Aaron Redman, HydroQual, Inc., 4914 W. Genesee St, Camillus, NY 13031, Tel: 315-484-6220, Fax: 315-484-6221 
Joy McGrath, HydroQual, Inc., 1200 MacArthur Blvd, Mahwah, NJ 07430, Tel: 201-529-5151, Fax: 201-512-3825
Thomas Parkerton, ExxonMobil Biomedical Sciences Inc., 1545 Route 22 East, PO Box 971, Annandale, NJ 08801-0971, Tel: 908-730-1068, Fax: 908-730-1199
Dominic Di Toro, Department of Civil and Environmental Engineering, 356 DuPont Hall, University of Delaware, Newark, DE 19716, Tel: 302-831-4092, Fax: 302-831-3640

Soil predicted no effect concentrations (PNECs) for a series of equivalent carbon (EC) number total petroleum hydrocarbon (TPH) fractions or "hydrocarbon blocks" were calculated using representative structures from a database of physicochemical properties for nearly 1500 individual petroleum hydrocarbon structures.  Equivalent carbon numbers correspond to boiling point intervals referenced to n-alkanes of a given carbon number.   The blocks were categorized as aliphatic or aromatic and covered EC numbers of 6 to 20 for aliphatic hydrocarbons and 6 to 30 for aromatic hydrocarbons.  The individual hydrocarbon structures in the database were assigned to the selected hydrocarbon blocks by boiling point and general hydrocarbon class.  PNECs were calculated with a modified Target Lipid Model (TLM) combined with a statistical extrapolation (HC5) to calculate dissolved hydrocarbon concentrations in soil porewater that are protective of 95% of all species in the TLM database.  The TLM was modified to make use of estimated organism lipid membrane-water partition coefficients (log K_MW ) for very hydrophobic compounds (log K_OW  > 5.5) where there is an observed deviation from the normally log-linear relationship between membrane- and octanol-water partition coefficients for less hydrophobic compounds.  The soil PNECs were calculated from porewater PNECs by using Equilibrium Partitioning theory.  The PNECs calculated with this approach are compared to measured soil toxicity data for terrestrial plants, microbes and invertebrates.  This approach offers improvement for environmental site assessments by allowing the composition of TPH in contaminated soils to be taken into proper consideration.

Somerville Community Exposure to Contaminants from Wood Treatment Facility Emissions

Paul Rosenfeld, Ph.D, UCLA School of Public Health, 16-035 CHS, Box 951772, Los Angeles, CA 90095, Tel: 310-795-2335, Email: prosenfe@ucla.edu
Rob Hesse, R.G., R.E.A, Soil/ Water/ Air Protection Enterprise, 201 Wilshire Blvd, 2nd Floor, Santa Monica, CA 90401, Tel: 310-795-0592, Email: rhesse@swape.com
Amy Hensley, M.S., UCLA School of Public Health, 16-035 CHS, Box 951772, Los Angeles, CA, 90095, Tel: 310-622-3350, Email: arhensley@gmail.com
Andrew Scott, B.S., Soil/ Water/ Air Protection Enterprise, 201 Wilshire Blvd, 2nd Floor, Santa Monica, CA 90401, Tel: 559-260-2180, Email: Andrew@swape.com  
James Clark, Ph.D., Soil/ Water/ Air Protection Enterprise, 201 Wilshire Blvd, 2nd Floor, Santa Monica, CA 90401, Tel: 310-907-6165, Email: jclark@swape.com

A wood treatment facility in Somerville , Texas has been operating for approximately 100 years treating railroad ties and telephone poles.  During the wood treatment process, a significant amount of toxic creosote, pentachlorophenol and copper chromium arsenic (CCA) was used.  Much of the chemicals used during the wood treatment process were released into the atmosphere and deposited on the Somerville community.  To evaluate the historic exposure to the community, chemical analysis of attic dust was conducted.  Attic dust was analyzed for dioxin/furans (dioxin TEQs), polychlorinated biphenols (PCBs), polycyclic aromatic hydrocarbons (PAHs), copper, chromium, arsenic, and hexavalent chromium.  The results from the analysis show a dioxin total TEQ maximum, upper confidence limit (UCL), mean, and minimum of 1229, 1178, 189, and 11 ng/kg, respectively.  For benzo[a]pyrene TEQs, the maximum, UCL, mean, and minimum were 708, 658, 112, and 0.98 mg/kg, respectively.  For arsenic, the maximum, UCL, mean, and minimum were 51, 22, 8.9, and 2.8 mg/kg, respectively.  The chromium maximum, UCL, mean, and minimum were 145, 46, 31, and 8 mg/kg, respectively. The UCLs were calculated using ProUCL software.The results of this field investigation demonstrate that the community was exposed to elevated concentrations of contaminants from the wood treatment facility.

Risk Assessment of Sewage from Leaky Sewers in Urban Underground for Soil and Groundwater

Dr.-Ing. J. Hua, P. An, M. Paul, PD Dr. C. Gallert and Prof. Dr. J. Winter, University of Karlsruhe, Department of Biology for Engineers and Biotechnology of Wastewater treatment, Am Fasanengarten, D-76228 Karlsruhe, Germany, Tel: 0049-721-608-2297 or –2696. Email: Claudia.Gallert@iba.uka.de, Josef.Winter@iba.uka.de

Background: Many sewers are more than 50 years old and leaky, and often release more than 20 % of the total sewage into the underground. The raw sewage is trickling through the vadose zone and non-adsorbed/non-degraded residual compounds enter the groundwater. To assess the risc of groundwater contamination by sewage the German Research Foundation (Deutsche Forschungsgemeinschaft) funded laboratory, pilot and in-situ studies at the University of Karlsruhe.

Research tools: The fate of trickling sewage was investigated in water-saturated and nonsaturated, aerobic or anaerobic sand columns, in a 3x3x4 m “model soil compartment with a leaking sewer” at  the sewage tretatment plant in Karlsruhe and in-situ in a number of thrilled groundwater wells in the neighbourhood of leaking sewers.

Results of study: Long-term trickling of sewage through different sand columns and the model channel, as well as in-situ investigations of groundwater from urban underground revealed the following results:

1. Leaking rates in sandy soil vary with concentration and leaking time within a wide range. No permanent colmation was observed.
2. Most of the COD of sewage is degraded within the first 50 cm trickling stretch in sandy underground. Even after a trickling stretch of 2.5 m 8-10 % of the COD of raw sewage remain as non-biodegradable compounds, containing (new) humic acid-like and xenobiotic substances, as well as inorganic sewage compounds. 
3. In the center of an anaerobic sewage plume heavy metals are precipitated and immobilized under anaerobic conditions by sulfide steming from sulfate reduction. However, when trickling rates are decreasing and the plume gets aerobic, metal sulfides are reoxidized by aerobic conversion to sulfates and these are dislocated to deeper layers.
4. A biofilm and EPS is formed on the sand grains, leading to an increased moisture content and thus to a longer contact time of the sewage with microorganisms. This leads to a somewhat better removal of pollutants.
5. Although the sandy soil acts as a filter for microorganisms, more than 3000 bacteria/ml from the sewage reach the groundwater, containing many faecal microorganisms, such as enterococci and coliforms.
6. Boron can be used as an indicator of sewage pollution of groundwater.

Lab-scale and field studies revealednthe above results and indicated that  trickling sewage contaminates soil and groundwater considerably.  

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