work at this site shall be performed in conformance with the Woodard amp Curran Health and Safety Plan (HASP) or another HASP that is at least as stringent as this one Requirements of the Occupational Safety and Health Act (OSHA) 29 CFR provide the basic safety requirements that shall be followed for all activities on the site

Although the possibility of exposure to hazardous chemicals is not anticipated all individuals at the site should be aware that the cover system is acting as a barrier to potentially hazardous materials buried m the landfill Any actions that could uncover these materials should be avoided If a condition is observed that indicate that potentially hazardous materials may be entering the environment the observation should be reported to the Maine DEP and the EPA

The more likely dangers at the site are accidents related to normal maintenance and inspection activities To prevent workplace accidents safety should be emphasized and practiced during all site activities The key to safety is good common sense Some guidelines for safety practices are the following

STOP AND THINK DOUBLE CHECK AVOID EXTREMES (such as overwork fatigue anger tension and haste)

Maintenance and inspection activities present many opportunities for physical injury to occur This site contains steep slopes and rip-rap drainage structures which could make otherwise normal activities more unpredictable and dangerous The use of equipment at this site should be done with particular care due to the special site conditions Wearing the proper protective clothing and sturdy boots and using common sense can prevent many injuries from occurring Appropriate gloves should be worn when handling materials or working on equipment It is noted that the landfill surface particularly the rip-rap stone channels may harbor bee or wasp nests Persons with an allergy to bee stings should take appropriate precautions

5 EVALUATION OF VEGETATIVE GROWTH EROSION AND OTHER SITE CONDITIONS

The condition of the vegetative growth and signs of erosion shall be evaluated after each inspection It is important for the grass to be kept mowed so that no woody plants become established The grass should be healthy and uniform The inspections should thorough observations of any unusual conditions such as areas where water does not drain wet or soft spots any bulges or depressions in the cover system and any signs of bulk soil movement or significant cracks Similar conditions should be identified in the stormwater management basin and in the areas surrounding the landfill cover system The inspections should also look for signs of improper uses of the site such as off-road vehicle use or other damage

9606401 4 032699

Wherever an area of poor grass growth is at least 100 square feet (10 by 10 or equivalent) the potential causes for this condition should be assessed If it is not due primarily to seasonal weather conditions (ie no ram) then further investigations should be performed to determine if fertilizer or other soil conditioners are necessary The investigations shall be designed to determine if the soil and nutrient conditions meet the requirements of the project specifications If discrete areas of the grass become stressed causes for this problem should be assessed and the problem corrected In general poor grass growth should be corrected by amending the soil as necessary and applying grass seed fertilizer and mulch as specified m the project specifications Section 02485 - Topsoil Seed and Mulch

Any areas of erosion shall be identified by the inspections and shown on the inspection Site Plan Normal maintenance shall be performed and documented in a Maintenance Record Form Any repair work shall be performed according to the requirements in the project specifications A recurring or major problem with erosion shall be addressed as described in the following section of this Plan

6 ASSESSMENT OF EROSION CONTROLS AND STORMWATER MANAGEMENT BASIN

The condition and performance of erosion control systems and the stormwater management basin shall be assessed after each inspection Even if all systems are operating properly normal maintenance will be required as noted in Section 3 of this Plan That section also identifies the depth of sediment that is allowable in the various drainage channels and the procedures for cleaning However if there is evidence of poor performance or damage to systems it is necessary to review the adequacy of the erosion control features Poor performance could include the recurrence of sedimentation m specific places or recurring damage to systems that require repairs In such cases an assessment of the problem shall be performed and a solution identified and implemented

The stormwater management basin is intended to control the rate of runoff from the site by limiting the flow from the basin to a pre-development rate of flow that is much less than the instantaneous runoff rate from the landfill cover area It is anticipated that the lower elevations of the basin along the berm on the east side will have a ground surface condition that is usually wet allowing wetland vegetation to become established This is normal operation and is acceptable The basin should be inspected for any obvious structural or erosion damage and the outlet structure should be inspected for proper operation If damage or clogging is identified the improper conditions shall be corrected in accordance with the record drawings and the project specifications including Section 02715 - Site Piping If sediments reach a depth of 6 inches they shall be removed during dry conditions The removal of sediments shall be performed with tracked equipment that limits the compaction of the soils and quality assurance shall be provided by observation and inspection of the repair activity All maintenance and repair activity shall be recorded on the Maintenance Record Form attached to this Plan

It is noted that groundwater from the closed landfill on the north side of Sandy Brook is proposed to be treated and pumped into Culvert 3 and will then enter the northern end of the stormwater management basin This flow will be a relatively small quantity compared to storm flow quantities so most of this water will enter the wet pool in the stormwater basin and infiltrate into the groundwater

9606401 5 012699

7 POTENTIAL PROBLEMS AND CONTINGENCY PLAN

A number of the potential problems that could occur to the landfill cover system at the site have been identified along with the appropriate contingency response Some items are considered normal maintenance activities as noted previously while some are major repairs that must be performed by a specialty contractor after approval by the EPA Work that can be performed without the specific approval of the EPA includes any maintenance and repair to the cover and slope benches to a depth of one foot below the constructed surface grade or any repairs beyond the limits of the cover system In any case all repairs shall be performed in accordance with the record drawings and project specifications including the quality controlquality assurance procedures These potential problems and responses are summarized in the table on the next page

While unlikely a more severe problem could occur A severe problem could result from an earthquake a failure of the constructed cover system due to other causes or a release of contaminants into the environment In such a case the inspector should immediately notify the EPA and the DEP and engage a qualified Professional Engineer in order to develop a more detailed and appropriate response

Potential Problem Contingency Response 1 Erosion of surface soil Identify the cause of the erosion if possible and

eliminaterepair it Place new soil in any gullies spread topsoil seed and heavy mulch

2 Sedimentation in drainage channels or pipes Identify the sourcecause of the sedimentation if possible and correct it Remove the sediment to maintain full capacity of the structures

3 Erosion in drainage channels or damage to Identify the cause of the problem if possible and pipes eliminaterepair it Place new rip-rap (and repair

gabions) in any eroded channels install topsoil seed and heavy mulch as necessary Damaged pipes shall be repaired to their original condition

4 Damaged gas vent riser pipe Repair damaged pipe as appropriate Holes smaller than 1-inch diameter can be patched any larger holes or a broken pipe must be cut and fusion-welded by a qualified contractor

5 Differential settlement of cover system Some differential settlement is expected but if drainage is impaired andor water is ponding on the cover surface (or in drainage channels) proper drainage must be restored The initial response shall be to fill depressions with soil or repair drainage channels to drain The cause of the drainage problem shall be assessed in the following Progress Report If repairs to the underlying membrane system are recommended they shall be approved by the EPA before proceeding

96064 01 032699

Potential Problem Contingency Response 6 Soil movement that exposes geomembrane Any significant soil movement or other cause that

(Or other obvious damage to the exposes the geomembrane shall be investigated geomembrane) and assessed in the following Progress Report An

initial response shall be as appropriate to control further damage to the cover system If repairs to the underlying geomembrane system are necessary they shall be approved by the EPA before proceeding

8 EVALUATION OF STABILITY

The stability of the site shall be qualitatively assessed after each inspection Indications of unstable soil and cover system conditions could include longitudinal cracks or depressions in the soil surface or evidence of slumping or impaired drainage at the lower areas of slopes or in drainage channels If either of these conditions are identified additional investigations should be performed to determine if site or slope stability may be impaired At a minimum the identified area of surface depression should be surveyed at the time that settlement monitoring is performed Surveys should then be performed annually to monitor for changes over time The procedures listed in Section 12 of this Plan should be followed for further analysis

The gabion wall at the entrance to Culvert 1 on the eastern side of the landfill should be monitored for tilt as an indication of slope stability The specific location for measuring the tilt is described on the Inspection Record Form attached to this Plan Any changes in tilt of the wall should be identified in the Progress Reports and the implications on stability shall be qualitatively assessed

9 ASSESSMENT OF PASSIVE GAS VENTING SYSTEM

The condition and performance of the passive gas venting system shall be qualitatively assessed after each inspection The condition of the gas vents will be determined by visual observation of the gas vent risers and the adjacent cover surface conditions The vents should be protruding from the cover system with the outlet at least 7 feet above the cover surface (Some leaning of the HDPE pipes is expected) The screens should be in place on the ends of the pipes Where the pipe boots are visible there should be no signs of damage The surrounding soil should be firmly supporting the riser pipe with no voids or spaces that could indicate movement of the riser or adjacent soil If any improper conditions are observed additional investigations should be performed to determine if there is damage to the vent structure that requires repairs

Signs of poor performance would include a clogged gas vent screen or an indication that gas is releasing through or beyond the cover system This condition is usually indicated by stress in the vegetation that can not otherwise be explained If this is the case additional investigations should be performed to determine if gas is not being properly vented and if further repairs or improvements are required

96064 01 0326 99

As an indication of gas vent physical conditions over time the tilt or lean of each gas vent riser should be measured annually during the inspection prior to the NovemberDecember Progress Report As part of the inspection report the data shall be compared to the baseline data from previous inspections A variation of about 2 inches in the angle measurement is expected to occur from variations m temperature and measurement accuracy If any of the gas vents exhibit an unusual change in the tilt angle (more than 3 inches from the previous condition) they should be investigated in more detail during the following inspections

10 EVALUATION OF SANDY BROOK SEDIMENT REMOVAL AREA

The Sandy Brook Sediment Removal Area is located to the north of monitoring well MW-95-4 and is noted as Seep Area on the record drawing Site Plan It is an area that had previously been a depression in the ground next to Sandy Brook The area contained contaminated sediments that have been removed and the area has been filled with soil

The conditions at the Sandy Brook Sediment Removal Area shall be evaluated after each inspection The inspection shall look for evidence of discoloration (ie iron staining) erosion from surface drainage or from high levels of flow in the Brook that could result in a sediment discharge to the Brook Any identified problems shall be repaired to prevent potential impacts to the Brook Repairs shall consist of filling and erosion control construction in accordance with the project specifications

11 IMPACT ON WETLANDS

The impact on the surrounding wetlands shall be evaluated in accordance with the wetlands restoration monitoring plan that has not been developed at the time this PRSC Plan was prepared It is anticipated that the wetlands inspections will be conducted at the same time as the normal site inspections but this will need to be refined and clarified in the wetlands monitoring plan The correction of any identified impact needs to be evaluated and approved by the EPA before any action is implemented

12 SETTLEMENT MONITORING

Settlement of the cover system is expected to occur over time as the waste material continues to decompose This anticipated settlement results in a relatively uniform subsidence of the ground surface is not expected to damage the cover system It is differential settlement that is undesirable because it could damage the cover system and this differential settlement will be identified by problems with surface drainage or by general observations of surface conditions However overall settlement of the landfill will be monitored in order to document the rate and magnitude of settlement The monitoring will occur m the fall of each year and will be reported in the NovemberDecember Progress Report

Settlement monitoring will be conducted by measuring the elevations of monitoring points established on each of four gas vents numbers 7 8 9 and 10 These are the vents located along the highest profile of the landfill and will therefore measure the areas where the greatest settlement is expected The gas vents

9606401 8 OV26 99

only penetrate into the waste about 5 feet so they accurately reflect the elevation and settlement of the landfill surface

If the landfill inspections identify an area with a depression on the surface of the cover system where water does not drain properly or if an area larger than 400 square feet (20 feet by 20 feet or equivalent) has settled by more than 1 foot from the adjacent proper elevations the area needs to be documented and monitored At a minimum the location and elevations of the surface depression should be surveyed at the time that settlement monitoring is performed Surveys should then be performed annually to monitor for changes over time If an area is repaired by filling a depression and it does not continue to settle for the next two years of surveys the annual surveying can be discontinued If a depression is filled and continues to settle after two years the area shall be evaluated to determine if the mobilized tensile stress in the geomembrane exceeds allowable values If it does a geomembrane investigation plan shall be recommended in the monitoring report and the plan shall be approved by the EPA before it is performed

9606401 9 032699

Outline of Sample Progress Report Post-Removal Site Control Plan Saco Municipal Landfill Closure

Saco Maine

1 Summary of PRSC activities that have occurred since last report

2 Summary and evaluation of cover system inspection results bull Identify critical issues or problems bull Characterize performance of vegetative growth and erosion controls Determine if poor

growth or erosion is occurring in particular locations bull Characterize the performance of slope benches and rip-rap downdrains bull Assess the significance of any identified drainage problems soft or wet areas or other

cover system damage bull Assess the performance of the gas venting system bull Characterize the performance of the perimeter drainage zone and outlet pipes

3 Summary and evaluation of conditions outside the limits of the cover system bull Identify critical issues or problems including any indications of leachate seeps bull Characterize the performance of the gabion structure at inlet to Culvert 1 bull Characterize performance of perimeter drainage channels and erosion controls bull Determine if poor growth or erosion is occurring in particular locations bull Assess the condition of the culverts manholes and the rip-rap oulet plunge pools bull Assess the condition and performance of the stormwater detention basin

4 Assess the site and slope stability based on qualitative data

5 Evaluate the conditions at the Sandy Brook Sediment Removal Area Identify problems that should be repaired in order to prevent a sediment discharge to Sandy Brook

6 Identify and evaluate any potential impacts on the surrounding wetlands in accordance with the wetlands monitoring plan once it is developed

7 Summary of the results of settlement monitoring over the post closure period

8 Summarize results of Significant Weather event reports

9 Recommend actions and maintenance activities to occur before the next inspection

Appendices Maintenance Reports Inspection Reports Significant Weather Event Reports

FIGURES

95093 14 DRAF F 012699

MONITORING FORMS

9509314 DRAFT 032filtraquo

Wherever an area of poor grass growth is at least 100 square feet (10 by 10 or equivalent) the potential causes for this condition should be assessed If it is not due primarily to seasonal weather conditions (ie no ram) then further investigations should be performed to determine if fertilizer or other soil conditioners are necessary The investigations shall be designed to determine if the soil and nutrient conditions meet the requirements of the project specifications If discrete areas of the grass become stressed causes for this problem should be assessed and the problem corrected In general poor grass growth should be corrected by amending the soil as necessary and applying grass seed fertilizer and mulch as specified m the project specifications Section 02485 - Topsoil Seed and Mulch

Any areas of erosion shall be identified by the inspections and shown on the inspection Site Plan Normal maintenance shall be performed and documented in a Maintenance Record Form Any repair work shall be performed according to the requirements in the project specifications A recurring or major problem with erosion shall be addressed as described in the following section of this Plan

6 ASSESSMENT OF EROSION CONTROLS AND STORMWATER MANAGEMENT BASIN

The condition and performance of erosion control systems and the stormwater management basin shall be assessed after each inspection Even if all systems are operating properly normal maintenance will be required as noted in Section 3 of this Plan That section also identifies the depth of sediment that is allowable in the various drainage channels and the procedures for cleaning However if there is evidence of poor performance or damage to systems it is necessary to review the adequacy of the erosion control features Poor performance could include the recurrence of sedimentation m specific places or recurring damage to systems that require repairs In such cases an assessment of the problem shall be performed and a solution identified and implemented

The stormwater management basin is intended to control the rate of runoff from the site by limiting the flow from the basin to a pre-development rate of flow that is much less than the instantaneous runoff rate from the landfill cover area It is anticipated that the lower elevations of the basin along the berm on the east side will have a ground surface condition that is usually wet allowing wetland vegetation to become established This is normal operation and is acceptable The basin should be inspected for any obvious structural or erosion damage and the outlet structure should be inspected for proper operation If damage or clogging is identified the improper conditions shall be corrected in accordance with the record drawings and the project specifications including Section 02715 - Site Piping If sediments reach a depth of 6 inches they shall be removed during dry conditions The removal of sediments shall be performed with tracked equipment that limits the compaction of the soils and quality assurance shall be provided by observation and inspection of the repair activity All maintenance and repair activity shall be recorded on the Maintenance Record Form attached to this Plan

It is noted that groundwater from the closed landfill on the north side of Sandy Brook is proposed to be treated and pumped into Culvert 3 and will then enter the northern end of the stormwater management basin This flow will be a relatively small quantity compared to storm flow quantities so most of this water will enter the wet pool in the stormwater basin and infiltrate into the groundwater

9606401 5 012699

7 POTENTIAL PROBLEMS AND CONTINGENCY PLAN

A number of the potential problems that could occur to the landfill cover system at the site have been identified along with the appropriate contingency response Some items are considered normal maintenance activities as noted previously while some are major repairs that must be performed by a specialty contractor after approval by the EPA Work that can be performed without the specific approval of the EPA includes any maintenance and repair to the cover and slope benches to a depth of one foot below the constructed surface grade or any repairs beyond the limits of the cover system In any case all repairs shall be performed in accordance with the record drawings and project specifications including the quality controlquality assurance procedures These potential problems and responses are summarized in the table on the next page

While unlikely a more severe problem could occur A severe problem could result from an earthquake a failure of the constructed cover system due to other causes or a release of contaminants into the environment In such a case the inspector should immediately notify the EPA and the DEP and engage a qualified Professional Engineer in order to develop a more detailed and appropriate response

Potential Problem Contingency Response 1 Erosion of surface soil Identify the cause of the erosion if possible and

eliminaterepair it Place new soil in any gullies spread topsoil seed and heavy mulch

2 Sedimentation in drainage channels or pipes Identify the sourcecause of the sedimentation if possible and correct it Remove the sediment to maintain full capacity of the structures

3 Erosion in drainage channels or damage to Identify the cause of the problem if possible and pipes eliminaterepair it Place new rip-rap (and repair

gabions) in any eroded channels install topsoil seed and heavy mulch as necessary Damaged pipes shall be repaired to their original condition

4 Damaged gas vent riser pipe Repair damaged pipe as appropriate Holes smaller than 1-inch diameter can be patched any larger holes or a broken pipe must be cut and fusion-welded by a qualified contractor

5 Differential settlement of cover system Some differential settlement is expected but if drainage is impaired andor water is ponding on the cover surface (or in drainage channels) proper drainage must be restored The initial response shall be to fill depressions with soil or repair drainage channels to drain The cause of the drainage problem shall be assessed in the following Progress Report If repairs to the underlying membrane system are recommended they shall be approved by the EPA before proceeding

96064 01 032699

Potential Problem Contingency Response 6 Soil movement that exposes geomembrane Any significant soil movement or other cause that

(Or other obvious damage to the exposes the geomembrane shall be investigated geomembrane) and assessed in the following Progress Report An

initial response shall be as appropriate to control further damage to the cover system If repairs to the underlying geomembrane system are necessary they shall be approved by the EPA before proceeding

8 EVALUATION OF STABILITY

The stability of the site shall be qualitatively assessed after each inspection Indications of unstable soil and cover system conditions could include longitudinal cracks or depressions in the soil surface or evidence of slumping or impaired drainage at the lower areas of slopes or in drainage channels If either of these conditions are identified additional investigations should be performed to determine if site or slope stability may be impaired At a minimum the identified area of surface depression should be surveyed at the time that settlement monitoring is performed Surveys should then be performed annually to monitor for changes over time The procedures listed in Section 12 of this Plan should be followed for further analysis

The gabion wall at the entrance to Culvert 1 on the eastern side of the landfill should be monitored for tilt as an indication of slope stability The specific location for measuring the tilt is described on the Inspection Record Form attached to this Plan Any changes in tilt of the wall should be identified in the Progress Reports and the implications on stability shall be qualitatively assessed

9 ASSESSMENT OF PASSIVE GAS VENTING SYSTEM

The condition and performance of the passive gas venting system shall be qualitatively assessed after each inspection The condition of the gas vents will be determined by visual observation of the gas vent risers and the adjacent cover surface conditions The vents should be protruding from the cover system with the outlet at least 7 feet above the cover surface (Some leaning of the HDPE pipes is expected) The screens should be in place on the ends of the pipes Where the pipe boots are visible there should be no signs of damage The surrounding soil should be firmly supporting the riser pipe with no voids or spaces that could indicate movement of the riser or adjacent soil If any improper conditions are observed additional investigations should be performed to determine if there is damage to the vent structure that requires repairs

Signs of poor performance would include a clogged gas vent screen or an indication that gas is releasing through or beyond the cover system This condition is usually indicated by stress in the vegetation that can not otherwise be explained If this is the case additional investigations should be performed to determine if gas is not being properly vented and if further repairs or improvements are required

96064 01 0326 99

As an indication of gas vent physical conditions over time the tilt or lean of each gas vent riser should be measured annually during the inspection prior to the NovemberDecember Progress Report As part of the inspection report the data shall be compared to the baseline data from previous inspections A variation of about 2 inches in the angle measurement is expected to occur from variations m temperature and measurement accuracy If any of the gas vents exhibit an unusual change in the tilt angle (more than 3 inches from the previous condition) they should be investigated in more detail during the following inspections

10 EVALUATION OF SANDY BROOK SEDIMENT REMOVAL AREA

The Sandy Brook Sediment Removal Area is located to the north of monitoring well MW-95-4 and is noted as Seep Area on the record drawing Site Plan It is an area that had previously been a depression in the ground next to Sandy Brook The area contained contaminated sediments that have been removed and the area has been filled with soil

The conditions at the Sandy Brook Sediment Removal Area shall be evaluated after each inspection The inspection shall look for evidence of discoloration (ie iron staining) erosion from surface drainage or from high levels of flow in the Brook that could result in a sediment discharge to the Brook Any identified problems shall be repaired to prevent potential impacts to the Brook Repairs shall consist of filling and erosion control construction in accordance with the project specifications

11 IMPACT ON WETLANDS

The impact on the surrounding wetlands shall be evaluated in accordance with the wetlands restoration monitoring plan that has not been developed at the time this PRSC Plan was prepared It is anticipated that the wetlands inspections will be conducted at the same time as the normal site inspections but this will need to be refined and clarified in the wetlands monitoring plan The correction of any identified impact needs to be evaluated and approved by the EPA before any action is implemented

12 SETTLEMENT MONITORING

Settlement of the cover system is expected to occur over time as the waste material continues to decompose This anticipated settlement results in a relatively uniform subsidence of the ground surface is not expected to damage the cover system It is differential settlement that is undesirable because it could damage the cover system and this differential settlement will be identified by problems with surface drainage or by general observations of surface conditions However overall settlement of the landfill will be monitored in order to document the rate and magnitude of settlement The monitoring will occur m the fall of each year and will be reported in the NovemberDecember Progress Report

Settlement monitoring will be conducted by measuring the elevations of monitoring points established on each of four gas vents numbers 7 8 9 and 10 These are the vents located along the highest profile of the landfill and will therefore measure the areas where the greatest settlement is expected The gas vents

9606401 8 OV26 99

only penetrate into the waste about 5 feet so they accurately reflect the elevation and settlement of the landfill surface

If the landfill inspections identify an area with a depression on the surface of the cover system where water does not drain properly or if an area larger than 400 square feet (20 feet by 20 feet or equivalent) has settled by more than 1 foot from the adjacent proper elevations the area needs to be documented and monitored At a minimum the location and elevations of the surface depression should be surveyed at the time that settlement monitoring is performed Surveys should then be performed annually to monitor for changes over time If an area is repaired by filling a depression and it does not continue to settle for the next two years of surveys the annual surveying can be discontinued If a depression is filled and continues to settle after two years the area shall be evaluated to determine if the mobilized tensile stress in the geomembrane exceeds allowable values If it does a geomembrane investigation plan shall be recommended in the monitoring report and the plan shall be approved by the EPA before it is performed

9606401 9 032699

Outline of Sample Progress Report Post-Removal Site Control Plan Saco Municipal Landfill Closure

Saco Maine

1 Summary of PRSC activities that have occurred since last report

2 Summary and evaluation of cover system inspection results bull Identify critical issues or problems bull Characterize performance of vegetative growth and erosion controls Determine if poor

growth or erosion is occurring in particular locations bull Characterize the performance of slope benches and rip-rap downdrains bull Assess the significance of any identified drainage problems soft or wet areas or other

cover system damage bull Assess the performance of the gas venting system bull Characterize the performance of the perimeter drainage zone and outlet pipes

3 Summary and evaluation of conditions outside the limits of the cover system bull Identify critical issues or problems including any indications of leachate seeps bull Characterize the performance of the gabion structure at inlet to Culvert 1 bull Characterize performance of perimeter drainage channels and erosion controls bull Determine if poor growth or erosion is occurring in particular locations bull Assess the condition of the culverts manholes and the rip-rap oulet plunge pools bull Assess the condition and performance of the stormwater detention basin

4 Assess the site and slope stability based on qualitative data

5 Evaluate the conditions at the Sandy Brook Sediment Removal Area Identify problems that should be repaired in order to prevent a sediment discharge to Sandy Brook

6 Identify and evaluate any potential impacts on the surrounding wetlands in accordance with the wetlands monitoring plan once it is developed

7 Summary of the results of settlement monitoring over the post closure period

8 Summarize results of Significant Weather event reports

9 Recommend actions and maintenance activities to occur before the next inspection

Appendices Maintenance Reports Inspection Reports Significant Weather Event Reports

FIGURES

95093 14 DRAF F 012699

MONITORING FORMS

9509314 DRAFT 032filtraquo

7 POTENTIAL PROBLEMS AND CONTINGENCY PLAN

A number of the potential problems that could occur to the landfill cover system at the site have been identified along with the appropriate contingency response Some items are considered normal maintenance activities as noted previously while some are major repairs that must be performed by a specialty contractor after approval by the EPA Work that can be performed without the specific approval of the EPA includes any maintenance and repair to the cover and slope benches to a depth of one foot below the constructed surface grade or any repairs beyond the limits of the cover system In any case all repairs shall be performed in accordance with the record drawings and project specifications including the quality controlquality assurance procedures These potential problems and responses are summarized in the table on the next page

While unlikely a more severe problem could occur A severe problem could result from an earthquake a failure of the constructed cover system due to other causes or a release of contaminants into the environment In such a case the inspector should immediately notify the EPA and the DEP and engage a qualified Professional Engineer in order to develop a more detailed and appropriate response

Potential Problem Contingency Response 1 Erosion of surface soil Identify the cause of the erosion if possible and

eliminaterepair it Place new soil in any gullies spread topsoil seed and heavy mulch

2 Sedimentation in drainage channels or pipes Identify the sourcecause of the sedimentation if possible and correct it Remove the sediment to maintain full capacity of the structures

3 Erosion in drainage channels or damage to Identify the cause of the problem if possible and pipes eliminaterepair it Place new rip-rap (and repair

gabions) in any eroded channels install topsoil seed and heavy mulch as necessary Damaged pipes shall be repaired to their original condition

4 Damaged gas vent riser pipe Repair damaged pipe as appropriate Holes smaller than 1-inch diameter can be patched any larger holes or a broken pipe must be cut and fusion-welded by a qualified contractor

5 Differential settlement of cover system Some differential settlement is expected but if drainage is impaired andor water is ponding on the cover surface (or in drainage channels) proper drainage must be restored The initial response shall be to fill depressions with soil or repair drainage channels to drain The cause of the drainage problem shall be assessed in the following Progress Report If repairs to the underlying membrane system are recommended they shall be approved by the EPA before proceeding

96064 01 032699

Potential Problem Contingency Response 6 Soil movement that exposes geomembrane Any significant soil movement or other cause that

(Or other obvious damage to the exposes the geomembrane shall be investigated geomembrane) and assessed in the following Progress Report An

initial response shall be as appropriate to control further damage to the cover system If repairs to the underlying geomembrane system are necessary they shall be approved by the EPA before proceeding

8 EVALUATION OF STABILITY

The stability of the site shall be qualitatively assessed after each inspection Indications of unstable soil and cover system conditions could include longitudinal cracks or depressions in the soil surface or evidence of slumping or impaired drainage at the lower areas of slopes or in drainage channels If either of these conditions are identified additional investigations should be performed to determine if site or slope stability may be impaired At a minimum the identified area of surface depression should be surveyed at the time that settlement monitoring is performed Surveys should then be performed annually to monitor for changes over time The procedures listed in Section 12 of this Plan should be followed for further analysis

The gabion wall at the entrance to Culvert 1 on the eastern side of the landfill should be monitored for tilt as an indication of slope stability The specific location for measuring the tilt is described on the Inspection Record Form attached to this Plan Any changes in tilt of the wall should be identified in the Progress Reports and the implications on stability shall be qualitatively assessed

9 ASSESSMENT OF PASSIVE GAS VENTING SYSTEM

The condition and performance of the passive gas venting system shall be qualitatively assessed after each inspection The condition of the gas vents will be determined by visual observation of the gas vent risers and the adjacent cover surface conditions The vents should be protruding from the cover system with the outlet at least 7 feet above the cover surface (Some leaning of the HDPE pipes is expected) The screens should be in place on the ends of the pipes Where the pipe boots are visible there should be no signs of damage The surrounding soil should be firmly supporting the riser pipe with no voids or spaces that could indicate movement of the riser or adjacent soil If any improper conditions are observed additional investigations should be performed to determine if there is damage to the vent structure that requires repairs

Signs of poor performance would include a clogged gas vent screen or an indication that gas is releasing through or beyond the cover system This condition is usually indicated by stress in the vegetation that can not otherwise be explained If this is the case additional investigations should be performed to determine if gas is not being properly vented and if further repairs or improvements are required

96064 01 0326 99

As an indication of gas vent physical conditions over time the tilt or lean of each gas vent riser should be measured annually during the inspection prior to the NovemberDecember Progress Report As part of the inspection report the data shall be compared to the baseline data from previous inspections A variation of about 2 inches in the angle measurement is expected to occur from variations m temperature and measurement accuracy If any of the gas vents exhibit an unusual change in the tilt angle (more than 3 inches from the previous condition) they should be investigated in more detail during the following inspections

10 EVALUATION OF SANDY BROOK SEDIMENT REMOVAL AREA

The Sandy Brook Sediment Removal Area is located to the north of monitoring well MW-95-4 and is noted as Seep Area on the record drawing Site Plan It is an area that had previously been a depression in the ground next to Sandy Brook The area contained contaminated sediments that have been removed and the area has been filled with soil

The conditions at the Sandy Brook Sediment Removal Area shall be evaluated after each inspection The inspection shall look for evidence of discoloration (ie iron staining) erosion from surface drainage or from high levels of flow in the Brook that could result in a sediment discharge to the Brook Any identified problems shall be repaired to prevent potential impacts to the Brook Repairs shall consist of filling and erosion control construction in accordance with the project specifications

11 IMPACT ON WETLANDS

The impact on the surrounding wetlands shall be evaluated in accordance with the wetlands restoration monitoring plan that has not been developed at the time this PRSC Plan was prepared It is anticipated that the wetlands inspections will be conducted at the same time as the normal site inspections but this will need to be refined and clarified in the wetlands monitoring plan The correction of any identified impact needs to be evaluated and approved by the EPA before any action is implemented

12 SETTLEMENT MONITORING

Settlement of the cover system is expected to occur over time as the waste material continues to decompose This anticipated settlement results in a relatively uniform subsidence of the ground surface is not expected to damage the cover system It is differential settlement that is undesirable because it could damage the cover system and this differential settlement will be identified by problems with surface drainage or by general observations of surface conditions However overall settlement of the landfill will be monitored in order to document the rate and magnitude of settlement The monitoring will occur m the fall of each year and will be reported in the NovemberDecember Progress Report

Settlement monitoring will be conducted by measuring the elevations of monitoring points established on each of four gas vents numbers 7 8 9 and 10 These are the vents located along the highest profile of the landfill and will therefore measure the areas where the greatest settlement is expected The gas vents

9606401 8 OV26 99

only penetrate into the waste about 5 feet so they accurately reflect the elevation and settlement of the landfill surface

If the landfill inspections identify an area with a depression on the surface of the cover system where water does not drain properly or if an area larger than 400 square feet (20 feet by 20 feet or equivalent) has settled by more than 1 foot from the adjacent proper elevations the area needs to be documented and monitored At a minimum the location and elevations of the surface depression should be surveyed at the time that settlement monitoring is performed Surveys should then be performed annually to monitor for changes over time If an area is repaired by filling a depression and it does not continue to settle for the next two years of surveys the annual surveying can be discontinued If a depression is filled and continues to settle after two years the area shall be evaluated to determine if the mobilized tensile stress in the geomembrane exceeds allowable values If it does a geomembrane investigation plan shall be recommended in the monitoring report and the plan shall be approved by the EPA before it is performed

9606401 9 032699

Outline of Sample Progress Report Post-Removal Site Control Plan Saco Municipal Landfill Closure

Saco Maine

1 Summary of PRSC activities that have occurred since last report

2 Summary and evaluation of cover system inspection results bull Identify critical issues or problems bull Characterize performance of vegetative growth and erosion controls Determine if poor

growth or erosion is occurring in particular locations bull Characterize the performance of slope benches and rip-rap downdrains bull Assess the significance of any identified drainage problems soft or wet areas or other

cover system damage bull Assess the performance of the gas venting system bull Characterize the performance of the perimeter drainage zone and outlet pipes

3 Summary and evaluation of conditions outside the limits of the cover system bull Identify critical issues or problems including any indications of leachate seeps bull Characterize the performance of the gabion structure at inlet to Culvert 1 bull Characterize performance of perimeter drainage channels and erosion controls bull Determine if poor growth or erosion is occurring in particular locations bull Assess the condition of the culverts manholes and the rip-rap oulet plunge pools bull Assess the condition and performance of the stormwater detention basin

4 Assess the site and slope stability based on qualitative data

5 Evaluate the conditions at the Sandy Brook Sediment Removal Area Identify problems that should be repaired in order to prevent a sediment discharge to Sandy Brook

6 Identify and evaluate any potential impacts on the surrounding wetlands in accordance with the wetlands monitoring plan once it is developed

7 Summary of the results of settlement monitoring over the post closure period

8 Summarize results of Significant Weather event reports

9 Recommend actions and maintenance activities to occur before the next inspection

Appendices Maintenance Reports Inspection Reports Significant Weather Event Reports

FIGURES

95093 14 DRAF F 012699

MONITORING FORMS

9509314 DRAFT 032filtraquo

Potential Problem Contingency Response 6 Soil movement that exposes geomembrane Any significant soil movement or other cause that

(Or other obvious damage to the exposes the geomembrane shall be investigated geomembrane) and assessed in the following Progress Report An

initial response shall be as appropriate to control further damage to the cover system If repairs to the underlying geomembrane system are necessary they shall be approved by the EPA before proceeding

8 EVALUATION OF STABILITY

The stability of the site shall be qualitatively assessed after each inspection Indications of unstable soil and cover system conditions could include longitudinal cracks or depressions in the soil surface or evidence of slumping or impaired drainage at the lower areas of slopes or in drainage channels If either of these conditions are identified additional investigations should be performed to determine if site or slope stability may be impaired At a minimum the identified area of surface depression should be surveyed at the time that settlement monitoring is performed Surveys should then be performed annually to monitor for changes over time The procedures listed in Section 12 of this Plan should be followed for further analysis

The gabion wall at the entrance to Culvert 1 on the eastern side of the landfill should be monitored for tilt as an indication of slope stability The specific location for measuring the tilt is described on the Inspection Record Form attached to this Plan Any changes in tilt of the wall should be identified in the Progress Reports and the implications on stability shall be qualitatively assessed

9 ASSESSMENT OF PASSIVE GAS VENTING SYSTEM

The condition and performance of the passive gas venting system shall be qualitatively assessed after each inspection The condition of the gas vents will be determined by visual observation of the gas vent risers and the adjacent cover surface conditions The vents should be protruding from the cover system with the outlet at least 7 feet above the cover surface (Some leaning of the HDPE pipes is expected) The screens should be in place on the ends of the pipes Where the pipe boots are visible there should be no signs of damage The surrounding soil should be firmly supporting the riser pipe with no voids or spaces that could indicate movement of the riser or adjacent soil If any improper conditions are observed additional investigations should be performed to determine if there is damage to the vent structure that requires repairs

Signs of poor performance would include a clogged gas vent screen or an indication that gas is releasing through or beyond the cover system This condition is usually indicated by stress in the vegetation that can not otherwise be explained If this is the case additional investigations should be performed to determine if gas is not being properly vented and if further repairs or improvements are required

96064 01 0326 99

As an indication of gas vent physical conditions over time the tilt or lean of each gas vent riser should be measured annually during the inspection prior to the NovemberDecember Progress Report As part of the inspection report the data shall be compared to the baseline data from previous inspections A variation of about 2 inches in the angle measurement is expected to occur from variations m temperature and measurement accuracy If any of the gas vents exhibit an unusual change in the tilt angle (more than 3 inches from the previous condition) they should be investigated in more detail during the following inspections

10 EVALUATION OF SANDY BROOK SEDIMENT REMOVAL AREA

The Sandy Brook Sediment Removal Area is located to the north of monitoring well MW-95-4 and is noted as Seep Area on the record drawing Site Plan It is an area that had previously been a depression in the ground next to Sandy Brook The area contained contaminated sediments that have been removed and the area has been filled with soil

The conditions at the Sandy Brook Sediment Removal Area shall be evaluated after each inspection The inspection shall look for evidence of discoloration (ie iron staining) erosion from surface drainage or from high levels of flow in the Brook that could result in a sediment discharge to the Brook Any identified problems shall be repaired to prevent potential impacts to the Brook Repairs shall consist of filling and erosion control construction in accordance with the project specifications

11 IMPACT ON WETLANDS

The impact on the surrounding wetlands shall be evaluated in accordance with the wetlands restoration monitoring plan that has not been developed at the time this PRSC Plan was prepared It is anticipated that the wetlands inspections will be conducted at the same time as the normal site inspections but this will need to be refined and clarified in the wetlands monitoring plan The correction of any identified impact needs to be evaluated and approved by the EPA before any action is implemented

12 SETTLEMENT MONITORING

Settlement of the cover system is expected to occur over time as the waste material continues to decompose This anticipated settlement results in a relatively uniform subsidence of the ground surface is not expected to damage the cover system It is differential settlement that is undesirable because it could damage the cover system and this differential settlement will be identified by problems with surface drainage or by general observations of surface conditions However overall settlement of the landfill will be monitored in order to document the rate and magnitude of settlement The monitoring will occur m the fall of each year and will be reported in the NovemberDecember Progress Report

Settlement monitoring will be conducted by measuring the elevations of monitoring points established on each of four gas vents numbers 7 8 9 and 10 These are the vents located along the highest profile of the landfill and will therefore measure the areas where the greatest settlement is expected The gas vents

9606401 8 OV26 99

only penetrate into the waste about 5 feet so they accurately reflect the elevation and settlement of the landfill surface

If the landfill inspections identify an area with a depression on the surface of the cover system where water does not drain properly or if an area larger than 400 square feet (20 feet by 20 feet or equivalent) has settled by more than 1 foot from the adjacent proper elevations the area needs to be documented and monitored At a minimum the location and elevations of the surface depression should be surveyed at the time that settlement monitoring is performed Surveys should then be performed annually to monitor for changes over time If an area is repaired by filling a depression and it does not continue to settle for the next two years of surveys the annual surveying can be discontinued If a depression is filled and continues to settle after two years the area shall be evaluated to determine if the mobilized tensile stress in the geomembrane exceeds allowable values If it does a geomembrane investigation plan shall be recommended in the monitoring report and the plan shall be approved by the EPA before it is performed

9606401 9 032699

Outline of Sample Progress Report Post-Removal Site Control Plan Saco Municipal Landfill Closure

Saco Maine

1 Summary of PRSC activities that have occurred since last report

2 Summary and evaluation of cover system inspection results bull Identify critical issues or problems bull Characterize performance of vegetative growth and erosion controls Determine if poor

growth or erosion is occurring in particular locations bull Characterize the performance of slope benches and rip-rap downdrains bull Assess the significance of any identified drainage problems soft or wet areas or other

cover system damage bull Assess the performance of the gas venting system bull Characterize the performance of the perimeter drainage zone and outlet pipes

3 Summary and evaluation of conditions outside the limits of the cover system bull Identify critical issues or problems including any indications of leachate seeps bull Characterize the performance of the gabion structure at inlet to Culvert 1 bull Characterize performance of perimeter drainage channels and erosion controls bull Determine if poor growth or erosion is occurring in particular locations bull Assess the condition of the culverts manholes and the rip-rap oulet plunge pools bull Assess the condition and performance of the stormwater detention basin

4 Assess the site and slope stability based on qualitative data

5 Evaluate the conditions at the Sandy Brook Sediment Removal Area Identify problems that should be repaired in order to prevent a sediment discharge to Sandy Brook

6 Identify and evaluate any potential impacts on the surrounding wetlands in accordance with the wetlands monitoring plan once it is developed

7 Summary of the results of settlement monitoring over the post closure period

8 Summarize results of Significant Weather event reports

9 Recommend actions and maintenance activities to occur before the next inspection

Appendices Maintenance Reports Inspection Reports Significant Weather Event Reports

FIGURES

95093 14 DRAF F 012699

MONITORING FORMS

9509314 DRAFT 032filtraquo

As an indication of gas vent physical conditions over time the tilt or lean of each gas vent riser should be measured annually during the inspection prior to the NovemberDecember Progress Report As part of the inspection report the data shall be compared to the baseline data from previous inspections A variation of about 2 inches in the angle measurement is expected to occur from variations m temperature and measurement accuracy If any of the gas vents exhibit an unusual change in the tilt angle (more than 3 inches from the previous condition) they should be investigated in more detail during the following inspections

10 EVALUATION OF SANDY BROOK SEDIMENT REMOVAL AREA

The Sandy Brook Sediment Removal Area is located to the north of monitoring well MW-95-4 and is noted as Seep Area on the record drawing Site Plan It is an area that had previously been a depression in the ground next to Sandy Brook The area contained contaminated sediments that have been removed and the area has been filled with soil

The conditions at the Sandy Brook Sediment Removal Area shall be evaluated after each inspection The inspection shall look for evidence of discoloration (ie iron staining) erosion from surface drainage or from high levels of flow in the Brook that could result in a sediment discharge to the Brook Any identified problems shall be repaired to prevent potential impacts to the Brook Repairs shall consist of filling and erosion control construction in accordance with the project specifications

11 IMPACT ON WETLANDS

The impact on the surrounding wetlands shall be evaluated in accordance with the wetlands restoration monitoring plan that has not been developed at the time this PRSC Plan was prepared It is anticipated that the wetlands inspections will be conducted at the same time as the normal site inspections but this will need to be refined and clarified in the wetlands monitoring plan The correction of any identified impact needs to be evaluated and approved by the EPA before any action is implemented

12 SETTLEMENT MONITORING

Settlement of the cover system is expected to occur over time as the waste material continues to decompose This anticipated settlement results in a relatively uniform subsidence of the ground surface is not expected to damage the cover system It is differential settlement that is undesirable because it could damage the cover system and this differential settlement will be identified by problems with surface drainage or by general observations of surface conditions However overall settlement of the landfill will be monitored in order to document the rate and magnitude of settlement The monitoring will occur m the fall of each year and will be reported in the NovemberDecember Progress Report

Settlement monitoring will be conducted by measuring the elevations of monitoring points established on each of four gas vents numbers 7 8 9 and 10 These are the vents located along the highest profile of the landfill and will therefore measure the areas where the greatest settlement is expected The gas vents

9606401 8 OV26 99

only penetrate into the waste about 5 feet so they accurately reflect the elevation and settlement of the landfill surface

If the landfill inspections identify an area with a depression on the surface of the cover system where water does not drain properly or if an area larger than 400 square feet (20 feet by 20 feet or equivalent) has settled by more than 1 foot from the adjacent proper elevations the area needs to be documented and monitored At a minimum the location and elevations of the surface depression should be surveyed at the time that settlement monitoring is performed Surveys should then be performed annually to monitor for changes over time If an area is repaired by filling a depression and it does not continue to settle for the next two years of surveys the annual surveying can be discontinued If a depression is filled and continues to settle after two years the area shall be evaluated to determine if the mobilized tensile stress in the geomembrane exceeds allowable values If it does a geomembrane investigation plan shall be recommended in the monitoring report and the plan shall be approved by the EPA before it is performed

9606401 9 032699

Outline of Sample Progress Report Post-Removal Site Control Plan Saco Municipal Landfill Closure

Saco Maine

1 Summary of PRSC activities that have occurred since last report

2 Summary and evaluation of cover system inspection results bull Identify critical issues or problems bull Characterize performance of vegetative growth and erosion controls Determine if poor

growth or erosion is occurring in particular locations bull Characterize the performance of slope benches and rip-rap downdrains bull Assess the significance of any identified drainage problems soft or wet areas or other

cover system damage bull Assess the performance of the gas venting system bull Characterize the performance of the perimeter drainage zone and outlet pipes

3 Summary and evaluation of conditions outside the limits of the cover system bull Identify critical issues or problems including any indications of leachate seeps bull Characterize the performance of the gabion structure at inlet to Culvert 1 bull Characterize performance of perimeter drainage channels and erosion controls bull Determine if poor growth or erosion is occurring in particular locations bull Assess the condition of the culverts manholes and the rip-rap oulet plunge pools bull Assess the condition and performance of the stormwater detention basin

4 Assess the site and slope stability based on qualitative data

5 Evaluate the conditions at the Sandy Brook Sediment Removal Area Identify problems that should be repaired in order to prevent a sediment discharge to Sandy Brook

6 Identify and evaluate any potential impacts on the surrounding wetlands in accordance with the wetlands monitoring plan once it is developed

7 Summary of the results of settlement monitoring over the post closure period

8 Summarize results of Significant Weather event reports

9 Recommend actions and maintenance activities to occur before the next inspection

Appendices Maintenance Reports Inspection Reports Significant Weather Event Reports

FIGURES

95093 14 DRAF F 012699

MONITORING FORMS

9509314 DRAFT 032filtraquo

only penetrate into the waste about 5 feet so they accurately reflect the elevation and settlement of the landfill surface

If the landfill inspections identify an area with a depression on the surface of the cover system where water does not drain properly or if an area larger than 400 square feet (20 feet by 20 feet or equivalent) has settled by more than 1 foot from the adjacent proper elevations the area needs to be documented and monitored At a minimum the location and elevations of the surface depression should be surveyed at the time that settlement monitoring is performed Surveys should then be performed annually to monitor for changes over time If an area is repaired by filling a depression and it does not continue to settle for the next two years of surveys the annual surveying can be discontinued If a depression is filled and continues to settle after two years the area shall be evaluated to determine if the mobilized tensile stress in the geomembrane exceeds allowable values If it does a geomembrane investigation plan shall be recommended in the monitoring report and the plan shall be approved by the EPA before it is performed

9606401 9 032699

Outline of Sample Progress Report Post-Removal Site Control Plan Saco Municipal Landfill Closure

Saco Maine

1 Summary of PRSC activities that have occurred since last report

2 Summary and evaluation of cover system inspection results bull Identify critical issues or problems bull Characterize performance of vegetative growth and erosion controls Determine if poor

growth or erosion is occurring in particular locations bull Characterize the performance of slope benches and rip-rap downdrains bull Assess the significance of any identified drainage problems soft or wet areas or other

cover system damage bull Assess the performance of the gas venting system bull Characterize the performance of the perimeter drainage zone and outlet pipes

3 Summary and evaluation of conditions outside the limits of the cover system bull Identify critical issues or problems including any indications of leachate seeps bull Characterize the performance of the gabion structure at inlet to Culvert 1 bull Characterize performance of perimeter drainage channels and erosion controls bull Determine if poor growth or erosion is occurring in particular locations bull Assess the condition of the culverts manholes and the rip-rap oulet plunge pools bull Assess the condition and performance of the stormwater detention basin

4 Assess the site and slope stability based on qualitative data

5 Evaluate the conditions at the Sandy Brook Sediment Removal Area Identify problems that should be repaired in order to prevent a sediment discharge to Sandy Brook

6 Identify and evaluate any potential impacts on the surrounding wetlands in accordance with the wetlands monitoring plan once it is developed

7 Summary of the results of settlement monitoring over the post closure period

8 Summarize results of Significant Weather event reports

9 Recommend actions and maintenance activities to occur before the next inspection

Appendices Maintenance Reports Inspection Reports Significant Weather Event Reports

FIGURES

95093 14 DRAF F 012699

MONITORING FORMS

9509314 DRAFT 032filtraquo

Outline of Sample Progress Report Post-Removal Site Control Plan Saco Municipal Landfill Closure

Saco Maine

1 Summary of PRSC activities that have occurred since last report

2 Summary and evaluation of cover system inspection results bull Identify critical issues or problems bull Characterize performance of vegetative growth and erosion controls Determine if poor

growth or erosion is occurring in particular locations bull Characterize the performance of slope benches and rip-rap downdrains bull Assess the significance of any identified drainage problems soft or wet areas or other

cover system damage bull Assess the performance of the gas venting system bull Characterize the performance of the perimeter drainage zone and outlet pipes

3 Summary and evaluation of conditions outside the limits of the cover system bull Identify critical issues or problems including any indications of leachate seeps bull Characterize the performance of the gabion structure at inlet to Culvert 1 bull Characterize performance of perimeter drainage channels and erosion controls bull Determine if poor growth or erosion is occurring in particular locations bull Assess the condition of the culverts manholes and the rip-rap oulet plunge pools bull Assess the condition and performance of the stormwater detention basin

4 Assess the site and slope stability based on qualitative data

5 Evaluate the conditions at the Sandy Brook Sediment Removal Area Identify problems that should be repaired in order to prevent a sediment discharge to Sandy Brook

6 Identify and evaluate any potential impacts on the surrounding wetlands in accordance with the wetlands monitoring plan once it is developed

7 Summary of the results of settlement monitoring over the post closure period

8 Summarize results of Significant Weather event reports

9 Recommend actions and maintenance activities to occur before the next inspection

Appendices Maintenance Reports Inspection Reports Significant Weather Event Reports

FIGURES

95093 14 DRAF F 012699

MONITORING FORMS

9509314 DRAFT 032filtraquo

FIGURES

95093 14 DRAF F 012699

MONITORING FORMS

9509314 DRAFT 032filtraquo

MONITORING FORMS

9509314 DRAFT 032filtraquo

Maintenance Record Form Post-Removal Site Control Plan Saco Municipal Landfill Closure

Saco Maine

Complete one form for each day of maintenance activity Note all activities such as grass mowing removal of sediment from channels or slope benches erosion repair seeding and mulching as well as more significant repairs to pipes or rip-rap structures All repairs shall be performed in accordance with the Project Record Drawings and Specifications Repairs to the barrier geomembrane shall only be made after approval by the EPA

Supervisors name Date

Supervisors signature

Weather Temp

Equipment used

Personnel on site

Summary of activities

Unusual conditions or other observations

SIGNIFICANT WEATHER EVENT Post Removal Site Control Plan Saco Municipal Landfill Closure

Saco Maine

~~ Storm Event

Approximate Start TimeApproximate End TimeDuration of storm event hoursPrecipitation from storm inches

Sediment ladden water flowing from Site into Sandy Brook Sediment visible in Sandy Brook upstream of site Sediment visible in Sandy Brook at confluence with Big Ledge Brook

Drainage Structures Note conditions observed

Slope Bench Channels

Date Inspector

Signature

NO YES

Perimeter Drainage Channels

Sediment Retention Basin

Other

Locations of significant erosion

Landfill cap

Perimeter Drainage Channels

Sediment Retention Basin

Other Comments

Inspection Record Form Post-Removal Site Control Plan

Saco Municipal Landfill Closure Saco Maine

Inspectors name Date

Inspectors signature

Weather Temp

I Inspection of Conditions Within Limits of Cover System

A Vegetative Growth and Erosion

General condition of grass (health height presence of woody plants other observations)

Comments on observations (such as dry weather conditions unusual areas etc)

Are there any distinct areas (100 square feet or more) with poor grass growth YES or NO

If YES describe observations and show the location(s) on a copy of the site plan Comments about the area(s)

Is there any noticeable erosion of the grassed areas YES or NO

If YES describe observations and show the location(s) on a copy of the site plan Comments about the area(s)

Saco Municipal Landfill Closure Inspection Recoid Inspectors initials Date

B Slope Bench channels Is there any erosion of soil into the channel rip-rapIs there any damage to the rip-rap supporting geotextile or settlemenAre there any blockages in the bench channelsIs there sedimentation in the channels that reaches a depth of 6 incheAre there any locations in the slope benches where drainage is poor

t

s

YES or NO YES or NO

YES or NO YES or NO

YES or NO If any above answers are YES describe observations and show the location(s) on a copy

of the site plan

C Rip-rap gabion downdrains Is there any erosion of soil into the rip-rap or damage at slope benches YES or NO Is there any damage to the rip-rap or supporting gabions YES or NO Are there any blockages or sediment in the downdrains YES or NO

If any above answers are YES describe observations and show the location(s) on a copy of the site plan

D Other observations

Are there any locations where water can pond on the grass surface YES or NO Are there signs of improper uses (such as vehicle traffic other damage) YES or NO Are there any wet or soft spots YES or NO Are there any signs of soil movement or significant cracks YES or NO

If any above answers are YES describe observations and show the location(s) on a copy of the site plan

Other comments about conditions of the cover system

Page 2 of 8

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

E Perimeter rip-rap drainage zone and outlet pipes

Is there any damage to the perimeter rip-rap drainage zone YES or NO Are there any blockages that could impair their drainage function YES or NO Is there any damage or blockages to the outlet pipes YES or NO

If any above answers are YES describe observations and show the location(s) on a copy of the site plan

F Gas Vents

Are any pipes or pipe boots damaged YES or NO Are any gas vent screens damaged or missing YES or NO Is soil surrounding each gas vent pipe firmly supporting the pipe YES or NO

If any above answers are YES describe observations and identify the number of the gas vent(s) where the identified problem exists

NOTE Annual tilt monitoring to be recorded on attached table See Section V

II Inspection of Conditions Outside Limits of Cover System

A Gabion retaining wall at the entrance to Culvert 1

Is there any damage to this structure YES or NO Are there any blockages in this structure YES or NO Is there sedimentation in the channels that reaches above the invert of the culvert

YES or NO If any above answers are YES describe observations and show the location(s) on a copy

of the site plan

Page 3 of 8

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

Record the tilt of gabion wall by measuring the horizontal distance from the protruding rock about 30 inches above the 6 drain pipe outlet out to the vertical projection of the end of the drain pipe Use a plumb bob or level Distance inches Note any unusual conditions above

B Perimeter drainage channels

Do any channel bottoms show a lack or grass growth or rip-rap to control erosion YES or NO

Are the drainage channels and perimeter areas (to a distance of 20 feet from perimeter rip-rap drainage zone) maintained by cutting grass to control woody vegetation

YES or NO Are there any blockages in these structures YES or NO Is there any erosion (over 2 inches deep) within the channels YES or NO Is there sedimentation in the channels that reaches a depth of 6 inches YES or NO

If any above answers are YES describe observations and show the location(s) on a copy of the site plan

Are there any locations with discoloration in the bottom of the channel that could indicate a leachate seep condition YES or NO

If YES describe observations and show the location(s) on a copy of the site plan

Other comments about conditions of the perimeter drainage channels

Paae 4 of 8

Saco Municipal Landfill Closuie Inspection Record Inspectors initials Date

C Surface diversion channel at southwest corner of landfill

Does the channel bottom show a lack or grass growth or rip-rap to control erosion YES or NO

Is the channel maintained by cutting grass to control woody vegetation YES or NO Are there any blockages in the channel YES or NO Is there any erosion (over 2 inches deep) within the channel YES or NO Is there any damage to the rip-rap at the perimeter channel YES or NO

If any above answers are YES describe observations and provide additional comments

D Culverts manholes rip-rap outlet protection

Are any culvert pipes damaged YES or NO Is there any sedimentation in pipes above a depth of 2 inches YES or NO Are manholes damaged YES or NO Are the rip-rap outlet plunge pools damaged YES or NO

If any above answers are YES describe observations and show the location(s) on a copy of the site plan

E Stormwater Management Basin

Depth of water in basin inches (above) or (below) holes in the bottom of riser structure

Is there evidence of structural damage to the berm YES or NO Is there any damage to the emergency rip-rap overflow area YES or NO Is there sedimentation over 6 inches deep at any locations in the basin YES or NO Is there any damage to the outlet pipe structure YES or NO Are there any very wet or soft areas at the toe of the slopes in the drainage basin

YES or NO If any above answers are YES describe observations and show the location(s) on a copy

of the site plan

Pace 5 of 8

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

Is the relief drain at the toe of slope in the stormwater basin damaged or impaired YES or NO

If YES describe observations

F Other observations

Are there any wet or discolored areas within 100 feet of the perimeter of the landfill that could indicate a leachate seep condition YES or NO

If YES describe observations and show the location(s) on a copy of the site plan

Is there any damage to the access road surface or condition YES or NO

If YES describe observations and show the location(s) on a copy of the site plan

Other comments about conditions of the site outside of the cover system

III Inspection of Sandy Brook Sediment Removal Area

Is there discoloration within the limits of the removal area YES or NO Is the outlet rip-rap discolored YES or NO Is the outlet rip-rap damaged or blocked YES or NO Is there sedimentation or erosion to a depth over 2 inches YES or NO

Page 6 of 8

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

If any above answers are YES describe observations and show the location(s) on a copy of the site plan

Other comments about conditions of the sediment removal area

IV Survey of Settlement Monitoring Locations (annually for NovemberDecember report)

Perform differential level survey of the top of the stainless steel strap at the top of the geomembrane boot at the base of the identified gas vents Record elevations in the following table Attach copy of survey data that determined these elevations

Gas Vent Number Elevation (feet) 7 8 9 10

Other comments about settlement observations or survey conditions

Page 7 of 8

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

V Gas Vent Monitoring (annually for NovemberDecember report)

Record the tilt of each gas vent in the following table Measure the maximum horizontal distance from the vertical projection of the point four feet above the gas vent boot clamp to the boot clamp Use a plumb bob or level to make the vertical projection

Gas Vent Number Vertical distance (inches) Comments 1 2 3 4 5 6 7 8 9

10 11 12 13 14 15 16 17 18 19 20

Page 8 of 8

1. barcode 5301
2. barcodetext SDMS Doc ID 5301

SIGNIFICANT WEATHER EVENT Post Removal Site Control Plan Saco Municipal Landfill Closure

Saco Maine

~~ Storm Event

Approximate Start TimeApproximate End TimeDuration of storm event hoursPrecipitation from storm inches

Sediment ladden water flowing from Site into Sandy Brook Sediment visible in Sandy Brook upstream of site Sediment visible in Sandy Brook at confluence with Big Ledge Brook

Drainage Structures Note conditions observed

Slope Bench Channels

Date Inspector

Signature

NO YES

Perimeter Drainage Channels

Sediment Retention Basin

Other

Locations of significant erosion

Landfill cap

Perimeter Drainage Channels

Sediment Retention Basin

Other Comments

Inspection Record Form Post-Removal Site Control Plan

Saco Municipal Landfill Closure Saco Maine

Inspectors name Date

Inspectors signature

Weather Temp

I Inspection of Conditions Within Limits of Cover System

A Vegetative Growth and Erosion

General condition of grass (health height presence of woody plants other observations)

Comments on observations (such as dry weather conditions unusual areas etc)

Are there any distinct areas (100 square feet or more) with poor grass growth YES or NO

If YES describe observations and show the location(s) on a copy of the site plan Comments about the area(s)

Is there any noticeable erosion of the grassed areas YES or NO

If YES describe observations and show the location(s) on a copy of the site plan Comments about the area(s)

Saco Municipal Landfill Closure Inspection Recoid Inspectors initials Date

B Slope Bench channels Is there any erosion of soil into the channel rip-rapIs there any damage to the rip-rap supporting geotextile or settlemenAre there any blockages in the bench channelsIs there sedimentation in the channels that reaches a depth of 6 incheAre there any locations in the slope benches where drainage is poor

t

s

YES or NO YES or NO

YES or NO YES or NO

YES or NO If any above answers are YES describe observations and show the location(s) on a copy

of the site plan

C Rip-rap gabion downdrains Is there any erosion of soil into the rip-rap or damage at slope benches YES or NO Is there any damage to the rip-rap or supporting gabions YES or NO Are there any blockages or sediment in the downdrains YES or NO

If any above answers are YES describe observations and show the location(s) on a copy of the site plan

D Other observations

Are there any locations where water can pond on the grass surface YES or NO Are there signs of improper uses (such as vehicle traffic other damage) YES or NO Are there any wet or soft spots YES or NO Are there any signs of soil movement or significant cracks YES or NO

If any above answers are YES describe observations and show the location(s) on a copy of the site plan

Other comments about conditions of the cover system

Page 2 of 8

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

E Perimeter rip-rap drainage zone and outlet pipes

Is there any damage to the perimeter rip-rap drainage zone YES or NO Are there any blockages that could impair their drainage function YES or NO Is there any damage or blockages to the outlet pipes YES or NO

If any above answers are YES describe observations and show the location(s) on a copy of the site plan

F Gas Vents

Are any pipes or pipe boots damaged YES or NO Are any gas vent screens damaged or missing YES or NO Is soil surrounding each gas vent pipe firmly supporting the pipe YES or NO

If any above answers are YES describe observations and identify the number of the gas vent(s) where the identified problem exists

NOTE Annual tilt monitoring to be recorded on attached table See Section V

II Inspection of Conditions Outside Limits of Cover System

A Gabion retaining wall at the entrance to Culvert 1

Is there any damage to this structure YES or NO Are there any blockages in this structure YES or NO Is there sedimentation in the channels that reaches above the invert of the culvert

YES or NO If any above answers are YES describe observations and show the location(s) on a copy

of the site plan

Page 3 of 8

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

Record the tilt of gabion wall by measuring the horizontal distance from the protruding rock about 30 inches above the 6 drain pipe outlet out to the vertical projection of the end of the drain pipe Use a plumb bob or level Distance inches Note any unusual conditions above

B Perimeter drainage channels

Do any channel bottoms show a lack or grass growth or rip-rap to control erosion YES or NO

Are the drainage channels and perimeter areas (to a distance of 20 feet from perimeter rip-rap drainage zone) maintained by cutting grass to control woody vegetation

YES or NO Are there any blockages in these structures YES or NO Is there any erosion (over 2 inches deep) within the channels YES or NO Is there sedimentation in the channels that reaches a depth of 6 inches YES or NO

If any above answers are YES describe observations and show the location(s) on a copy of the site plan

Are there any locations with discoloration in the bottom of the channel that could indicate a leachate seep condition YES or NO

If YES describe observations and show the location(s) on a copy of the site plan

Other comments about conditions of the perimeter drainage channels

Paae 4 of 8

Saco Municipal Landfill Closuie Inspection Record Inspectors initials Date

C Surface diversion channel at southwest corner of landfill

Does the channel bottom show a lack or grass growth or rip-rap to control erosion YES or NO

Is the channel maintained by cutting grass to control woody vegetation YES or NO Are there any blockages in the channel YES or NO Is there any erosion (over 2 inches deep) within the channel YES or NO Is there any damage to the rip-rap at the perimeter channel YES or NO

If any above answers are YES describe observations and provide additional comments

D Culverts manholes rip-rap outlet protection

Are any culvert pipes damaged YES or NO Is there any sedimentation in pipes above a depth of 2 inches YES or NO Are manholes damaged YES or NO Are the rip-rap outlet plunge pools damaged YES or NO

If any above answers are YES describe observations and show the location(s) on a copy of the site plan

E Stormwater Management Basin

Depth of water in basin inches (above) or (below) holes in the bottom of riser structure

Is there evidence of structural damage to the berm YES or NO Is there any damage to the emergency rip-rap overflow area YES or NO Is there sedimentation over 6 inches deep at any locations in the basin YES or NO Is there any damage to the outlet pipe structure YES or NO Are there any very wet or soft areas at the toe of the slopes in the drainage basin

YES or NO If any above answers are YES describe observations and show the location(s) on a copy

of the site plan

Pace 5 of 8

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

Is the relief drain at the toe of slope in the stormwater basin damaged or impaired YES or NO

If YES describe observations

F Other observations

Are there any wet or discolored areas within 100 feet of the perimeter of the landfill that could indicate a leachate seep condition YES or NO

If YES describe observations and show the location(s) on a copy of the site plan

Is there any damage to the access road surface or condition YES or NO

If YES describe observations and show the location(s) on a copy of the site plan

Other comments about conditions of the site outside of the cover system

III Inspection of Sandy Brook Sediment Removal Area

Is there discoloration within the limits of the removal area YES or NO Is the outlet rip-rap discolored YES or NO Is the outlet rip-rap damaged or blocked YES or NO Is there sedimentation or erosion to a depth over 2 inches YES or NO

Page 6 of 8

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

If any above answers are YES describe observations and show the location(s) on a copy of the site plan

Other comments about conditions of the sediment removal area

IV Survey of Settlement Monitoring Locations (annually for NovemberDecember report)

Perform differential level survey of the top of the stainless steel strap at the top of the geomembrane boot at the base of the identified gas vents Record elevations in the following table Attach copy of survey data that determined these elevations

Gas Vent Number Elevation (feet) 7 8 9 10

Other comments about settlement observations or survey conditions

Page 7 of 8

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

V Gas Vent Monitoring (annually for NovemberDecember report)

Record the tilt of each gas vent in the following table Measure the maximum horizontal distance from the vertical projection of the point four feet above the gas vent boot clamp to the boot clamp Use a plumb bob or level to make the vertical projection

Gas Vent Number Vertical distance (inches) Comments 1 2 3 4 5 6 7 8 9

10 11 12 13 14 15 16 17 18 19 20

Page 8 of 8

1. barcode 5301
2. barcodetext SDMS Doc ID 5301

Inspection Record Form Post-Removal Site Control Plan

Saco Municipal Landfill Closure Saco Maine

Inspectors name Date

Inspectors signature

Weather Temp

I Inspection of Conditions Within Limits of Cover System

A Vegetative Growth and Erosion

General condition of grass (health height presence of woody plants other observations)

Comments on observations (such as dry weather conditions unusual areas etc)

Are there any distinct areas (100 square feet or more) with poor grass growth YES or NO

If YES describe observations and show the location(s) on a copy of the site plan Comments about the area(s)

Is there any noticeable erosion of the grassed areas YES or NO

If YES describe observations and show the location(s) on a copy of the site plan Comments about the area(s)

Saco Municipal Landfill Closure Inspection Recoid Inspectors initials Date

B Slope Bench channels Is there any erosion of soil into the channel rip-rapIs there any damage to the rip-rap supporting geotextile or settlemenAre there any blockages in the bench channelsIs there sedimentation in the channels that reaches a depth of 6 incheAre there any locations in the slope benches where drainage is poor

t

s

YES or NO YES or NO

YES or NO YES or NO

YES or NO If any above answers are YES describe observations and show the location(s) on a copy

of the site plan

C Rip-rap gabion downdrains Is there any erosion of soil into the rip-rap or damage at slope benches YES or NO Is there any damage to the rip-rap or supporting gabions YES or NO Are there any blockages or sediment in the downdrains YES or NO

If any above answers are YES describe observations and show the location(s) on a copy of the site plan

D Other observations

Are there any locations where water can pond on the grass surface YES or NO Are there signs of improper uses (such as vehicle traffic other damage) YES or NO Are there any wet or soft spots YES or NO Are there any signs of soil movement or significant cracks YES or NO

If any above answers are YES describe observations and show the location(s) on a copy of the site plan

Other comments about conditions of the cover system

Page 2 of 8

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

E Perimeter rip-rap drainage zone and outlet pipes

Is there any damage to the perimeter rip-rap drainage zone YES or NO Are there any blockages that could impair their drainage function YES or NO Is there any damage or blockages to the outlet pipes YES or NO

If any above answers are YES describe observations and show the location(s) on a copy of the site plan

F Gas Vents

Are any pipes or pipe boots damaged YES or NO Are any gas vent screens damaged or missing YES or NO Is soil surrounding each gas vent pipe firmly supporting the pipe YES or NO

If any above answers are YES describe observations and identify the number of the gas vent(s) where the identified problem exists

NOTE Annual tilt monitoring to be recorded on attached table See Section V

II Inspection of Conditions Outside Limits of Cover System

A Gabion retaining wall at the entrance to Culvert 1

Is there any damage to this structure YES or NO Are there any blockages in this structure YES or NO Is there sedimentation in the channels that reaches above the invert of the culvert

YES or NO If any above answers are YES describe observations and show the location(s) on a copy

of the site plan

Page 3 of 8

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

Record the tilt of gabion wall by measuring the horizontal distance from the protruding rock about 30 inches above the 6 drain pipe outlet out to the vertical projection of the end of the drain pipe Use a plumb bob or level Distance inches Note any unusual conditions above

B Perimeter drainage channels

Do any channel bottoms show a lack or grass growth or rip-rap to control erosion YES or NO

Are the drainage channels and perimeter areas (to a distance of 20 feet from perimeter rip-rap drainage zone) maintained by cutting grass to control woody vegetation

YES or NO Are there any blockages in these structures YES or NO Is there any erosion (over 2 inches deep) within the channels YES or NO Is there sedimentation in the channels that reaches a depth of 6 inches YES or NO

If any above answers are YES describe observations and show the location(s) on a copy of the site plan

Are there any locations with discoloration in the bottom of the channel that could indicate a leachate seep condition YES or NO

If YES describe observations and show the location(s) on a copy of the site plan

Other comments about conditions of the perimeter drainage channels

Paae 4 of 8

Saco Municipal Landfill Closuie Inspection Record Inspectors initials Date

C Surface diversion channel at southwest corner of landfill

Does the channel bottom show a lack or grass growth or rip-rap to control erosion YES or NO

Is the channel maintained by cutting grass to control woody vegetation YES or NO Are there any blockages in the channel YES or NO Is there any erosion (over 2 inches deep) within the channel YES or NO Is there any damage to the rip-rap at the perimeter channel YES or NO

If any above answers are YES describe observations and provide additional comments

D Culverts manholes rip-rap outlet protection

Are any culvert pipes damaged YES or NO Is there any sedimentation in pipes above a depth of 2 inches YES or NO Are manholes damaged YES or NO Are the rip-rap outlet plunge pools damaged YES or NO

If any above answers are YES describe observations and show the location(s) on a copy of the site plan

E Stormwater Management Basin

Depth of water in basin inches (above) or (below) holes in the bottom of riser structure

Is there evidence of structural damage to the berm YES or NO Is there any damage to the emergency rip-rap overflow area YES or NO Is there sedimentation over 6 inches deep at any locations in the basin YES or NO Is there any damage to the outlet pipe structure YES or NO Are there any very wet or soft areas at the toe of the slopes in the drainage basin

YES or NO If any above answers are YES describe observations and show the location(s) on a copy

of the site plan

Pace 5 of 8

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

Is the relief drain at the toe of slope in the stormwater basin damaged or impaired YES or NO

If YES describe observations

F Other observations

Are there any wet or discolored areas within 100 feet of the perimeter of the landfill that could indicate a leachate seep condition YES or NO

If YES describe observations and show the location(s) on a copy of the site plan

Is there any damage to the access road surface or condition YES or NO

If YES describe observations and show the location(s) on a copy of the site plan

Other comments about conditions of the site outside of the cover system

III Inspection of Sandy Brook Sediment Removal Area

Is there discoloration within the limits of the removal area YES or NO Is the outlet rip-rap discolored YES or NO Is the outlet rip-rap damaged or blocked YES or NO Is there sedimentation or erosion to a depth over 2 inches YES or NO

Page 6 of 8

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

If any above answers are YES describe observations and show the location(s) on a copy of the site plan

Other comments about conditions of the sediment removal area

IV Survey of Settlement Monitoring Locations (annually for NovemberDecember report)

Perform differential level survey of the top of the stainless steel strap at the top of the geomembrane boot at the base of the identified gas vents Record elevations in the following table Attach copy of survey data that determined these elevations

Gas Vent Number Elevation (feet) 7 8 9 10

Other comments about settlement observations or survey conditions

Page 7 of 8

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

V Gas Vent Monitoring (annually for NovemberDecember report)

Record the tilt of each gas vent in the following table Measure the maximum horizontal distance from the vertical projection of the point four feet above the gas vent boot clamp to the boot clamp Use a plumb bob or level to make the vertical projection

Gas Vent Number Vertical distance (inches) Comments 1 2 3 4 5 6 7 8 9

10 11 12 13 14 15 16 17 18 19 20

Page 8 of 8

1. barcode 5301
2. barcodetext SDMS Doc ID 5301

Saco Municipal Landfill Closure Inspection Recoid Inspectors initials Date

B Slope Bench channels Is there any erosion of soil into the channel rip-rapIs there any damage to the rip-rap supporting geotextile or settlemenAre there any blockages in the bench channelsIs there sedimentation in the channels that reaches a depth of 6 incheAre there any locations in the slope benches where drainage is poor

t

s

YES or NO YES or NO

YES or NO YES or NO

YES or NO If any above answers are YES describe observations and show the location(s) on a copy

of the site plan

C Rip-rap gabion downdrains Is there any erosion of soil into the rip-rap or damage at slope benches YES or NO Is there any damage to the rip-rap or supporting gabions YES or NO Are there any blockages or sediment in the downdrains YES or NO

If any above answers are YES describe observations and show the location(s) on a copy of the site plan

D Other observations

Are there any locations where water can pond on the grass surface YES or NO Are there signs of improper uses (such as vehicle traffic other damage) YES or NO Are there any wet or soft spots YES or NO Are there any signs of soil movement or significant cracks YES or NO

If any above answers are YES describe observations and show the location(s) on a copy of the site plan

Other comments about conditions of the cover system

Page 2 of 8

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

E Perimeter rip-rap drainage zone and outlet pipes

Is there any damage to the perimeter rip-rap drainage zone YES or NO Are there any blockages that could impair their drainage function YES or NO Is there any damage or blockages to the outlet pipes YES or NO

If any above answers are YES describe observations and show the location(s) on a copy of the site plan

F Gas Vents

Are any pipes or pipe boots damaged YES or NO Are any gas vent screens damaged or missing YES or NO Is soil surrounding each gas vent pipe firmly supporting the pipe YES or NO

If any above answers are YES describe observations and identify the number of the gas vent(s) where the identified problem exists

NOTE Annual tilt monitoring to be recorded on attached table See Section V

II Inspection of Conditions Outside Limits of Cover System

A Gabion retaining wall at the entrance to Culvert 1

Is there any damage to this structure YES or NO Are there any blockages in this structure YES or NO Is there sedimentation in the channels that reaches above the invert of the culvert

YES or NO If any above answers are YES describe observations and show the location(s) on a copy

of the site plan

Page 3 of 8

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

Record the tilt of gabion wall by measuring the horizontal distance from the protruding rock about 30 inches above the 6 drain pipe outlet out to the vertical projection of the end of the drain pipe Use a plumb bob or level Distance inches Note any unusual conditions above

B Perimeter drainage channels

Do any channel bottoms show a lack or grass growth or rip-rap to control erosion YES or NO

Are the drainage channels and perimeter areas (to a distance of 20 feet from perimeter rip-rap drainage zone) maintained by cutting grass to control woody vegetation

YES or NO Are there any blockages in these structures YES or NO Is there any erosion (over 2 inches deep) within the channels YES or NO Is there sedimentation in the channels that reaches a depth of 6 inches YES or NO

If any above answers are YES describe observations and show the location(s) on a copy of the site plan

Are there any locations with discoloration in the bottom of the channel that could indicate a leachate seep condition YES or NO

If YES describe observations and show the location(s) on a copy of the site plan

Other comments about conditions of the perimeter drainage channels

Paae 4 of 8

Saco Municipal Landfill Closuie Inspection Record Inspectors initials Date

C Surface diversion channel at southwest corner of landfill

Does the channel bottom show a lack or grass growth or rip-rap to control erosion YES or NO

Is the channel maintained by cutting grass to control woody vegetation YES or NO Are there any blockages in the channel YES or NO Is there any erosion (over 2 inches deep) within the channel YES or NO Is there any damage to the rip-rap at the perimeter channel YES or NO

If any above answers are YES describe observations and provide additional comments

D Culverts manholes rip-rap outlet protection

Are any culvert pipes damaged YES or NO Is there any sedimentation in pipes above a depth of 2 inches YES or NO Are manholes damaged YES or NO Are the rip-rap outlet plunge pools damaged YES or NO

If any above answers are YES describe observations and show the location(s) on a copy of the site plan

E Stormwater Management Basin

Depth of water in basin inches (above) or (below) holes in the bottom of riser structure

Is there evidence of structural damage to the berm YES or NO Is there any damage to the emergency rip-rap overflow area YES or NO Is there sedimentation over 6 inches deep at any locations in the basin YES or NO Is there any damage to the outlet pipe structure YES or NO Are there any very wet or soft areas at the toe of the slopes in the drainage basin

YES or NO If any above answers are YES describe observations and show the location(s) on a copy

of the site plan

Pace 5 of 8

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

Is the relief drain at the toe of slope in the stormwater basin damaged or impaired YES or NO

If YES describe observations

F Other observations

Are there any wet or discolored areas within 100 feet of the perimeter of the landfill that could indicate a leachate seep condition YES or NO

If YES describe observations and show the location(s) on a copy of the site plan

Is there any damage to the access road surface or condition YES or NO

If YES describe observations and show the location(s) on a copy of the site plan

Other comments about conditions of the site outside of the cover system

III Inspection of Sandy Brook Sediment Removal Area

Is there discoloration within the limits of the removal area YES or NO Is the outlet rip-rap discolored YES or NO Is the outlet rip-rap damaged or blocked YES or NO Is there sedimentation or erosion to a depth over 2 inches YES or NO

Page 6 of 8

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

If any above answers are YES describe observations and show the location(s) on a copy of the site plan

Other comments about conditions of the sediment removal area

IV Survey of Settlement Monitoring Locations (annually for NovemberDecember report)

Perform differential level survey of the top of the stainless steel strap at the top of the geomembrane boot at the base of the identified gas vents Record elevations in the following table Attach copy of survey data that determined these elevations

Gas Vent Number Elevation (feet) 7 8 9 10

Other comments about settlement observations or survey conditions

Page 7 of 8

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

V Gas Vent Monitoring (annually for NovemberDecember report)

Record the tilt of each gas vent in the following table Measure the maximum horizontal distance from the vertical projection of the point four feet above the gas vent boot clamp to the boot clamp Use a plumb bob or level to make the vertical projection

Gas Vent Number Vertical distance (inches) Comments 1 2 3 4 5 6 7 8 9

10 11 12 13 14 15 16 17 18 19 20

Page 8 of 8

1. barcode 5301
2. barcodetext SDMS Doc ID 5301

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

E Perimeter rip-rap drainage zone and outlet pipes

Is there any damage to the perimeter rip-rap drainage zone YES or NO Are there any blockages that could impair their drainage function YES or NO Is there any damage or blockages to the outlet pipes YES or NO

If any above answers are YES describe observations and show the location(s) on a copy of the site plan

F Gas Vents

Are any pipes or pipe boots damaged YES or NO Are any gas vent screens damaged or missing YES or NO Is soil surrounding each gas vent pipe firmly supporting the pipe YES or NO

If any above answers are YES describe observations and identify the number of the gas vent(s) where the identified problem exists

NOTE Annual tilt monitoring to be recorded on attached table See Section V

II Inspection of Conditions Outside Limits of Cover System

A Gabion retaining wall at the entrance to Culvert 1

Is there any damage to this structure YES or NO Are there any blockages in this structure YES or NO Is there sedimentation in the channels that reaches above the invert of the culvert

YES or NO If any above answers are YES describe observations and show the location(s) on a copy

of the site plan

Page 3 of 8

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

Record the tilt of gabion wall by measuring the horizontal distance from the protruding rock about 30 inches above the 6 drain pipe outlet out to the vertical projection of the end of the drain pipe Use a plumb bob or level Distance inches Note any unusual conditions above

B Perimeter drainage channels

Do any channel bottoms show a lack or grass growth or rip-rap to control erosion YES or NO

Are the drainage channels and perimeter areas (to a distance of 20 feet from perimeter rip-rap drainage zone) maintained by cutting grass to control woody vegetation

YES or NO Are there any blockages in these structures YES or NO Is there any erosion (over 2 inches deep) within the channels YES or NO Is there sedimentation in the channels that reaches a depth of 6 inches YES or NO

If any above answers are YES describe observations and show the location(s) on a copy of the site plan

Are there any locations with discoloration in the bottom of the channel that could indicate a leachate seep condition YES or NO

If YES describe observations and show the location(s) on a copy of the site plan

Other comments about conditions of the perimeter drainage channels

Paae 4 of 8

Saco Municipal Landfill Closuie Inspection Record Inspectors initials Date

C Surface diversion channel at southwest corner of landfill

Does the channel bottom show a lack or grass growth or rip-rap to control erosion YES or NO

Is the channel maintained by cutting grass to control woody vegetation YES or NO Are there any blockages in the channel YES or NO Is there any erosion (over 2 inches deep) within the channel YES or NO Is there any damage to the rip-rap at the perimeter channel YES or NO

If any above answers are YES describe observations and provide additional comments

D Culverts manholes rip-rap outlet protection

Are any culvert pipes damaged YES or NO Is there any sedimentation in pipes above a depth of 2 inches YES or NO Are manholes damaged YES or NO Are the rip-rap outlet plunge pools damaged YES or NO

If any above answers are YES describe observations and show the location(s) on a copy of the site plan

E Stormwater Management Basin

Depth of water in basin inches (above) or (below) holes in the bottom of riser structure

Is there evidence of structural damage to the berm YES or NO Is there any damage to the emergency rip-rap overflow area YES or NO Is there sedimentation over 6 inches deep at any locations in the basin YES or NO Is there any damage to the outlet pipe structure YES or NO Are there any very wet or soft areas at the toe of the slopes in the drainage basin

YES or NO If any above answers are YES describe observations and show the location(s) on a copy

of the site plan

Pace 5 of 8

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

Is the relief drain at the toe of slope in the stormwater basin damaged or impaired YES or NO

If YES describe observations

F Other observations

Are there any wet or discolored areas within 100 feet of the perimeter of the landfill that could indicate a leachate seep condition YES or NO

If YES describe observations and show the location(s) on a copy of the site plan

Is there any damage to the access road surface or condition YES or NO

If YES describe observations and show the location(s) on a copy of the site plan

Other comments about conditions of the site outside of the cover system

III Inspection of Sandy Brook Sediment Removal Area

Is there discoloration within the limits of the removal area YES or NO Is the outlet rip-rap discolored YES or NO Is the outlet rip-rap damaged or blocked YES or NO Is there sedimentation or erosion to a depth over 2 inches YES or NO

Page 6 of 8

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

If any above answers are YES describe observations and show the location(s) on a copy of the site plan

Other comments about conditions of the sediment removal area

IV Survey of Settlement Monitoring Locations (annually for NovemberDecember report)

Perform differential level survey of the top of the stainless steel strap at the top of the geomembrane boot at the base of the identified gas vents Record elevations in the following table Attach copy of survey data that determined these elevations

Gas Vent Number Elevation (feet) 7 8 9 10

Other comments about settlement observations or survey conditions

Page 7 of 8

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

V Gas Vent Monitoring (annually for NovemberDecember report)

Record the tilt of each gas vent in the following table Measure the maximum horizontal distance from the vertical projection of the point four feet above the gas vent boot clamp to the boot clamp Use a plumb bob or level to make the vertical projection

Gas Vent Number Vertical distance (inches) Comments 1 2 3 4 5 6 7 8 9

10 11 12 13 14 15 16 17 18 19 20

Page 8 of 8

1. barcode 5301
2. barcodetext SDMS Doc ID 5301

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

Record the tilt of gabion wall by measuring the horizontal distance from the protruding rock about 30 inches above the 6 drain pipe outlet out to the vertical projection of the end of the drain pipe Use a plumb bob or level Distance inches Note any unusual conditions above

B Perimeter drainage channels

Do any channel bottoms show a lack or grass growth or rip-rap to control erosion YES or NO

Are the drainage channels and perimeter areas (to a distance of 20 feet from perimeter rip-rap drainage zone) maintained by cutting grass to control woody vegetation

YES or NO Are there any blockages in these structures YES or NO Is there any erosion (over 2 inches deep) within the channels YES or NO Is there sedimentation in the channels that reaches a depth of 6 inches YES or NO

If any above answers are YES describe observations and show the location(s) on a copy of the site plan

Are there any locations with discoloration in the bottom of the channel that could indicate a leachate seep condition YES or NO

If YES describe observations and show the location(s) on a copy of the site plan

Other comments about conditions of the perimeter drainage channels

Paae 4 of 8

Saco Municipal Landfill Closuie Inspection Record Inspectors initials Date

C Surface diversion channel at southwest corner of landfill

Does the channel bottom show a lack or grass growth or rip-rap to control erosion YES or NO

Is the channel maintained by cutting grass to control woody vegetation YES or NO Are there any blockages in the channel YES or NO Is there any erosion (over 2 inches deep) within the channel YES or NO Is there any damage to the rip-rap at the perimeter channel YES or NO

If any above answers are YES describe observations and provide additional comments

D Culverts manholes rip-rap outlet protection

Are any culvert pipes damaged YES or NO Is there any sedimentation in pipes above a depth of 2 inches YES or NO Are manholes damaged YES or NO Are the rip-rap outlet plunge pools damaged YES or NO

If any above answers are YES describe observations and show the location(s) on a copy of the site plan

E Stormwater Management Basin

Depth of water in basin inches (above) or (below) holes in the bottom of riser structure

Is there evidence of structural damage to the berm YES or NO Is there any damage to the emergency rip-rap overflow area YES or NO Is there sedimentation over 6 inches deep at any locations in the basin YES or NO Is there any damage to the outlet pipe structure YES or NO Are there any very wet or soft areas at the toe of the slopes in the drainage basin

YES or NO If any above answers are YES describe observations and show the location(s) on a copy

of the site plan

Pace 5 of 8

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

Is the relief drain at the toe of slope in the stormwater basin damaged or impaired YES or NO

If YES describe observations

F Other observations

Are there any wet or discolored areas within 100 feet of the perimeter of the landfill that could indicate a leachate seep condition YES or NO

If YES describe observations and show the location(s) on a copy of the site plan

Is there any damage to the access road surface or condition YES or NO

If YES describe observations and show the location(s) on a copy of the site plan

Other comments about conditions of the site outside of the cover system

III Inspection of Sandy Brook Sediment Removal Area

Is there discoloration within the limits of the removal area YES or NO Is the outlet rip-rap discolored YES or NO Is the outlet rip-rap damaged or blocked YES or NO Is there sedimentation or erosion to a depth over 2 inches YES or NO

Page 6 of 8

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

If any above answers are YES describe observations and show the location(s) on a copy of the site plan

Other comments about conditions of the sediment removal area

IV Survey of Settlement Monitoring Locations (annually for NovemberDecember report)

Perform differential level survey of the top of the stainless steel strap at the top of the geomembrane boot at the base of the identified gas vents Record elevations in the following table Attach copy of survey data that determined these elevations

Gas Vent Number Elevation (feet) 7 8 9 10

Other comments about settlement observations or survey conditions

Page 7 of 8

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

V Gas Vent Monitoring (annually for NovemberDecember report)

Record the tilt of each gas vent in the following table Measure the maximum horizontal distance from the vertical projection of the point four feet above the gas vent boot clamp to the boot clamp Use a plumb bob or level to make the vertical projection

Gas Vent Number Vertical distance (inches) Comments 1 2 3 4 5 6 7 8 9

10 11 12 13 14 15 16 17 18 19 20

Page 8 of 8

1. barcode 5301
2. barcodetext SDMS Doc ID 5301

Saco Municipal Landfill Closuie Inspection Record Inspectors initials Date

C Surface diversion channel at southwest corner of landfill

Does the channel bottom show a lack or grass growth or rip-rap to control erosion YES or NO

Is the channel maintained by cutting grass to control woody vegetation YES or NO Are there any blockages in the channel YES or NO Is there any erosion (over 2 inches deep) within the channel YES or NO Is there any damage to the rip-rap at the perimeter channel YES or NO

If any above answers are YES describe observations and provide additional comments

D Culverts manholes rip-rap outlet protection

Are any culvert pipes damaged YES or NO Is there any sedimentation in pipes above a depth of 2 inches YES or NO Are manholes damaged YES or NO Are the rip-rap outlet plunge pools damaged YES or NO

If any above answers are YES describe observations and show the location(s) on a copy of the site plan

E Stormwater Management Basin

Depth of water in basin inches (above) or (below) holes in the bottom of riser structure

Is there evidence of structural damage to the berm YES or NO Is there any damage to the emergency rip-rap overflow area YES or NO Is there sedimentation over 6 inches deep at any locations in the basin YES or NO Is there any damage to the outlet pipe structure YES or NO Are there any very wet or soft areas at the toe of the slopes in the drainage basin

YES or NO If any above answers are YES describe observations and show the location(s) on a copy

of the site plan

Pace 5 of 8

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

Is the relief drain at the toe of slope in the stormwater basin damaged or impaired YES or NO

If YES describe observations

F Other observations

Are there any wet or discolored areas within 100 feet of the perimeter of the landfill that could indicate a leachate seep condition YES or NO

If YES describe observations and show the location(s) on a copy of the site plan

Is there any damage to the access road surface or condition YES or NO

If YES describe observations and show the location(s) on a copy of the site plan

Other comments about conditions of the site outside of the cover system

III Inspection of Sandy Brook Sediment Removal Area

Is there discoloration within the limits of the removal area YES or NO Is the outlet rip-rap discolored YES or NO Is the outlet rip-rap damaged or blocked YES or NO Is there sedimentation or erosion to a depth over 2 inches YES or NO

Page 6 of 8

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

If any above answers are YES describe observations and show the location(s) on a copy of the site plan

Other comments about conditions of the sediment removal area

IV Survey of Settlement Monitoring Locations (annually for NovemberDecember report)

Perform differential level survey of the top of the stainless steel strap at the top of the geomembrane boot at the base of the identified gas vents Record elevations in the following table Attach copy of survey data that determined these elevations

Gas Vent Number Elevation (feet) 7 8 9 10

Other comments about settlement observations or survey conditions

Page 7 of 8

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

V Gas Vent Monitoring (annually for NovemberDecember report)

Record the tilt of each gas vent in the following table Measure the maximum horizontal distance from the vertical projection of the point four feet above the gas vent boot clamp to the boot clamp Use a plumb bob or level to make the vertical projection

Gas Vent Number Vertical distance (inches) Comments 1 2 3 4 5 6 7 8 9

10 11 12 13 14 15 16 17 18 19 20

Page 8 of 8

1. barcode 5301
2. barcodetext SDMS Doc ID 5301

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

Is the relief drain at the toe of slope in the stormwater basin damaged or impaired YES or NO

If YES describe observations

F Other observations

Are there any wet or discolored areas within 100 feet of the perimeter of the landfill that could indicate a leachate seep condition YES or NO

If YES describe observations and show the location(s) on a copy of the site plan

Is there any damage to the access road surface or condition YES or NO

If YES describe observations and show the location(s) on a copy of the site plan

Other comments about conditions of the site outside of the cover system

III Inspection of Sandy Brook Sediment Removal Area

Is there discoloration within the limits of the removal area YES or NO Is the outlet rip-rap discolored YES or NO Is the outlet rip-rap damaged or blocked YES or NO Is there sedimentation or erosion to a depth over 2 inches YES or NO

Page 6 of 8

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

If any above answers are YES describe observations and show the location(s) on a copy of the site plan

Other comments about conditions of the sediment removal area

IV Survey of Settlement Monitoring Locations (annually for NovemberDecember report)

Perform differential level survey of the top of the stainless steel strap at the top of the geomembrane boot at the base of the identified gas vents Record elevations in the following table Attach copy of survey data that determined these elevations

Gas Vent Number Elevation (feet) 7 8 9 10

Other comments about settlement observations or survey conditions

Page 7 of 8

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

V Gas Vent Monitoring (annually for NovemberDecember report)

Record the tilt of each gas vent in the following table Measure the maximum horizontal distance from the vertical projection of the point four feet above the gas vent boot clamp to the boot clamp Use a plumb bob or level to make the vertical projection

Gas Vent Number Vertical distance (inches) Comments 1 2 3 4 5 6 7 8 9

10 11 12 13 14 15 16 17 18 19 20

Page 8 of 8

1. barcode 5301
2. barcodetext SDMS Doc ID 5301

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

If any above answers are YES describe observations and show the location(s) on a copy of the site plan

Other comments about conditions of the sediment removal area

IV Survey of Settlement Monitoring Locations (annually for NovemberDecember report)

Perform differential level survey of the top of the stainless steel strap at the top of the geomembrane boot at the base of the identified gas vents Record elevations in the following table Attach copy of survey data that determined these elevations

Gas Vent Number Elevation (feet) 7 8 9 10

Other comments about settlement observations or survey conditions

Page 7 of 8

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

V Gas Vent Monitoring (annually for NovemberDecember report)

Record the tilt of each gas vent in the following table Measure the maximum horizontal distance from the vertical projection of the point four feet above the gas vent boot clamp to the boot clamp Use a plumb bob or level to make the vertical projection

Gas Vent Number Vertical distance (inches) Comments 1 2 3 4 5 6 7 8 9

10 11 12 13 14 15 16 17 18 19 20

Page 8 of 8

1. barcode 5301
2. barcodetext SDMS Doc ID 5301

Saco Municipal Landfill Closure Inspection Record Inspectors initials Date

V Gas Vent Monitoring (annually for NovemberDecember report)

Record the tilt of each gas vent in the following table Measure the maximum horizontal distance from the vertical projection of the point four feet above the gas vent boot clamp to the boot clamp Use a plumb bob or level to make the vertical projection

Gas Vent Number Vertical distance (inches) Comments 1 2 3 4 5 6 7 8 9

10 11 12 13 14 15 16 17 18 19 20

Page 8 of 8

1. barcode 5301
2. barcodetext SDMS Doc ID 5301