A Proposed Geochemical Barrier to Reduce Phosphorus Loading to a Kettle Hole Pond

Jonathan G. Blount Ph.D, CH2M Hill, 318C East Inner Road, Otis-ANG Base, MA. 02542, Tel: 508-968-4670 x 5609, Email:  jblount@ch2m.com
Jon Davis P.E., Air Force Center for Environmental Excellence, HQ AFCEE MMR, 322 East Inner Road, Otis-ANG Base, MA. 02542, Tel: 508-968-4670 x 4952, Email:  jon.davis@brooks.af.mil

Ashumet Pond is a 215-acre kettle hole pond near the Massachusetts Military Reservation (MMR) on Cape Cod. This pond is fed primarily by groundwater and it has no surface water outlet.  A phosphorus-rich groundwater plume that originated at the former MMR sewage treatment plant (STP) is discharging to Ashumet Pond. Most of the phosphorus discharge is occurring through a small near-shore section of the pond bottom that is approximately 300 feet long and extends 80 feet out into the pond. Elevated levels of phosphorus (up to 3 mg/L) are expected to discharge through this section of the pond for decades. 

Tests indicate that phosphorus is the limiting nutrient for algae growth in Ashumet Pond.  Historical data from previous ecological investigations indicate that phosphorus concentrations and algae content in the pond have substantially increased over the last 30 years. These changes in the pond are thought to primarily reflect the cumulative impacts of  phosphorus loading by the STP plume. The development of more extensive and frequent nuisance algae blooms are expected if phosphorus loading is not controlled.  Consequently, AFCEE proposes to install a geochemical barrier along the plume discharge area in the pond. The barrier will consist of a mixture of quartz sand, native sediment and Zero Valence Iron  (ZVI). Upon exposure to groundwater and to shallow surface water, the ZVI will slowly oxidize to form ferric hydroxide, a compound that will sorb phosphorus from the plume, thereby reducing the phosphorus load to the pond.  This approach is appropriate in aerobic pond or lake environments containing sediment with low levels of natural iron.  The target zone in Ashumet Pond has these characteristics.

DNAPL Remediation Combining Thermal Extraction and Reductive Dechlorination

Rob Bogert, P.E., BEM Systems, Inc., 930 Woodocock Road, Suite 101, Orlando, FL, Tel: 407-894-9900, Fax: 407-894-1089, Email: rbogert@bemsys.com
Harlan Faircloth, P.E., BEM Systems, Inc., 930 Woodocock Road, Suite 101, Orlando, FL, Tel: 407-894-9900, Fax: 407-894-1089, Email: hfaircloth@bemsys.com
Phil LaMori, Ph.D., BEM Systems, Inc., 930 Woodocock Road, Suite 101, Orlando, FL, Tel: 407-894-9900, Fax: 407-894-1089, Email: plamori@bemsys.com
Mark Kershner, 45 CES/CEVR, 1224 Jupiter Street, Patrick AFB, FL 32925, Tel: 321-853-0964, Fax: 321-853-5435, Email: mark.kershner@patrick.af.mil

The ability to effectively access pore space and overcome obstacles impeding successful remediation of dense non-aqueous phase liquid (DNAPL) sites has been overcome by applying a hybrid of technologies. An innovative remediation approach combining thermal treatment with reductive dechlorination in order to increase mass removal and lower remediation costs has been demonstrated with promising results. This approach involves the use of large-diameter auger in-situ soil mixing equipment to deliver a mixture of steam and hot air to the source zone. The mixing increases the contact of the volatile organic compounds (VOCs) with the steam/hot-air and accelerates contaminant removal. To increase VOC removal efficiency and to reduce the soil mixing cost, zero-valent iron (ZVI) is added following steam injection.

A full-scale field demonstration was completed in January 2003 at Cape Canaveral Air Force Station to verify the efficacy of this technology to remove trichloroethene (TCE) and 1,2-trichloro-1,2,2-trifluorethane (Freon 113). Thirty-two test cells, 1300 cubic yards of soil, were treated from a depth of 20 to 55 feet below land surface. TCE concentrations were detected as high as 1,100 milligrams per kilogram (mg/kg) in soil and 510,000 micrograms per liter (µg/L) in groundwater during baseline sampling. Freon 113 concentrations as high as 12,000 mg/kg in soil and 350,000 µg/L in groundwater were also observed. Thermal treatment removed 60 to 90 percent of the initial VOC contamination after 60 to 70 minutes of mixing. ZVI addition increased these removal rates to 90 to 99 percent. Based upon the demonstrated results, full-scale remediation of the 42,000 cubic yard source zone is scheduled for spring 2004. It is anticipated that as a result of this source reduction remediation, the site will achieve cleanup target levels for the extensive dissolved groundwater plume in less than 60 years as compared to several hundred years anticipated without source-treatment.

Natural Attenuation and Pollutant Mixture Complexities

Maryann Burke, Groundwater Protection and Restoration Group,The University of Sheffield,Sir Frederick Mappin Building, Mappin Street, Sheffield, U.K. S1 3JD, Tel: +44 (0)114 225746, Fax: +44 (0)114 2225700, Email: Maryann.Burke@sheffield .ac.uk
Steve Thornton, Groundwater Protection and Restoration Group, The University of Sheffield, Sir Frederick Mappin Building, Mappin Street, Sheffield, U.K. S1 3JD, Tel: +44 (0)114 2225744, Fax: +44 (0)114 2225700, Email: s.f.thornton@sheffield.ac.uk
Steven Banwart, Groundwater Protection and Restoration Group, The University of Sheffield,  Sir Frederick Mappin Building, Mappin Street, Sheffield, U.K. S1 3JD, Tel: +44 (0)114 2225742, Fax: +44(0)114 2225700, Email: s.a.banwart@sheffield.ac.uk
Hugh Potter, Science Group: Air Land & Water, Environment Agency, Olton Court, 10 Warwick Road, Olton, Solihull, West Midlands, U.K. B92 7HX, Tel: +44 (0)121 7084279, Fax: +44 (0)121 7084637, Email: hugh.potter@environment-agency.gov.uk. 

The Natural Attenuation (NA) of individual contaminants has been significantly studied, providing regulators and industry with an understanding of their behaviour and fate in the environment.  However where complex contaminant mixtures are present the behaviour of these chemicals significantly change as plumes exhibit potentially complex interactions, both chemically and with indigenous microbial populations, and are thus less predictable.  Microbial populations interact in a variety of ways, for example synergism or even competition between the populations can occur, resulting in differing or interconnecting metabolic pathways, affecting the degradation rates of contaminants (Chapelle, 2001) , however knowledge is limited.

A project has been undertaken in order to gain a clearer and more concise understanding of the behaviour of contaminant interactions during biodegradation.  The aims of this project include:

• The development of a conceptual model to predict the reactive transport of complex contaminant mixtures in different geological materials,

• The determination of the degradation potential for individual contaminants in mixtures under different conditions

• The quantification of degradation rates for individual contaminants in mixtures and in different geological environments.

Experiments have been designed to evaluate the behaviour of individual priority pollutants, in order to then compare these compounds in more complex representative mixtures.  Differing geological media and associated indigenous populations, will also be chosen from a selection of field sites in order to better understand the effects of transport and the geochemical matrix on attenuation. Finally, mathematical modelling of reactive transport processes will be scaled up to assess the implications of the natural attenuation of contaminant mixtures at field sites.

It is anticipated that the achievement of the project will be a conceptual model of the interactions of complex contaminant mixtures with subsurface media, which can then be used in order to construct reliable predictions and guide a quantitative understanding of the processes that control NA in these mixtures for fate and transport modelling.

Novel Technology of Producing Nanoscale Iron for Groundwater Nitrate Removal

S. S. Chen, Ph.D, Assistant Professor, Institute of Environmental Planning and Management, National Taipei University of Technology, No.1, Sec. 3, Chung-Hsiao E. Rd., Taipei 106, Taiwan, Email: f10919@ntut.edu.tw 

Treatment of nitrate contaminants by zero-valent iron (ZVI) represents one of the latest innovative technologies for environmental remediation.  This research uses nanoscale ZVI for transformation of nitrate for their advantages of higher surface area and reactivity.  The nanoscale iron particles, with a diameter in the range of 1 to 100 nm, were synthesized in the laboratory.  Two methods of producing nanoscale iron particles are used to use in this research.  One is chemical method, which is using strong reducing agent to reduce ferric ion in the solution.  This method has been appeared in many literatures.  The other method is an electro-chemical method, which is the method invented by our research group and has not been seen in any literature. 

The results show, the nanoscale iron particles with a diameter in the range of 1 to 20 nm, which were tested by TEM, were successfully synthesized in the laboratory using electro-chemical method and chemical method.  In order to reduce the coalescence of the nanoscale iron, surfactants were needed to use.  Three types of surfactants were selected, including one anionic and two cationic surfactants.  The cationic surfactants, Cetylpridinium chloride (CPC), were more successful for dispersing out the particles to achieve higher ZVI surface area.  The optimum concentration 100 mg/L for the CPC dose was obtained

Comparing to the lab grade ZVI, nanoscale ZVI achieves higher removal efficiency in this study.  Nitrate removal under these experimental conditions complied with the pseudo-first order reactions.  Moreover, mass balance of the nitrogen species was shown only 60 % of the nitrate was converted to ammonia and nitrite.  It appeared that some of the nitrate was converted to nitrogen gas and the result is similar to the finding in some literatures.  The surface characteristics of the nanoscale iron after reacting with nitrate was investigated by ESCA and Fe₂O₃ was found on the iron particle surface, therefore, chemical equations can be proposed from the analytical results. 

An Overview of the Hydraulic Testing of the Final Fuel Spill-1 Remedial System Design at Massachusetts Military Reservation 

Ronald J. Citterman, CH2M Hill, 318 E. Inner Road, Otis ANGB, MA 02542, Tel: 508-968-4670 x5631, Fax: 508-968-4490, Email: Ron.Citterman@ch2m.com
John Glass, CH2M Hill, 1321 Park Center Road, Suite 600, Herndon, VA 20171,    Tel: 703-471-1441, Fax: 703-471-1508, Email: John.Glass@ch2m.com
Frank Lewis, CH2M Hill, 100 Inverness Terrace East, Englewood, CO 80112, Tel: 303-771-0900, Fax: 303-771-0900, Email: Frank.Lewis@ch2m.com
Jason Dalrymple, CH2M Hill, 318 E. Inner Road, Otis ANGB, MA 02542, Tel: 508-968-4670 x3010, Fax: 508-968-4490, Email: Jason.Dalrymple@ch2m.com
Paul Clement,CH2M Hill, 6001 Indian School Road N.E., Suite 350, Albuquerque, NM 87110, Tel: 505-884-5600, Fax: 505-883-7507, Email: Paul.Clement@ch2m.com
John Schoolfield, Air Force Center for Environmental Excellence, 322 E. Inner Road, Otis ANGB, MA 02542, Tel: 508-968-4670 x5601, Fax: 508-968-4673, Email: John.Schoolfield@brooks.af.mil

As a result of historic fuel spills dating back to the 1950s at the Massachusetts Military Reservation (MMR), a plume of ethylene dibromide (EDB)-contaminated groundwater extends over a mile in length southeast of MMR.  This plume, designated Fuel Spill-1 (FS-1), is detached from its source area and is currently migrating in a southerly direction terminating at the Quashnet River and surrounding cranberry bogs.  The flow of the Quashnet River increases two to three times as a direct result of groundwater discharge to the river and surrounding bog ditches.  Groundwater fate and transport modeling was used in the design of groundwater remedial system for the FS-1 plume.  Subsequent hydraulic testing of the remedial system has been performed to verify the effectiveness of the system design at meeting the remedial objectives.  During hydraulic testing, changes in the groundwater and surface water levels in response to various pumping stresses are monitored.  The resulting data provide insights regarding aquifer hydraulic properties, the spatial influence of the remedial pumping, and the nature of groundwater and surface water interactions.  The testing data are also used in conjunction with the groundwater fate and transport model to delineate the capture zones of the remedial system’s extraction wells, and to compare actual conditions with the predicted conditions of the original wellfield design.  Additionally, the hydraulic data are used to optimize the operation of the remedial system and the effectiveness and efficiency of the hydraulic and chemical monitoring network.  In this way, the groundwater restoration timeframe is minimized and potential impacts to local ecosystems (i.e., excessive drawdown of groundwater discharging to wetlands and vernal pools) are eliminated.

Methodology for Integrating Direct Sensing Tools With In-Situ Remediation Injection Technology to Facilitate Effective Treatment of Groundwater

Eliot Cooper, MS, University of Illinois, Vironex, Inc., 15267 W. Ellsworth Place, Golden, CO 80401, Tel: 303-277-9773, Fax: 303-277-9783, Email: ecooper@vironex.com
Todd Hanna, Vironex, Inc., 1225 East Mc Fadden Ave, Santa Ana, CA 92705, Tel: 714-647-6290, Fax: 714-647-6291, Email: thanna@vironex.com
Frank Stolfi,  Vironex, Inc., 1225 East Mc Fadden Ave, Santa Ana, CA 92705, Tel: 714-647-6290, Fax: 714-647-6291, Email: fstolfi@vironex.com  

The effectiveness of in-situ groundwater remediation technologies is a function of the delivery of reagents into direct contact with contaminants located in the dissolved, desorbed and NAPL phases. Many in-situ remediation projects move into full-scale without a good understanding of the radius of influence and distribution of reagents that can be achieved.

In order to deliver reagents effectively, the location of contaminant mass in relation to lithology must be determined. The membrane interface probe (MIP) is a direct push applied sensing tool that simultaneously measures soil conductivity and volatile organic compounds. Once contaminant mass has been identified, a reagent delivery strategy is developed to maximize reagent distribution, radius of influence, and injection rates, as well as to optimize project costs.

Delivery of reagents into the saturated zones is accomplished through direct push technology or injection wells. Injection is facilitated through a wide range of injection pumps, technologies, and delivery techniques. Distribution of reagents, radius of influence, and injection rates are directly impacted by the hydraulic conductivity and heterogeneity of the target interval.

Vironex will present a new methodology that utilizes site characterization data obtained with the MIP and integrates this soil conductivity and contaminant mass information into injection strategies, delivery techniques, and equipment selection for a wide range of chemical oxidation and bioremediation reagents, contaminants and site subsurface conditions.  

Pilot Engineered Wetland for Treatment of Dilute Waste Streams

M. Talaat Balba, Ph.D., Darlene Coons, Sophia Dore, Ph.D., Alan Weston, Ph.D., CRA, Inc., 2055 Niagara Falls Blvd., Suite 3, Niagara Falls, NY  14304, Tel:  716-297-6150, Fax:  716-297-2265

Engineered wetlands are a cost-effective innovative passive technology that can be applied for the treatment of a range of wastewater streams, including stormwater runoff, process wastewaters, groundwater, and landfill leachate.  Captured organic contaminants can be degraded by the wetland microbial population; metal contaminants can adsorbed on the wetland soils or converted to insoluble salts.  Wetland ponds also store runoff and rainfall, reduce flooding and soil erosion, and purify water by filtering wastes, sediments, and toxic compounds.  CRA has designed and is currently operating a pilot engineered wetland system to determine its effectiveness in treating dilute waste streams including leachate, stormwater, and sludge.  The results will be used to develop design and cost data for a full–scale treatment system.  The system consists of surface and subsurface flow cells designed to operate in either a parallel or series configurations; each cell is approximately 5 feet in width and 15 feet in length (two Surface Flow Cells, A and B, and one Subsurface Flow Cell, C).  The elevation of the wetland cells was designed to allow the whole system to operate by gravity flow.  The treated effluent is collected and gravity discharged to process sewer.  The available results indicate that wetland system is efficient in reducing the levels of biological oxygen demand (BOD), volatile and semi-volatile organic compounds, and organic acids to non-detect levels.  Specific conductivity, salinity, and TDS have also been substantially reduced by the wetland treatment.  The wetlands continue to be operated so that the maximum loading rates of the wastewater streams and the sludge waste can be determined.  In addition, the potential long-term concerns such as air emissions, vegetation stress, the effects of cold weather, and sediment accumulation, are being examined.  The presentation will discuss the performance of the wetland treatment system in detail.

White Karbon Filtration Media as an Alternative to Granulated Activated Carbon (GAC)

Baxter R. Duffy, Environmental H2O, 36 Lincoln Road, Kinnelon, NJ 07405, Tel: 973-492-1645, Fax: 973-492-1689, Email: bduffy@environmentalh2o.com
Craig A. Sandefur, Environmental H2O, 5900 Katella Avenue, Cypress, CA 90630, Tel:  562-795-7598, Fax: 562.795.7597, Email: csandefur@environmentalh2o.com
Donald L. Ochs, Environmental H2O, 5 Erlington Drive, Cinnaminson, NJ 08077, Tel:  609-410-6237, Fax: 856-786-1758, Email: dochs@environmentalh2o.com

The White Karbon family of Filtration Medias is complimentary set of materials designed to remove a variety of contaminants from groundwater. The White Karbon Family is composed of four distinct media that remove hydrocarbons, anions, cations and VOC’s.

White Karbon relies on chemisorption, ion exchange and molecular sieve technologies to remove specific contaminants from water. Typically, the White Karbon Medias remove a significantly larger contaminant mass, per unit volume of filtration media than GAC. For example, White Karbon WK25.5 typically absorbs between 7 and 20 times more hydrocarbon than GAC, and since its density (specific gravity) approaches 1 as opposed to 0.5 for GAC, significantly less material is needed to accomplish the same removal rates.  Additionally, it is more capable of “single pass” groundwater treatment with different contaminants in mixed phases.  Field trials of WK25.5 have shown up to 98% removal of all emulsified and dissolved oils in a single pass.

WK25.5 is designed to remove petroleum hydrocarbons, including highly emulsified oils.  White Karbon WK40 is designed for removal of positively charged metals such as copper, trivalent chrome and mercury II, WK40C is designed for removal of negatively charged metal such as hexavalent chrome, arsenic V and mercury II and WK45 is designed for removal of chlorinated compounds, ethers and alcohols. 

WK25.5 and WK45 can be used as a substitute for GAC in most groundwater treatment systems. These media can be batched within the same vessel or separately and are capable of adsorbing VOC’s hydrocarbons and metals in a single pass. Because of its contact time efficiency and subsequent reduced size requirements, EH2O has created a novel mass reduction application using WK45 and. Additionally, during initial field demonstrations, WK45 has been regenerated up to 20 times.  Regeneration results in harmless reaction products including CO₂, H₂O and chloride if chlorinated solvents were recovered.

Cyclodextrin Enhanced Remediation at Patrick Air Force Base, Florida

Harlan Faircloth, BEM Systems, Inc., 930 Woodocock Road, Suite 101, Orlando, FL, Tel: 407-894-9900, Fax: 407-894-1089, Email: hfaircloth@bemsys.com
Rob Bogert, P.E., BEM Systems, Inc., 930 Woodocock Road, Suite 101, Orlando, FL, Tel: 407-894-9900, Fax: 407-894-1089, Email: rbogert@bemsys.com
Michael Annable, Ph.D., University of Florida, Environmental Engineering Sciences, 217 AP Black Hall, Gainesville, FL, Tel: 352-392-3294, Fax: 352-392-3076, Email: annable@ufl.edu
Mark Kershner, 45 CES/CEVR, 1224 Jupiter Street, Patrick AFB, FL 32925, Tel: 321-853-0964, Fax: 321-853-5435, Email: mark.kershner@patrick.af.mil
Dean Goodin, Ph.D., Shaw Group, Inc., 415 Citrus Tower Blvd., Clermont, FL 34711, Tel: 352-394-8601, Email: dean.goodin@shawgrp.com

Aggressive approaches to dense-non-aqueous phase liquid (DNAPL) remediation may present a significant interruption to daily operations at active military installations. The use of cyclodextrin has been identified as a low maintenance method to treat DNAPL in-situ, thus avoiding problems associated with more complicated remediation systems. Cyclodextrin is used to increase the solubility of chlorinated volatile organic compounds (VOCs), such as trichloroethene (TCE), in groundwater and subsequently stimulate biological degradation. Moreover, cyclodextrin may serve as a co-metabolite further enhancing bioremediation. Currently this technology is being implemented on a pilot-scale basis at OT-30 in the industrial area of Patrick Air Force Base, Florida.

Cyclodextrin was selected over other enhanced bio-remediation technologies at OT-30 based upon the combination of adding an electron donor while enhancing solubility. Cyclodextrin is a non-reducing polycyclic maltooligosaccharide-based molecule. It is a mild co-solvent and is less likely to mobilize DNAPL than more aggressive co-solvents such as ethanol. Use of cyclodextrin as a co-solvent has been proven to be effective on low polarity VOCs in bench scale analysis and in previous field implementations.

Cyclodextrin was gravity fed into 11 wells within the contaminated zone during two injection events in July and August 2003. The injection zone ranges from 33 to 38 feet below land surface. Baseline and post-injection samples were collected from area wells to evaluate pilot test performance. Mass flux was monitored at four locations down gradient of the source zone. An initial increase in mass flux and TCE concentration downgradient from the injection zone is anticipated based upon enhanced solubility. The dissolved TCE should be more available for reductive dechlorination, and a decrease in concentration should be observed with time. Results from this study will prove that cyclodextrin is effective at treating DNAPL contaminated groundwater at OT-30 and other areas where more aggressive technologies would be undesirable.

In-situ Flushing Selective Phase Transfer Technology (SPTT^TM) Cost Effective Soil & Groundwater NAPL Remediation Including NAPL and Chlorinated Solvents

George A. Ivey, B.Sc., CES, CESA, Senior Environmental Specialist, Ivey International Inc., 26 Berkeley Place, Newington CT 06111, Tel: 800-246-2744, Email: budivey@island.net

Selective Phase Transfer Technology (SPTT) involves micro-encapsulation using four mixtures and two processes (In-situ & ex-situ), in the remediation of NAPL contaminated sites.  The LNAPL and or DNAPL molecules undergo a phase transfer as micelle encapsulations at the molecular level, such that they are “dissolved” into the water in smaller, more mobile units. Responding to the complexity of NAPL compound has resulted in SPTT mixtures that are selectively applicable to specific ranges of NAPL compounds (i.e., light-range gasoline, medium-range fuel-oil, heavy range bunker-C, MTBE, and chlorinated solvents). The SPTT molecules are environmentally safe and are highly biodegradable (97% in les than 27 days).

Underground (in-situ) contact between SPTT mixtures and NAPL contamination is accomplished through injection wells or injection galleries. The resulting SPTT-NAPL micelle-encapsulations liberate the NAPL from the soils and or free-phase, than once dissolved can be extracted from the soil and groundwater milieu via extraction wells for on-site treatment. Further, SPTT reduces the NAPL mass that would otherwise be released as vapor emissions. Case studies demonstrate that project goals are achieved at 95% of small to medium size sites in less than 18 months and often within 12 months. Hence, this recently patented technology (ca. 2001) is a proven method to expedite soil and groundwater remediation with significant project cost and time savings compared to many other alternatives available.

The ex-situ application method uses modified roll0off de-water units (25-35 cubic yards) for the soil treatment. The contaminated soil is loaded into the unit, and then submerged with SPTT laden water. The SPTT/Water phase is circulated through the soil bed resulting in rapid liberation of NAPL contamination form the solid (Soil) phase into the liquid (Water) phase in as little as 4 hours. Case studies have demonstrated this to be a portable, scalable, economic soil treatment alternative.

Thermal Desorption of Dioxin Contaminated Soil in Penny’s Bay, Hong Kong

Matthew Ming Ching Ko, Maunsell Environmental Management Consultants Ltd., Room 1213-1219, Grand Central Plaza, Tower 2, 138 Shatin Rural Committee Road,   Sha Tin, New Territories, Hong Kong, Tel: 2893 1551, Fax: 2891 0305, Email: matthew.ko@maunsell.com.hk

The Decommissioning of the former Cheoy Lee Shipyard at the Penny’s Bay will release land for the construction of infrastructure associated with the Hong Kong International Theme Park.  An extensive site investigation at the shipyard, which covered about 19 hectares, was carried out in 2001 to characterise the nature and extent of contamination.  The laboratory results revealed that parts of the shipyard site were contaminated.  The principal contaminants comprised Heavy Metals, Total Petroleum Hydrocarbons (TPH), Semi-volatile Organic Compounds (SVOCs) and Dioxins.  Dioxin-contaminated soil was found in a burn pit area, mainly confined to shallow ground, and extended over some 3 hectares.  The total quantity of contaminated soil was estimated to be about 100,000m³ in which about 30,000m³ of soil is contaminated with dioxins based on the pre-excavation site investigation.  A maximum concentration of 109 ppb Toxicity Equivalence (TEQ) dioxins and an average of about 9 ppb TEQ in the soil samples collected from burn pit were observed.  Based on the most stringent clean-up standard of 1 ppb dioxin TEQ, an environmentally acceptable and cost-effective strategy for decontamination of the dioxin-contaminated soil was developed.  The principal remediation techniques included off site treatment at To Kau Wan (TKW) using indirectly heated thermal desorption and the subsequent destruction of thermal desorption residue by incineration at the Chemical Waste Treatment Centre. Cement solidification of treated soil was then implemented to immobilise the heavy metals.  Excavation of the dioxin-contaminated soil and the transportation of the soil to TKW was completed in May 2003.  The thermal desorption plant commenced its operation in July 2003 and the work is anticipated to be complete in late 2004. This paper describes some of the technical details of the thermal desorption work.

Geotechnical Properties of Cement Stabilized Fly Ash-Bentonite Mixture as Liner Material

H Lakshmikantha, Assistant Environmental Officer, Karnataka State Pollution Control Board, KSPCB-GTZ, HAWA Project Office, 22^nd Floor, P U Building, M G Road, Bangalore-560 001, India, Email: lkdp2k@rediffmail.com
P V Sivapullaiah, Associate Professor, Department of Civil Engineering, Indian Institute of Science, Bangalore - 560 012, India, Fax: 91-80-360 0404, Email: siva@civil.iisc.ernet.in

Landfill liner acts as a barrier to minimize the migration of leachate. The use of waste material such as fly ash is being considered for liner construction. Most of fly ash are pozzolanic and hence may possess capacity to counter the effects of leachate. The un-burnt carbon present in fly ash helps to adsorb many ions present in the leachate. To further reduce the permeability and to improve the adsorption capacity, addition 20% by weight of bentonite is included. But the soil containing 20 % amount of bentonite will shrink and swell, also loose strength on wetting. The properties of fly ash containing bentonite could be altered by leachate.  Hence in this study it is proposed to enhance the suitability of fly ash amended with bentonite by stabilizing the mixture with 1% by weight of cement. Stabilized fly ash-bentonite possesses low shrinkage and hence does not crack. Compacted stabilized fly ash-bentonite mixture undergoes very little volume changes and it further reduces with curing. It has also been shown that stabilized mixture develops good strength. The permeability of fly ash, which is reduced after amending with bentonite is further, reduced after stabilization. Thus, pozzolanic fly ash with bentonite after stabilizing with cement could be a suitable liner material.

Monitoring Improvement in Water Quality Following Reclamation of Acidic Coal Refuse with Biosolids

Pauline V. Lindo, Ph.D., Lue Hing R&D Complex,             MetropolitanWater Reclamation District of Greater Chicago, 6001 W. Pershing Road, Cicero, IL  60804, Tel: 708-588-4109,    Fax: 708-780-6706, Email:  pauline.lindo@mwrd.org
Thomas C. Granato, Ph.D., Lue Hing R&D Complex, MetropolitanWater Reclamation District of Greater Chicago, 6001 W. Pershing Road, Cicero, IL  60804, Tel: 708-588-4063, Fax: 708- 780-6706, Email:  thomas.granato@mwrd.org
Richard. I. Pietz, Ph.D., Lue Hing R&D Complex, MetropolitanWater Reclamation District of Greater Chicago, 6001 W. Pershing Road, Cicero, IL  60804, Tel: 708-588-4116, Fax: 708-780-6706, Email: richard.pietz@mwrd.org
Carl Carlson, Jr., MS, R&D Laboratories, Fulton County, MetropolitanWater Reclamation District of Greater Chicago, 15779 E. County Highway 5, Cuba, IL  61427, Tel: 309-647-8200, Fax: 309-647-3566, Email:  carl.carlson@mwrd.org 

A long-term field study was initiated for the reclamation of an acid-generating coal refuse pile in St. David, Illinois, using ten combinations of six levels of biosolids (0-3,360 Mg ha^-1) with/without clay (10.2 cm) and agricultural lime (179 Mg ha^-1).  The treatments were applied to ten 0.405-ha plots, and five cover crops were planted, followed by mulching.  A lysimeter was placed in each plot to monitor water quality monthly over thirteen years, following treatment applications in 1987. Statistical analysis (SAS) of concentrations of twenty-one chemical parameters showed no significant differences (p³0.05) among the treatments in acidity, TSS, total P, Al, Cd, Cr, Cu, Fe, Mn, Pb, and Zn.  In comparison with the control, there was significant improvement (p£0.01) in pH, EC, alkalinity, Cl^-, SO₄^2-, TDS, Ni, and all others listed above.  Lysimeter samples from the two highest biosolids levels (2,800 and 3,360 Mg ha^-1) initially contained NH₄-N, NO₂-N, and NO₃-N at concentrations of 41.4-598, 0.051-1.88, and 474-525 mg L^-1, respectively, which decreased 90-99% by the year 2000.  Within two years of biosolids application, active acidity in samples decreased 100-fold (pH 3.4®5.3), while SO₄^2- decreased by a maximum of 96% (39,400®1,500 mg L^-1).  This resulted in decreased solubilities of most metals by 1993, and of Ni and Pb by 1997.  Acidity, TSS, TDS, EC, Cl^-, and SO₄^2- were greatly reduced and attained equilibrium five to six years after biosolids application.  Data clearly indicate that the biosolids were exceedingly beneficial in the reclamation of the acidic coal refuse site, resulting in marked improvement in water quality.

Composition, Peculiarities and Methods of Utilization of Oil Wastes

Z.A. Mansurov, Al-Farabi Kazakh National University, Al-Farabi Ave., 71, Almaty, 480078, Kazakhstan, Tel: (8-3272) 47-26-73, Fax: (8-3272) 47-26-09, Email mansurov@kazsu.kz
E.K. Ongarbayev, Al-Farabi Kazakh National University, Al-Farabi Ave., 71, Almaty, 480078, Kazakhstan, Tel: (8-3272) 41-57-78

Oil-and-gas productive industry occupies a leading place in the world economy. Every year the volume of produced and transported oil is increasing in the world. However, this productive industry is one of the largest pollutants of soils, water and air. In oil-producing regions great territories are polluted by spilled oil and oil slime as a result of various failures during the process of oil production and pipeline transportation. Transport losses of oil from oil-trunk pipelines are considerable.

The aim of the work is to determine composition and peculiarities of oil contaminated soils, oil slimes and lake oil from deposits of the Republic of Kazakhstan and on their basis develop methods of utilization.

Physicochemical characteristics of a number of oil wastes and their organic and mineral parts are determined in the work. The increased content of pitches and asphaltenes are typical for organic part of oil wastes that is the result of climatic factors effect on wastes in the process of long-term storage in open storehouse. Therefore, while the developing of rational variants of the processing of organic part of wastes its utilization for production of road-building materials is of a great interest.

Methods of bitumen obtaining from organic part of oil wastes and asphalt concrete mixture preparation by direct oxidation of oil wastes were proposed. Road and building bitumen were obtained by oxidation of organic part of oil wastes. Obtained asphalt concrete mixtures at the oxidation of oil wastes showed values of breaking point of compression 1.5-1.9 MPa and water saturation 0,2-0,3 vol. %. Methods of coke obtaining from organic part of oil wastes and claydite by utilization of oil wastes were proposed.

Modeling the Market for Long-Term Monitoring

Carlos Pachon, U.S. EPA Office of Superfund Remediation & Technology Innovation, USEPA Headquarters, Ariel Rios Building, 5102G, 1200 Pennsylvania Avenue, N. W. , Washington, DC 20460, Tel: 703-603-9904
Danielle Gratton, Tetra Tech EM Inc., Tel: 360-698-7257 
Sashi Vissa, Tetra Tech EM Inc., Tel: 703-390-0644
Peter Shields, Tetra Tech EM Inc., 1881 Campus Commons Drive, Suite 200, Reston, VA 20191, Tel: 703-390-0659

Based on the report “Treatment Technologies for Site Cleanup: Annual Status Report (11^th Edition)” (EPA-542-R-03-009), over 1,100 Superfund sites have remedies that may require long-term monitoring of groundwater to ensure their continued effectiveness.  These remedies include treatment remedies, such as pump and treat (P&T) of groundwater and permeable reactive barriers, containment remedies, such as capping and vertical engineered barriers, and other remedies, such as monitored natural attenuation and some institutional controls.  One of the most common of these remedies, P&T, is being used at 743 Superfund sites.  The investment needed for long-term monitoring at these sites will result in a continuing demand for services and technologies that provide better, faster, and cheaper environmental monitoring. Government officials need improved information about the future demand for monitoring services so that they can better prioritize support of technology research and development efforts.   Technology vendors, developers, and service providers are also able to identify business opportunities. This presentation provides the results from the first program-wide assessment of long-term monitoring needs at Superfund sites using P&T, including an analysis of the market for long-term monitoring equipment and services.  It presents estimates of current costs to the Superfund program for long-term monitoring of P&T systems.  It also presents estimated future expenses and trends over time based on anticipated long-term monitoring needs.  In addition, it provides the results of a sensitivity analyses of the effects of key variables, such as the introduction of emerging monitoring, sampling, and analytical methods, the use of geophysical and remote sensing technologies, the application of optimization lessons learned and rules of thumb, and changes in sampling and analytical costs.  The analysis is based on a cost model developed using standard engineering practice, published information from existing P&T projects, known estimates of long-term monitoring requirements, existing cost models, and EPA databases on P&T applications at Superfund Sites. Preliminary findings for this research are being presented at the Federal Remediation Technologies Roundtable conference on Accelerating Site Closeout, Improving Performance, and Reducing Cost Through Optimization (June 2004 in Dallas, TX).

Design/Build of an Emergency Multiphase Extraction System

Frank Ricciardi, P.E., Weston & Sampson Engineers, Inc. 5 Centennial Drive, Peabody, MA 01906, Tel: 978-532-1900, Fax: 978-977-0100, Email: ricciarf@wseinc.com  
Kelley Race, P.G., LSP, Weston & Sampson Engineers, Inc. 5 Centennial Drive, Peabody, MA 01906, Tel: 978-532-1900, Fax: 978-977-0100, Email: racek@wseinc.com
Ken Bisceglio, CHMM, Weston & Sampson Engineers, Inc. 5 Centennial Drive, Peabody, MA 01906, Tel: 978-532-1900, Fax: 978-977-0100, Email: bisceglik@wseinc.com

At a bus maintenance garage, routine tank tightness testing (TTT) for a 10,000-gallon diesel underground storage tank (UST) revealed a leak emanating from the conveyance piping between the UST and the diesel dispenser. Investigation activities implemented included gauging monitoring wells on the site, assessing nearby catch basins and manholes for the presence of light non-aqueous phase liquid (LNAPL), and utilizing direct-push drilling techniques to quickly install numerous small-diameter monitoring wells and soil gas monitoring points.  Gauging activities revealed a plume of LNAPL over 20,000 square feet covering a portion of the Site and extending in the downgradient direction beneath the adjacent street.

Timely remediation was required since LNAPL had migrated to within 50 feet of the nearby residential area and elevated concentrations of air-phase petroleum hydrocarbons were measured in soil gas. Numerous product recovery techniques were evaluated for implementation at the site including:

• Multiphase extraction utilizing drop tubes

• Multiphase extraction using a total fluids pump and applied vacuum

• Product recovery via pneumatic pumps

• Product recovery via electric product-only pumps

• Product recovery using passive canisters

The design of a product–only recovery system utilizing pneumatic pumps was implemented in the short term with the goal of upgrading the system in the future with groundwater extraction and enhanced product recovery via applied vacuum/soil vapor extraction. Project successes include elimination of potential vapor intrusion to indoor air, product recovery system design, upgrade to a multiphase extraction system, LNAPL recovery of over 3,000 gallons in less than one year and significant reduction in the size of the LNAPL plume.

Overcoming Site Challenges to Optimize an Inactive LNAPL Containment & Recovery System

Frank Ricciardi, P.E., Weston & Sampson Engineers, Inc. 5 Centennial Drive, Peabody, MA 01906, Tel: 978-532-1900, Fax: 978-977-0100, Email: ricciarf@wseinc.com 
Kelley Race, P.G., LSP, Weston & Sampson Engineers, Inc. 5 Centennial Drive, Peabody, MA 01906, Tel: 978-532-1900, Fax: 978-977-0100, Email: racek@wseinc.com
Ken Bisceglio, CHMM, Weston & Sampson Engineers, Inc. 5 Centennial Drive, Peabody, MA 01906, Tel: 978-532-1900, Fax: 978-977-0100, Email: bisceglik@wseinc.com

An existing LNAPL containment and recovery system located in southeastern Massachusetts was installed following an underground storage tank leak in the early 1990s. The ensuing leak produced an LNAPL plume over 20,000 square feet migrating downgradient underneath an active commuter train line into a wetland. As part of the emergency response actions, an impermeable barrier and recover trench were installed prior to the wetlands. Four product recovery sumps, two located in the recovery trench, two in the source area, and multiple observation wells were also installed at the site.  

Numerous logistical and site-related complications had to be overcome to optimize the LNAPL Recovery system that had been inactive for over two years. An active commuter rail line, which presented serious safety concerns, roughly bisected the LNAPL plume. The rail line also complicated the establishment of electrical service for any automated systems since power would need to cross the lines. Also, a high groundwater table and numerous issues relating to flooding/ponding water and breakout of free-phase petroleum product existed. The source area (former UST) is 15 feet above the train line and recovery trench, dropping quickly on a steep slope. Since the current property owner had little available capital, additional monetary resources were limited.

Optimization alternatives were evaluated that incorporated all these site-related and logistical issues to activate/replace the existing system and to increase LNAPL recovery rates. These alternatives included an evaluation of:  

• Solar and marine-battery operated LNAPL recovery systems
• Initiating groundwater depression 
• Placing sorbent booms in the area of petroleum breakout
• Installing additional product recovery skimmers
• LNAPL flushing technologies (i.e. steam, surfactants, and co-solvents) and
• Upgrade and repair of existing LNAPL recovery equipment

The evaluation was presented and the most cost-effective, logistical alterbative will be selected for implementation.

Useful Design and Cost-Estimation Tool for Air Handling Systems on Temporary Structures for MGP Sites

Anthony Mazzoni, TIGG Corporation, 800 Old Pond Road, Suite 706, Bridgeville, PA  15017, Tel: 412-257-9580, Fax: 412-257-8520, Email: amazzoni@tigg.com
John Sherbondy, TIGG Corporation, 800 Old Pond Road, Suite 706, Bridgeville, PA  15017, Tel: 412-257-9580, Fax: 412-257-8520, Email: jsherbondy@tigg.com  

The remediation of contaminated manufactured gas plant (MGP) sites can pose solid, liquid and air emission concerns.  Depending on technologies selected to remediate the site, one or all of the concerns could come into play.  Generally, the solids (soil) can be treated on-site, hauled off site for disposal and thermally treated, or treated in-situ. Rainwater or excavation water can be stored, treated on-site with known activated carbon technologies or hauled to a POTW for treatment.  Since MGP sites are generally located in urban settings, toxic air emissions and work-site odors are areas of particular awareness.

An effective solution for control of toxic emission and odor is to cover the site with a temporary structure during remediation activities.  These structures are used for covering the workspace and offer advantages such as all weather work, containment of dust and noise abatement.  However, a covered site poses additional issues such as release of toxic emissions during opening and closing doors and creating an environment that may require additional protective equipment for workers.  The most effective means of controlling toxics and odors is to create a negative pressure inside the structure and treat air prior to release through activated carbon. In addition, fresh air is required to enable working in Level C or D environment. 

This paper discusses all the engineering and economic issues that must be addressed before the air purification system can be properly designed.  Such things as required air changes, size of building, mode of operation and the need for prefiltration before the carbon adsorber must be discussed.

Also, presented is a technique to quickly and easily determine the cost of a system once the size of the structure and the required number of air changes is known.  This information may be used for the purposes of optimizing cost-effectiveness for the alternative design possibilities.

Optimization of a Pump and Treat System at the Massachusetts Military Reservation

Nigel Tindall, CH2M HILL, 318D East Inner Road, Otis ANG Base, MA 02542-5028, Tel:  508-968-4670 x 5620, Fax:  508-968-4916, Email: ntindall@ch2m.com
Rose H. Forbes, P.E., Air Force Center for Environmental Excellence, 322 East Inner Road , Otis ANG Base, MA 02542-5028, Tel:  508-968-4670 x 5613, Fax:  508-968-4476, Email:  rose.forbes@brooks.af.mil

In September 1997, a pump and treat system began operating to remediate the Fuel Spill-12 (FS-12) groundwater plume at the Massachusetts Military Reservation.  The contaminants of concern within the FS-12 plume are benzene and ethylene dibromide.  The FS-12 plume originated from a fuel pipeline leak in the early 1970s where approximately 70,000 gallons of both aviation gasoline and jet fuel were released to the subsurface.  The original design of the remedial system consisted of 25 extraction wells operating at a total design rate of 772 gallons per minute.  The extracted groundwater is piped to a treatment plant where contaminants are removed using granular activated carbon filtration.  Treated water is returned to the aquifer through 23 reinjection wells.  At the time of the FS-12 system start-up in 1997, the plume covered a linear distance of approximately 4,500 feet, the maximum width of the plume was approximately 2,300 feet, and the maximum thickness was approximately 100 feet.  Over the past several years, the FS-12 remedial system has been modified through a series of optimization steps to improve plume recovery, reduce cleanup time, and reduce costs. The optimization effort is an ongoing process of evaluation and adjustment of system operation and monitoring and will continue as the vertical and horizontal extent of the plume contracts.  Groundwater modeling has proved to be a powerful tool in the system optimization process.  The FS-12 groundwater model has been used to determine the best combination of pumping and reinjection rates to more efficiently remediate the plume as its geometry changes.  The specific objectives of the optimization are to provide better extraction system efficiency while maintaining hydraulic capture of the plume, lower total flow rates, focus extraction stresses on the most contaminated zones within the aquifer, and minimize the recirculation of treated water.

Evaluating Monitored Natural Attenuation as a Possible Remedial Technology on a Contaminated Site

Neshia Wright, Norman J. Arnold School of Public Health, University of South Carolina, 800 Sumter Street, Columbia SC 29208, Tel: 803-777-6410, Fax: 803-777-3391, Email: neshiamohammed@hotmail.com
Lee Newman, Norman J. Arnold School of Public Health, University of South Carolina, 800 Sumter Street, Columbia SC 29208, Tel: 803-777-4795, Fax: 803-777-3391, Email: Newman2@gwm.sc.edu, lnewman@sph.sc.edu
and Savannah River Ecology Laboratory, Aiken SC

Chlorinated hydrocarbons are a widespread class of contaminants found in soil and groundwater. Within this group, perchlorethylene (PCE) and trichloroethylene (TCE) are two of the most common contaminants detected in the environment. Monitored natural attenuation (MNA) is a remedial technology that has been acknowledged by the Environmental Protection Agency (EPA) as a possible cleanup action on Comprehensive Environmental Recovery Cleanup Liability Act (CERCLA), Resource Conservation and Recovery Act (RCRA), and Underground Storage Tanks (UST) sites contaminated with chlorinated hydrocarbons. In a study located on the Chemical, Metal and Pesticide (CMP)