BLACK & VEATCHBLACK & VEATCH 6601 College Blvd. Overland Pa*, KS 66211 Tel: (913) 458-2900 USEPA...

BLACK & VEATCH6601 College Blvd.Overland Pa*, KS 66211

Tel: (913) 458-2900

USEPA Region VIIAce Services Site

Mr. Rob WeberUSEPA Region VII90! N. 5th StreetKansas City, Kansas 661 01

Black £ Veatch Special Projects Corp.

KAR 0 o 2CG6U r t D D I V I S I O N

BVSPC Project 044720BVSPC Fi le E . I . 2

March 3, 2006

Subject: EPA Contract No. EP-S7-05-06Task Order #0075Nin th Audi t Report

Dear Mr. Weber:

Enclosed are three copies of the report summar iz ing the n i n t h a u d i t of the City of Colby's operation o l ' theAce Services GWTS. Per EPA's usua l request request, I am sending a copy d i rec t ly to Mr. Ashley A l l e nat KDHE.

Please feel free to ca l l me at (91 3) 45X-6506 if you have any questions or need addi t iona l in format ion .

Sincerely,

BLACK & VEATCH SPECIAL PROJECTS CORP.

Ken WyattSite Manager

KWW

cc: A. A lien ( K D H E )G. Felkner v -s i .

I f, AI

40261946

SUPERFUND RECORDS

IIIIIIIIIIIIIIIIIii

Prepared for:U.S. Environmental Protection AgencyRegion 7901 North 5th StreetKansas City, Kansas 66101

Long Term Response ActionAudit Report No. 9

Ace Services SiteColby, Kansas

March 3, 2006

EPA Contract No.: EP-S7-05-06EPA Task Order No.: 0075.

BVSPC Project No.: 044725.01.49

Prepared by:=TJ BLACK &VEATCH Black & Veatch Special Projects Corp.m=M building a worm of difference- r j r

6601 College Blvd.Overland Park, Kansas 66211

|, building a WOfld of difference1

ENERGY WATER INFORMATION GOVERNMENT

ProfessionalB3 Environmental Engineers, Inc.

Table of Contents

1.0 In t roduc t i on 1-1

2.0 Observations on General System Operation 2-1

2.1 Well Field 2-2

2.2 Treatment Plant 2-6

2.3 Resin Quality and transfer Issues 2-14

IIIIII

3.0 Sampl ing and Record Keeping 3-1

| 4.0 Evaluation of System Performance 4-1

I 5.0 Action Summary 5-1

ITables

• Table 4-1 Selected Flow and Chromium Concentration Data

IFigures

I Figure 4-1 Gallons Treated vs. Chromium Concentration

I

I

I

I

I

IAce Services She 1C-1 044720.01.49

• LIRA A u d i i Report No. 9

1.0 Introduction

As part of Work Order 0075, USEPA Contract no. EP-S7-05-06, Black & Veatch

Special Projects Corp. (BVSPC) is to monitor key plant operations and evaluate the plant

operator's conformance to specified requirements for system operation at the Ace

Services Site, Ground Water Treatment Plant (GWTP) in Colby, Kansas. These

evaluations or audits are to occur on a quarterly basis. The audits include a site visit to

observe the City of Colby operators and obtain key plant operating data. This report

summarizes the findings from the ninth such audit conducted on January 9 through 13,

2005. This report covers the period from October 13, 2006 through January ] 1, 2005.

The results of the first audit are summarized in the Long Term Response Action Audit

Report No. 1, dated November 10, 2003. The results of the second audit are summarized

in Long Term Response Action Audit Report No. 2, dated March 19, 2004. The results of

the third audit are summarized in Long Term Response Action Audit Report No. 3, dated

July 2, 2004. The results of the fourth audit are summarized in Long. Term Response

Action Audit Report No. 4, dated November 19, 2004. The results of the fifth audit are

summarized in Long Term Response Action Audit Report No. 5, dated April 22, 2005.

The results of the Sixth audit are summarized in Long Term Response Action Audit

Report No. 6, dated June 24, 2005. The results of the seventh audit are summarized in

Long Term Response Action Audit Report No. 7, dated August 26, 2005. The results of

the eighth audit are summarized in Long Term Response Action Audit Report No. 8. dated

November 18,2006.

Ace Services Site 1-1 044720.01.49LIRA Audit Report No. 9

2.0 Observations on General System Operation

During the audit site visit (January 9 through January 12, 2006), BVSPC

representatives arrived at the GWTP at around 7:00 A.M. each morning and did not leave

the plant unt i l between 5:00 and 6:00 P.M. each evening. This allowed observation of the

city operators throughout the regular staff hours.

The City staffing of the plant was unchanged from the last several audits. Mr. Jim

Helus with the City of Colby Public Works Department is assigned as the full time

operator for the treatment system. Mr. Helus generally arrives at the treatment plant at

8:00 A.M. and spends the majority of the day tending to the plant and well field systems.

Mr. Helus is occasionally supplemented by other city staff on an as needed basis. A

second operator is often at the plant on Wednesdays to assist with the extra work

associated with collecting, preparing, and shipping the weekly sample splits for off-site

laboratory analysis. Mr. Helus is responsible for system operation Monday through

Friday. Weekend staffing is provided by various other members of the Colby Public

Works Department; however, Mr. Helus remains on-call for plant alarms seven days a

week.

As noted in previous audits, the assignment of a single primary operator is

resulting in good follow-through on maintenance, supplies inventor)', record keeping, and

problem resolution.

The response to alarms during hours that the plant was not staffed was timely and

has improved from previous audit periods. The auto-dialer has been programmed to dial

out all important alarms including tank level alarms. The auto dialer goes through a

progression of phone numbers unt i l a response is obtained. Mr. Helus generally responds

to all off-hours alarms.

The plant, office, storage, and lab areas were clean and very vvell organized.

Organization of the office files and plant storage room is excellent. The operating staff

continues to express positive attitudes regarding the facility and their jobs. Mr. Helus

remains particularly well engaged in his job as plant operator and his skill levels

regarding the more complex plant subsystems continue to improve. Mr. Helus, as well as

other plant staff, frequently call BVSPC for advice and assistance as needed.

Ace Services Site 2-1 044720.01.49LIRA Audi t Report No. 9

Specific details of system operation, including problems noted during the audit,

are provided in the following sections of this report.

2.1 Well Field

As discussed in the previous audit reports, several of the extraction wells had been

shut down to prevent drawing 1,2-dichloroethane (1,2-DCA) from the Hi-Plains Co-op

plume into the ground water treatment system (GWTS). A new granular activated carbon

(GAC) treatment system installed by Kansas Department of Health and Environment

(KDHE) to remove the 1,2-DCA and other volatile organic compounds (VOC) from the

well water prior to entering the GWTP was started on August 24, 2004. Since that date

(including throughout the entire ninth audit period) all wells have been allowed to run

unless a particular well was shut down for some other reason unique to that well.

As discussed in audit report No. 8, the hexavalent chromium concentration at the

east end of the extraction system has fallen well below the cleanup goal of 100

micrograms per liter (ug/L) total chromium. After reviewing the sample data from wells

EX-4s, 4i, 5s and 5i from the October 2005 sampling round, EPA agreed to begin a surge

pumping approach at the east end of the extraction field. Reducing total flow rate from

the well field would extend resin life and save considerable operating cost. The decision

was made to temporarily shut off wells EX-5s and 5i and to reduce flow at EX-4i from

125 gpm to 100 gpm. Well EX-4s had been shut off already due to low water levels.

These changes were made on October 28, 2005. The well flows remained this way

throughout the remainder of the ninth audit period. Samples were taken from wells EX-

4s, 4i, 5s and 5i on January 11, 2006 and analyzed at the GWTP for hexavalent

chromium. The results are shown in the table below. These results indicate a small

rebound of chromium concentrations at well nest 5 (but s t i l l well below the clean-up

goal) and a small reduction at well nest 4 as would be expected. These results were

shared with EPA and the decision was made to leave the pumping scheme the same and

re-evaluate at the time of the tenth audit scheduled for mid April 2006.

Ace Sen-ices Siie 2-2 044720.01.49LIRA Audi t Report No. 9

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WELL

EX-4s

EX-4i

EX-Ss

EX-5i

October 2005

ug/1 chromium

17.9

61

21.6

51

Jan 11, 2006

im/1 chromium

9.0

47

21

68

There had been numerous problems at various well locations that prevented

several individual wells from running during part or all of the fifth audit period. These

are discussed in detail in the fifth audit report. Repair and upgrade activities performed at

the end of the fifth audit period corrected all the problems in the well field and returned

all wells to full operation with the exception of wells EX-2s and EX-4s. Both of these

wells were shut down due to insufficient water level in the well. Well EX-2s has been

shut down due to lack of water since the very begiruling of long term system operation

and is being used as a source of spare parts for other wells.

Water level probes at wells EX-2i, and EX-2d were reading incorrectly and the

flow meter at well EX-3d is malfunction, however these wells were kept running

throughout the ninth audit period with manual compensation. The flow rates at wells

EX-l i and EX- Id were increased during the seventh audit period in response to rapidly

rising hexavalent chromium concentrations in the nearby Ace Recovery Well (ARW).

These wells were left at the higher How rates throughout the ninth audit period.

Ind iv idua l well flows at the end of the ninth audit period were as follows:

Well

EX- l i

EX-ld

EX-2s

EX-2i

EX-2d

EX-3s

EX-3i

Design flow

35 gpm

40 gpm

25 gpm

100 gpm

100 gpm

25 gpm

50 gpm

Actual flow

70 gpm

70 gpm

0 gpm (we

1 00 gpm

1 00 gpm

20 gpm

50 gpm

Ace Services SiteLTRA Audit Report No. 9

i-J 04-1720.01.49

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EX-3d

EX-4s

EX-4i

EX-5s

EX-5i

PWS-8

75 gpm

25 gpm

100 gpm

25 gpm

100 gpm

125 gpm

75 gpm

0 gpm (well off-low water)

100 gpm

0 gpm (off for low chromium)

0 gpm (off for low chromium)

125 gpm

Total flow from the wells was 710 gallons per minute (gpm). Note that this is a

significant reduction from the 875 gpm at the end of the eighth audit period. This

reduction is due entirely to the planned flow reduction at well nests 4 and 5.

A review of sampling records shows that at the beginning of the ninth audit

period, the hexavalent chromium concentration in the composite ground water entering

the GWTP was approximately 185 micrograms per liter (ug/L). This increased to about

269 ug/L then fell gradually to 185 ug/L by the end of the ninth audit period. The

increase was due to the How reductions at well nests EX-4 and EX-5. These wells had

very low hexavalent chromium concentrations and el iminating this flow raised the

composite average.

Problems and anomalies noted regarding operation of the well field are described

below.

1. Flow meter malfunction at well EX-3d. The transmitter on the flow

meter at well EX-3d has stopped functioning. The meter reads zero

flow regardless of the actual flow from the well. There is a spare

transmitter available at the GWTP to replace this unit.

2. Low water at well EX-5s. It was noted during the sixth audit that the

water level at EX-5s was very low and the well could no longer sustain

the design flow rate of 25 gpm. The flow from well EX-5s was reduced

to 20 gpm during the sixth audit period and then further reduced to 15

gpm at the end of the seventh audit period. It was noted during the

eighth filed audit that the water level at EX-5s when pumping at only

15 gpm is drawn down to only 5 fee! above the pump. This may

ult imately result in pump fai lure from air entrained in the water entering

Ace Services SiteLTRA Audit Report No 9

2-4 044720.01.49

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the pump as has happened at other shallow wells. As noted above, well

EX-5s was shut of on October 28, 2005 as part of a new pulse pumping

scheme. BVSPC recommends that the well pump remain shut off as has

been done at wells EX-4s and 2s until the water level rises enough to

allow pumping without endangering the pump. The existing pump in

well EX-5s cannot be turned down much below 15 gpm without

damaging the pump motor. The semi-annual ground water evaluation

will assess the effect of the shut down of EX-5s.

3. Possible inaccurate level probe at wells EX-2i. and EX-2d: The level

probe at well EX-2d has been showing an assumed false low reading of

about 66 feet for several audi t periods however it has held steady and

has not caused a pump shutdown. The new probe installed at well EX-

2i during the eighth audit period is showing a possible low value of 37

feet. The 66 foot value in well EX-2d is consistent with a 37 foot value

at well EX-2i. These values may actually be correct which would

indicate a very low water level at well nest EX-2. The actual level will

be measured during the next scheduled audit in April 2006 to determine

if the level probe readings are in error.

4. Excessive dust in the well houses: As was noted in the seventh audit

report, the lack of filtration for the well house ventilation intakes was

allowing excessive dust to enter the well house during dry windy

weather (which is quite common in Colby, KS). The excessive dust is a

threat to the fiber optic equipment in the well house panels. In the

seventh audit report, BVSPC recommended that the intake louver skirts

be modified by a local HVAC contractor to accommodate a standard

24" x 24" furnace filter between the louver and isolation damper. A bid

was solicited from McK.ee Inc. for this work. The bid price was $125

per well house. McKee completed this upgrade by the end of the ninth

audit period. This was listed as Action item 1 in the eighth audit report.

Ace Services Site 2-5 0447200149LIRA Audit Report No. 9

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5. Stuck motor operated valves at wells EX-21 and PWS-8: During

inspection of the wells at the t ime of the ninth audit period it was noted

that the motor operated valves at wells EX-2i and PWS-8 were stuck

and would not respond to modulating output from the flow controllers.

BVSPC cycled the vales through full range to free them up and they

then began responding properly to position signal input. This has been

a recurring problem at several wells. The plant operators need to

occasionally cycle all the well flow control valves as part of routine

maintenance lo prevent the valves from ceasing in position. This has

been brought up in earlier audit reports.

6. Malfunctioning, How controller at well EX-4i: The flow controller at

well EX-4i is not output t ing the correct positioning signal for the

selected set point when in automatic mode. This uni t needs repair or

replacement.

2.2 Treatment Plant

The treatment plant ran continuously throughout the ninth audit period. The

treatment system was operated at near ful l normal capacity 700 to 800 gpm throughout

the ninth audit period. Table 4-1 provides a day-by-day accounting of total plant flow

throughout the ninth audi t period.

As noted in previous audit reports, the GAC system does not appear to have had

any significant impact on the GWTS with the exception of occasional clogging of the bag

filters with carbon fines (particularly when the GAC beds are backwashed) and

elimination of the hexavalent chromium loading to the GWTP for several days when a

fresh GAC bed is brought on line. A fresh GAC bed was brought on line on October 28,

2005 and again on December 7, 2005. Each time the fresh GAC removed the hexavalent

chromium from the groundwater for several days so the GWTP influent chrome load was

zero (see table 4-1 for details)

Ace Services Site 2-6 044720.01.49I.TRA Aud i t Report No. 9

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There were two major upsets during the seventh audit period involving the ion

exchange resin. These events are detailed in section 2.3 of the seventh audit report.

Several investigations and filed trials were conducted during the eighth audit period to

determine a permanent resolution to the resin issues. These results of these investigations

are presented in section 2.3 of this eighth audit report. BVSPC had the opportunity to

observe and critique a resin exchange during the ninth filed audit. Observations as well

as follow up regarding resin issues are provided in section 2.3 of this ninth audit report.

The appearance of a significant water hammer when the city water transfer pumps

shut off first appeared at the beginning of the eighth audit period resulting in breakage of

several components in the PVC chlorine feed loop piping. This problem was described in

detail in the eighth audit report. This issued continued to be problem throughout the

ninth audit period but was finally resolved by the end of the ninth audit period. Complete

details of the final resolution are provided below.

Overall the GWTP treated approximately 96.2 mil l ion gallons during the ninth

audit period averaging about 1,058,000 gallons per day (gpd).

Milestones for resin management activities were as follows.

TRAIN A:

October 13, 2005 - Beginning of ninth audit period. Bed Al is lead,

A2 is lag (Train A has been in this configuration the since September

14,2005).

- October 26, 2005 - Beds advanced to put A2 in lead and A3 in lag.

Note bed A3 is the first bed of Dow SAR placed on-line.

- November 17, 2005 - New resin is placed in bed Al (Dow SAR at

approximately 35% bicarbonate)

December 23, 2005 - Beds advanced to put A3 in lead and A] in lag.

January 11, 2006 - End of ninth audi t period. New resin is placed in

Bed A2. Bed A3 is lead and Bed Al is lag.

Ace Sen-ices Site 2-7 044720.01.49LTRA Audit Report No. 9

TRAIN B:

- October 12, 2005 - Beginning of ninth audit period, Bed Bl is lead,

B2 is lag (Train B has been in this configuration since September 14,

2005).

- October 26, 2005 - Beds are advanced to put B2 in lead and B3 in lag.

- November 17, 2005 - Resin is replaced in bed Bl (Dow SAR,

approximately 35% bicarbonate)

December 23, 2005 - Beds advanced to place B3 in lead and Bl in lag.

- October 12, 2005 - End of ninth audit period. Fresh resin is placed in

bed B2. Bed B3 is lead and Bed Bl is lag.

The status of the treatment system as of the end of the ninth audit period was both

trains operating at approximately 355 gpm with Beds A3 and B3 in lead and Beds Al and

Bl in lag service. Stand-by Beds A2 and B2 had fresh resin. As noted in previous audit

reports, the resin service contract with US Filter (USF) has been renewed and required a

switch from Purolite A300 to Dow SAR resin. The resin in beds A2 and B2 were the last

beds to be replaced with the new Dow SAR resin. Beds A3 and B3 were the first beds to

be loaded with Dow SAR. As of the end of the ninth audit period these beds were in lead

position so no treatment performance data is yet available for Dow SAR. It is anticipated

that these two beds will exhaust in late February or early March 2006 during the tenth

audit period.

A few problems and anomalies were noted regarding plant operation during the

ninth audit period. These are described below.

]. Resin quality and delivery issues. There were two incidents when the

effluent water quality from lag beds that had just been placed in service

was not suitable for use as dr inking water due to low pH excursions and

organic contaminants. One incident occurred on May 25, 2005 during

the seventh audit period and the other occurred on July 20, 2005 just at

the beginning of the eight audit period. These problems have been

resolved by switching resin supply and instituting a stronger resin

Ace Services Sne 2-8 044720.01.49LIRA Aud i t Report No. 9

IIIIIIIIIIIIIIIIIII

quality control program. Details regarding these incidents including

resolutions for this problem are provided in section 2.3 of the seventh

audit report and section 2.3 of the eighth audit report. Section 2.3 of

this ninth audit report addresses observations made during a resin

transfer event conducted during the ninth field audit.

2. Plant ventilation fan EF-2 not functioning. It was noted during the

ninth field audit that plant ventilation exhaust fan EF-2 would not start

even with the H-O-A switch in the '"Hand" position. A brief

investigation revealed a loose wire from the motor starter. The wire

was reconnected and the fan tested properly.

3. Leaking pressure gauges. The pressure gauge on Train A Bed 2

developed a small leak. The gauge was repaired with silicone sealant.

This is at least the third instance of leaking pressure gauges on the

process trains. The previous leaks required replacement of the gauge.

If this trend continues it would be advisable to replace leaking gauges in

the future with an upgraded model.

4. Damaged conductivity meters and probes. As was noted in the fourth

audit report, the conductivity meters on both ion exchange trains were

flashing error and out of range. As noted in the fifth audit report, it was

determined that the conductivity measurement probes were ruined

because they had not been kept wet when the treatment trains are

drained. Plans were made to order new probes plus new hot tap probe

mounts that will allow the probes to be pulled while the system is still

operating and under pressure. At the time of the sixth field audit, this

modification had not yet been done, primarily due to delays in acquiring

the new probes and equipment from Pedrotti Controls. By the end of

the seventh audit period, the new probes and pipe fittings had been

received at the plant but not yet installed. As of the end of the ninth

Ace Services Site 2-9 0-44720.OM9LIRA Aud i t Report No. 9

IIIIIIIIIIIIIIIIIII

audit period, the installation had still not been done. This was listed as

action item 2 in the fifth, sixth, seventh and eighth audit reports.

5. Valve position switch out of adjustment. The "valve open" micro

switch on the treated water outlet valve on Bed Al (valve FV-10102)

was not making contact when the valve reached full open causing a

PLC alarm. The switch plunger was extended so that good contact

would be made and this corrected the problem.

6. Broken ion exchange vessel vent piping. While transferring spent

resin out of a vessel it is necessary to vent air pressure out of the bed.

The vent piping coming down the side of the bed is stainless steel.

Short sections of PVC pipe extend the bottom of the vent lines over to

the trench drains. During the resin transfer out of bed B2 on February

11, 2006 the PVC piping burst due to the pressure pulse caused by the

sudden opening of the vent valve. This has happened several times in

the past so that most of the PVC sections on all six beds have been

patched or repaired. Following the incident on February 11, 2006

BVSPC recommended the all the PVC sections be replaced with l ike

sized schedule 40 galvanized piping to permanently resolve this

recurring problem. A bid was acquired from a local p lumbing shop for

this work in the amount of $2480.00 for all six beds. It is anticipated

that this upgrade will occur during the tenth audit period.

7. Effluent tank transmitter malfunction: Early in the morning (about

4:00 am) on December 8, 2005 the GWTP shut down due to a false

high level alarm on the effluent tank. The effluent was not, in fact at

high level. The overnight temperature had dropped below zero and

frost had formed on the transmitter head causing the transmitter to see a

false high tank level. This has happened several times in the past

during cold weather. FJeat tracing was added to the tank nozzle through

Ace Services Site 2-10 044720.01.49LIRA A u d i t Repon No. 9

IIIIIIIIIIIIIIIIIII

which the level transmitter mounts to try to eliminate this problem.

This solution has been par t ia l ly successful. Although the problem still

occurs it requires a much lower ambient temperature of several degrees

below zero. ]t may be that additional heat trace turns would be

warranted to completely eliminate the problem.

8. Water hammer and related modificat ions to the chlorine loop. Mid-

evening on October 11, 2005 the city water transfer pump TWP-1

started and then stopped abruptly. When the pump stopped, a water

hammer of extreme intensity occurred in the city water discharge

system. This was the first observed instance of a strong water hammer

in this system. Follow this in i t i a l incident, the water hammer continued

to occur every time the city water transfer pumps shut off. A full

accounting of the water hammer problem and related damage to

elements of the chlorine loop piping is provided in the eighth audit

report. Damage included cracking the chlorine ejector, fracture of a

ball valve in the piping system and breaking of a fitting in the buried

portion of the chlorine booster loop. Each of these breakages occurred

in separate incidents. As explained in the eighth audit report, BVSPC

recommended adding a bladder style surge arrestor to the chlorine loop

to prevent further damage and rerouting of the chlorine loop to keep all

the piping above ground where repairs would be more easily made.

EPA ultimately approved these proposals and the work was completed

during the time of the ninth field audit as described below.

A 40 gallon, bladder type surge arrester was special ordered from Fluid

Kinetics with a fluorocarbon bladder and special interior coating to

withstand service in high concentrations of chlorine. The arrestor was

delivered directly to the GWTP complete with a floor stand, all

necessary valves and gages and a 4 inch ASN1 class 150 bottom

connecting flange to allow easy connection to the chlorine loop CPVC

Ace Services Site 2-11 044720.01.49LIRA A u d i t Report No. 9

IIIIIIIIIIIIIIIIIII

piping. The chlorine loop was re-piped by the city of Colby operators

with the help from BVSPC on January 11, 2006. The new piping

configuration relocated the chlorine vacuum ejector from the chlorine

shed to inside the GWTP. The chlorine vacuum feed hose was routed

from the chlorine feeder in the chlorine shed through a 1 inch RGS

conduit into the GWTP and reconnected to the relocated ejector.

Connection of this new piping to the surge arrester was done on January

12, 2006. There were no significant problems with this installation

however the conduit between the chlorine shed and the GWTP needs to

be insulated.

The surge arrester bladder was charged to 100 psi and system was

started up, allowed to settle into equi l ibr ium and then shut down. A

water hammer of moderate intensity occurred on shut down and the

piping in the chlorine was notably displaced. The surge bladder was

bled down to 80 psi and the test was conducted a second time. Another

moderate water hammer occurred in the city water discharge system

however the surge arrester damped this to less than a 10 psi surge in the

chlorine loop thus proving it's effectiveness in protecting the chlorine

loop piping and equipment. Set up and testing of the arrester was

managed by BVSPC.

With the chlorine loop now protected from damage, the city water

system was cycled several times while adjusting the closing speed

control on discharge valve CV-6 in an attempt to reduce the intensity of

the water hammer. As expected, the slower the valve was closed, the

less severe the water hammer became. The valve was eventually set to

such a slow closing speed that the 30 second "valve fails to close"

alarm delay in the PLC expired and the valve failure alarm annunciated.

BVSPC reprogrammed the PLC delay to 60 seconds so the closing

speed of valve CV-6 could be reduced even further without triggering

Ace Services Site 2-12 04-1720.01.49LIRA Audit Report No. 9

an alarm. Note: only the alarm delay for CV-6 was altered. All other

valve alarms remained unchanged. The closing speed of CV-6 was then

set as slow as the actuator would allow and the city water discharge

system was cycled on the off. This reduced the water hammer to a

slight bump that should not be a threat to any system connected to the

city discharge.

The ult imate cause of the water hammer is unknown, however it first

occurred when the new city water supply well PWS-15 was first

brought on line in October of 2005. This new well and the GWTP city

water transfer pumps both feed the same city water main, thus the

velocity in the main has been increased which would increase the

severity of a water hammer. Also, it was noted that when the city water

transfer pumps first start it takes several seconds for the flow to

equalize as though there is a large air pocket in the distribution system.

The presence of such an air pocket could store up the energy needed to

create a water hammer. It is unknown if the water hammer is related to

well PWS-15 or if there is an air pocket in the system.

Significant changes or upgrades to the treatment plant during the ninth audit

period included addition of the surge arrestor to the chlorination loop, rerouting the

chlorine loop to locate the ejector inside the GWTP and retiming the closing speed of

valve CV-6 to try to minimize the water hammer. Upgrades planned for the Tenth audit

period include the addition of hot taps for the conductivity probes and installation of new

conductivity transmitters as well as installation of galvanized steel ion exchange vent

piping.

Operator follow-through to address problems at the plant has been excellent.

Ace Services Site 2-13 044720.01.49LIRA Audi t Repon No. 9

2.3 Resin Quality and Transfer Issues

Section 2.3 of the seventh and eighth audit reports summarized significant water

quality incidents related to poor resin qual i ty as well as the ultimate resolution for these

problems. In summary, the resin received at the GWTP on two occasions was

inadequately rinsed and leached unacceptable levels of organics into the process water.

Investigations into this problem identified a second problem of excessive downward pH

shift when a fresh resin bed was placed on line unt i l the resin reached equilibrium for

bicarbonate. Several resin column tests were conducted at the GWTP to determine the

extent of these problems and the most cost effective solution. The details of all of this

work are r u l J y explained in section 2.3 of the seventh and eight audit reports.

The final solution was a renegotiation of the US Filter resin supply contract to

provide virgin Dow SAR resin in place of the Purolite A300 resin in the original contract.

The new contract also requires very stringent QC testing to insure that the resin is free of

residual organics. The new QC program requires that each batch of resin be subjected to

a 16 hour hot water soak test with a limit of 10 parts per million (ppm) total organics

(TOC) in the leachate. Addi t ional ly each resin tanker composite sample for the first ten

loads of Dow SAR is to be put through the entire FDA testing protocol (21 CFR 173.25)

certifying that the resin is fit for a drinking water application. The first ten full FDA

protocols will provide a correlation between the 16 hour screening teat results and the full

FDA testing results so that the 16 hour test can be used alone as the base QC tool. At

least four full FDA tests will be conducted per year to assure the relationship between the

two tests is still valid. The final provision of the new resin service contract requires that

the resin be delivered pre-converted to 35% bicarbonate form to eliminate the

unacceptable pH shift.

At the time of the ninth field audit, a total of six beds of resin had been delivered

under the new contract requirements. Every tanker has easily passed the new QC testing

requirements. The Dow resin has proven to be exceptionally clean. The first beds to be

charged with the Dow SAR resin were beds A3 and B3. At the time of the ninth field

audit these two beds were in the lead position, but had not yet reached breakthrough.

This is expected to occur some time in March 2006. It is anticipated lhal the DOW resin

wi l l provide a longer bed service life to breakthrough than the Purolite resin. The actual

Ace Services Site 2-14 044720.0).-49LIRA Aud i t Report No. 9

IIIIIIIIIIIIIIIIIII

performance of the DOW resin will not be known until beds A3 and B3 reach

breakthrough. The one problem with resin supply under the new contract agreement is

that the City of Colby is not receiving the required testing certificates of compliance from

US Filter prior to the resin being delivered to the GWTP.

During the ninth field audit the BVSPC site manager had an opportunity to watch

a resin exchange event when new resin was placed in beds A2 and B2. US Filter

provides all the labor for the resin transfers as part of the resin supply contract. A few

observations were made that could improve this process as follows:

1. It was noted that the tractor rigs were late model, clean and well

maintained. Also the driver-operators were very professional and

helped the US Filter personnel a great deal with the resin transfers in

and out of the tankers. The tankers themselves are owned by US Filter

and looked old and appeared to be poorly maintained. There were

several leaks noted in the water and air piping at the back of the tanker

and in one tanker the interior rear spray bar was inoperative resulting in

a significant amount of resin remaining in the tanker. This resin had to

be manually moved.

2. The US Filter operators were in a great rush to get the resin transfers

completed and in their haste they over pressured bed A2 running the

pressure in the vessel up as high as 100 psi while attempting to sluice

out the resin. This caused the sluice hose to clog solid with resin as

well as clogging the resin slurry distr ibution pipe in the tanker. The

clogs had to be cleared by disconnecting the hoses and running a

garden hose with a spray nozzle into the sluice hose from the far end to

break up the clogs. The same procedure was used to free up the tanker

distribution pipe. The beds should not be pressured beyond about 30 to

35 psi for resin transfers.

Ace Services Site 2-15 0-4-1720.01.49LIRA Audi! Repon No. 9

IIIIIIIIIIIIIIIIIII

The resin transfer uses a tremendous amount of compressed air. At the

pace that US Filter conducts the transfer operation; the air usage

exceeds what the GWTP compressed air system can provide. This then

requires that GWTP be shut down during resin transfer operations

because there is not sufficient air left to operate the plant valves and

keep the treatment process on line. This situation is made somewhat

worse by the air leaks in the tanker piping. The problem is generally

managed by starting with the influent tank at a very low level and

attempting to get the resin transfer completed and the plant back on-line

before the influent tank fills and the well field has to be shut down.

The only way to accomplish this is to do the resin transfers for two

trains on different days. Accomplishing the transfer for both trains on

the same day generally results in shut down of both the GWTP and the

well field. Since this is a long term problem consideration should be

given to replacing the existing reciprocating compressor with a turbine

type un i t wi th the capacity to supply air for resin transfers and plant

operation simultaneously.


IIIIIIIIIIIIIIIIIII

3.0 Sampling and Record Keeping

As part of the audit, the in-plant records kept by the City operators were reviewed

for completeness and conformity to requirements. During the review, emphasis was

placed on water flow and chromium concentration data that are critical to evaluation of

treatment system performance. The dai ly records were well organized in notebooks kept

at the plant. The daily records were organized by month and date and were complete and

easy to access. The City operators have continued to enter the flow meter totalizer

readings and sample analysis results in Excel spreadsheets to facilitate trend tracking and

quick data retrieval. The sample record sheets have been expanded to include free

chlorine results now when the discharge to the city water system is active.

The operators have continued to fill out the new GAC system log sheet each day.

This new log sheet records critical flow and pressure data for the new GAC system.

During the eighth audit periodic samples taken and analyzed by KDHE from the

GAC system upstream of the GWTP indicated the possibility of the presence of trivalenl

chromium in the raw groundwater. This would be a significant problem since the anion

resin used at the GWTP cannot remove trivalent chromium. A careful review of the

influent water sample results from the GWTP show no indication of any trivalent

chromium. In addition, effluent samples from the GWTP sent for laboratory analysis

indicates that there is no detectable chromium in the effluent of any species (total chrome

analysis). Any measurable amount of t r ivalent chromium in the GWTP influent would

show up in total chromium analysis of the GWTP effluent. As a precaution, daily plant

sampling protocol was revised during the ninth audi t period to require that the regular

morning plant influent sample be analyzed on-site for both total and hexavalent

chromium. A total value in excess of the hexavalenl value would indicate the possibility

of trivalent chromium in the influent. A review of the sample data from the ninth audit

period shows no indication of any trivalent chromium entering the plant.

The City operating staff has done an excellent job with the sampling and record

keeping requirements during the ninth audit period. Two significant irregularities were

noted in the audit and subsequent review of records. These are described below:


IIIIIIIIIIIIIIIIIII

1. Mismatch between on-site and off-site sample results. The hexavalent

chromium concentration data at the GWTP influent (sample locations

SC-1 and SC-2) are often higher in the off-site laboratory analysis than

those recorded from in-plant analysis. This trend was also noted in the

eighth audit report. If this trend continues it may be necessary to

replace the GWTP lab spectropholometer.

2. Bad reagent pillo_ws: It was discovered on December 16, 2005 that

some of the reagent pillows used to test for hexavalent chromium on

the Hach unit contained the wrong reagent even though they were

labeled for hexavalent chromium. These pillows were turning the

water yellow instead of purple and even the clean effluent samples

were changing color. New regent pillows were ordered for the Hach

uni t and they were received on December 21, 2005. The Hanna unit

was used alone during the time waiting for new pillows for the Hach

uni t so no samples were missed.

There have been no significant changes regarding plant sampling and record

keeping during the ninth audit period with the exception of adding once dai ly total

chromium analysis at sample location SC-1.

Ace Services Site J-2 044720.01.49LIRA Audi t Report No. 9

4.0 Evaluation of System Performance

The new GAC system constructed by KDHE was started on August 24, 2004

(during the fourth audit period). Data were closely monitored during the ninth audit

period to determine if there were any significant impacts on the GWTS as a result of the

GAC system being on line. The only day-to-day impacts noted were the occasional

loading of carbon fines on the bag filters and the addit ional head pressure required of the

extraction pumps to push through the GAC beds. When a new GAC bed is first placed

on line it will remove the hexavalent chromium for several days. New GAC beds were

placed on line on October 29, 2005 and again on December 8, 2005. The effect on

hexavalent chromium in the GWTP influent can be seen in Table 4-1.

The ability to capture and control the chromium plume in the ground water is

periodically assessed via sampling and ground water elevation measurement. These data

are analyzed and the findings summarized in semi-annual Cleanup Status Reports. The

most recent report (Cleanup Status Report Number 5, dated December 2, 2005) indicates

that the extraction wells are providing good plume containment and capture.

Selected flow and sampling data from October 13, 2005, through January 11,

2006, are presented in Table 4-1. Table 4-1 also shows the amount of hexavalent

chromium removed by the treatment system. As shown in Table 4-1, the concentration of

hexavalent chromium in the raw water entering the treatment system during the ninth

audit period began at about 185 ug/1 in mid October, rose to a high of 269 ug/1 in mid

November after wells EX-5i and 5s were shut off and flow from well EX-4i was reduced

and then trended back down to about 185 ug/1 by early January.

The data show that the system treated 96.2 mil l ion gallons from October 13, 2005,

through January 11, 2006: 48.1 mi l l i on gallons in Train A and 48.1 mil l ion gallons in

Train B. A total of 60.1 kilograms (kg) (132.5 pounds) of chromium were removed

during this period. Four beds of ion exchange resin (Beds Al, A2, Bl and B2) were

exhausted during this period as shown in Table 4-1. The resin performance for each of

the exhausted beds is shown below:

Bed Al: 30.77 mil l ion gallons: 48.12 Ibs chromium: 36.38 gr/cf*

Ace Semces Site 4-1 044720.U1.49LIRA Aud i t Report No. 9

IIIIIIIIIIIIIIIIIII

Bed B]: 29.52 mi l l ion gallons: 45.64 Ibs chromium: 34.50 gr/cf*

Bed A2: 29.75 millions gallons: 37.15 Ibs of chromium: 28.08 gr/cf*

Bed B2: 29.67 million gallons: 37.02 Ibs of chromium: 27.98 gr/cf*

* gr/cf = grams of chromium per cubic foot of resin

The relative performance data from the previous periods are shown below along

with the data for Beds Al, A2, Bl and B2 from this audit period. Data from the early

periods are shown as an average per 550 cubic foot bed of resin.

Performance test:

First audit period:

Second audit period:

Third Audit Period:

Fourth Audit period:

Bed A3:

BedB2

Bed B3

Fifth Audit period:

Bed Al

BedBl

Bed A2

BedB2

Sixth Audit Period:

Bed A3

BedB3

Seventh Audit Period:

BedAl

BedBl

Bed A2

BedB2

Ace Services SiieLIRA Audit Report No. 9

20.5 mi l l ion gal:

27.0 million gal:

32.5 mill ion gal:

32.3 million gal:

3 1.1 mill ion gal:

31.1 mi l l ion gal:

33.9 mi l l ion gal

25.72 m i l l i o n gal

25.35 mill ion gal

40.37 mil l ion gal

30.71 mill ion gal

32.04 mil l ion gal:

35.08 mi l l i on gal:

27.74 mil l ion gal

26.75 mi l l ion gal

30.13 million gal

30.11 mil l ion gal

4-2

121.4 gr/cf*

93.6 gr/cf*

51.2 gr/cf*

41.9 gr/cf*

71.3 5 gr/cf*

34.28 gr/cf*

29.53 gr/cf*

75.1 gr/cf*

88.18 gr/cf*

90.81 gr/cf*

73.06 gr/cf*

57.67 gr/cf*

63.87 gr/cf*

36.14 gr/cf*

34.86 gr/cf*

42.62 gr/cf*

42.54 gr/cf*

04-1720.01.49

Eighth Audit Period:

Bed A3 29.44 mil l ion gal 41.61 gr/cf

BedB3 29.11 million gal 41.14 gr/cf*

Ninth Audit Period

Bed Al 30.78 million gal 36.38 gr/cf*

Bed B1 29.52 mil l ion gal 34.50 gr/cf

Bed A2 29.75 mil l ion gal 28.08 gr/cP

Bed B2 29.67 mill ion gal 27.98 gr/cP

* gr/cf = grams of chromium per cubic foot of resin

The chromium holding capacity of the resin is expected to diminish with

diminishing influent hexavalent chromium concentrations due to the lower equilibrium.

This is clearly seen in the data above as well as in Figure 4-1. More gallons of water are

treated with the same 550 to 600 cubic feet of resin but at d iminishing resin holding

capacity.

During the entire period of time covered by the second and third audits, the wells

with the highest chromium concentrations were shut down awaiting design and

completion of the GAC system. During that time, chromium concentrations entering the

GWTP were averaging only around 120 to 150 ug/L. Once the GAC system was brought

on line in late August 2004 and all the extraction wells were restarted, the influent

chromium concentrations jumped up to as high a 700 ug/L and have been dropping

steadily since but the chromium concentration is still holding above the low levels seen in

the second and third audit periods. The affects of this can be seen in the higher grams per

cubic foot holding capacity of the resin late in the fourth audit period (Bed A3) and

throughout the fifth audit period. Chromium concentration in the influent ground water

continued to drop during the eighth audit period to around 185 ug/L by the end of the

period and remained near that level through much of the ninth audit period, which is only

a little higher than the very low levels seen during the second and third audit periods and

very similar to the concentration during the sixth and seventh audit periods. Note that the

total gallons treated per bed during the sixth audit period are very similar to the results

Ace Services Site 4-3 04J720.01.49l.TRA Audi t Report No. 9

during the second and third audit periods. Total gallons treated during the seventh,

eighth, and nin th audit periods are substantially lower than during the second, third and

sixth periods even though the inf luent chromium concentrations were similar. There is

no obvious reason for this poor performance. As noted in section 2.3 above, there have

been significant issues regarding the quality and condition of the resin supplied to the

GWTP during the seventh and eighth audit periods. The last batches of Purolite A300

(Beds Al, A2, Bl and B2) were cycled out of service during the ninth audit period. The

first batches of Dow SAR (beds A3 and B3) will cycle through lead service during the

tenth audit period. The treatment performance of the new resin will be closely

monitored. It is anticipated that the Dow SAR resin wi l l show improved performance.

As the hexavalent chromium concentration drops, a point is eventually reached

where the gallons treated by a given amount of resin will no longer increase. This is due

to the presence of other anions in the inf luent water that take up resin exchange capacity.

The data presented above suggest that a 600 cubic foot volume of resin cannot treat more

than 31 to 34 million gallons of Colby ground water regardless of hexavalent chromium

concentration. Bed A2 in the fifth audi t period is an obvious exception, treating over 40

mil l ion gallons at a fairly high chromium loading rate. A possible explanation is that the

bed was loaded with more than the usual 600 cubic feet of resin. Each bed has a total

volume of 1100 cubic feet and is intended to run only half full of resin to allow plenty of

head space for air bump and backwash operations. If 650 to 700 cubic feet of resin were

loaded into the bed there would be no indication of the extra resin except a slightly higher

pressure drop through the bed. A review of the pressure drop data during the time that

Bed A2 was in lead position does in fact show a pressure drop that is consistently 20% to

30% greater than the other bed in the same train. Based on the data it is very likely that

Bed A2 contained 650 to 700 cubic feet of resin during its run in the fifth audit period.

This data point is not included in Figure 4-1 since it is not representative.

Figure 4-1 is a plot of gallons of water treated by an ion exchange bed vs. the

average chromium concentration of the water treated by the bed before significant

chromium breakthrough. This figure very clearly depicts the trends and l imits noted

above. As seen in Figure 4-1, the gallons of water treated increases as the chromium

loading decreases in almost a linear relationship. However, once the average chromium

Ace Services Site 4-4 044720.01.49LIRA Audit Report No. 9

concentration in the GWTP influent water drops below about 300 ug/L, no more increase

in the gallons treated per bed is seen. Every bed with an average chromium influent

concentration below 350 ug/L treated between 31 and 35 mil l ion gallons of water (except

during the seventh and eighth and ninth audit periods while resin quality issues were

encountered) with no correlation to chromium concentration. This can be used as

planning tool for scheduling bed change-outs. Unless the influent chromium

concentrations again rise above 350 ug/1, each bed can be anticipated to treat 33 +/- 2

mill ion gallons of water. The change to Dow SAR resin may or may not have an impact

on this value.

Ion exchange is often used as a polishing process in water treatment because it is

very cost efficient compared to other treatment technologies at low contaminant

concentrations. The relatively low concentration of hexavalent chromium seen in the

composite inf luent groundwater is an excellent application for ion exchange. The total

resin cost inc luding transportation and disposal was 0.162 cents per gallon of water

treated for the ninth audit period. This up from the .0152 to 0.155 cents per gallon from

the seventh and eighth audit periods. This cost is up considerably from 0.130 cents per

gallon during the sixth audit period when the average chromium loading was essentially

the same and is further evidence of poor resin performance dur ing the seventh, eighth and

nin th audi t periods. This is s t i l l a significant reduction from 0.210 cents per gallon from

the performance test and 0.166 cents per gallon from the first audit period when average

chromium concentrations were higher. This diminishing cost as the chromium loading

drops demonstrates the efficiency of the ion exchange process in this application. There

is not sufficient data at this lime to determine the total cost per gallon to treat the

extracted ground water including labor and plant utilities.

It should be noted that all the cost data presented above are based on a resin cost

of $80.70 per cubic foot as provided in the original resin service contract. Resin

manufacturing and transportation costs have increased considerably since the original

contract was negotiated in mid 2003. Also the switch to Dow SAR and bicarbonate

conversion added additional cost to the new resin service contract. The new resin service

contract for Dow SAR is $ 103.65 per cubic foot for the resin and an additional $ 5.87 per

cubic foot for the bicarbonate conversion giving a total price under the new contract of

Ace Services Site 4-5 04-1720.01.49LTRA Audi t Report No. 9

IIIIIIIIIIIIIIIIIII

$109.52 per cubic fool. Beds A2 and B2 were the last beds containing the original

Purolite resin at a rate of only $80.70 per cubic foot. All future resin cost calculations

will be based on the higher $109.52 per cubic foot cost under the new supply contract for

bicarbonate converted Dow SAR. It is expected that the Dow resin will show better

treatment performance that the recent batches of Purolite A300. This will be evaluated in

the Tenth audit report.

Ace Services Site 4-6 044720.01.49LTRA Audi t Report No. 9

IIIIIIIIIIIIIIIIIII

Table 4-1

Selected Flow and Chromium Concentration DataAce Services Site

Date

13-Oct-05141516171819202122232425 _|262728293031

Hexavalent ChromiumAt sample location SC-1Hach unit

(ug/L)

000

Totals for Month

ContinentalLabs (ug/L)

185185185185185185185192192192192192192202202202

TRAIN AGallonsTreatedx 1000

634627644618658621630635638655621597611630581563529520483

11495

ChromiumRemoved

(kg)0.4440.4390.4510.4330.4610.4350.4410.4620.4640.4760.4520.4340.4440.4820.4440.4310.0000.0000.0007.194

TRAIN BGallonsTreatedx 1000

632627641619659619632633638653620622609611580562528519482

11486

ChromiumRemoved

(kg)0.4430.4390.4490.4340.4620.4340.4430.4600.4640.4750.4510.4520.443j0.4670.4440.4300.0000.0000.0007.189

RemarksBeds A1 and B1 are lead

Beds A2 and B2 put in lead

New GAC bed on-line

Ace Services SiteLIRA Audit Report #9 4-7 044720.01.49

IIIIIIIIIIIIIIIIIII

Table 4-1Selected Flow and Chromium Concentration Data

Ace Services Site

Date

1-Nov-052345678910111213141516171819202122232425 J2627282930


(ug/L)00

2020264060

130170200200240250

Totals for Month


0

104

269269269269269248248248248248248248248248207


523508492544517511481527510500519499528530469520556526486496480546494524533512486519481574

15391

ChromiumRemoved

(kg)0.0000.0000.0000.0410.0390.0500.0730.1200.2010.2460.3340.3780.4000.4820.4440.5300.5660.5360.4950.5050.4510.5130.4640.4920.5010.4810.4560.4870.4520.450

10.187


522508491544517511481527512500519499529529468512533529513525451548494523533513486519481574

15391

ChromiumRemoved

(kg)0.0000.0000.0000.0410.0390.0500.0730.1200.2020.246

I 0.3340.3780.4010.4810.4430.5220.5430.5390.5230.5350.4240.5150.4640.4910.5010.4820.4560.4870.4520.450

10.190

Remarks

Ace Services SiteLIRA Audn Report #9 4-8 04-1720 01 -19

IIIIIIIIIIIIIIIIIII


Ace Services Site

Date

1-Dec-052345678910111213141516171819202122232425262728293031


(ug/L)

00000

20

100120140160180180

Totals for Month


207207207207207207200

59

197197197197197197197195195195195


477513509516501507430453523509516475534517476531493526508495526516540509509506468530502528504

15647

ChromiumRemoved

(kg)0.3740.4020.3990.4040.3930.3970.3260.0000.0000.0000.0000.0000.0400.1160.1800.2410.2610.3190.3460.3370.3920.3850.4030.3800.3800.3770.3490.3910.3710.3900.3728.727


476513505514507507418438550508515478534516476532495528506494524462540509509523468549516529505

15644

ChromiumRemoved

(kg)0.3730.4020.3960.4030.3970.3970.3170.0000.0000.0000.0000.0000.0400.1150.1800.2420.2620.3200.3450.3370.3910.3450.4030.3800.3800.3900.3490.4050.3810.3910.3738.715

Remarks

New GAC bed on-line

Beds A3 and B3 put in lead

Ace Services SueLIRA Aud i t Report »9 4-9 044720 O I A 9


Ace Services Site

Date

1-Jan-06234567891011


(ug/L)

Totals for Month


195195195185185185185185185185174


492512510510510519516504528461520

5582

ChromiumRemoved

(kg)0.3630.3780.3770.3570.3570.3640.3620.3530.3700.3230.3433.946


492514510508509520515504529465519

5585

ChromiumRemoved

(kg)0.3630.3800.3770.3560.3570.3640.3610.3530.3710.3260.3423.949

Remarks

Ace Services SiteLIRA A u d i t Repon #9 4-10 0-1 -1720.01. -49

Figure 4-1Gallons treated vs chromium concentration

H-VJ

QC

^-x ^^

c 30*r OUO— ?*>•= ^3C on*— ' /lUw ^cc 15 -o^ 10 -

o

0

c

» 0

0 %'*(

0 *

o* 0 0

,# •• • - •

. 0 0

.6

) 200 400 600 800 1000 1200

Chromium (ug/L)

Page 4-11

II

5.0 Action Summary

The following is a list of recommended actions or changes to improve system

• operation or record keeping procedures based on observations made during the ninth

audit. This is a summary list. This list also includes any needed equipment repairs or

• adjustments identified during this audit. Further details can be found in the body of this

audit report. It is noted that only action item 2 is carried over from the eighth audit

I report.

• 1. Insulate the new conduit with the chlorine line between the chlorine shed and

the GWTP.

I2. Install the new conductivity probes on both trains and recalibrate the meters.

I3. Repair or replace (he flow meter at well EX-3d.

I4. Regularly (suggest weekly) go to each well house and manually cycle the

I motor operated flow control valve through full range to keep them from

seizing in place.

I5. Repair or replace the How controller at well EX-4i.

I6. Replace the PVC air vent piping on each of the ion exchange vessels with

• galvanized steel piping.

I

I

I

Ace Services Site 5-1 044720.01.49LTRA Audit Report No. 9

I

BLACK & VEATCHBLACK & VEATCH 6601 College Blvd. Overland Pa*, KS 66211 Tel: (913) 458-2900 USEPA...

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