Pharmaceuticals and Personal Care Products in Solids: Analysis and Field Results for Sediment, Soil, and Biosolid Samples
Edward T. Furlong, U.S. Geological Survey, Denver, CO

Detailed CVOC Source Area Investigation in the Context of a Fractured Bedrock Conceptual Site Model: A Case Study
James H. Vernon, ENSR International, Gilford, NH

Behavior of Alkyl Leads in Gasoline NAPL During Long Term Contact with Water

Gregory S. Douglas, NewFields Environmental Forensics Practice, 100 Ledgewood Place, Rockland, MA, 02370, Tel: 781-681-5040, Fax: 781-681-5048, Email: gdouglas@newfields.com
Steven D. Emsbo-Mattingly, NewFields Environmental Forensics Practice, 100 Ledgewood Place, Rockland, MA, 02370,Tel: 781-681-5040, Fax: 781-681-5048, Email: smattingly@newfields.com
Scott A. Stout, NewFields Environmental Forensics Practice, 100 Ledgewood Place, Rockland, MA, 02370, Tel: 781-681-5040, Fax: 781-681-5048, Email: sstout@newfields.com
Allen D. Uhler, NewFields Environmental Forensics Practice, 100 Ledgewood Place, Rockland, MA, 02370, Tel: 781-681-5040, Fax: 781-681-5048, Email: auhler@newfields.com
Kevin J. McCarthy, NewFields Environmental Forensics Practice, 100 Ledgewood Place, Rockland, MA, 02370, Tel: 781-681-5040, Fax: 781-681-5048, Email: kmccarthy@newfields.com

Tetraethyllead (TEL) has been added to gasoline as an antiknock agent since the 1920’s.  Its use in the United States peaked in the late 1960’s, was phased down in the late 1980s and banned as an automotive fuel additive in the mid 1990s.  The prohibition of lead alkyls in automotive gasoline has substantially reduced the human and ecological exposure to these toxic contaminants however health and safety concerns still persist today.  One potential source of these compounds still exists within the large volume of leaded gasoline non aqueous phase liquids (NAPL) underlying legacy releases at former leaded gasoline stations, bulk fuel storage facilities and pipelines.  Despite the potential problems associated with these contaminants, little is known regarding their ultimate fate in soils, and less is known about their environmental fate within the leaded gasoline NAPL present on the groundwater.  At issue in this study is the chemical fate of TEL and related organic lead compounds (tetramethyl lead (TML), methyltriethyl lead (MTEL), trimethylethyl lead (TMEL), and diethyldimethyl lead (DMDEL) in NAPL while in contact with water.  Laboratory studies designed to measure NAPL alkyl lead degradation on groundwater demonstrated that over a 20 month period greater than 90% of the TEL could be degraded by hydrolysis.  For gasoline containing reactive alkyl lead mixtures relative degradation rates are as follows: TEL > TML > MTEL) ≥ TMEL and DMDEL.  Field data from former gasoline station sites confirms the laboratory results and documents the composition and degradation of legacy gasoline releases.  These field data demonstrate that the hydrolysis of alkylated lead compounds is particularly significant in thin NAPL formations due to the high surface area to volume ratio at the ground water interface.  This work provides new information concerning the fate of alkyl lead compounds in NAPL samples and has significant implications regarding the use of alkyl lead concentrations in NAPL for age dating gasoline. 

Pharmaceuticals and Personal Care Products in Solids: Analysis and Field Results for Sediment, Soil, and Biosolid Samples

Edward T. Furlong, U.S. Geological Survey, PO Box 25046, MS 407, Building 95, Denver Federal Center, Denver, CO 80225, Tel: 303-236-3941, Fax: 303-236-3499, Email: efurlong@usgs.gov
Chad A. Kinney, Department of Chemistry/Biochemistry, Eastern Washington University, 226 Science Building, Cheney, WA 99004-2440, Tel: 509-359-7932, Email: ckinney@mail.ewu.edu
Imma Ferrer, Dpt. Hidrogeologia y Quimica Analitica, Universidad de Almeria, Carretera Sacramento s/n, 04120 La Cañada San Urbano, Almeria,  Espana, Tel: 34-666-23-6863, Email:iferrer@ual.es
Stephen L Werner, U.S. Geological Survey, PO Box 25046, MS 407, Building 95, Denver Federal Center, Denver, CO 80225, Tel: 303-236-3966, Fax: 303-236-3499; Email: slwerner@usgs.gov
Jeffery D. Cahill, U.S. Geological Survey, PO Box 25046, MS 407, Building 95, Denver Federal Center, Denver, CO 80225, Tel: 303-236-3256, Fax: 303-236-3499, Email:jdcahill@usgs.gov

Pharmaceuticals and personal-care products (PPCPs) have been described as ubiquitous complex mixtures present at trace concentrations in surface- and ground-water samples throughout the United States and Europe.  Sediment, soil, and biosolids have been much less studied, and might be important as sources of PPCPs to surface- and groundwater.  The means for mobilizing PPCPs from solids will vary, but a critical evaluation of PPCP compositions and concentrations in these solids and a comparison between solids is necessary to evaluate their importance in the transport and fate of PPCPs in the geosphere and hydrosphere.  In this study, a series of soil, sediment, and biosolid samples were extracted by accelerated solvent extraction and analyzed by high-performance liquid chromatography (HPLC) coupled with single or tandem mass spectrometry (MS or MS/MS) to identify and quantify PPCPs.  Method recovery studies using naturally occurring organic matter (NOM )-containing and NOM-free sediments suggest that the primary effect of NOM is to sequester PPCPs and shield them from extraction.  Staged amendment experiments indicate that the PPCP recoveries subsequent to extraction are not substantially diminished by the presence of NOM matrix components, suggesting incomplete extraction of PPCPs from NOM-containing soils, after equilibration for 24 hours and under extraction conditions previously determined to be optimal.  In these samples, overall PPCP concentrations generally are similar in soils and sediments, and substantially greater in biosolids.  The distributions of different PPCPs in all three matrix types were comparable.  The PPCPs determined in solid matrixes differ compositionally from those most commonly detected in water, although physical properties, such as predicted partitioning coefficients commonly used to estimate solid/water distributions, are inadequate predictors of whether a PPCP will preferentially reside on solids.  Mechanistic studies of PPCP partitioning and sorption behavior are necessary to understand the processes that bind PPCPs to solids.

Detailed CVOC Source Area Investigation in the Context of a Fractured Bedrock Conceptual Site Model:  A Case Study

James H. Vernon, Ph.D., ENSR International, 401 Gilford Avenue, Suite 220, Gilford, NH, 03249, Tel:  603-524-8866, Fax:  603-524-9777, Email: jvernon@ensr.com
Patricia Shattuck, ENSR International, 401 Gilford Avenue, Suite 220, Gilford, NH, 03249, Tel:  603-524-8866, Fax:  603-524-9777, Email:  pshattuck@ensr.com
Mark D. Kauffman, P.E., ENSR International, 2 Technology Park Drive, Westford, MA, 01886, Tel: 978-589-3119, Fax: 978-589-3229, Email: mkauffman@ensr.com
Drew M. Clemens, P. G., US Army Corps of Engineers, New England District, 696 Virginia Road, Concord, MA, 01742-2751, Tel:  978-318-8861, Fax:  978-318-8614, Email: Drew.M.Clemens@nae02.usace.army.mil
Robert A. Leitch, P.E., US Army Corps of Engineers, New England District, 696 Virginia Road, Concord, MA, 01742-2751, Tel:  978-318-8033, Fax:  978-318-8663, Email: Robert.a.Leitch@usace.army.mil
Donald M. Maynard, P.G., The Johnson Company, 100 State Street, Suite 600, Montpelier, VT, 05602, Tel:  802-229-4600, Fax:  802-229-5876, Email:  dmm@jcomail.com

Dissolved-phase transport of groundwater contaminants through crystalline bedrock fractures is often highly heterogeneous and challenging to conceptualize.  Groundwater flow can be restricted to a discrete subset of connected bedrock fractures, while contaminant transport may not be well correlated with the degree of fracture-zone hydraulic activity.  While characterizing hydraulic interconnectivity between source areas and receptors and between individual wells is a desired component of a conceptual site model (CSM), scale issues may prevent the identification of specific contaminant pathways or the prediction of contaminant concentrations throughout a site. Detailed characterization in known or suspected contamination source areas, in the context of an existing CSM, not only guides remediation and monitoring strategies, but also enhances understanding of contaminant transport to potential off-site receptors.

The case study area in coastal Maine is underlain by fractured metavolcanic and intrusive bedrock, present at or near the ground surface.  Water levels are as deep as 120 feet in some wells.  Groundwater flow is restricted to fractures, lithologic contacts, or faults within the bedrock.  Chlorinated volatile organic compounds (CVOCs) discharged on site from past operations have been detected in wells at concentrations varying from more than 3,000 micrograms per liter to below detection limits, with a heterogeneous spatial distribution.  A variety of investigations has led to the development of a CSM for the site.  Information obtained from detailed source area investigations may allow identification of specific contaminant pathways within the source area, but not at the greater distances that are present between the source area and some receptors.   

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