Simulation of the interaction of water (orange) and oil (blue) when a vertical

boundary is suddenly removed. Shear along the fluid interface creates vortices

that cause mixing. Modeled during EEES 817: Applied Process Simulation.

21st Annual David S. Snipes/Clemson

Hydrogeology Symposium

April 4, 2013

Contest Announcement

What exotic location can you be photographed with your Clemson Hydrogeology hat?

While your colleagues may think that Due West or Nine Times are exotic locations, you know better. Next time you find yourself deep in some far flung exotic terrane with your hat on and a camera ready, don’t hold back. Send your 2013 photo(s) by Jan 1, 2014.

Cecil Huey, Professor Emeritus of Mechanical Engineering and long term attendee of the Symposium, kicking back at the Taj Mahal in Agra, Uttar Pradesh, India in the Fall of 2012

Time BellSouth Auditorium Meeting Rooms 1/2 Meeting Rooms 3/4

7:30 Registration

CO2 Sequestration

Moderator: Ron Falta Soil Gas and Vapor Extraction

Moderator: Gary Birk Geochemistry and Watersheds

Moderator: Aaron Peacock

8:30

Migration of Exsolved CO2 Follow-ing Depressurization of Saturated Brines Falta, Ronald

Vapor Intrusion Mitigation by Sus-tainable Soil Vapor Extraction Birk, Gary

Removing the Ambiguity of Geochemi-cal Analyses in Groundwater using En-vironmental Molecular Diagnostics Peacock, Aaron

8:50

Hysteretic Trapping and Relative Permeability of CO2 in Sandstone at Reservoir Conditions Ruprecht, Catherine

Case Study: PCE Vapor Intrusion Assessment and Mitigation – Former Manufacturing Site – Eastern North Carolina Hollifield, Ed

Representative Pharmaceuticals and Pesticides in Small SC Streams: A Catchment Based Approach to Identify Potential Impacts and Sources Jones, Alan

9:10

Forward and Inverse Modeling of WellBore Deformation During CO2 Sequestration Kim, Sihyun

Advanced Passive Soil Gas Sampling – Collection of High Resolution Data to Effectively Guide Remediation Strategies O’Neill, Harry

Modeling the Effects of Residential Construction Activities on Stream Flow and Sediment Yield Santikari, Vijay

9:30

Remediation using ZVI Moderator: Bob Kelley

Trenches, Wells, and Pumps Moderator: Andrew Alexander

Geophysics and Plumes Moderator: Steven Moysey

9:50

Biological and Chemical Reduction of Chlorinated Solvents by Pneu-matic Fracturing and Injection of Zero-Valent Iron in Saprolite Moskal, Eric

Design and Operation of a Free-Product Gasoline Interceptor Trench in High Relief Terrain with Shallow Bedrock Alexander, Andrew

Geophysical Borehole Logging in Frac-tured Rock for Hydrogeological Appli-cations Bergstrom, Jorgen

10:10

Biological and Chemical Reduction of Chlorinated Solvents by Com-bining Zero-Valent Iron and Emul-sified Vegetable Oil Liskowitz, Mike

Extraction Well Design, Process Steps and Practical Considerations Albenesius, Phillip

Time-lapse 3D Imaging of a Lab Scale Forced Infiltration Experiment Mangel, Adam

10:30 Chemical and Biological Reduction in Vadose Zone Sediments Rossabi, Joseph

A Comparison between Pumps and the Hydrasleeve© Sampling Methods at the Savannah River Site, South Carolina Craig, Robert

Improved Solute Concentration Estima-tion using a Pattern Matching Approach to Capture Site-specific Plume Mor-phologies Oware, Erasmus

10:50 Please move to the Main Ballroom

11:10 Keynote Talk: Computer Modeling In Hydrogeology: Where Did It Come From, How Has It Evolved, And Where Is It Going? Fred Molz, Clemson University

12:00 Lunch

Break

SpeakerScheduleApril4,2013

Time BellSouth Auditorium Meeting Rooms 1/2 Meeting Rooms 3/4

Constructed Wetland Treatment Systems

Moderator: Jim Castle and John Rodgers

Fractures Moderator: Bill Slack

Remediation Moderator: Pat Hicks

1:00

Fate and Distribution of Arsenic in a Pilot-Scale Constructed Wetland Treatment System for Simulated Bangladesh Groundwater Schwindaman, Jeff

Distributions of Fracture Form Sug-gested By Tiltmeter Data Slack, William

Oxidation or Reduction – Not Mutually Exclusive Options Hicks, Patrick

1:20

Treatment of Selenium as a Constitu-ent of Ecological Concern in Energy-Produced Waters Huddleston, Matt

Influence of High Permeability Prop-pant-Filled Hydraulic Fractures on Ambient Groundwater Flow Fields and Resulting Benefits for Passive Remediation Hall, Richard

Case Study: Full Scale Treatment of a TCE Groundwater Plume Using ISCO at an Active Manufacturing Facility in Spartanburg, South Carolina Hollifield, Ed

1:40

Seasonal Performance of a Hybrid Pilot-Scale Constructed Wetland Treatment System for Simulated Fresh Oilfield Produced Water Alley, Bethany

Ambient Deformation of Permeable Fractures Hisz, Dave

Pilot Study for In-Situ Thermal Reme-diation of Chlorobenzenes: Substantia-tion and data acquisition goals for the design of a full scale thermal remedia-tion. Bostian, Susan

2:00

Effects of Evapotranspiration on Wa-ter Treatment Performance in Con-structed Wetlands Beebe, Alex

Numerical Modeling of the Former Homestake Gold Mine: A Study of the Hydrologic and Mechanical Ef-fects of Deep Rock Excavations on Fractured Rock Masses Ebenhack, Johnathan

Outlining the Advantages of Selecting Catalyzed Hydrogen Peroxide or Acti-vated Sodium Persulfate at Two Differ-ent Petroleum Hydrocarbon Sites Moody, Will

2:20

A Demonstration Constructed Wet-land Treatment System for Unconven-tional Gas Produced Water Coffey, Ruthanne

Quantifying Radial Borehole Defor-mation During Well Tests Baldwin, Jonathan

Introduction to Cometabolic Bioreme-diation Alden, David

2:40 Break

Remediation

Moderator: Rob Workman Legal Issues and Standards Moderator: Charles Ormond

Chemistry and Physics at Solid:Water Interfaces Moderator: Brian Powell

3:00

Solvent DNAPL to MCL: Are We There Yet? Workman, Robert

Legal Issues for the Professional Sci-entist Ormond, Charles

Intermediate Scale Transport of Nanoparticles in the Vadose Zone Emerson, Hilary

3:20

System Design Enhancements of a Dual-phase Extraction System for the Cleanup of Heavy Fuel Oils Montoy, Jorge

Rail to Rail – A Brownfields Agree-ment Based on Nothing Harriger, Joselyn

An Examination of Plutonium Re-dox Chemistry on the Surfaces of Hematite, Silica, and Montmorillo-nite using XANES Estes, Shanna

3:40

Ozone Sparging as a Soil/Groundwater Remediation Strategy at Large Scale Sites Wheeler, Kevin

Measuring Analytical Laboratory Performance: Establishing Basic Data Review standards Rosseter, Diane

Electrical Response of Grain Sur-face Ion Adsorption Processes Ob-served by Spectral Induced Polari-zation Measurements Hao, Na

Time BellSouth Auditorium Meeting Rooms 1/2 Meeting Rooms 3/4

4:00 Break

Decision Making

Moderator: Matt Huddleston Creative Inquiry

Moderator: Larry Murdoch Creative Inquiry

Moderator: Scott Brame

5:15 Mixer at Geology Museum

4:10

Investigation of the Changes in Uranium, Selenium, and Radium Speciation and Mineralogy that Occur During Uranium In-Situ Recovery Operations Hixon, Amy

Sediment Transport after Dam Removal on Twelve-Mile Creek, Norris, SC Waterhouse, Tyler

Using Soil pH and Ca/Mg Hardness to Map Bedrock in the Clemson Ex-perimental Forest Wylie, Peter

4:30

Seeing Green by Going Green: Maximizing Ecosystem/Community Services Benefits through Strategic Green Stormwater Infrastructure Design Artita, Kimberly

Modeling Sediment Transport associated with a Reservoir Sedi-ment Release following Dam Re-moval on Twelve-mile Creek, SC Chamlee, William

Geologic Mapping by Soil Analysis: Determining the Contact between Amphibolite and Biotite Gneiss us-ing Soil Chemistry and pH Black, Erin

4:50

Naranpur Express: Understand-ing Environmental Decision-Making Processes through Seri-ous Game Development Hanna, Alex

Characterizing Water Content Trends Observed in Local Sapro-lite Soils Lyles, Molly

Mapping of the Clemson Forest us-ing Digital Field Mapping Tech-niques Lefitz, Alex

Workshops 8:30 - 10:50 AM: "When this geologist speaks, people listen": A short course on presentation skills for Geologists Dr. David Pelton 1:00—5:00 PM 3D Imaging of the Subsurface with Multi-channel Ground Penetrating Radar: From Promise to Practice Dr. Stephen Moysey

Posters Spatial Analysis of Well Yields in Fractured Bedrock Terrains of the Piedmont of Northwestern SC Bailey, Brooks The Effectiveness of Rain Gardens at Mitigating Nitrogen Runoff to a Piedmont Lake, Greenville, SC Bressler, Alison Heterogeneity of groundwater- stream water interactions in a headwaters Southern Appalachian watershed, Cullowhee, North Carolina Ferri, Kelly Union High School Gun Range Soil testing, Delineation, and Treatment Lauber, Kenneth

1

Abstracts (Ordered by last name of first author)

Extraction Well Design, Process Steps and Practical Considerations Albenesius, Phillip, albenesiusp@ saic.com, Science Applications Internation-al Corporation (SAIC) Energy, Environ-ment & Infrastructure, Aiken, SC Groundwater extraction well design is an endeavor influenced by a number of varia-bles that might include depth to groundwa-ter, grain size distribution in the targeted zone, tidal influence, non-aqueous phase liquid (NAPL) recovery objectives, desired radius of influence, casing storage, and well construction materials. Optimal well efficiency is a common goal in any well design. This presentation attempts to lay out the ideal process steps tempered by some practical, real-world considerations. When NAPL recovery is a primary objec-tive, the process begins with effective site characterization and development of a ro-bust conceptual site model that includes accurate smear zone delineation. Out of that critically important initial step comes selection of the target screen zone and eval-uation of the grain size distribution across the screen zone. Those tasks are followed by the filter pack design, selection of the screen slot size, and selection of the casing diameter. Now come the practical consid-erations as the drilling bid specification is written, drilling bids are solicited, a drilling subcontractor is selected, and the drilling and well installation are executed. The process is made whole with effective well development, step drawdown testing, pump selection and installation, and well head completion. Aggressive well design can

be a daunting endeavor, especially during the development phase when the filter pack gradation occurs and the volume of pumped sand diminishes to zero. Through-out the process, stay true to the objectives and trust your science. Introduction to Cometabolic Bioremediation Alden, David, david.alden@ tersusenv.com, and Gary M. Birk, Tersus Environmental, Wake Forest, NC An emerging groundwater remediation practice area to address large dilute groundwater impacts is cometabolic biore-mediation. Cometabolism is the simultane-ous degradation of two compounds, in which the degradation of the second com-pound (the secondary substrate) depends on the presence of the first compound (the primary substrate). This bioremediation strategy has been successfully used on some of the most recalcitrant contaminants, e.g., trichloroethene, dichloroethene, vinyl chloride, 1,4-dioxane.

In aerobic cometabolic bioremediation indigenous bacteria are stimulated by add-ing oxygen and a cometabolic growth sub-strate to trigger the production of enzymes. These enzymes then oxidize or degrade the target pollutant via cometabolism. Alkane gases such as methane, propane or ethane are commonly used as the primary sub-strate. Indigenous mircroorganisms while oxidizing the primary substrate for energy and growth express a monooxygenase en-zyme that fortuitously degrades the con-taminant (the secondary substrate). The

2

enzyme is a protein-like substance that acts as a catalyst for degradation of the contam-inant. Contaminant degradation provides no apparent benefit to the microorganism involved. The biodegrader is not dependent on the contaminant for carbon or energy therefore can perform at low levels of con-tamination as in the case of meeting vinyl chloride groundwater standards.

This method is most useful for biore-mediation of pollutants that are not them-selves good aerobic growth substrates for bacteria. Bioremediation strategies that em-ploy cometabolism have the advantage of being able to degrade contaminants to trace concentrations, very low parts per billion levels and actually to parts per trillion. This presentation will discuss the importance of cometabolism in the biodegradation of con-taminants in the environment. Results and lessons learned from field demonstrations will also be presented.

Design and Operation of a Free-Product Gasoline Interceptor Trench in High Relief Terrain with Shallow Bedrock Alexander, Andrew W., andy@ blecorp.com, Trevor J. Benton, and Ben-jamin P. Nisbeth, Bunnell-Lammons En-gineering, Greenville, SC Releases of gasoline impacted soil and groundwater at a multi-discipline construc-tion services facility located in the Blue Ridge physiographic province of North Carolina. Free-product gasoline migrated from the release point and discharged into local surface water (creek). The discharge area is located at the terminus of a steep slope. Difficult access and shallow bed-rock conditions in the discharge area lim-ited product recovery options. A variety of

remedial measures were employed to ad-dress free phase gasoline in soil and groundwater. A free-product interceptor trench was designed and installed and sev-eral product recovery methods were devel-oped to meet project objectives.

The subject facility includes a vehicle fueling operation with one above ground diesel and one above ground gasoline stor-age tank with a single dispenser pump for each fuel type. The property slopes from the fueling area near the southern property boundary to a creek on the northern proper-ty boundary approximately 335 feet from the release point. There is approximately 90 feet of relief from the release point to the discharge area.

A discharge of gasoline in the creek was discovered in 2007. An emergency response action was performed by deploy-ing oil adsorbent booms at the point of dis-charge and further downstream. A small exploratory trench near the creek was exca-vated and gasoline was observed in the trench’s shallow groundwater. Further in-vestigation revealed that a flexible hose coupling at the gasoline dispenser pump had failed resulting in the release of an un-known quality of gasoline.

A soil assessment in the release area was conducted in 2007 and 2008. The lim-its of contaminated soil were defined and a mobile source remediation unit (soil vapor extraction [SVE] system) was deployed in 2008 as an interim remedial action.

Seventeen groundwater monitoring wells were installed from 2007 through 2009 to establish the horizontal limits of the free-product and dissolved phase gaso-line. Additionally, surface water sampling was conducted as part of the assessment. The limits of the groundwater and surface water impacts were substantially defined. The free-product appeared to migrate on top of and into the bedrock surface until

3

discharging out of the bedrock and through soil at the creek boundary.

Free-product gasoline removal was ini-tiated in 2008 utilizing passive downhole skimmers and aggressive fluid vapor re-covery (AFVR) in several affected wells.

A free-product interceptor trench was designed and subsequently installed in ear-ly 2009 near the creek. The trench was in-stalled to the top of bedrock (approximately 10 feet below ground sur-face) and constructed with appropriate fil-ter media, bentonite cap, and extraction piping. Product gauging was conducted until sufficient product had accumulated to initiate recovery. A liquid thickness (product and groundwater) of approximate-ly 3 feet was observed in the trench. Dense woods, steep topography, and limited re-sources were available to facilitate product recovery. A pilot recovery program was employed utilizing purging methods ade-quate for the product accumulation rates observed. A manually operated vacuum skimming system was designed and imple-mented as the final option which provided effective recovery. As of mid 2012, a ma-jority of the available product was recov-ered and supplemental soil vapor extraction began in the trench area.

Seasonal Performance of a Hybrid Pilot-Scale Constructed Wetland Treatment System for Simulated Fresh Oilfield Produced Water Alley, Bethany L., clemsonwfbphd@ aol.com, and John H. Rodgers, Jr., School of Agricultural, Forest, and Envi-ronmental Sciences, Clemson University, Clemson, SC; and James W. Castle, De-partment of Environmental Engineering and Earth Sciences, Clemson University, Clemson, SC

The purpose of this research was to meas-ure seasonal differences in performance of a hybrid pilot-scale free water surface con-structed wetland treatment system (CWTS) for renovating simulated fresh oilfield pro-duced water (FOPW) for surface water dis-charge and irrigation. Seasonal changes (e.g. temperature, photoperiod, microbial activity) can affect treatment performance of the CWTS for constituents (oil, Cd, Cu, Ni, and Zn). The system was designed to treat simulated FOPW containing elevated concentrations of constituents (i.e. 6 mg Cd+2/L, 4 mg Cu+2/L, 6 mg Ni+2/L, 6 mg Zn+2/L, and 100 mg Rotella® T 15W40/L). The hybrid CWTS was constructed out-doors and consisted of an oil/water separa-tor and two wetland series with four cells each. Samples from inflow and outflows of the CWTS were analyzed for oil marker compounds using gas chromatography and for Cd, Cu, Ni, and Zn using inductively coupled plasma-optical emission spectros-copy. Water temperatures ranged from 0°C to 30.2°C in the wetland cells. There were no measurable seasonal differences in treat-ment performance (i.e. removal rates, ex-tents, and efficiencies) likely due to the de-sign of the hybrid system and conditions established in the wetland cells for removal processes. From inflow to outflow, the CWTS decreased oil marker compound concentrations by ≥ 99% and Cd, Cu, Ni, and Zn concentrations by ≥ 98%. The oil/water separator (~66% oil removal) and wetland cells (~97% Cd, Cu, Ni, and Zn removal) contributed to year-long sustained performance of the hybrid CWTS. Results from this seasonal performance study pro-vided evidence that the hybrid CWTS can achieve irrigation and surface water dis-charge criteria for simulated FOPW con-taining elevated concentrations of oil and metals.

4

Seeing Green by Going Green: Maximizing Ecosystem/Community Services Benefits through Strategic Green Storm-water Infrastructure Design Artita, K.S., Kimberly.artita@cardno.com, Cardno ENTRIX, Clemson, SC Combined sewer overflow (CSO) control in ageing urban areas is a costly and on-going issue. In addition, urban municipali-ties must deal with other daunting issues such as economics, sustainability, etc. Us-ing a case study in the City of Philadelphia, I will discuss how decision makers can in-corporate the concept of natural capital or ecosystem services, in sewershed-scale green storm-water infrastructure (GSI) de-signs aimed at reducing CSO volumes. Tri-ple bottom line estimates of benefits from the City’s long-term control plan update, Green City, Clean Waters, and continuous hydrologic/hydraulic simulations using EPA’s Storm Water Management Model were coupled with a simple genetic algo-rithm. This study indicates that GSI strate-gically distributed across a sewershed can come close to meeting established state and federal CSO volume reduction and water quality requirements, and at the same time yield positive net economic benefits for the City of Philadelphia, minimizing the cost-benefit ratio. Quantifying Radial Borehole De-formation During Well Tests Baldwin, Jonathan A., baldwi5 @clemson.edu, and Lawrence Murdoch, Environmental Engineering and Earth Sci-ences, Clemson University, Clemson, SC The objective of this project is to quantify

the radial deformation of a well bore at shallow depths when the well is pumped at a constant rate. Pumping creates a pressure differential between the interior and exteri-or of the casing, potentially causing the casing to deform in a radial direction. The pressure differential will depend on the permeability of the formation and grout seal, so this test could be used as a diagnos-tic for a leak along the outside of a well casing. Furthermore, radial deformation measurements made within an open bore in rock could be used to characterize the elas-tic modulus of the rock.

A device called a RAD-X (Radial Ex-tensometer) was designed to monitor the radial deformation of a casing. This device extends against the opposing sides of the well, and compresses or expands according to the deformation of the casing. Minute changes in how far the RAD-X must ex-tend are quantified using a Fiber-Bragg Grating strain sensor. This sensor is con-nected to an optical sensing interrogator, which sends a pulse of light down the fiber optic cable that runs through the strain sen-sor. The interrogator then records the change in wavelength that results from the stretching of the fiber optic sensor. This wavelength data is then translated into a measurement of amount of strain experi-enced by the strain sensor.

A proof-of-concept test was conducted by putting the RAD-X into a well casing at depth of 65 ft. A packer was placed below the RAD-X in the casing, and water was pumped from the casing at a constant rate to decrease the head in the well by 10ft. The well was then allowed to recover, and the process was repeated. During this test, changes in the head, water pressure, tem-perature, and radial deformation were mon-itored as a function of time.

5

Spatial Analysis of Well Yields in Fractured Bedrock Terrains of the Piedmont of Northwestern South Carolina Bailey, Brooks J., Weston R. Dripps, and Suresh Muthukrishnan, Earth and Envi-ronmental Sciences, Furman University, Greenville, SC Fractured bedrock aquifers are structurally complex groundwater systems. Groundwa-ter flow is limited to secondary porosity features such as faults and fractures on ac-count of the low primary porosity and per-meability of the native bedrock. The hydro-logic productivity of wells drilled within these systems is spatially and vertically variable due to the limited interconnectivi-ty among these features. The purpose of this study was to identify the structural and lithological controls on well productivity within the fractured bedrock aquifer of the Piedmont of northwestern South Carolina. Groundwater well data (e.g., well depth, well yields, static water level) of 1,070 wells, geologic data (e.g., lithology, mapped structural features), and topo-graphic data (e.g., surface elevation, slope) were integrated within a GIS database for a spatial analysis of well yield distribution. Borehole geophysical logs of 7 selected wells were also analyzed for a better verti-cal understanding of the depth and extent of fracture zones. Wells dug in alluvium had the highest median yield (15 gal/min), while those dug in schist, amphibolite, and gneisses had lower median yields (9, 8.5, and 8 gal/min, respectively). Surprisingly, non-parametric statistical analyses indicat-ed that no geologic or topographic varia-bles considered were strongly correlated with reported well yields. Spearman’s coef-ficients for well depth (0.24), static water

level (0.19), proximity to waterbodies (-0.10), and proximity to lithologic contacts (-0.08) were statistically significant, but only moderately to weakly correlated with well yield. Topographic variables and proximity to mapped faults were not statis-tically significant. Interpretation of geo-physical logs indicated that high-yielding wells had increased fracturing at depths greater than 150 feet below the land sur-face. Wells dug in alluvium had the highest yields due to the higher porosity and per-meability compared to the bedrock. The lower median yields of other lithologies are attributed to lack of fracture development in amphibolite and low degree of weather-ing within gneiss foliation planes. To max-imize yields, wells should be dug in alluvi-um close to waterbodies and lithologic con-tacts. Wells in other lithologies should be dug greater than 150 feet to reach produc-tive fractures. Effects of Evapotranspiration on Water Treatment Performance in Constructed Wetlands Beebe, Alex, donaldb@g.clemson.edu, and J.W. Castle, Environmental Engineering and Earth Sciences, Clemson University, Clemson, SC; and J.H. Rodgers Jr., School of Agricultural, Forest, and Envi-ronmental Sciences, Clemson University, Clemson, SC Evapotranspiration (ET) may affect treat-ment performance in constructed wetlands by enhancing constituent transport through the hydrosoil where favorable reactions occur and by decreasing hydraulic loading leading to an increase in hydraulic reten-tion time (HRT) and a concentrating effect on constituents. This research aims to de-termine the significance of plant transpira-

6

tion on vertical transport of constituents and to assess the net effects of water loss attributed to ET on constructed wetland performance. Eight vertical tracer tests were performed on bench-scale wetlands with either trimmed or untrimmed broad-leaf cattails to measure transport time of tracer solution from the water surface to a depth of 5 cm. Mean tracer arrival time dif-fered significantly (p = 1.2 x 10-8) between the untrimmed and trimmed bench-scale wetlands (104 minutes versus 450 minutes, respectively) demonstrating that plant tran-spiration contributes significantly to verti-cal flow through hydrosoil. In addition, a flowing wetland lysimeter constructed us-ing 265-L storage containers filled with sand and cattails was used to record ET and determine crop coefficient during summer 2011. Results indicate that ET from the wetland lysimeter was 2.5 times greater than the calculated reference ET (Kc = 2.5; R2 = 0.96). The calculated crop coefficient was used in conjunction with a first-order tank-in-series model to predict removal of both a conservative constituent (k = 0.2 d-1) and readily treatable constituent (k = 1.2 d-

1) in a constructed wetland (30 cm water depth, 4-day HRT, and 100 mg/L constitu-ent loading) operating under a range of po-tential cattail ET rates (0, 10, 20, and 30 mm/d). The model predicts that removal efficiency of the conservative constituent decreases with increasing ET rates (54.1% at 0 mm/d versus 39.0% at 30 mm/d) while removal efficiency of the readily treatable constituent increases with increasing ET rates (98.5% at 0 mm/d versus 99.1% at 30 mm/d). This study confirms that plant tran-spiration enhances transport of constituents through hydrosoil and also indicates that increasing ET rates may enhance removal of readily treatable constituents and de-crease removal of conservative constitu-ents.

Geophysical Borehole Logging in Fractured Rock for Hydrogeologi-cal Applications Bergstrom, Jorgen, Jorgen.Bergstrom @gel.com, GEL Geophysics, Marietta, GA Geophysical borehole logging with acous-tic and optical televiewers as well as with other modern logging tools can be used to determine depth, dip, strike and aperture of fractures and fracture zones in open hole segments of wells drilled into rock. Frac-tures from which there is inflow into or outflow from the well can then be deter-mined by measuring the vertical flow in the well with a heat pulse flowmeter log under low rate pumping and ambient conditions. This information can be used by geohy-drologists to develop more accurate groundwater flow models for a site and de-sign groundwater remediation programs. This presentation will include borehole logging data examples from monitoring wells and water supply wells of different age and configurations and discuss strength and limitations of the different logs. Vapor Intrusion Mitigation by Sus-tainable Soil Vapor Extraction Birk, Gary M., gary.birk@tersusenv.com, Tersus Environmental, Wake Forest, NC; Jymalyn Goodwyn, Mills and Cawood, Montgomery, AL; Glen Vallance, CGRS, Inc., Fort Collins, CO; and Don Ray, Per-formance Technologies, Tallahassee, FL Vapor intrusion is the migration of volatile contaminants from the subsurface into overlying buildings. This often occurs when contaminants from either the soil or groundwater enter the soil gas at the water table or in the vadose (unsaturated) zone.

7

The contaminated soil gas then migrates under or diffuses until they escape into the atmosphere or enter the zone of influence of a building. Remediation of vapor intru-sion impacts are often required if the vapor intrusion pathway is determined to be com-plete at a site and indoor air concentrations of volatile chemicals exceed levels of con-cern.

A growing trend in environmental re-mediation is the use of natural processes. These approaches are reducing the costs of cleanup and intruding less on the environ-ment. Sustainable soil vapor extraction is an enhanced attenuation (EA) approach that removes volatile contaminants from the vadose zone. The MicroBlower Sus-tainable Soil Vapor Extraction System (US Patent No. 6,971,820) developed by the U.S. Department of Energy’s Savannah River National Laboratory is an example of such an approach.

Targeting the “vadose zone” during remediation traditionally has been consid-ered difficult. The MicroBlower™ Soil Vapor Extraction System is a simple, cost-effective device with the potential to play a large role in the arsenal of tools for envi-ronmental remediation activities and is spe-cifically designed for remediation of organ-ic compounds in the vadose zone and re-mediation of vapor intrusion impacts. Mi-croBlower™ uses a small, low power vacu-um blower to extract or inject gases into the subsurface for remediation. Because the components of the system have a long op-erating life, the system is useful for long-term cleanup operations, particularly where mass transfer limits the rate of remediation. MicroBlower™ is effective in targeting small source zones where conventional SVE is too excessive.

While similar in design to an active soil vapor extraction (ASVE) blower, the Mi-croBlower™ is a low-cost alternative de-

signed to run on renewable sources of ener-gy to treat volatile organic compound (VOC) contamination in the unsaturated zone. The system uses a small, low power vacuum blower to extract or inject gases into the subsurface for characterization or remediation. MicroBlowers require only between 20 and 40 watts and can be pow-ered using photovoltaic panels, wind gener-ators, 24-volt battery bank recharged by either photovoltaic panels or wind genera-tors or 24-volt power from a 110 to 24 volt transformer. MicroBlower™ offers the advantage of a reduced carbon footprint and very low operating expenses.

Lessons Learned: MicroBlowers are ideal for remote locations with limited or no ancillary infrastructure. By using re-newable sources of energy, the Mi-croBlower™ eliminates the need for gener-ators and fuel storage at remote locations. The MicroBlower™ design also eliminates ancillary infrastructure that are generally required to run conventional ASVE sys-tems in remote areas. MicroBlowers offer the advantage of a reduced carbon footprint and very low operating and maintenance expenses.

Geologic Mapping by Soil Analy-sis: Determining the Contact be-tween Amphibolite and Biotite Gneiss using Soil Chemistry and pH Black, Erin, emblack@g.clemson.edu, and Scott Brame, Environmental Engineering and Earth Sciences, Clemson University, Clemson, SC Soil chemistry was used to determine the spatial distribution of bedrock at a site in the northern portion of the Clemson Exper-imental Forest. The goal was to differenti-

8

ate the contact between a relatively pure outcrop of amphibolite (99% hornblende) and the predominant biotite gneiss that sur-rounds the amphibolite on three sides. The close proximity (~100 feet) of the gneiss outcrops reduced the uncertainty involved in mapping the contact. This study extends the research done in 2012 by Clemson un-dergrad Alex Grayson. Alex investigated the potential of mapping the contact based on soil pH values of the A and B soil hori-zons using an inexpensive color-based soil pH kit. While it is known that the pH of soils produced by the weathering of biotite gneiss tend to be more acidic than the soils produced by the weathering of amphibo-lite, Alex’s field pH values were not vali-dated by soil chemistry and lab pH tests.

Chemical analysis of the soil samples were conducted by the Clemson Agricul-tural Services Laboratory (CASL). This lab determines the concentration of major cations (P, K, Ca, Mg, Na, Zn, Mn, Cu, B) using a Mehlich 1 soil extraction (0.05N HCl + 0.025N H2S04) and an Inductively Coupled Plasma Atomic Emission Spec-trometer (ICP-AES). Soil pH is measured using an AS-3000 Dual pH Analyser.

After obtaining the results from the lab, the soil chemistry data was associated with the respective sample locations using GIS. The pH and cation concentrations were in-terpolated using the Inverse Distance Weighted and Kriging techniques. Magne-sium and Calcium concentration positively correlated with the location of the amphib-olite outcrops and allowed for the determi-nation of the contact with a good measure of certainty. The other cations were less promising in this respect. The laboratory pH results showed a much stronger associ-ation with the known outcrops than the field pH test results.

The quality of the CASL measurements was assessed for precision and accuracy.

Precision was measured by sending dupli-cate soil samples to CASL to determine the variability in their technique. Accuracy is currently being assessed through replica-tion of CASL procedures. Pilot Study for In-Situ Thermal Remediation of Chlorobenzenes: Substantiation and Data Acquisi-tion Goals for the Design of a Full Scale Thermal Remediation Geckeler, Grant, grant.geckeler @tpstech.com, TPS Tech America, Los Angeles, CA; and Susan Bostian, susan @innoveatech.com, Innovea Technologies, Holly Spring, NC  A chemical manufacturing facility in France was closed in 2007. It had manu-factured various solvents, feedstocks, fuel additives and herbicides since 1954. An underground pipeline rupture was identi-fied as the source of Chlorobenzene im-pacts in 2009. NAPL levels of Chloroben-zene, 1,2-Dichlorobenzene, 1,4-Dichlorobenzene and 1,2,4-Trichlorobenzene were identified across a 60,000 sq. ft. area adjacent to the chemical facility and rail yard.

An in-situ thermal desorption pilot study was designed for two goals: (1) sub-stantiate that the desired treatment tempera-ture and specifications could be attained; and (2) obtain temperature, pressure, off-gas, kinetics, and related treatability data for the optimization of the full scale design. The design, operations and results of the pilot study will be discussed. The data from the pilot study and the impact of that data on the final full scale design will be pre-sented.

9

The Effectiveness of Rain Gardens at Mitigating Nitrogen Runoff to a Piedmont Lake, Greenville, South Carolina Bressler, Alison S., alison.bressler@ furman.edu, Weston R. Dripps, and C. Brannon Andersen, Earth and Environ-mental Sciences, Furman University, Greenville, SC Urbanization alters the flow and chemistry of surface water systems. The addition of impervious cover increases runoff and de-grades water quality. Rain gardens have become a popular Low Impact Develop-ment (LID) strategy to help mitigate the impacts of urban runoff by reducing runoff, capturing heavy metals and hydrocarbons, and diminishing nutrient and sediment loads to receiving surface water systems. The success and effectiveness of a rain gar-den is dictated by its design (i.e., size, fill media, vegetation type and density, and underlying geology) and the region’s storm characteristics (i.e., rainfall patterns, fre-quency, and intensity). This study looked at the effectiveness of four rain gardens on Furman University’s campus in Greenville, South Carolina at minimizing nitrogen loading to Furman Lake. The rain gardens were installed in 2008 as part on an ongo-ing lake restoration project aimed at im-proving the lake’s degrading water quality. Inflow and outflow water samples were collected at each garden for six major storm events from June – July 2012. Roof, parking lot, and lawn runoff and precipita-tion samples were also collected for each storm event from sites within the lake’s watershed. Dry atmospheric deposition was identified as the primary source of nitrogen loading to the lake, with loading rates seemingly governed by the duration of dry

periods between rain events. Overall in the gardens, nitrate levels were effectively re-duced from inflow median concentrations of 3.517 mg/L to outflow median concen-trations of 0.0534 mg/L for the six storm events, although the efficiency varied among gardens. The two rain gardens with the deeper, wider infiltration zones and denser vegetation were markedly more ef-fective at reducing nitrate loading to the lake compared to the other two gardens which were only marginally effective. The results highlight the importance of proper and appropriate garden design and size to ensure successful water quality improve-ment.

Modeling Sediment Transport as-sociated with a Reservoir Sediment Release following Dam Removal on Twelve-mile Creek, SC Chamlee, William, wchamle@ clemson.edu, and Larry Murdoch, Envi-ronmental Engineering and Earth Sciences, Clemson University, Clemson, SC The Woodside I and Woodside II dams were removed from Twelve-Mile Creek in 2011 as part of a natural attenuation plan to remediate PCB contamination in Lake Hartwell. The concept behind the plan is that removing the dams will increase sedi-ment flux, which will cover and isolate PCB-laden lake sediments. Considerable sediment existed in the region behind the dams when the dams were removed, so a field study of the transport of that sediment was initiated to evaluate how it fits into the remedial plan. The field study consists of surveys of streambed topography to evalu-ate erosion and deposition at select loca-tions. The field data shows that the sedi-

10

ment that originated behind the dam was mobilized and accumulated in the reach below the dam. The factors affecting the transport of the sediment are unclear, how-ever. The purpose of this project is to eval-uate factors affecting sediment transport in a computer model in order to gain insight into processes occurring in the field. The one-dimensional hydrodynamic modeling software Mike 11 (Danish Hydrologic In-stitute) was selected for modeling the sedi-ment transport and deposition. In an effort to confirm the capability of analyzing sedi-ment input and transportation, a prelimi-nary simulation of the removal of sediment was created using idealized conditions. The preliminary analysis confirms the ability of the code to simulate the movement of a sudden influx of sediment, as would have occurred when the Woodside dams were removed. The preliminary analysis is be-ing extended to include temporal discharge, channel geometry, sediment grain size, and other site characteristics. A Demonstration Constructed Wetland Treatment System for Un-conventional Gas Produced Water Coffey, Ruthanne E., ruthanne.coffey@ gmail.com, and J.W. Castle, Environmen-tal Engineering and Earth Sciences, Clem-son University, Clemson, SC; and J.H. Rodgers Jr., School of Agricultural, For-est, and Environmental Sciences, Clemson University, Clemson, SC Unconventional gas produced water (PW) can potentially be treated using constructed wetland treatment systems (CWTSs). The objectives of this investigation were to (1) characterize PW from coal bed methane (CBM), a type of unconventional gas, at a

producing field in the Black Warrior Basin of Alabama, and identify constituents of concern (COCs); (2) design and construct an on-site demonstration CWTS to reduce concentrations of the COCs identified; (3) assess treatment performance by calculat-ing removal extents, efficiencies, and rates; and (4) compare performance of two or-ganic carbon amendments (AquaSmartTM and mulch). The design enables treatment of ammonia, Ba, Cd, Fe, and Mn by target-ing specific biogeochemical pathways. These treatment pathways include nitrifica-tion and denitrification of ammonia to ni-trogen gas, precipitation of Ba in the pres-ence of sulfate, precipitation of Cd through dissimilatory sulfate reduction, and oxida-tion and sorption of Fe and Mn. COC con-centrations in inflows and outflows were measured bimonthly for 6 months. Initial analyses of PW samples indicated inflow concentrations of 0.1-3.3mg ammonia-N/L, 6.0-28mg Ba/L, 0.0001-0.0002 mg Cd/L, 0.06-2.5mg Fe/L, and 0.02-1.7mg Mn/L. Ammonia-N, Ba, Cd, Fe, and Mn concen-trations decreased to less than current water quality criteria from the Clean Water Act (1.4 mg ammonia-N/L, 1.0mg Ba/L, 0.000025mg Cd/L, 1.0mg Fe/L, and 0.05mg Mn/L). Even though inflow con-centrations of COCs varied by orders of magnitude, the demonstration system suc-cessfully achieved consistent removal. Re-sults indicate that the robust design of the demonstration CWTS can reduce concen-trations of COCs as mass loadings change over time. COCs in this study occur in PWs associated with other types of uncon-ventional gas making this treatment design applicable to many gas fields.

11

A Comparison between Pumps and the Hydrasleeve© Sampling Meth-ods at the Savannah River Site, SC Craig, Robert R., bob.craig@srs.gov, SRNS, Aiken, SC Groundwater monitoring well sampling methods most commonly used at the Sa-vannah River Site are variable speed pumps, bladder pumps, Hydrasleeve©, Westbay™ probe system and bailers. Since 2007 the instantaneous grab bag sample method, Hydrasleeve©, is the pre-ferred method for wells with small sample volume bottle kits. Hydrasleeve© is pre-ferred when monitoring for Volatiles, Met-als and/or Tritium. To date, there are ap-proximately 228 wells using the Hy-drasleeve© sampling method, of which on-ly 61 were deployed to new wells. Data from sampling before and after Hy-drasleeve© deployment for monitoring constituents Tetrachloroethylene (PCE), Trichloroethylene (TCE), Aluminum, Bari-um, Lead, Nickel, Sodium and Tritium as well as field parameters pH, Turbidity and specific conductivity are presented. Numerical Modeling of the Former Homestake Gold Mine: A Study of the Hydrologic and Mechanical Ef-fects of Deep Rock Excavations on Fractured Rock Masses Ebenhack, Johnathan, and Larry Mur-doch, Environmental Engineering and Earth Sciences, Clemson University, Clem-son, SC The former Homestake gold mine near Lead, South Dakota, has workings that ex-tend over roughly 6 km3 and to a depth of

2.4 km, and this setting provides an excel-lent opportunity to advance understanding of hydrogeologic and geomechanical pro-cesses associated with large excavations in fractured and faulted rock masses. The mine workings follow three primary ore bodies along parallel trends that extended over nearly 5 km and plunges at roughly 40° to approximately 2.4 km depth. The ore is hosted in highly deformed, Protero-zoic metamorphic rocks with a regional layering that strikes N20W and dips rough-ly 60NE. At least one known fault is roughly parallel to regional layering and intersects the westernmost of the three main ore bodies. To understand how the development of the mine affected the sur-rounding hydrology and stress-strain state of the rock around the mine a 3-D finite element, poroelastic model was developed. This model was used to develop a better understand of how mining operations have altered the local hydrology and stress-strain state around and in the mine region. The mine workings were represented as discrete dual porosity and permeability domains with two domains, one representing the mined out workings and one representing the original competent host rock, which occupy the same volume. To simulate mining the domain representing the mined out workings progressed in depth with time. Constitutive properties of the model assumed a fractured medium represented as an effective continuum with fracture aper-tures and compliance as adjustable parame-ters. Anisotropic conditions for hydraulic conductivity, K, Young’s modulus, E, and shear modulus, G, were included in the analysis. A 1:5 ratio of K parallel and nor-mal to layering was used based on studies elsewhere in the Black Hills. Anisotropic conditions for the elastic parameters E and G were taken from laboratory measure-ments with principle components parallel

12

to strike and dip and normal to layering (Pariseau et al. 1984). Hydraulic calibra-tion of the model involved adjusting the initial and minimal fracture apertures, δo and δmin, and fracture stiffness, Cni, until model predictions matched available de-watering data. Mechanical calibration was done by varying the density of the rock, ρrock, Poisson’s ratio, ν, and the ratio be-tween the moduli of the ore bodies and rock, Eore/Eb, as well as by adding in initial stresses until the difference between the predicted stresses and the measured in-situ stresses was minimized.

Calibration of the model gave estimates for the parameters of δo = 37 [µm], δmin = 3.8 [µm], Cni = 10-10 [m/Pa], ρrock = 2900 [kg/m3], ν = 0.3, and Eore/Eb = 0.31. The results from the model suggest there are two flow systems, a flow system from min-ing activities which is superimposed onto a shallow ambient groundwater flow system controlled by distributed recharge and stream locations. Dewatering creates a sink that captures water from the vicinity of the mine as well as from the shallow aq-uifer system. Mining and dewatering cre-ate deformation at the scale of the mine. The greatest deformation occurred at the surface, in the region representing the open pit and upper mine workings. In this re-gion maximum subsidence reached almost 0.2m. There were also small regions of uplift below the mine workings, most nota-bly below the lower portions of the work-ings, with a maximum uplift of almost 0.031m. Furthermore there was defor-mation laterally around the mine workings. Primarily it was subsidence, however, there was some uplift adjacent to the mine work-ings at the lowest depths of the workings. Mining resulted in several changes to the stress field within roughly 1 km around the excavations. It resulted in increased com-pressive stress around the edge of the

workings and an increase in tensile stress within the workings themselves. The change in the magnitudes of the stresses around and in the mine workings is typical-ly on the order of 10’s of MPa. With the calibration parameters presented above and the steady state version of the model, which represented pre-mining conditions, an estimate of the pre-mining stress-state and stress gradients in the region was made. The vertical/1st principle stress gra-dient is on the order of 0.03 [MPa/m] and is about 3 times larger than the 2nd and 3rd principle stress gradients which are on the order of 0.01 [MPa/m]. Intermediate Scale Transport of Nanoparticles in the Vadose Zone Emerson, H. P.1, hilaryp@clemson.edu, A.E. Hart2, J.A Baldwin1, T.C. Waterhouse1, C.L. Kitchens2, O.T. Mefford3, and B.A. Powell1 1Environmental Engineering and Earth Sci-ence, Clemson University, Clemson, SC, 2Chemical and Biomolecular Engineering, Clemson University, Clemson, SC, 3Mate-rials Science Engineering, Clemson Uni-versity, Clemson, SC The use of nanoparticles in industrial and commercial applications has increased dra-matically in the past ten years. Because these particles will inevitably enter the en-vironment through nonpoint sources from consumer products and point sources from industry and waste streams, it is necessary to understand the risks from environmental releases to humans and the environment. The objective of this study was to investi-gate the potential mobility of nanoparticles in the unsaturated zone, between the ground surface and the water table. Five different nanoparticles were focused on including: iron oxide as bare nanoparticles

13

and coated with Suwanee River natural or-ganic matter (SR-NOM) and zerovalent silver nanoparticles capped with citrate (C6H8O7), SR-NOM, or dodecanethiol with average particle sizes of 10 nm and 30 nm for the magnetite and silver nanoparti-cles respectively. The experimental setup included six separate lysimeters, columns with a 4” diameter and 22” length with catchment of rainwater effluent into 1-liter collection bottles, which were housed in a recycled biological contactor rack. A con-trol lysimeter was prepared without nano-particles for the establishment of back-ground iron and silver concentrations in the sandy loam sediment and for monitoring of soil moisture content and temperature as the large monitoring probes would have impacted the flow through the remaining five lysimeters. A probe was placed near the top, middle, and bottom sections of the control lysimeter with an additional probe placed 10” below ground for comparison.

After one year of exposure to the envi-ronment and transport of ≈2 pore volumes of water through the columns, break-through of nanoparticles from the lysime-ters was insignificant with respect to the total masses of particles added to each sys-tem as shown in Table 1. The columns were segmented into 1 cm slices by extru-sion, homogenized, microwave digested in triplicate, and analyzed by inductively cou-pled plasma mass spectrometry (ICP-MS). After one year of exposure, > 99% of the nanoparticles moved less than 5 cm. Digi-tal photos taken during the coring process show drastic differences from the homoge-nous sources initially placed into the lysim-eters with macroscopically heterogeneous sources with large (mm-sized) aggregates throughout in all but the silver NOM source. Aggregation was confirmed in all sources on a microscopic scale by trans-mission electron microscopy (TEM)

(Figure 1). The aggregates in the silver-citrate and silver-NOM source appear to be associated with stripping of the iron oxide and clay coatings from soil particles as seen by the “bleaching” effect on the soils. TEM analysis also supports association of particles with the edges of clay sheets and goethite rods naturally present in soil coat-ings and aggregate digestion of a large sil-ver citrate aggregate confirms that particles aggregated with the colloids (soil coatings) naturally present in the soils. In addition, transport of silver and magnetite nanoparti-cles coated with SR-NOM as nanoparticles was confirmed to 3cm and 2cm from the source, respectively. The soil coatings ap-pear to be the primary constituent control-ling the aggregation and transport of nano-particles, however, the concentration of the nanoparticles may also play an important role in the mechanisms of aggregation. These results imply that nanoparticle transport in unsaturated systems will be significantly hindered relative to the ex-pected transport based on laboratory exper-iments with quartz, silica or other pure mineral phases under saturated conditions with different mechanisms possibly con-trolling transport in unsaturated systems due to wet-dry cycling.

Figure 1: [clockwise from top] TEM images of (i) Bare iron oxide source nanoparticle aggre-gate, (ii) iron oxide NOM aggregate, (iii) silver SR-NOM nanoparticles in source, (iv) EDX mapping for silver to confirm presence of silver nanoparticles

Sample ID

Effluent Iron (µg)

Effluent Silver (µg)

Effluent Recovery

Solid Phase Recovery

Bare FeOx 0 - 0% 84.1%

FeOx-NOM 15.1 - 0.00015% 56.2%

Ag-NOM 4.7 1.0 0.00005% 14.6%

Ag-Cit 4.2 0.6 0.00004% 6.5%

Ag-thiol 11.7 2.8 0.00012% 68.0%

Table 1: Recovery of Aqueous and Solid Phases from Lysimeters

14

15

An Examination of Plutonium Re-dox Chemistry on the Surfaces of Hematite, Silica, and Montmorillo-nite using XANES Estes, Shanna L., sestes@clemson.edu, and Amy E. Hixon, Environmental Engi-neering & Earth Sciences, Clemson Uni-versity, Clemson SC; Yuji Arai, School of Agriculture, Forestry, and Environmental Science, Clemson University, Clemson SC; and Brian A. Powell, Environmental Engi-neering & Earth Sciences, Clemson Uni-versity, Clemson SC The presence of plutonium in the geo-sphere poses a major long-term environ-mental concern due to its toxicity and the long half-lives of several isotopes. There-fore, understanding the mechanisms re-sponsible for enhancing or retarding the mobility of plutonium is important for risk management. The oxidation state of pluto-nium is the primary factor controlling sub-surface mobility, such that Pu(IV) is gener-ally considered immobile due to a high sorption affinity for mineral surfaces and decreased solubility compared to oxidized plutonium species. Although numerous researchers have demonstrated surface me-diated plutonium reduction, detailed spec-troscopic studies of plutonium redox chem-istry at the mineral surface are not available in the literature.

In this work, x-ray absorption near edge structure (XANES) spectroscopy was used to examine the redox chemistry of plutonium on the surfaces of hematite, high-purity quartz, and Na-montmorillonite. The plutonium oxidation state reacted with these minerals was initially Pu(III), Pu(IV), or Pu(V/VI). Regardless of the mineral or initial plutonium oxidation state present in the system, XANES data indicated that Pu

(IV) is the primary oxidation state at the surface. Additionally, samples were im-aged using electron microscopy to identify any potential plutonium nano-precipitates. For the minerals systems initially reacted with Pu(III) and Pu(V/VI), plutonium na-noparticles were observed on the hematite and silica surfaces, respectively. These results support a hypothesis of a thermody-namic gradient for sorbed Pu(IV).

Migration of Exsolved CO2 Fol-lowing Depressurization of Satu-rated Brines Falta, Ronald W. 1, faltar@clemson.edu, Lin Zuo2, Larry Murdoch1, and Sally M. Benson2 1Department of Environmental Engineering and Earth Sciences, Clemson University, Clemson, SC; 2Department of Energy Re-source Engineering, Stanford University, CA Geologic disposal of supercritical carbon dioxide in saline aquifers and depleted oil and gas fields will cause large volumes of brine to become saturated with dissolved CO2 at concentrations of 50 g/l or more. As CO2 dissolves in brine, the brine densi-ty increases slightly. This property favors the long-term storage security of the CO2 because the denser brine is less likely to move upwards towards shallower depths. While dissolved phase CO2 poses less of a threat to the security of shallower drinking water supplies, there are plausible mecha-nisms by which the CO2 laden brine could be transported to a shallower depth, where the CO2 would come out of solution (exsolve), forming a mobile CO2 gas phase.

Recent laboratory experiments of the

16

exsolution process show that the exsolved gas phase relative permeability is much lower than relative permeabilities measured during CO2 core floods. Numerical simu-lations of upward brine migragion through an open fault were performed using TOUGH2-ECO2N with the two types of relative permeability functions. When tra-ditional coreflood relative permeabilities are used, upward flow of a CO2 saturated brine leads to exsolution and the develop-ment of a highly mobile CO2 gas phase. When exsolution relative permeabilities are used, the tendency for the exsolved CO2 to migrate as a separate phase is greatly re-duced, and the exsolved CO2 can partially block brine flow through the open fault.

Heterogeneity of Groundwater- stream Water Interactions in a Headwaters Southern Appalachian Watershed, Cullowhee, NC Ferri, Kelly, khhorne1@catamount. wcu.edu, J. M. Bright, S. H. Printz, M. Lord, and D. Kinner, Department of Geo-sciences and Natural Resource Manage-ment, Western Carolina University, Cullowhee, North Carolina; and T. Camp-bell, Division of Water Quality, North Car-olina Department of Environment and Nat-ural Resources, Swannanoa, NC Groundwater-stream water interactions within a headwaters stream system in the Appalachian Mountains are spatially and temporally variable. Characterization of groundwater-stream water interaction is important in predicting water budgets, as-sessing impacts of development on ground-water and surface water supplies, and as-sisting in contamination cleanup. Studies were conducted at three sites in a headwa-ters watershed to discern variations in

groundwater inputs and outputs due to geo-morphology and topography. The studied part of the watershed is a hydrologic re-search station established on the campus of Western Carolina University in partnership with the North Carolina Department of Natural Resources with support of the Na-tional Science Foundation. The watershed has a mixed land use history with gullying at the hillslope-channel interface, indicat-ing past geomorphic instability. The station includes over 40 nested shallow groundwa-ter wells installed on three alluvial and/or colluvial sites. The sites represent different geomorphic settings at watershed scales of 0.4, 4.4 and 62 km2.

Gribble Gap (GG), Long Branch (LB), and Cullowhee Creek (CC) are study sites that are continuously monitored in the re-search station. GG is a low energy first or-der stream flowing through colluvial de-posits. LB stream flows through a mixture of colluvial and alluvial deposits and is supplied by groundwater on the left and right banks by a hillslope and a colluvial fan, respectively. CC includes a flat alluvi-al upstream reach (referred to as the flood-plain reach) surrounded by > 1 meter de-posits and greater than 9 meters to bedrock. The downstream reach (referred to as the narrows reach) is surrounded by hillslopes and depth to bedrock is around one meter. Sub-sites were chosen within each location to permit comparison between as well as within sites. Methods for examining groundwater-stream water interaction in-cluded temperature probes, stream profiles, bed material characterization, and analyses of hydraulic head data in near stream pie-zometers. All of these methods are used to analyze how groundwater enters and exits the stream. Variations in temperature pat-terns at sub-sites that were within centime-ters of each other indicate complex spatial heterogeneity at GG, including reaches

17

where the groundwater and stream are not connected. Higher overall temperatures on the right bank of LB relative to the left in-dicate that groundwater input into the steam is controlled by geomorphic setting, with greater flow from the colluvial fan than the hillslope. At the downstream CC site, stream bed surface temperature pat-terns and water levels in piezometers in-stalled in the stream show greater ground-water and stream water interactions within the floodplain reach compared to the nar-rows, bedrock reach. Topography and spa-tial variability in local geologic settings are major controls in determining groundwater-stream water interactions. Causes of the variation in groundwater interaction with surface water are a function of position within the watershed. Extended research about topography within study sites and across temporal variations furthers the un-derstanding of heterogeneity within a stream system.

Influence of High Permeability Proppant-Filled Hydraulic Frac-tures on Ambient Groundwater Flow Fields and Resulting Benefits for Passive Remediation Hall, Richard, rhall@frx-inc.com, and William Slack, FRx Inc, Blue Ash, OH; and Larry Murdoch, Environmental Engi-neering and Earth Sciences, Clemson Uni-versity, Clemson, SC Passive remediation systems require a moderate upfront investment; however, labor or energy inputs over the remaining treatment duration can be small to non-existent. This aspect of passive systems has made them popular alternatives to tradi-tional, energy-intensive, active approaches such as pump and treat and air sparging. A

passive approach commonly utilized in contaminated saturated zones involves fill-ing an excavated trench with reactive sol-ids. Dissolved contaminants are destroyed as they are transported to and through the trench by ambient groundwater flow. Filled trenches are referred to as permeable reac-tive barriers (PRBs) when high permeabil-ity solids such as granular iron are used. Researchers have shown that ambient flow-lines tend to deflect towards PRBs, and that the extent of this condition increases as the trench to formation permeability ratio in-creases. This deflection of flow results in a far-field capture zone with a cross sectional area that is larger than that of the PRB, which is beneficial with respect to total volume of groundwater treated per time.

Hydraulic fracturing is an injection methodology that has been utilized for en-hancement of a wide variety of remedial processes for nearly two decades. The pro-cess enables emplacement of granular sol-ids (proppant) in subsurface formations without excavation of native materials. Re-medial hydraulic fractures have been creat-ed from 1 to 150 ft bgs with typically 500 to 2500 lbs of solids. The resulting prop-pant distribution takes on the geometry of a broad, thin, semi-horizontal sheet around the point of injection. The presence of a high permeability proppant-filled fracture can distort the naturally occurring fluid flow field in a manner that is similar to that of PRBs. Flowpaths tend to converge on the upstream side of the fracture and di-verge on the downstream side of the frac-ture.

A 3-dimensional, subsurface flow sim-ulator was used to characterize resulting flow patterns towards cylindrical (disk-shaped) fracture geometries. Suites of sim-ulations were designed A) to characterize the resulting dimensions of passive hydrau-lic fracture capture zones as a function of

18

fracture dimension and fracture/formation permeability ratio; and B) to develop an analysis for predicting contaminant resi-dence times within the fracture based on point of origin within the far-field. Results indicate that the far field capture zone for a circular, flat-lying hydraulic fracture is el-lipsoid in shape and oriented perpendicular to the horizontal flow direction. Capture zone dimensions consistently increase as fracture to formation permeability ratio in-creases. Changes in fracture aperture-diameter ratio do not significantly affect capture zone dimension while the ratio is small. However, this trend does not hold true as fracture aperture-diameter ratio in-creases because interception plays an in-creasing role. Maximum residence time occurs along flowlines that originate near the centroid of the capture zone and de-crease towards the edges. When scaled to maximum residence time, the residence time distributions were found to be a func-tion of fracture/formation permeability ra-tio. Residence times along particular flow-lines scale to the ambient formation flux.

Installation of PRB’s allows emplace-ment of large masses of remedial solids, however, the cost of trenching and disposal of excavated materials can be substantial. While the mass deliverable per hydraulic fracture is relatively small, the process avoids complications associated with exca-vation and is extremely inexpensive by comparison. Comparable total mass deliv-ered at a site can also be achieved by em-placement of multiple fractures. Analyses indicate that strategic emplacement of high permeability fractures can result in captures zones on the scale achieved by PRBs, and that sufficient contaminant residence times occur for the bulk of flow originating from the capture zone. These findings explain the positive remedial performance of hori-zontal, iron-filled hydraulic fractures that

have been created for the purpose of de-stroying chlorinated solvents.

Naranpur Express: Understanding Environmental Decision-Making Processes through Serious Game Development Hanna, A.C., and S.M.J. Moysey, Envi-ronmental Engineering and Earth Sciences, Clemson University, Clemson, SC; C. Mobley, and E. Shealy, Sociology and An-thropology, Clemson University, Clemson, SC; and H. Pai, G. Ilango, A.A. Mast, and S. Sathyanarayan, Computer Science, Clemson University, Clemson, SC Serious games are computer games with a primary purpose other than entertainment. Serious games are frequently used for training purposes, and can be used for edu-cational and research purposes, increasing student interest and level of interaction as well as allowing researchers to collect data about emergent player behavior.

The Naranpur Express simulation is based on a previously existing multiplayer role-playing game, where each player man-ages a small farm in rural India. Player goals include subsistence, upward econom-ic mobility, and mitigation of environmen-tal impact. Hydrologic and agricultural models are used to connect each player's small-scale decisions with their more far-reaching, and often difficult to perceive environmental impacts. This approach al-lows students to learn by discovery, experi-encing first-hand the challenges of overuse of groundwater, fertilizers, and pesticides. Integration of new and rapidly developing social media techniques allows players to discuss solutions to their shared challenges, and help define a set of formal or informal

19

rules governing their community. Previous versions of this game were

implemented on paper, or in a spreadsheet run on each student's laptop. However, moving this simulation to an interactive online setting will allow us to study aggre-gate, as well as spatially varying effects of player decisions on economic and environ-mental outcomes. By coupling both physi-cal and economic models with the real dy-namics of player behavior, and considering the social and cultural aspects of agricul-ture, we can investigate the decision-making processes that control real environ-mental outcomes. By varying the types of information available to players, we can investigate how access to different kinds of information drives environmental decision-making. This can help identify key misun-derstandings, thereby benefiting education and outreach efforts related to environmen-tal justice and sustainability issues.

Electrical Response of Grain Sur-face Ion Adsorption Processes Ob-served by Spectral Induced Polari-zation Measurements Hao, Na, nhao@clemson.edu, and Ste-phen Moysey, Environmental Engineering and Earth Sciences, Clemson University, Clemson, SC Two sets of silica gel column experiments were designed to understand the change in the electrical response (i.e., complex con-ductivity) associated with ion sorption on the surface of silica gel. The first experi-ment was conducted by pumping different pH sodium chloride solutions to the col-umn continuously and monitoring the SIP signals over time. During the 46 days ex-periment, the peak response of the imagi-

nary conductivity increased from 1.19 to 37.5 s/cm and became stable, and the av-erage real conductivity increased from 2218 to 3418 s/cm. The record of the pH in inflow and outflow implied that the sili-ca gel buffered the solution. Increasing of the solution pH promoted de-protonation and adsorption of sodium on surface. The sorbed sodium on silica surface increased the surface ion density, which is a factor affecting SIP signals by grain polarization.

The second experiment was conducted for 8 days, during which time calcium chloride and sodium chloride solutions of the same concentration displaced each oth-er every other day. When the sodium solu-tion was replaced by the calcium solution, the peak response of the imaginary compo-nent of complex conductivity decreased from 19.76 to 7.9�s/cm, whereas the real part of complex conductivity increased from 1025 to 1533�s/cm. On the sixth day of the experiment, rather than using equiv-alent concentrations for the solutions, the electrical conductivity of the calcium chlo-ride solution was fixed to be nearly equal to that of sodium chloride solution. In this case, the peak imaginary part of complex conductivity increased slightly to 9.1 re-sponses observed for the higher calcium concentrations. The real conductivity was 1055 S/cm which was similar to the values measured for the sodium chloride solu-tions. The observed imaginary conductivity differences between sodium and calcium could be explained by different complexa-tion mechanisms on the surface of the sili-ca gel. A difference of relaxation frequency between sodium and calcium was not de-tected, however, which may be related to the fact that diffusion into nano-scale pores in silica gel is not accounted for. The re-sults indicate that the SIP method can ef-fectively monitor changes in the composi-tion of solutes sorbed to a mineral surface.

20

Rail to Rail – A Brownfields Agree-ment Based on Nothing Harriger, Joselyn, jharrig-er@harthickman.com, and Matt Bram-blett, Hart & Hickman, Charlotte, NC The Norfolk-Southern Intermodal Facility in North Charlotte has more than a century of industrial history. The City of Charlotte and CATS have worked for years to extend the successful LYNX Blue Line light rail system that exists in South Charlotte. The Blue Line Extension is a proposed light rail line in North Charlotte which will reach the UNC-Charlotte campus. The Norfolk-Southern Intermodal facility is along the Blue Line Extension project and is a neces-sary property for the Blue Line Extension. Conveniently, Norfolk Southern is relocat-ing intermodal operations to the airport. Because of access limitations prior to an estimated property acquisition date in 2014, the City was unable to conduct typi-cal due diligence sampling activities. The City opted to enter the property to the NC Brownfield program, and the parties are completing a Brownfields Agreement with no soil or groundwater data. The Brown-fields eligibility was based on the percep-tion and likelihood of contamination based on the site history.

As part of the Brownfields process, an Environmental Action Plan (EAP) has been prepared. The EAP consists of a plan for assessment once the property is acquired and a plan to manage contaminated soil and water, if found during redevelop-ment. With the EAP in place, the construc-tion schedule is expected to “stay on track.”

This talk will provide a historical re-view of potential environmental concerns at the intermodal facility, discuss the pro-

posed reuse of the property for light rail operations, provide information on the types of Brownfields paths available through NC DENR, and provide tips for preparing an EAP to facilitate redevelop-ment. Oxidation or Reduction – Not Mu-tually Exclusive Options Hicks, Patrick M., pat-rick.hicks@fmc.com, FMC Environmental Solutions, Raleigh, NC; Jim Mueller, FMC Environmental Solutions, Freeport, IL; and Philip Block, FMC Environmental Solutions, Philadelphia, PA Many compounds can be degraded via oxi-dative or reductive processes. The decision process used to select an option should be prefaced with the understanding that the technologies are not mutually exclusive, or related such that each excludes or pre-cludes the other. Instead, the selection pro-cess should include consideration of both oxidative and reductive processes, but per-haps different applications over the course of the remediation project.

Various in-situ chemical oxidation (ISCO) technologies using oxidizing agents such as hydrogen peroxide (Fenton’s chemistry), permanganate, ozone, and acti-vated persulfate have been used to remedi-ate impacted environments. Each of these oxidants and their activators offer unique features, and they can be very effective on a broad range of more oxidized (chlorinated) hydrocarbons to more re-duced (petroleum) hydrocarbons. This presentation will focus on the application of activated persulfate across a spectrum of contaminants.

In-situ chemical reduction (ISCR) ap-proaches using a combination of zero-valent iron and controlled release carbon

21

generate environmental conditions that can facilitate the chemical reduction of oxi-dized/chlorinated hydrocarbons and other contaminants such as metals.

Many factors may need to be consid-ered when making a decision to use ISCO and ISCR approaches for a specific site. These may include the following, which will be discussed as part of this presenta-tion: Targeted treatment area (source remov-

al, plume control, or both) Contaminant characteristics, concentra-

tions, and goals Presence of free product or product re-

siduals Desired clean-up time Aquifer geochemistry (aerobic to an-

aerobic) Soil oxidant demand Hydrogeology and groundwater flow

velocity Application method (soil blending, di-

rect injection, injection through wells, etc.)

Ambient Deformation of Permea-ble Fractures Hisz, David, dhisz@clemson.edu, and Larry Murdoch, Environmental Engineer-ing and Science Department, Clemson Uni-versity, Clemson, SC Permeable fractures deform as a result from a change in effective stress or changes in fluid pressure. Until recently, observing the deformation with borehole devices re-quired large changes in fluid pressure (> 6 kPa) to detect measurable fracture defor-mation. As the resolution of borehole in-struments have increased, it has become possible to detect the response of a permea-ble fracture to smaller changes in pressures

(<100 Pa). The improved resolution has enabled instruments to detect responses caused by ambient stresses, such as those resulting from barometric fluctuations or Earth tides. Evaluating effects of these am-bient stresses is the objective of this study.

This investigation was conducted using the Tilt-X instrument, which includes a Differential Variable Reluctance Transduc-er (DVRT) to measure displacements be-tween a pair of anchors, and a bi-axial tilt-meter to measure tilt. The device is low-ered into a borehole and set in place by ex-tending two anchors against the borehole wall. Pressure in the well is changed solely by diurnal fluctuations in barometric pres-sure or Earth tides. Under ambient condi-tions, fractures open and close on a diurnal period that correlates to barometric load-ing. The tilt varies semi-diurnally apparent-ly in response to earth tides. Fracture com-pliance is approximately 5 m/m in re-sponse to barometric fluctuations, whereas, it is approximately 1 m/m head change during pumping or slug tests.

We conducted two field tests deploying the Tilt-X on two permeable fractures (25 and 35 m depth), for periods of 2 and 12 weeks, respectively. Water level, baromet-ric pressure, axial displacement and bi-axial tilts were recorded at a 1 Hz sample rate. As barometric loading increases, the water table lowers, increasing the internal fluid pressure and opening the fracture. Typical axial displacements under ambient conditions range from 10 to 30 nm.

Two significant earthquakes (>7.5 magnitude) occurred during the 12-week-long monitoring at the 35-m-deep fracture. The instrument responded strongly to these two events, indicating opening displace-ments of 500 nm after each earthquake. This response is 10x greater than changes due to barometric loading, and it may be related to the changes in permeability that

22

have been reported to follow distant earth-quakes.

Fracture responses from ambient baro-metric loading provide additional insights into the mechanical and hydraulic proper-ties of a fracture compared to the hydraulic stresses caused by typical pumping tests. Diurnal changes in barometric pressure cause factures to open and close, in a pulse-like fashion. This transient ambient behav-ior may influence the flow and transport properties of a fractured rock aquifer.

Investigation of the Changes in Uranium, Selenium, and Radium Speciation and Mineralogy that Occur During Uranium In-Situ Recovery Operations Hixon, Amy E., aeratli@clemson.edu, and Brian A. Powell, Environmental Engineer-ing & Earth Sciences, Clemson University, Clemson SC During uranium in-situ recovery (ISR) a lixiviant (i.e., leaching solution) is injected into a subsurface, uranium-bearing sand-stone. The composition of the lixiviant is such that uranium is oxidized and mobi-lized within the confined aquifer. Dis-solved uranium is then pumped to the sur-face for further processing. U.S. Nuclear Regulatory Commission regulations re-quire ISR uranium mining facilities to re-store groundwaters affected by mining op-erations. Restoration methods, such as groundwater flush, reverse osmosis, and hydrogen sulfide (H2S) injection, have the goal of returning the subsurface environ-ment to its original baseline condition to ensure no significant long-term impact on water quality.

Very few examples of geochemical modeling of the groundwater restoration process exist in the open literature. How-ever, these existing models focus on the water quality of the confined aquifer and neglect mineralogy. In this study, the one-dimensional transport functionality of PHREEQC was used to monitor uranium, selenium, and radium speciation and min-eralogy across all phases (i.e., baseline, mining, and restoration) of an ISR opera-tion. The model takes into consideration redox, dissolution, precipitation, aqueous complexation, and sorption reactions. Re-sults indicate that, within the constructs of this conceptual model, while the ground-water quality of the ISR site post-remediation may resemble baseline water quality, the mineralogy of the system is different. Results are compared to the pub-lished water quality data from the Highland Uranium Project. Model limitations— in-cluding kinetics, lack of specific miner-alogical characterization, and weaknesses of the thermochemical database— will be discussed.

Case Study: Full Scale Treatment of a TCE Groundwater Plume Us-ing ISCO at an Active Manufac-turing Facility in Spartanburg, South Carolina Hollifield, Ed, ed.hollfield@erm.com, and Jennifer Byrd, Environmental Resources Management, Charlotte, North Carolina A Chlorinated Volatile Organic Compound (CVOC) plume originating from former degreasing operations extends over approx-imately 7 acres on-site at an active manu-facturing facility in Spartanburg. South Carolina. The primary groundwater con-

23

taminant is Trichloroethene (TCE) with elevated concentrations near source areas (former degreaser and waste disposal areas) in the western section of the facility and extending west and off-site. The Site is lo-cated in the Inner Piedmont Belt of the Piedmont Physiographic province of South Carolina, which is characterized by meta-morphic and igneous rocks of varying age overlain in the uplands by saprolitic silty to clayey soils derived by weathered and vari-ably decomposed bedrock. The three main piedmont aquifer zones generally encoun-tered in the Piedmont are present at the site including the saprolite, partially weather rock (PWR) and bedrock aquifer zones. Groundwater contamination is present in each of the aquifer zones with the highest CVOC concentrations detected in the PWR zone.

After completion of a remedial alterna-tives analysis and evaluating several poten-tial groundwater remediation technologies through pilot tests, in-situ chemical oxida-tion (ISCO) was selected as the primary on-site technology used for groundwater treatment.

The corrective action approach utilized ISCO technology to remediate the CVOC affected saprolite, PWR and shallow bed-rock saturated zones from the historic source areas of the site to the western prop-erty boundary. The ISCO treatment meth-od consisted of injecting sodium perman-ganate (NaMnO4) into the saprolite aquifer zone utilizing direct-push injection points (DPT). The NaMnO4 was delivered to the site using 72 DPT points for the injection of approximately 16,000 gallons of 5% so-dium permanganate solution to the Site. Injection points were installed on 20-foot spicing, given an estimated radius of injec-tion of 10 feet. Oxidant injection was ac-complished by using DPT to advance an injection point to multiple discrete vertical

intervals (e.g., every 2-5 feet of vertical thickness) within the saturated surficial aq-uifer zones to depths ranging from approxi-mately 27 to 55 feet below land surface (ft bls). This approach facilitated vertical dis-tribution of oxidant through the saturated zone. The NaMnO4 solution has a specific gravity of approximately 1.1, and thus was expected to migrate vertically downward over time, allowing for treatment within the deeper PWR aquifer and the PWR / bedrock transition zone and shallow bed-rock. Initial treatment was conducted Sep-tember 2008 with post treatment monitor-ing since that time.

CVOC concentrations in the historical-ly most impacted on-site source areas have been treated with results of an 80 to 90% reduction in contaminants since initial in-jection. CVOC concentrations in the on-site well cluster immediately downgradient of the ISCO treatment area shows an ap-proximately 60% decrease in CVOC con-centrations, further evidence that the site is effectively being treated using ISCO. No significant rebounding of site contaminants has been observed during the course of this treatment which is generally atypical of ISCO treatment using NaMnO4 in the Piedmont. Based on the most recent post ISCO sampling results, injected permanga-nate appears to have been largely utilized at the site since 2008 and a second full scale injection is planned for Spring 2013.

24

PCE Vapor Intrusion Assessment and Mitigation – Former Manu-facturing Site, Eastern NC Hollifield, Ed, ed.hollfield@erm.com, and Joshua Fell, Environmental Resources Management, Charlotte, NC A Chlorinated Volatile Organic Compound (CVOC) plume originating from former degreasing operations extends over approx-imately 12 acres at a former manufacturing facility in Rocky Mount, North Carolina. The primary groundwater contaminant is Perchloroethene (PCE) with elevated con-centrations near source areas in the south-ern portion (~50,000 square feet) of the former manufacturing facility. The facility is being redeveloped with sections leased under a brownfields agreement, which lim-its potential remediation options within the facility.

The site is located in the Mesozoic and Cenozoic Coastal Plain geologic and physi-ographic province of NC where Tertiary marine sediments overlap Paleozoic crys-talline igneous, metamorphic, and sedimen-tary rocks of the Eastern Slate belt. The surficial geology beneath the site is com-plex and consists of unconsolidated inter-fingering sequences of clayey to sandy ma-rine sediments in terrace deposits of the Sunderland formation to depths of 20 to 50 feet below ground level. The terrace depos-its are underlain by the Pliocene-age York-town formation, consisting of marine clays, silts, sandy clays, and shell marl. The Cre-taceous Pee Dee formation underlies the Yorktown formation around Rocky Mount.

Groundwater remediation at the site, consists of using pump and treat technolo-gy for mass removal in the source areas and containment at the downgradient prop-erty boundary. Additionally, bioremedia-

tion has been used successfully to treat off-site downgradient distal sections of the PCE plume. A series of sub-slab soil gas and indoor air investigations indicated the presence of CVOCs, primarily PCE, in in-door air at the facility. Concentrations were found to be significantly above the risk-based exposure values limiting the use of the building for human occupation and continued redevelopment. Residual CVOCs beneath the former degreaser room and manual degreaser area, located in the southern part of the building, are the prima-ry sources of the CVOCs detected in in-door air.

To allow continued occupation and ad-ditional development of the former indus-trial building by reducing VOC concentra-tions in indoor air, ERM first pilot tested a small sub-slab vapor depressurization sys-tem (SSDS) in the source area to evaluate the efficacy of the SSDS technology to re-duce vapor intrusion within the building. The pilot test was run for three months in-dicating positive results for the technology at the site. Based on the results of the pilot test, ERM then designed and installed a full scale SSDS throughout a 50,000 square foot part of the building. The SSDS con-sists of 28 vapor depressurization points with overhead piping connected to a robust centralized vacuum blower system. Vacu-um was applied to the sub-slab which was then balanced over six months using a se-ries of sub-slab vacuum monitoring points and individual depressurization point vacu-um data.

During the first year operating the SSDS, concentrations of VOCs in indoor air have decreased to trace levels and well below applicable NC VI action levels. Over the first year of operation, PCE con-centrations have been reduced by an aver-age of 96% in the indoor air, and are now within permissible limits for commercial

operations. The building is now currently being occupied.

Treatment of Selenium as a Con-stituent of Ecological Concern in Energy-Produced Waters Huddleston, Matt, Cardno ENTRIX, Clemson, SC; John H. Rodgers Jr., School of Agricultural, Forest, and Envi-ronmental Sciences, Clemson University, SC; James W. Castle, Environmental En-gineering and Earth Sciences, Clemson University, SC; and Michael Spacil, Dia-mond V, Greenville, SC Waters associated with energy production, including waters from coal ash basins, flue gas desulfurization (FGD), oil & gas pro-duction, and petroleum refineries, can con-tain selenium as a constituent of ecological concern. An effective and reliable approach to treating selenium in these waters is needed to meet stringent water discharge limits established under the National Pollu-tant Discharge Elimination System (NPDES) and the Clean Water Act. Con-structed wetland treatment systems (CWTSs) have been developed that target biogeochemical mechanisms for removal of selenium and other constituents (e.g., mercury, arsenic, lead, copper, oil & grease). Case studies using CWTSs for se-lenium removal in waters associated with energy production will be presented. In pi-lot-scale CWTSs for FGD waters, selenium concentrations decreased from approxi-mately 4 mg/L in the influent to less than 1 mg/L in the effluent. In subsequent studies focused on enhancing selenium removal from produced waters using organic amendments to the wetlands, inflow seleni-um concentrations of approximately 50 µg/L decreased to 3.4-9.8 µg/L, depending on the experimental treatment. The case stud-

ies illustrate that CWTSs can reliably re-move selenium to <5 µg/L to meet strin-gent discharge limits. Representative Pharmaceuticals and Pesticides in Small South Car-olina Streams: A Catchment Based Approach to Identify Potential Im-pacts and Sources Jones, Alan J., ajones6@clemson.edu, Clemson Institute of Environmental Toxi-cology, Pendleton, SC and E. R. Carra-way, Environmental Engineering and Earth Sciences, Clemson University, Clemson, SC Anthropogenic activities have long been studied as potential sources for contamina-tion of water in nearby streams, however the majority of the research conducted has been focused on larger water bodies in ur-banized areas. Little is known about the impacts these activities have on small, rural streams. Research in small, rural water-sheds may have the benefit of lower back-ground contamination and lower thresholds of effect than larger urbanized watersheds. In 2006, Clemson University and the South Carolina Department of Natural Resources embarked on a multi-year study to investi-gate approximately 400 small streams throughout the state of South Carolina. This study assessed chemical pollution in the water column, biomarkers of effect, and fish and invertebrate populations and com-munity structure. This presentation will focus on the occurrence and distribution of organic pollutants in small streams of South Carolina and relationships with land cover. Organic pollutants are characterized using liquid chromatography – tandem mass spectrometry after concentration through an Oasis HLB extraction cartridge. Analytes of interest are estrone, 17β-

26

estradiol, 17α-ethynylestradiol, atrazine, caffeine, triclosan, diphenhydramine, naproxen, and ibuprofen. Results indicate that organic pollutants are widespread in small streams, however they are not often related to land cover. Results also indicate the presence of high concentration areas (i.e. hot spots) of many of the pollutants studied. Forward and Inverse Modeling of WellBore Deformation During CO2 Sequestration

Kim, Sihyun, sihyun@gatech.edu, Georgia Tech, Atlanta, GA; Lawrence C. Mur-doch, lmurdoc@clemson.edu, Clemson University, Clemson, SC; Leonid N. Ger-manovich, leonid@gatech.edu, Georgia Tech, Atlanta, GA; and Stephen M. Moy-sey, smoysey@clemson.edu, Clemson Uni-versity, Clemson, SC

Well bores always deform in response to injection or recovery of fluid. In extreme cases the deformation is catastrophic and the well can be ruined, but in routine cases the small elastic deformation has the poten-tial to be an important diagnostic tool that improves the efficiency and safety of CO2 sequestration. Including deformation meas-urements along with the pressure signal during short-term hydraulic well tests will improve estimates of formation properties and heterogeneities, and this will lead to forecasts of injectivity and pressure re-sponse to CO2 injection.

The feasibility of using wellbore defor-mation as a diagnostic tool is being evalu-ated by addressing three primary questions: What is the magnitude and pattern of ex-pected deformation? Can this signal be measured? Can these measurements be in-terpreted? The first question is being evalu-

ated by developing a series of theoretical analyses that represent wells in various sce-narios typical of CO2 sequestration. The conceptual model is that well casing is an elastic tube that is loaded during the well completion process. This external load compresses the casing with a compliance of 10 to 40 microns of radial displacement/MPa load. During injection, the casing moves both radially and axially. Internal fluid pressure causes the casing to bulge, and poroelastic effects in the injection for-mation unload the casing and cause it to move radially outward. Pressure on adja-cent confining units, and interaction with the ground surface cause the casing to stretch longitudinally where it contacts the injection interval, and it can be compressed in the overlying confining units. Radial dis-placements are on the order of tenths of microns to several microns, and axial strains are 10 microstrain or more, accord-ing to simulations. Effects in confining units are particularly interesting because they show a time dependency that results from the vertical propagation of pressure from the injection interval —the casing can be compressed as the confining unit be-comes pressurized. This suggests that it could be feasible to characterize the verti-cal permeability of a confining unit by monitoring pressure change through casing deformation.

Measuring small deformations in deep wells will be required for this technique to be viable. We have evaluated high resolu-tion electromagnetic sensors, fiber optic strain gauges, as well as electrolytic tiltme-ters. The evaluation process has included the development and evaluation of full-scale prototype downhole tools designed to measure 3D deformations. Field testing demonstrates that it is possible to measure displacements less than 0.1 micron, and strains of less than 0.1 microstrain at

27

depths of several 10s of meters. These re-sults are encouraging because they suggest that it could be feasible to measure defor-mations indicated from the theoretical anal-yses at greater depths. Interpretation of de-formation signals is expected to be con-ducted initially using heuristic methods.

Variability of poroelastic parameters and geometric values are tested in sensitivi-ty analysis. The range of measurement can be estimated based on the observed input parameters, and moreover, the dominating parameters can be expected for the individ-ual measurements. We are also developing inversion methods using Markov Chain-Monte Carlo techniques for quantitative parameter estimation. Union High School Gun Range Soil testing, Delineation, and Treatment Lauber, Kenneth A., klauber@fandr.com, and Hestir, Benjamin D., bhestir@ fandr.com; Froehling & Robertson, Inc., Greenville, SC Union High School was developing land adjacent to their existing facilities to pro-vide new baseball fields and related infra-structure, and the administration was con-cerned that the soil in the berm around the high school’s gun range might have lead contamination. The gun range had been present at the high school for twenty-five years.

Initial soil sampling was performed to confirm the levels of lead in the back-stop of the range and the contaminated soil vol-ume was delineated utilizing a Direct Push (Geoprobe) unit and an X-ray Fluorescence (XRF) sampling device which measures lead content in soil in real time. A review

of lead in soil regulatory compliance re-quirements was conducted and a site sam-pling plan was submitted to the Department of Health & Environmental Control (DHEC).

Once the contaminated soil volume was mapped, F&R professionals worked with a remedial contractor to develop and utilize a plan to treat the contaminated soil onsite — an approach that allowed our client to avoid hauling the contaminated soil to a hazardous waste landfill, and which al-lowed onsite reuse of the stabilized soil. This approach reduced the cleanup costs from $140,000 to $50,000.

Mapping of the Clemson Forest us-ing Digital Field Mapping Tech-niques Lefitz, Alex, alefitz@g.clemson.edu, and Scott Brame, Environmental Engineering and Earth Sciences, Clemson University, Clemson, SC Geologic mapping can be tedious and time consuming. To expedite the conversion of field data into a comprehensible geologic framework, digital field mapping tech-niques are being used to map the Clemson Experimental Forest. A ruggedized field-ready PDA, the Trimble Juno SB, is being used to allow digital mapping in the field. This product combines GIS and GPS capa-bilities in a compact, handheld device. The software program, ArcPad 10, is installed on the Trimble to enable real-time map-ping. ArcPad allows data collected in the field to be immediately inputted into a working geologic map. This method allows the mapper to constantly update their geo-logic map and integrate not just data, but their field impressions, into a framework

28

that serves as the basis of their geologic interpretation.

Currently, this approach is being used to investigate the basis for the Clemson Window as previously mapped by Griffin (1994). In this geologic feature, the under-lying Walhalla nappe is exposed by erosion of the overlying Six Mile thrust sheet. Ac-cording to Griffin, evidence for the win-dow is indicated by the transition from the dominate rock types of the Six Mile sheet (mainly a biotite gneiss – mica schist) to the hornblende gneiss of the Walhalla nappe. An earlier map of the Clemson quad by Brown and Cazeau (1963) did not show this feature. Preliminary mapping of the area by the Clemson Forest Mapping group did not find evidence for the Griffin interpretation. It is hoped that a digital mapping approach will help to decipher the motivation for Griffin’s version of the geo-logic framework.

Biological and Chemical Reduc-tion of Chlorinated Solvents by Combining Zero-Valent Iron and Emulsified Vegetable Oil Liskowitz, Mike, mjl@arstechnologies. com, and Robert L. Kelley, ARS Technol-ogies, Inc., New Brunswick, New Jersey A variety of in-situ reductive chemical and biological reaction can be induced in a con-taminated aquifer to remove chlorinated volatile organic compounds (cVOCs). Chemical reduction by amendments such as ZVI reactive iron powder have the ad-vantage of being able to treat high concen-trations of cVOCs while producing limited amount of intermediates, such as vinyl chloride (VC). Biological reduction by

amendments such as emulsified vegetable oil (EVO) have the advantage of being able to treat very low levels (10 ppb) of cVOCs. Combining amendments like ZVI and EVO can work synergistically by creating a re-ducing environment that thermodynamical-ly promotes biological reductive dechlorin-ation.

At an active facility in Union NJ, a strategy to remediate TCE and associated daughter products in a shallow aquifer was needed. Soils consisted of silty sand with clay stringers. The amount of amendment was limited by the lower effective porosity. A combination of SRS™ Emulsified Vege-table Oil and a Ferox™ ZVI Reactive Iron Powders was used. The treatment depth was from 12 -22 feet and target well RW-2 which had a baseline of 320 ppb TCE. The injections were performed in 10 direct push locations utilizing ARS tooling (packers/nozzles) resulting in the injection of 3,500 gallons of solution (ZVI slurry and EVO). Based on the area, the estimated loading around of the ZVI/EVO slurry 0.2 % w/w (soil/slurry). Following the injec-tions, the baseline TCE (320 ppb) dropped to 3.3 ppb with little to no accumulation of daughter products. Figure 1 shows where the pilot activity removed the higher con-centrated plume around RW-2. From this successful pilot, a full-scale application is currently being plan for the entire site.

29

Characterizing Water Content Trends in Saprolite Soils near Clemson, SC Lyles, MollyJane, mlyles@clemson.edu, and L.C. Murdoch, Department of Envi-ronmental Engineering and Earth Sciences, Clemson University, Clemson, South Caro-lina The redistribution of rainfall as either re-charge, interflow or evapotranspiration is a fundamental aspect of the water budget, and it has important implications to ecosys-tem assessment, aquifer management, agri-culture practices, and related topics. The objective of this study is to evaluate the feasibility of assessing changes in soil moisture with space and time in order to estimate rainfall redistribution. In early December four access tubes were installed into local saprolite soils at the Bull Test

Site in Pendleton, South Carolina. These permanent tubes, each a meter deep, allow data to be taken by a multi-depth capaci-tance probe called the PR2 Profile Probe, distributed through Delta T Devices. Throughout the months of January and February 2013, data were collected from each of the four probes two to three times a week at depths of 0.1m, 0.2m, 0.3m, 0.4m, 0.6m and 1.0m millimeters. These data were compiled into Microsoft Excel files and compared with data collected by the nearby Decagon Devices Microclimate Monitoring System. Trends show that, re-gardless of recent storm events, the water content steadily increases with depth to av-erage around 0.5 at 0.6 m and it decreases at greater depths. The water content in the upper 0.1 m of soil is relatively low, and it varies with rainfall. These results suggest that the water content in the relatively low density A horizon is variable during rain-

Figure 1: Pilot Area for the Combined Treatment with ZVI and EVO

30

fall and daily evapotranspiration. Water that infiltrates deeper is impeded by a de-crease in hydraulic conductivity in the B horizon at roughly 0.5 meter depth, and it water content varies more slowly than at shallower depth. Time-lapse 3D Imaging of a Lab Scale Forced Infiltration Experi-ment Mangel, Adam R., Stephen Moysey, An-drea Creighton, and Yuanhong Song, Environmental Engineering and Earth Sci-ence, Clemson University, Clemson ,SC A lab-scale forced infiltration experiment was run in a large wooden tank (4 m x 4 m x 2 m) to observe wetting patterns associat-ed with a propagating wetting front in the vadose zone. To observe these patterns in 3D, we used a 900 MHz bistatic ground-penetrating radar (GPR) system to collect data in both common offset and multi-offset configurations for three different irri-gation flux rates. With this information, we plan to extract information about water distribution within the soil column at multi-ple locations in the tank.

The positioning of the radar antennas was carried out using an automated gantry controlled by three stepper motors, allow-ing us to quickly and accurately position the antennas for data collection during the highly dynamic infiltration process. The tank is equipped with 16 individual drains to assess where water is draining from within the tank and filled with 0.60 m of medium-grained sand. For the duration of the experiment, water flowing out of the tank was measured at regular intervals and readings from buried moisture probes were logged every 10 seconds. For a given flux rate, we progressively scanned the survey

area in 2D at increasing offsets, starting at 0.17 m, increasing by 0.025 m, and ending at 1.17 m. This was carried out until the measured flux draining from the tank was near half of the flux being pumped into the tank, after which we collected a full 3D survey at a single offset over a 2 m x 1 m area.

Three flux rates were used during the experiment in order to observe both chang-es in bulk water content and wetting pat-terns as flux increased. At the first flux rate of 0.73 m/hr, significant changes in both the radar data and moisture probe data indicate a slow moving wetting front mov-ing through the sand. In particular, the GPR data shows a sloped interface for the wetting front at the time of the 3D data col-lection. This was confirmed with observa-tions during the experiment by the drainage of water from a single drain located at the edge of the irrigated area nearly 2 hours after the irrigation was turned on. Later responses from subsequent flux rates of 1.66 m/hr and 3.2 m/hr showed a similar behavior, although the hydrologic response took much less time as dramatic increases in the outflow flux were seen in under an hour from the increase in irrigation flux. Also, water was observed flowing from three other drains four hours after the ini-tial onset of irrigation.

Analyses of arrivals on the GPR data have a distinct advantage over the data from the embedded soil moisture probes. Due to the high correlation between wave velocity and water content, we can con-strain the water content at multiple depths and locations around the tank, constraining the hydrologic model of the tank much bet-ter than the stationary data collected by the moisture probes. Further work will focus on streamlining the data collection and analysis process by upgrading the radar system, analyzing data with neural net-

31

works, and developing a coupled inversion algorithm to develop an accurate hydro-logic model.

Computer Modeling In Hydrogeol-ogy: Where Did It Come From, How Has It Evolved, And Where Is It Going? Molz, Fred J., fredi@clemson.edu, Envi-ronmental Engineering and Earth Sciences, Clemson University, SC The beginnings of computer modeling in hydrogeology are found within the petrole-um industry, soil physics, and the water resources division of the U.S. Geological Survey. By the end of the 1950s, knowledge of numerical analysis was not wide spread, but computational demands of the existing techniques still exceeded the power of most computers. Computer capa-bility and availability accelerated greatly during the sixties, and two distinguished educator/researchers, Irwin Remson (USGS, Drexel University, Stanford Uni-versity) and Paul Witherspoon (University of California at Berkeley, Lawrence Berke-ley Lab) entered the field. By the end of the decade, the next generation of young scientists were applying computer model-ing to hydrogeology problems of increas-ing complexity. Many of the resulting problem-oriented programs, usually written in FORTRAN, served as the basis for the more general-purpose programs that fol-lowed, which included MODFLOW, MT3DMS, the TOUGH family of codes, T2VOC, FEMWATER, FEMWASTE and many others. Now, even more inclusive proprietary codes are in use such as COM-SOL MULTIPHYSICS and the MOD-FLOW-based integrated flow and transport code called MODHMS. Numerical analy-

sis is once again becoming a more special-ized field of applied mathematics and com-puter science, while many hydrogeologists are using the evolving general-purpose codes rather than writing new ones. So where do we go from here? I suspect that as computer models evolve to be more re-alistic and, therefore, more complex, we are going to begin to experience a phenom-enon known as “deterministic chaos”. The mathematical basis for deterministic chaos is well understood, although the full impli-cations are not. When it occurs, a comput-er program will become hyper-sensitive to initial conditions, which makes a unique future prediction impossible. One can only carefully measure a set of initial condi-tions, and then extrapolate forward a rela-tively short distance in time before unique-ness is lost - much like predicting the weather. This phenomenon will be dis-cussed, and I’ll explain how we might even benefit from its occurrence. System Design Enhancements of a Dual-phase Extraction System for the Cleanup of Heavy Fuel Oils Montoy, Jorge, jmontoy@sovcon.com, and Kevin Wheeler, Sovereign Consulting Inc., Robbinsville, NJ The remediation of separate-phase heavy fuel oil in soil and groundwater can be challenging, given the contaminant’s high viscosity and low volatility. Product re-covery is often performed using down-well skimmers; however, this approach may be inappropriate for projects with significant contaminant masses or projects with accel-erated cleanup schedules. An alternative to skimming is dual-phase extraction (DPE), which removes both oil/groundwater and soil vapors simultaneously. The applica-

32

tion of DPE as a remedial strategy at a large site in New Jersey contaminated by heavy (no. 6) fuel oil is presented with a special emphasis on design modifications that increased the system’s remediation efficacy. Using an adjustable drop tube with pitless adapters, special modifications were made to the slotted well screen at the end of each drop-tube to allow for im-proved flow balancing and control of water extraction rates. Because of the recovered product’s high viscosity and its tendency to emulsify, settling tanks with a gravity drain system are utilized in lieu of a traditional oil/water separator. Odor control on the tanks was accomplished through the use of small diameter tubing with needle valves attached to the extraction blower inlet tub-ing. Other design challenges included a large process flow at high and varied vacu-um (approximately 500 SCFM at 18” Hg), which was addressed by placing multiple rotary claw blowers in parallel rather than using liquid ring pumps, which do not per-form well under varied conditions. The improved control of the DPE system af-forded by these system design specifics is discussed and the efficacy of contaminant removal is shown with six months of per-formance data. Outlining the Advantages of Se-lecting Catalyzed Hydrogen Perox-ide or Activated Sodium Persulfate at Two Different Petroleum Hydro-carbon Sites Moody, Will, wmoody@geocleanse.com, Geo-Cleanse International, Inc., Matawan, NJ Many factors must be considered when evaluating a site and assessing potential in-

situ chemical oxidation (ISCO) approach-es. One of the fundamental decisions to be made is which oxidant should be utilized. Catalyzed hydrogen peroxide (CHP) and activated sodium persulfate (ASP) are common oxidant systems used for ISCO. When selecting the oxidant system for the remediation of a site, it is important to have a firm understanding of each oxidant and its’ ability to destroy the constituents of concern under various site-specific condi-tions. Some major factors that must be un-derstood are the chemistries involved with the reactions, the activation methods that may be utilized, the oxidant demand on a stoichiometric basis, site conditions that may affect obtaining the treatment goals, the cost of the applications, and the timeframe in which the project needs to be completed.

This presentation will provide a com-parison of two different petroleum hydro-carbon impacted sites where different re-medial ISCO applications utilizing ASP and CHP were implemented. The reasoning behind the selection of each oxidant will be examined, along with the overall conclu-sions and results for each site. The first site consists of low contaminant concentrations located at a shallow treatment interval, and the selected oxidant was ASP. CHP was selected for the second site, which dealt with a deeper treatment interval where the concentrations were high and LNAPL was present. The oxidant demand calculations, and the advantages and disadvantages for the utilization of each oxidant at the refer-enced sites will be discussed. After outlin-ing each site and the implemented treat-ment approach, a clarification will be given on how to select whether CHP or ASP would be more appropriate for various pe-troleum hydrocarbon contaminated sites.

33

Biological and Chemical Reduc-tion of Chlorinated Solvents by Pneumatic Fracturing and Injec-tion of Zero-Valent Iron in Sapro-lite Moskal, Eric , em@arstechnologies.com, ARS Technologies, Inc., New Brunswick, NJ; and Annie Lee, Stewart Abrams, Kenneth Tyson, and Steven Ciambru-schini, Langan Engineering & Environ-mental Services, Lawrenceville, NJ; and Daren Moss, Brixmor Property Group, New York, NY A 19-acre shopping center is impacted with chlorinated ethenes, primarily tetrachloroe-thene (PCE), from former dry cleaning op-erations. PCE has been observed at con-centrations up to 41,400 µg/L in the source area, with the majority of the mass in the saprolite and partially weathered rock over-lying the bedrock. The partially weathered bedrock, at depths from approximately 55 to 80 feet below ground surface (bgs), con-sist of sandy silt with rock fragments and exhibits a low hydraulic conductivity pre-viously measured as approximately 0.6 feet/day. Pneumatic fracturing and liquid-atomized injection of micro-scale zero-valent iron (ZVI) in the saprolitic and par-tially weathered bedrock zones was per-formed. The pneumatic fracturing created an interconnected fracture network for ZVI delivery in a dense formation that would have yielded very low conventional injec-tion flow rates. A ZVI dosage of 0.4% of soil mass by weight was used, as deter-mined from the treatability study. Based on the risk modeling, the highly impacted 20,000 square feet source area (PCE con-centrations greater than approximately 15,000 µg/L) was treated at depths ranging from 10 to 70 feet bgs to target both the

saprolite and partially weathered rock. Overall, 401,310 pounds (182 metric tons) of micro-scale ZVI was injected over 29 days concurrent with the building construc-tion activities. The project was completed successfully and the commercial building was constructed on schedule.

The post-injection monitoring results show significant reductions of PCE within the source area and directly downgradient area. The third quarter post-injection moni-toring results showed reductions of PCE within the partially weathered bedrock ranging from 96% at the upgradient portion of the treatment area to 99.7% (decrease from 20,200 to 56.8 µg/L) in the down-gradient portion of the treatment area. The oxidation reduction potential (ORP) has remained low through the third quarter, ranging from -163 to -416 mV in the source area. Most notably, although total chlorinated volatile organic compound (CVOC) concentrations are decreasing, the accumulation of daughter products is ob-served. It appears the reducing environ-ment created by the ZVI has stimulated that biological reductive dechlorination. Advanced Passive Soil Gas Sam-pling – Collection of High Resolu-tion Data to Effectively Guide Re-mediation Strategies O’Neill, Harry, harry.oneill@beacon-usa.com, Beacon Environmental Services, Inc., Forest Hill, MD and Michael Press-ley, ERM NC, Charlotte, NC Past operations at an industrial manufactur-ing facility in central South Carolina may have resulted in the release of solvent con-taminants. Facility operations where sol-vents, including TCE, PCE, DCE, 1,1,1-TCA, and vinyl chloride, were known or

34

suspected to have been used or stored were targeted through a high-resolution site characterization approach to identify if contamination was present and, if so, to define areas of highest concentrations and delineate the lateral extent.

ERM employed a minimally intrusive, passive soil gas (PSG) technology to define the nature and extent of chlorinated hydro-carbon contamination across the industrial facility. A sampling grid was established over the areas of concern (AOCs) with 25- to 50-feet between sample locations, total-ing 54 sample locations. Samplers were placed in holes advanced to a 14-inch depth, sealed, and left in the ground to ad-sorb organic compounds for approximately 14 days.

Following the exposure period, the samplers were shipped to Beacon Environ-mental, an accredited laboratory for the analysis of the soil gas samples following EPA Method 8260C (GC/MS). While the purpose of the investigation was to screen the site for contaminants to guide future sampling and remediation, the passive soil gas samples were analyzed using mass spectrometry to provide high quality data with greater sensitivity and accuracy than traditional screening methods.

The passive soil gas survey identified source areas of several chlorinated com-pounds, as well as 1,4-Dioxane. The data is being used to guide the design of the re-mediation system. A discussion will be presented on the findings as well as the QA/QC procedures of the PSG method both in the field and in the laboratory to produce high quality, high resolution data that identifies source areas and tracks groundwater plumes while employing a minimally invasive technique.

Legal Issues for the Professional Scientist Ormond, J. Charles Jr., Holler Dennis Corbett Ormond Plante & Garner, Colum-bia, SC Scientists, technologists and engineers of all disciplines are now and will in the fu-ture play an increasingly important role in both judicial and administrative outcomes as they work with attorneys in compliance audits and investigations, regulatory en-forcement actions and in litigation. Fur-ther, professional negligence issues will continue to affect the private practice of geology and engineering. Some knowledge and understanding of the basic principles of this area of the law is helpful to any scientist whether in private business or those with a government agency.

Technical persons working in a lawsuit or in anticipation of a lawsuit, when re-sponding to questions or inquiries by attor-neys or other experts, may develop docu-ments for a litigation team. In doing so, they will almost certainly encounter the concept of work product privilege for doc-uments and information relayed to an attor-ney. This concept is not absolute and is subject to varying interpretations. If the scientist is retained as an expert to render specific testimony only admissible by an expert witness, most documents will be discoverable and admissible, including drafts or data used to support the opinion. If in an advocacy position, once an opinion is determined, a technical agent or witness when preparing reports, statements or writ-ten opinions, should write the document from a position of advocacy for the posi-tion taken. However, written reports or investigations designed for in house use or for information purposes should be written

35

with all possible interpretations in mind and may be subject to statutory or attorney client privileges protecting documents from government agencies and sometimes even from opposing parties in discovery in a subsequent suit.

Even relatively simple scientific con-cepts and theories used in an expert opin-ion may be subject to judicial scrutiny prior to allowing such evidence in front of a fact finder. An expert geological witness can overcome this scrutiny by carefully demon-strating that the opinion to be rendered has met with procedural diligence and satisfied most if not all the factors set forth by the state and federal Supreme Court within the several years. Moreover, a geological ex-pert may the assist the attorney or advocate of any kind whether private or public in determining whether opposing experts may have failed to demonstrate such diligence.

Recent tort reform will apply to all pro-fessional negligence cases including allega-tions against scientists or engineers per-forming duties for clients or to third parties alleging negligence. Statutory provisions now require any Plaintiff, bringing an ac-tion against a professional and alleging professional negligence, to initially obtain a professional expert opinion in affidavit form. Such expert must be a comparable professional to the defendant and the expert must specifically testify as to the standard of care and its breach by the defendant.

Improved Solute Concentration Estimation using a Pattern Match-ing Approach to Capture Site-specific Plume Morphologies Oware, Erasmus K., and Stephen Moy-sey, Environmental Engineering and Earth Sciences, Clemson University, Clemson, SC; and Taufiquar Khan, Mathematical Sciences, Clemson University, Clemson, SC A common challenge frequently encoun-tered in hydrology is a non-invasive ap-proach for capturing site-specific continu-ous concentration profiles of the sub-surface. This research formulates a seam-less pattern matching algorithm, for recon-structing solute plumes. The methodology involves intrinsically capturing site-specific spatial geometric features into geo-logical analogs, via numerical simulation of multiple solute plumes constrained to a conceptual model of the actual site under investigation. Afterwards, a set of spatial patterns is constructed from the training images, by passing over each pixel with a window and collecting template scale pat-terns. The resulting spatial patterns are ran-domly pulled from the patterns library, which are then seamlessly matched to hon-or the observed data. The technique is a general sub-surface characterization strate-gy that can utilize different types of data for reconstructing sub-surface spatial fea-tures. Preliminary results based on bore-hole concentration data and on electrical resistivity measurements show that the strategy is able to accurately reconstruct true plume morphologies to a root mean square error (RMSE) of 48.78 mg/L and 0.21 for both concentration and log of con-ductivity data, respectively. In addition, peak spatial parameter values were estimat-

36

ed to be 1200 mg/L for the concentration data and -0.64 for the log conductivity da-ta, given their corresponding actual values of 1237 mg/L and -0.13, respectively. De-spite the preliminary encouraging perfor-mance of the algorithm, there are, however, some initial computational challenges that require further research for the full devel-opment of the strategy. Removing the ambiguity of geo-chemical analyses in groundwater using environmental molecular di-agnostics Peacock, Aaron D., APeacock@ haleyaldrich.com, Daniel McDonnell, and Mark Miesfeldt, Haley & Aldrich, Inc., Greenville, SC In situ biological treatment strategies are being utilized to address groundwater con-tamination at thousands of sites worldwide. Depending upon site characteristics, appli-cations include the coupling of aggressive approaches to treat source areas, followed with the addition of “biological process-enhancing” compounds. Less aggressive biological-only approaches include the ad-dition of oxygen, or a carbon source to stimulate naturally occurring oxidative or reductive (respectively) bioprocesses. Fi-nally, fully passive approaches such as monitored natural attenuation (MNA) tech-niques are increasingly being used at latter stages of remediation and to justify no fur-ther action or site closures.

Key to demonstrating effectiveness of biological treatment strategies is establish-ing cause and effect relationships, to prove that desired bioprocesses are either occur-ring now and will in the future. Under tra-ditional methods, a central component of such strategies is a comprehensive ground-

water monitoring program (particularly with MNA). In addition to assessing con-taminant concentrations and trends, the monitoring program typically measures concentrations and distributions of numer-ous geochemical parameters considered major indicators of current and potential biological activity in groundwater. These geochemical parameters include a range of electron acceptors, byproducts of various metabolic processes, and oxidation/reduction potential (ORP). Data from the geochemical measurements, in conjunction with contaminant trend data, are intended to help clarify subsurface conditions and to determine prevalent bioprocesses (aerobic versus anaerobic growth, etc.), and assess the effectiveness of the biological treat-ment strategy.

Over the years, we have been involved in assessing geochemical data to monitor in situ bioprocesses for a number of sites throughout the U.S. We consistently find that in practice, measurement of the re-quired parameters is often time consuming and costly, and difficulties with data inter-pretation often occur, including major in-consistencies with contaminant plume data. Difficulties with data interpretation can include natural spatial variability in distri-bution and concentrations of naturally oc-curring anions and cations, DO, and ORP, sampling method-induced variability (particularly with DO), and field instru-mentation errors (instrument and human error). Our experiences led us to conclude that, while measuring these parameters is theoretically a technically sound approach, the data are often inconsistent and/or con-flicting, and the insight is frequently mini-mal and incommensurate with the level of effort and costs involved. Most important-ly, with a geochemical only approach, it is often difficult or impossible to demonstrate convincingly that bioprocesses are occur-

37

ring, even when it is very likely that they are.

However, more useful and potentially cost-effective alternative methods are now emerging to assess in situ bioprocesses. These methods directly measure various biochemical constituents of the microbes themselves (i.e. “biomarkers”) or isotopes of contaminants, which indicate metabolic processes, and provide direct, relevant in-formation regarding the environment and the potential for contaminant degradation. Termed environmental molecular diagnos-tics (EMDs), these techniques can provide a more accurate and cost-effective assess-ment of in situ bioprocesses for sites under-going active bioremediation, MNA or other biological treatments.

EMDs are based on the principle that certain parameters of microbial biochemis-try indicate the conditions under which the microbes live. That is, microbes produce specialized, measurable, intercellular con-stituents (nucleic acids, proteins and en-zymes) involved in specific metabolic ac-tivities, which vary in response to the envi-ronment. The presence or relative quanti-ties of various constituents indicate specific metabolic activities, and provide direct evi-dence of environmental conditions under which the organisms are growing in situ. This information can show which biopro-cesses are occurring, and/or whether spe-cific conditions that favor degradation of a specific contaminant, or class of contami-nants, are present. However, since the analysis is of the organisms or the isotopic values of contaminants themselves, this approach can most times eliminate the am-biguity surrounding analysis of geochemis-try alone to assess bioprocesses in ground-water.

This talk will introduce several of the most popular EMD techniques for in situ remediation and present two case studies

where the use of EMDs directly impacted site management and strategy.

Chemical and Biological Reduc-tion in Vadose Zone Sediments Rossabi, Joseph, rossabi@redox-tech.com, Redox Tech, Cary, NC; Steve Markesic, Redox Tech, Downers Grove, IL; John Haselow, Redox Tech, Cary, NC; Greg Powers, Redox Tech, Aiken, SC; and Bob Wyrick, AECOM, Raleigh, NC Enhanced reductive dechlorination in va-dose zone soils is often rejected as a poten-tial strategy for remediation even before key parameters are known. The notion that vadose zone soils are dry rather than par-tially saturated is the classic glass half-empty rather than half-full stance. Some-times the rejection of enhanced reductive dechlorination strategies occurs even when data show natural reductive dechlorination is already occurring. We have developed and used techniques and products that have resulted in successful reductive dechlorina-tion remedies and discuss results.

Soil moisture content is generally con-sidered a primary limiting factor for suc-cessful remediation of chlorinated solvents using amendments either to encourage oxi-dative or reductive remediation. Nearly all of the commonly used oxidants react in the aqueous phase and the oxidant and contam-inant must be in contact for a reaction to occur. Similarly, contaminant must be able to contact the surface of zero valent iron (zvi) in order for chemical reduction to oc-cur on the surface of the iron. Finally, bac-teria can only multiply and metabolize in an aqueous medium and despite their abil-ity to improve the odds of contact with contaminant by chemotaxis, require aque-ous contiguity to move to contaminants by following a concentration gradient.

38

Often residual contamination (especially volatile organic contamination) in the vadose zone is found in fine grain rather than coarse grain materials. Volatile contaminants will be rapidly removed by diffusion, advective gas flow or both unless they are occluded by water or sorbed to soils. Fortunately fine grain materials gen-erally have a higher residual water satura-tion so although still part of the unsaturated zone, contaminants will generally be found in the more saturated part of the unsaturat-ed zone. There are several strategies to maintain or increase water saturation in the vadose zone to help facilitate remediation including adding fine grain or hygroscopic materials and amendments into the vadose zone soils. In addition to increasing and retaining water saturation, amendments are used to increase the rate of remediation such as adding zero valent iron for chemi-cal reduction, creating hydrogen, removing oxygen, and promoting conditions more conducive to biological reduction.

We have successfully applied amend-ments to vadose zone soils by both soil blending and direct push injection. ABC+ (zero valent iron and carbon substrate) was injected in the vadose zone at several gla-cial till sites in Illinois which achieved site closure. At an Atlantic Coastal Plain site in North Carolina, we compared chemical ox-idation to two carbon substrates, and zvi plus carbon substrate in a pilot scale test of soil blending in the vadose zone. Full scale soil blending with ABC+ was selected as the final soil remedy based on the results of the pilot scale tests and the regulatory tar-gets have been met for these soils.

Measuring Analytical Laboratory Performance: Establishing Basic Data Review standards Rosseter, Diane M., drosseter@ synterracorp.com, SynTerra Corporation Greenville, SC 29601 Analytical data generated from collection and analysis of environmental samples pro-vides the decision-making backbone for most environmental assessment activities. Once samples are collected and submitted to the laboratory for analysis, it is often mistakenly assumed that the overall quality of the analytical data produced is the re-sponsibility of the laboratory. As licensed professionals, geologists and engineers are required to sign and stamp their work, cer-tifying, and essentially taking responsibil-ity for, the quality of the information used to produce the document bearing their sig-nature. Although analytical laboratories generating data for compliance reporting purposes in most states are required to maintain certification by an appropriate regulatory authority, the term “certified” does not necessarily mean the data is guar-anteed to be accurate and error-free.

To meet market demands, analytical laboratories are production-oriented facili-ties capable of generating thousands of data points in a single day. As with any busi-ness in a competitive market, the necessity of high productivity to generate a profit can interfere with the good laboratory practices that result in high quality data. Most con-sumers of commercial laboratory services have experienced sloppy reporting, includ-ing erroneous results, elevated reporting limits, missed holding times, transcription errors, and carryover contamination. These errors often go unnoticed and are carried through the entire assessment, reporting,

39

and decision-making process. Systematic analytical data review en-

sures that anomalies or issues are identi-fied. Data review is performed to assess analytical results for precision, accuracy, completeness, and compliance with data quality or program objectives. Qualified data may be used for decision-making pur-poses if the impact the qualifications have on overall program or project objectives is understood. Reviewing and assessing data quality provides an added level of confi-dence in the reporting and application of environmental analytical data. Hysteretic Trapping and Relative Permeability of CO2 in Sandstone at Reservoir Conditions Ruprecht, Catherine, Ronald Falta, and Lawrence Murdoch, Environmental Engi-neering and Earth Sciences, Clemson Uni-versity, Clemson, SC; Sally Benson and Ronny Pini, Energy Resource Engineer-ing, Stanford University, Stanford, CA Residual trapping is a dominant mecha-nism of CO2 immobilization in saline aqui-fers during geologic sequestration. During injection, CO2 displaces formation water in a drainage process (water saturation de-crease). The CO2 plume flows buoyantly upward and laterally out along the sealing layer. Following injection, water displaces rising CO2 in an imbibition process (water saturation increase). This imbibition pro-cess leads to the disconnection of the CO2

plume into immobile blobs and ganglia. In this way, a trail of immobile CO2, known as the residual saturation, is trapped behind the plume as it migrates [Hunt et al. 1988, Juanes et al. 2006]. The residual saturation is a key parameter in relative permeability functions used to model multiphase

transport of injected CO2. As this study shows, the residually trapped CO2 satura-tion is not a set value but a hysteretic func-tion dependent on the maximum saturation reached in a given pore space before imbi-bition. In this study, we report results from an experimental investigation of hysteresis in residual trapping and relative permeabil-ity of CO2 in a CO2 /water system at 50ºC and 9 MPa in a Berea sandstone core.

Saturation data were collected using the steady state method in a horizontal core flooding apparatus with x-ray computed tomography. This method began with a wa-ter saturated Berea core, 10 cm in length and 5 cm in diameter. The core was brought to target storage conditions, repre-senting a formation approximately 900 m deep in the subsurface. Water and super-critical CO2 were simultaneously injected into the core at a total flow rate of 20 ml/min. Three cycles of drainage and imbibi-tion were completed by incrementally in-creasing and decreasing the fractional flow of CO2 to water while maintaining the total flow rate. The cycles were performed such that the turning point saturation (the maxi-mum saturation of CO2 prior to imbibition) was increased each cycle. Once uniform saturation and steady state were reached at each fractional flow rate, an x-ray CT scan was taken and the pressure drop across the core was recorded. These measurements were used to calculate the relative permea-bility at each data point.

Results show three sets of drainage and imbibition relative permeability curves for CO2. Drainage data match previous meas-urements taken under reservoir conditions from the same Berea core by Krevor et al. [2012]. Imbibition data show the trapped CO2 saturation increased for each increase in turning point saturation. A linear trap-ping model was determined describing the relationship between the residual CO2 satu-

40

ration to be approximately half of the turn-ing point saturation for each cycle. A hys-teretic Van Genuchten-Mualem relative permeability function incorporating the lin-ear trapping model is shown to fit experi-mental data. Results suggest it is essential to characterize the hysteretic trapping be-havior of CO2 in target storage formations in order to properly capture the nature of relative permeability behavior and more accurately predict the mobility of a CO2 plume over time.

Modeling the Effects of Residential Construction Activities on Stream Flow and Sediment Yield Santikari, Vijay P., vsantik@ clemson.edu, Environmental Engineering and Earth Sciences, Clemson University, Clemson, SC Sediment is the second most cause of im-pairment in assessed rivers and streams and construction activities are suspected to be responsible for about 13,000 miles of im-pairment in the USA. Still there are not enough distributed parameter modeling studies on simulating storm water volumes and sediment loads from catchments under-going construction activities. The objective here is to evaluate the applicability of ex-isting distributed parameter watershed models.

Hydrologic and sediment data were collected from several streams that drain small catchments (~1 km2) in Greenville County, South Carolina. These catchments have undergone varying degrees of active development and one catchment that did not undergo any development served as undisturbed reference. Analysis of storm events has already shown that the storm

water volumes and sediment yields from disturbed catchments were up to 2 to 3 magnitudes higher than those from the un-disturbed reference. SWAT (Soil and Wa-ter Assessment Tool), a semi-distributed parameter model and GSSHA (Gridded Surface Subsurface Hydrologic Analysis), a distributed parameter model were used to model the catchments. SWAT is largely an empirical model and does not take land use interactions into account. GSSHA is more process based and because of its fully dis-tributed nature, can account for land use interactions. A comparative study of these models and the results will be discussed.

Fate and Distribution of Arsenic in a Pilot-Scale Constructed Wetland Treatment System for Simulated Bangladesh Groundwater Schwindaman, Jeffrey P., and J.W. Cas-tle, Environmental Engineering and Earth Sciences, Clemson University, Clemson, SC; and J.H. Rodgers Jr., School of Agri-cultural, Forest, and Environmental Scienc-es, Clemson University, Clemson, SC Constructed wetland treatment systems (CWTSs) may offer an effective approach to treating arsenic-contaminated groundwa-ter in Bangladesh. The objectives of the current study were to (1) design and con-struct a pilot-scale CWTS to reduce the concentration of arsenic in a simulated Bangladesh groundwater from ~200 µg/L to < 10 µg/L, the USEPA maximum con-taminant level for arsenic in drinking wa-ter, (2) assess arsenic removal performance by determining removal extents, efficien-cies, and rates, and (3) evaluate biogeo-chemical removal pathways based on the fate and distribution of arsenic in the CWTS. Two treatment series were de-

41

signed to promote co-precipitation and sorption of arsenic with iron oxyhydrox-ides under oxidizing conditions, while two series were designed to promote precipita-tion of arsenic with sulfide under reducing conditions. An oxidizing and a reducing series were amended with 20 g per reactor of zero-valent iron (ZVI) every two weeks. Addition of ZVI significantly improved (α = 0.05) performance of both oxidizing and reducing series. The inflow concentration of arsenic was 160 ± 48 µg/L (mean and standard deviation). Arsenic removal per-formance was significantly greater (α = 0.05) in the oxidizing series amended with ZVI than in any other series, with removal extents, efficiencies, and rate coefficients ranging from 5-60 µg/L, 51-95 %, and 0.18-0.77 d-1, respectively. The majority of in-flow arsenic retained in the first reactor of each series partitioned into the sediment (87-93 %). The upper 6 cm of sediment accounted for 74-85 % of total sedi-ment-bound arsenic, whereas the remainder was measured at a depth below 6 cm. An increase in acid volatile sulfide (AVS) con-centration over time in the reducing series was attributed to dissimilatory sulfate re-duction. The greater increase in AVS con-centration in the reducing series amended with ZVI (541 mg/L) compared to the una-mended control (111 mg/L) was attributed to the ZVI amendment acting as an elec-tron donor for sulfate reduction. 7-13 % of retained inflow arsenic partitioned to wet-land plants (Typha latifolia). The roots and submerged shoots accounted for 78-96 % of total plant-bound arsenic, whereas the remainder was measured in the emergent shoots and tips. Results indicate that the design basis of a full-scale CWTS for the effective treatment of arsenic-contaminated water could incorporate features from this pilot-scale study including oxidizing condi-tions and amendment with ZVI.

Distributions of Fracture Form Suggested By Tiltmeter Data Slack, William W., wslack@frx-inc.com, FRx, Inc., Blue Ash, OH The hydraulic fracturing process opens new space within the target soil or bedrock. Media that had occupied that space is pushed laterally by the fracture faces. The surrounding soil / bedrock accommodates the displacement by deforming. The defor-mation can be measured at the ground sur-face with tiltmeters. Inversion of the tilt data provides an estimate of the underlying fracture form thereby answering the ques-tion of where the injected material resides. Data quality, formation heterogeneity, non-ideal fracture form, etc. frustrate these cal-culations. Often, vast amounts of data are collected and the resulting “best fit” of all data is presented. Alternatively, subsets of the data can be analyzed to generate a large collection of inversion results. The charac-teristic parameters of the several results can be presented as probability distributions or spectra of possible values. This perspec-tive can show that two or more values of a key parameter, such as fracture dip, may have equal validity in fitting the tiltmeter data, and that, furthermore, none of the multiple values is equal to the single value that is obtained when all data are consid-ered in one inversion. This approach offers the ability to reconcile tilt data with physi-cal observations such as cores. Characteristics of Elastic Analysis

Elastic deformation can be evaluated quantitatively, and it seems to occur typi-cally, as suggested by the fact that induced fractures close if not propped open. One- dimensional elastic behavior is known as Hooke’s Law – the simple, linear algebraic

42

equation between length and force that is used in grade-school science classes to characterize a spring. Three-dimensional elastic behavior uses higher level calculus. The equations were developed through a series of papers starting with Lord Kelvin in the 19th century. Work by Paul Davis and his students in the 1980’s is most ap-propriate for analysis of tilt data collected during the creation of shallow hydraulic fractures used in environmental work. In particular, Yang and Davis developed equations to describe surface deformation over a plane fracture and also provided computer codes to permit numerical analy-sis.

These equations describe the shallow dome that forms over a fracture that has the form of a thin rectangular prism or disk-shaped cylinder. Significantly, the dome is spread over an area greater than the plan of the fracture. While the sum (or integral) of vertical displacements across the surface will equal the volume of injected material, the vertical displacements observed at a specific location almost never can be equated to the fracture apertures directly beneath the observation. Thus a true depic-tion of the fracture form requires a robust inversion of tilt data collected at the ground surface.

Inversion analysis is frustrated by noise in the data and geological complexity. Me-chanical and electrical noise is induced by site operations and weather conditions. The layers of soil structure and variable topog-raphy violate the homogeneity and sym-metry assumptions underlying the equa-tions. Fortunately, electronic tiltmeters pro-vide the opportunity to collect voluminous data. A statistical approach should be used to extract the desired information about fracture form.

In the simplest case, eight parameters influence the deformation of the surface

overlying an ideal fracture of elliptical plan. Three parameters characterize the lo-cation: depth, offset from parent well along strike, and offset along dip. Three more describe the size: aperture, extent along strike, and extent along dip. The last two are dip and azimuth of dip. The eight pa-rameters can be estimated by eight pieces of data. Since each tiltmeter provides two data streams (north – south tilt and east – west tilt), four tiltmeters theoretically pro-vide enough information to characterize an ideal fracture. Data from additional tiltme-ters can be used to examine variation and reliability of the parameter estimates. This paper describes a method for considering the data generated by a set of fifteen tiltme-ters. Exploring Distributions of Parameter Esti-mates

The inversion analysis uses non-linear parameter estimation processes – essential-ly curve fitting to an extreme degree. The immediately obvious approach is to apply such analysis to the thirty data streams gen-erated by the fifteen tiltmeters. The result-ing estimated parameters are those that pro-vide the “best fit” of all thirty pieces of da-ta, in which “best fit” usually is assessed quantitatively as the minimal sum of resid-uals between the observed data and model projections. In this work, these results are referred to as the “Aggregate” results. The parameter estimation processes also can provide a presumed statistical variance or standard deviation for each estimate. These statistics are framed in the sense that the parameter estimates are members of normal distributions and that the “best fit” values are measures of the central values of the normal distributions.

Statistical distribution of estimated pa-rameters can also be determined by explor-ing the subsets of data available from fif-

43

teen tiltmeters. Consider, for the moment, what approach would be adopted if one of the tiltmeters were disrupted during the course of creating the fracture (actually an all too common situation.) In such a case, estimates would be made with fourteen tilt-meters. Depending upon which tiltmeter was eliminated, any of 15 sets of results would be obtained. Now consider applying the same practice to data produced by all fifteen tiltmeters functioning satisfactorily. The resulting fifteen sets of parameter esti-mates provide some insight as to the relia-bility of the findings.

If two tiltmeters are removed from the set of fifteen, 105 possible combinations can be explored to reveal ranges of esti-mates. Similarly, if only four tiltmeters are used out of the fifteen, 1365 different quad-ruplets can be selected. Since four tiltme-ters provide just enough information to re-late surface deformation to a fracture, the numerical inversion process converges quickly. The exercise of running all 1365 analyses is not overwhelming. The results provide a spectrum of values for each of the characteristic parameters.

These spectra can reveal distributions unlike the normal distributions assumed within the non-linear parameter estimation process. In the following example, we will focus upon the statistical mode of the spec-tra. The mode is the value that occurs most frequently in a distribution and need not coincide with the mean or the median. Case Study

In 2011 FRx created hydraulic fractures for the purpose of effecting in situ chemi-cal reduction at a contaminated site in the eastern United States. The particular target intervals were in the upper portions of a Triassic age formation comprising inter-bedded shale, siltstone, sandstone and con-glomerate. Locally, borings were advanced

through red/brown siltstone, red/brown sandstone, and gray sandstone.

Fractures were induced by first cutting six holes through 10 cm (4-inch) PVC cas-ing and into the surrounding rock. A 69 MPa (10,000 psi) water jet cut the holes. Holes were ~6 m diameter and expected to have extended up to 30 cm into the rock. The six holes were arranged radially in a horizontal star pattern. After cutting the holes, the interval was isolated with strad-dle packers and pressurized to induce nu-cleation of a hydraulic fracture. The hy-draulic fracture was propagated with a slur-ry of treatment material. The fracture was nucleated about 10 m feet below grade and was filled with 1.4 m3 of slurry.

Fifteen Applied Geomechanics Series 700 tiltmeters were arranged in a hexago-nal array around the injection well. The analog signals of the tiltmeters were con-verted to digital data by National Instru-ment 6000 Series devices. A proprietary data acquisition application drove the elec-tronics and recorded the data at 0.5 Hz.

The temporal trends of tilt were plotted to show the net change of tilt after the start of the fracture injection. Tilt developed at all measurement locations during the frac-turing event, reach maxima of several hun-dred micro radians just before or at the ter-mination of the event. This is typical be-havior. Pairs of tilt data from each tiltmeter allow calculation of the total tilt vector in terms of tilt magnitude and azimuth. The total tilt vectors at the conclusion of frac-turing (are very symmetric about the injec-tion well and suggest the formation of a horizontal fracture at depth. Indeed, coring after the creation of the fractures revealed the treatment material on plane with the nucleation intervals. (Slack et al., 2012)

A minor variation was introduced into the data inversion process. The three size parameters (among the eight descriptive

44

parameters to be determined) amount to the injected volume. By requiring the fracture to honor the known injected volume of 50.2 ft3, one of the size parameters could be removed from the analysis. We elected to eliminate aperture. Thus the inversion equations used the quotient of injected vol-ume and fracture area (��rdip rstrike) in lieu of aperture. This had minimal impact on the speed of the inversion process.

When data from all fifteen tiltmeters were used in the inversion analysis to esti-mate fracture form, the best fit for fracture dip was determined to be 0.51 radians, or nearly 30°. The remaining estimates were entirely consistent with expectations: depth = 10 m, offsets < 3 mm, and radii ~ 24 me-ter.

In contrast, the mode values of parame-ter distributions determined by considering the 1365 subsets of four tiltmeters were much more consistent with expectations and conformed to the coring observations. The mode value for dip was 0.012 radians, which is less than one degree. The spec-trum of dip possibilities does include sever-al cases for dip of ~0.1 radian (6°). A bump in the spectrum is noted at 0.5 radian. These alternatives occur because the inver-sion equations are extremely nonlinear and the tilt data set does have some asymmetry. In particular, the tilt magnitude at the loca-tion 12 m east is about 75% greater than that 12 m west. The seven spectra are shown in Figure 1.

Figure 2 shows how each of the 1365 estimates of ideal fracture form might ap-pear in the subsurface. In this figure, each case is drawn as a very light brown, orange-ish circle that has some transparency so that underlying circles can be viewed also. The case of the aggregate, “best estimate” parameters is drawn as the steeply dipping blue circle. The case using mode values is drawn as the nearly horizontal green circle.

The apparent brown circle of shallow dip is actually the intense density of the several cases that dip 0.1 radian. Likewise a lot of haze exists around the blue circle because of the population of cases with dip of ~0.5 radian. Conclusions The perspective suggested by inversion of subsets of data probably gives a more hon-est assessment of tilt data than statement of the aggregate best case alone, or the aggre-gate case with its statistical variation of coefficients. This approach recognizes the likelihood that multiple and distinctly dif-ferent values of characterization parameters may fit the observed data with equal validi-ty. In the absence of other confirming data, such as cores, the form of the fracture should be expected to be found somewhere within the haze depicted in Figure 2. References

Davis, P. M. (1983) "Surface Defor-mation Associated With a Dipping Hydro-fracture." Journal of Geophysical Research 88:B7 (5826-5834.)

Sir W. Thompson (Lord Kelvin) (1848) The Cambridge and Dublin Mathematical Journal.

Slack, W. W., B. C. Rosini, R. Srirangam and F. Lakhwala (2012) “Characterizing the Extent of Hydraulic Fractures Created In Partially Weathered Bedrock with EHC” 8th International Conf. On Remediation of Chlorinated and Recal-citrant Compounds, Monterey, CA.

Yang, X-M. and P. M. Davis (1986) “Deformation Due To A Rectangular Ten-sion Crack in an Elastic Half-Space.” Bul-letin Seismological Society of America 76:3 (86-881.)

45

Figure 2. Elliptical representation of each of 1365 inversion results. Each case is drawn as a very light circle. A solid ellipse of essentially zero dip represents the mode values of the parameters. A solid ellipse with dip of 30° (seen in edge view) corresponds to the “Aggregate” case.

Figure 1. Spectra of characteristic parameters generated by 1365 subsets of tilt data. Values of pa-rameters are spread along the x axis. Probability, or likelihood of occurrence, is indicated by the y axis. The vertical bars were drawn to represent the portion of inversion results that occur within the parameter range indicated by the width of the bar. The mode of each distribution is the parame-ter value with the highest bar.

46

Sediment Transport after Dam Re-moval on Twelve-Mile Creek, Norris, SC Waterhouse, Tyler C., twa-terh@g.clemson.edu, William M. Cham-lee, Jonathan A. Baldwin, Emily Thomp-son, Thomas Vaughn, and Murdoch, Lawrence, Environmental Engineering and Earth Sciences, Clemson University, Clem-son, SC Many dams are reaching the end of their operational life spans and some will be re-moved, releasing sediment that may affect the hydrology and aquatic ecosystems downstream. In some cases sediment re-leased following dam removal can be bene-ficial, for example, covering contaminated sediments in the downstream area. Cover-ing PCB-contaminated sediments in Lake Hartwell was the motivation for removing the Woodside I and Woodside II dams on Twelvemile Creek, near Norris, SC. The objective of this study is to characterize the resulting sediment accumulation and ero-sion after the Woodside II dam was re-moved during August 2011. The approach was to measure the volume of sediment in selected reaches of the stream as functions of time. After a base point was established, topographic surveys were conducted of the streambed and bank. A stadia rod, hand level, and measuring tape were used to sur-vey the sediment in the formerly impound-ed area. Six study sites were established downstream and were surveyed using a TOPCON RL-H3CL survey laser and a movable laser receiver mounted on a stadia rod. Surveys have been conducted every month to few months since June 2011. The elevation data from each survey was inte-grated using the trapezoid method and the subsequent volumes were subtracted from

the initial survey. The volume change was divided by the area of the streambed to es-timate the average change in the height of the bed, ∆h.

Results indicate that approximately 3x105 cubic meters of sediment (primarily well-sorted, fine to medium grained quartz sand) have been eroded from the former impoundment. The largest gain in sediment occurred at the first study site downstream from the former dam (0.6 km downstream) where the bed elevation increased by an average of 0.25m per month during the first 4 months after the dam was removed, the bed elevation began to fall after 8 months. Slight increases in bed elevation occurred further downstream, but the changes on average are less than 0.45m over the entire-ty of the study. Integrating the volume change indicates approximately 3x105 cu-bic meters of sediment have accumulated downstream from the former dam. These results suggest that most of the sediment that was once behind the dam is now in the stream and has not yet reached Lake Hart-well.

Ozone Sparging as a Soil/Groundwater Remediation Strate-gy at Large Scale Sites Wheeler, Kevin, kwheeler@sovcon.com , and Montoy, Jorge, Sovereign Consulting Inc., Robbinsville, NJ Ozone is a proven oxidizer for application of in-situ chemical oxidation. It has been utilized in the water/wastewater treatment industry for more than a century, and its effectiveness as a remediation process is becoming better understood. As a gaseous oxidant that is produced on-demand with an on-site generator, ozone can be better

suited than other aqueous oxidants for in-situ application for large, high contaminant mass sites. Gaseous ozone is typically eas-ier to apply to the subsurface through sparging, is more easily distributed in the subsurface, is less prone to short circuiting, and is not as affected by soil organic matter as an oxidant demand/sink. While ozone application requires more infrastructure than aqueous oxidants, such as permanent injection points, delivery tubing, and SVE application, this infrastructure allows ozone to be continuously applied until re-mediation goals are attained. This ap-proach makes ozone sparging more cost-effective than aqueous oxidants for sites with high contaminant mass or where mul-tiple aqueous injection events would be required. Ozone sparging as a remedy will be presented in the context of remedial ac-tion selection for two areas of a former chemical storage facility in southern New Jersey that is currently undergoing redevel-opment. In 2011-2012, an ozone sparge system was installed to treat soil and groundwater impacted primarily with chlo-robenzenes, carbon tetrachloride, and xy-lenes. The ozone sparge system includes 416 individually-controlled sparge points (104 borings with 4 nested points each), an output of 180 lbs/day of ozone, a total of 520 scfm of sparge air, and an SVE capaci-ty of 1500 scfm. Specific design consider-ations with respect to site geology, hydrol-ogy, contaminants, worker safety, system flexibility, green and sustainable remedia-tion, and present/future infrastructure will be discussed. Site operating and perfor-mance data from the first 6 months of oper-ation will be presented, including monitor-ing of groundwater geochemistry and con-taminant concentration sampling as measures of remedial progress.

Solvent DNAPL to MCL: Are We There Yet? Workman, Robert, rworkman@ crbgeo.net, CRB Geological & Environ-mental Services, Greenville, SC; and Fred-erick R. Baddour and Victor Rossinsky, CRB Geological & Environmental Ser-vices, Miami, FL When are we going to be done? When it comes to environmental remediation, this is the question that originates in the finance office, and usually does not end with the latest quarterly groundwater monitoring report. The question about reaching clo-sure calls for a responsible data review, especially where releases of solvents and other Dense Non-Aqueous Phase Liquids (DNAPLs) have occurred. Achieving sta-tus of No Further Action through compli-ance with Maximum Contaminant Limits (MCLs) is a desirable objective for unen-cumbered land use or sale value, and so interested parties continue to probe the question of whether remediation to MCLs at DNAPL impacted sites is feasible, cost prohibitive, or truly impossible.

In the 1990's the remediation industry took note that although billions were being spent to remediate solvent releases, few sites if any, were actually attaining compli-ance with MCLs. An EPA expert panel boomed over the remediation landscape in 2003 reporting that there were no identified sites where DNAPL source area reduction to MCLs had been achieved. As regula-tors, attorneys, consultant and clients took note of the implications of EPA’s DNAPL report, the idea grew that solvent remedia-tion to MCLs is not feasible.

One result of the discussion over the past 15-years is that alternative cleanup levels have become more prominent as site

48

remediation goals. During the same time, improved site assessment and remediation techniques have emerged, and a number of articles have documented cases in which DNAPL source areas were, in fact, treated to MCLs. For property owners and respon-sible parties, both of these are favorable developments and provide better options to achieve property remediation.

This presentation contributes to the on-going discussion within the environmental remediation community by reviewing site conditions at several sites managed by the authors where DNAPL source areas were assessed and then treated to MCLs. The factors which contributed to successful cleanup are presented, including release scenarios, contaminant characteristics, geo-chemical conditions, and applied remedia-tion methods. Using Soil pH and Ca/Mg Hard-ness to Map Bedrock in the Clem-son Experimental Forest Wylie, Peter, pwylie@g.clemson.edu, and Scott Brame, Environmental Engineering and Earth Sciences, Clemson University, Clemson, SC

Developing a coherent geologic frame-work of the Clemson Forest has been ham-pered by inconsistency in outcrop density and by a lack of readily identifiable pat-terns in the geologic formations. As a re-sult, an investigation was undertaken to examine the practicality of relating the bed-rock geology to its weathering products. Soils were collected from different parts of the Forest immediately adjacent to out-crops that represent the common rock types found in the Forest. The soil samples were analyzed for their major chemical compo-

nents. The primary goal was to be able to distinguish between soils derived from the two dominant rock types: biotite gneiss and amphibolite (hornblende gneiss).

The samples were analyzed for their chemical composition using two different methods. The first method utilized the soil testing service provided by the Clemson Agricultural Services Lab. This method offers a reliable option that was used as a check on the second method. The main drawback to this method is transporting large sample volumes from the field to a vehicle. While relatively affordable, the number of samples needed to fill in the gaps between outcrops can become prohib-itively expensive. Analysis of the soil chemistry using this method indicated that an analysis of just the calcium and magne-sium concentrations could be used as a more affordable and quicker test. The sec-ond method utilizes an off-the-shelf soil hardness test. This method offers an oppor-tunity to conduct tests in the field or to col-lect relatively small samples for analysis in the lab. In both methods, the soil samples were initially analyzed in the field using color based soil pH kits.

Clemson University, 140 Discovery Lane, Clemson, SC 29634 www.clemson.edu/geomuseum - 864-656-4600

2013 Exhibitors

Justin Mahan Mountain Environmental 1560 Pisgah Drive Canton, NC 28716 828-648-5556 jmahan@mountainenvironmental.com

Brian Shinall Fruits & Associates, Inc. 500 North Point Parkway Acworth, Georgia 30102 (770) 974-6999 bshinall@fruits-us.com www.fruits-us.com

Harry O'Neill Beacon Environmental Services, Inc. 2203A Commerce Road, Suite 1 Forest Hill, MD 21050 410-838-8780 harry.oneill@beacon-usa.com

Robert Kelley ARS Technologies 98 North Ward St. New Brunswick, NJ (732) 253-8131 bk@arstechnologies.com

Brian Strickland Geo Lab PO Box 1169 Dacula GA 30019 (770) 868-5407 brian_strickland@geolab.org

Michael Free Terra Systems, Inc. 130 Hickman Rd, Suite 1 Claymont, Delaware 19703-3579 (484) 889-2214 mfree@terrasystems.net

Kenneth Lipscomb AMS Inc. 3803 Grahams Port Lane Snellville, Georgia 30039 (706) 680-9015 kenl@ams-samplers.com

2013 Exhibitors

Patrick Hicks FMC Environmental Solutions 1735 Market Street Philadelphia, PA 19103 (919) 280-7962 patrick.hicks@fmc.com

Will Moody Geo-Cleanse International Inc. 400 State Route 34 Suite B Matawan, NJ 07747 (732) 970-6696 wmoody@geocleanse.com

Tara Esbeck Analytical Environmental Services 3785 Presidential Parkway Atlanta, GA 30340 (770) 457-8177 tesbeck@aesatlanta.com

Geoff Myers GARCO, Inc. 2242 Carl Drive Asheboro, NC (919) 451-3960 geoff@egarco.com

Michael Spacil Diamond V 2525 60th Ave SW Cedar Rapids, IA 52405 (864) 986-8441 mspacil@diamondv.com

Peter Byer SAEDACCO Inc. 9088 Northfield Drive Fort Mill, SC 29707 (803) 548-2180 pbyer@saedacco.com

Scott D. Carney GEL Geophysics, LLC P.O. Box 30712 Charleston, SC 29417 (843) 769-7379 sdc@gel.com

2013 Exhibitors

Adam Phillips Prism Laboratories, Inc. PO Box 240543, Charlotte, NC 28224 (704) 529 - 5274 aphillips@prismlabs.com www.prismlabs.com

Brian Chew Enviro - Equipment, Inc. 11180 Downs Rd., Pineville, NC 28134 (704) 588-7970 www.enviroequipment.com brianchew@enviroequipment.com

Jim Fineis Atlas Geo-Sampling 120 Olde Marietta Court, Marietta GA 30060 770-883-3372 jimfineis@atlas-geo.com www.atlas-geo.com

Barry Kroll ESC Lab Sciences 12065 Lebanon Rd., Mt. Juliet, TN 37122 704-614-2660 bkroll@esclabsciences.com

Brian Jeffers Pine Environmental Services, Inc. 4037 Darling Court, Suite D , Lilburn, GA 30047 (800) 842-1088 (770) 925-2855 bjeffers@pine-environmental.com

Michael L. Kilpatrick II Shealy Environmental Services, Inc. 106 Vantage Point Dr., West Columbia, SC 29172 (803) 791-9700 mkilpatrick@shealylab.com

H.W. Harter III Encotech/Carbon Service & Equipment PO Box 7337, West Columbia, SC 29171 (803) 447-0888 hwharter@carbonservice.net

Michelle Williams

XENCO Laboratories 6017 Financial Drive Norcross, GA 30071 (770) 449-9800 michelle.williams@xenco.com

Scott Pearce A & D Environmental Services PO Box 484, High Point, NC 27261 (800) 434-7750 (c): (336) 803-1783 spearce@adenviro.com www.adenviro.com/

John Horner LandProbe, LLC 6004 Ponders Court , Greenville, SC 29615 (864) 527-9324 www.landprobe.com

Allison Cantrell Pace Analytical 9800 Kincey Ave., Suite 100, Huntersville, NC 28078 (864) 508-4809 allison.cantrell@pacelabs.com

Alan Hewett Rogers & Callcott Envionmental P.O. Box 5655, Greenville, SC 29606 (864) 232-1556 alan.hewett@rogersandcallcott.com www.rogersandcallcott.com

Todd Romero KB Labs, Inc. 6821 SW Archer Rd., Gainesville, FL 32608 (352) 472-5830 toddr@kbmobilelabs.com www.kbmobilelabs.com

Doug Knight FRx, Inc. 400 Artillery Rd., Greenville, SC 29687 (864) 356-8424 doug@frx-inc.com

Bill Brecher EON Products 3230 Industrial Way S.W., Suite B, Snellville, GA 30039 (800) 474-2490 bill@eonpro.com www.eonpro.com

Jim Hays ENCO Laboratories, Inc. 102-A Woodwinds Industrial Ct. , Cary, NC 27511 (704) 408-8129 jhays@encolabs.com

2013 Exhibitors

2013 Sponsors

MarkLassiter,PresidentAEDrillingServices,LLC

TwoUnitedWayGreenville,SC29607(864)288‐1986

mlassiter@aedrilling.com

SteveGodfrey,PresidentGodfreyandAssociates,

POBox863Blythewood,SC29016

(803)333‐9911steve@godfreysite.com

DaveandTracyCampbellCampbellGeosciences,Inc.

15LeisureLaneWeavervilleNC28787

(828)484‐9980dhcampbell@bellsouth.netthcampell@bellsouth.net

GeorgeY.MaaloufRogers&CallcottEngineers

POBox5655GreenvilleSC29606(864)232‐1556

george.maalouf@rogersandcallcott.com

JohnHaselowJoeRossabiRedoxTech

200QuadeDriveCary,NC27513‐7402(919)678‐0140

jhaselow@redox-tech.com

JoeMcMurray,PresidentBlueRidgeEnvironmental

Services,Inc.2315KingsRd.Ext.Shelby,NC28152(704)482‐2111

Joem@blueridge‐esi.com

AllisonCantrellPaceAnalytical

9800KinceyAve.,Suite100Huntersville,NC28078

(864)508‐4809allison.cantrell@pacelabs.com

RussMiller,V.P.NachmanNorwood

andParrott1116S.MainStreetGreenville,SC29601(864)467‐9800

russ.miller@nnpwealth.com

ShaunMalinHRPAssociates,Inc.

1327MillerRoad,SuiteDGreenville,SC29607

864‐561‐5007shaun.malin@

hrpassociates.com

DrewBairdRegenesis

123RidgecresetDriveGreenville,SC29609(864)240‐9181

dbaird@regenesis.comwww.regenesis.com

EnvironmentalEngineeringandEarthSciences

GreggJonesCardnoENTRIX

3905CrescentParkDriveRiverview,FL33578(813)664‐4500

gregg.jones@cardno.com