DOE/EA-1356 Environmental Assessment Proposed Changes to the Sanitary Biosolids Land Application Program on the Oak Ridge Reservation Oak Ridge, Tennessee February 2003 U.S. Department of Energy Oak Ridge Operations ACRONYMS AND ABBREVIATIONS ac acres ALARA as low as reasonably achievable AMSA American Metropolitan Sewer Association CEQ Council on Environmental Quality CSF cancer slope factor DOE U.S. Department of Energy EA environmental assessment EFPC East Fork Poplar Creek EPA U.S. Environmental Protection Agency EPS Effluent Polishing System (West End Treatment Facility) FONSI Finding of No Significant Impact ggram ha hectares HEAST Health Effects Assessment Summary Tables HI hazard index HQ hazard quotient IDP Industrial Discharge Permit IRIS Integrated Risk Information System kg kilogram l liter LET linear energy transfer LOAEL Lowest Observed Adverse Effect Level mg milligram mrem/yr millirem per year MSL mean sea level NEPA National Environmental Policy Act NOAEL No Observed Adverse Effect Level NPDES National Pollutant Discharge Elimination System NRC Nuclear Regulatory Commission ORNL Oak Ridge National Laboratory ORR Oak Ridge Reservation i PCB polychlorinated biphenyl POTW Publicly Owned Treatment Works PPE Personnel Protective Equipment RCRA Resource Conservation and Recovery Act RESRAD Residual Radioactivity computer model RfC reference concentration RfD reference dose ROI Region of Influence SHPO State Historic Preservation Office TDEC Tennessee Department of Environment and Conservation TWRA Tennessee Wildlife Resources Agency USFWS U.S. Fish and Wildlife Service WETF West End Treatment Facility WSMS Westinghouse Safety Management Systems ii EXECUTIVE SUMMARY The U.S. Department of Energy (DOE) proposes to raise the biosolids land application radionuclide loading limits from the current, self-imposed 4 mrem/yr lifetime loading to the Tennessee Department of Environment and Conservation (TDEC)-approved level of 10 mrem/yr. The planning level increase is necessary for industrial development within the Oak Ridge community. In addition, DOE proposes to allow the discharge of treated wastewaters from the West End Treatment Facility (WETF) to the Y-12 Plant and City of Oak Ridge sanitary sewer systems, resulting in an operational cost savings of approximately $133,000 per year. The Oak Ridge Reservation (ORR) Biosolids Land Application Program has been in operation since 1983, utilizing 6 application sites on a total of 133 ha (329 acres) and has been awarded a number of awards from regulators for excellence in biosolids management, most recently in 1999 by EPA Region IV, the program's permitting authority. WETF is a process wastewater treatment facility located at the Y- 12 Plant that treats low levels of contaminated wastewater for discharge directly through a National Pollutant Discharge Elimination System (NPDES) permitted outfall to East Fork Poplar Creek (EFPC). Residual Radioactivity (RESRAD) modeling was performed for the proposed 10 mrem/yr planning level increase. Risk factors were calculated for each nuclide. All nuclides were within the acceptable EPA and DOE risk of 1 x 10-4 for a resident living on the land application site, drinking the water, etc. These calculated risks represent a "worst-case" scenario because the existing land application sites are physically isolated and access to the public is restricted during biosolids land application operations. To obtain a forecast of what the actual application soil radionuclide concentrations would be at the end of site life, a predictive model was prepared. The results demonstrated that 47.1% of the proposed 10 mrem/yr planning level would be achieved for the most heavily loaded site, the Rogers Site. This corresponds to an approximate 4.71 mrem/yr for the cumulative exposure received on-site by a resident. Human health risk assessments were also performed using actual radioactive loading levels and land application operational parameters to simulate what the true exposure scenarios to a worker or a transient would be. The risk factors (4 x 10-7 for a worker and 1 x 10-7 for a transient) were well below the acceptability value of 10-4 and the maximum calculated dose received would be 0.143 and 0.016 mrem/yr for a worker and transient, respectively, representing little to no measurable increases in dose or risk for the proposed planning level increase. vii The addition of the WETF effluents into the sewer system also produces a negligible impact on both the risk and dose factors on the ORR land application sites and City of Oak Ridge NPDES discharge point. A total of 7.56 kg of uranium from WETF operations would be land applied on an annual basis on land application sites. This amount correlates to a 0.04 g/kg increase in the total uranium levels for the city biosolids and 0.002 mg/kg or 0.7 pCi/g increase in application site soils over the life of the most heavily loaded application site. Consequently, this increase in total uranium only represents 0.0014% of the proposed 10 mrem/yr planning level, which is negligible. A human health risk assessment was also performed for the proposed WETF sanitary sewer discharge limits and was compared to actual discharge analytical data for the existing WETF NPDES Outfall. The assessment was extremely conservative assuming no removal of WETF contaminants at the city wastewater treatment plant and no dilution with EFPC. Even using this conservative scenario, the calculated risk (4.59 x 10-9) of discharging treated WETF effluents to the sanitary sewer system was well below the acceptable risk value of 10-4. Minimal impacts to biota, natural resources, and humans would be expected under the proposed action based on the evaluation of socioeconomic and environmental factors. Combined chemical and radiological impacts to human health would be minimal and within or below DOE and EPA target ranges, as previously discussed. Transportation risk would also be very low. The no action alternative would impact the City of Oak Ridge's ability to sustain future industrial growth due to the lack of radionuclide capacity within the sewer system. This could force the city to alter and even discontinue existing government and commercial radionuclide discharges to the sanitary sewer system, limit industrial growth to remaining radionuclide capacity or leave the existing ORR land application sites altogether in favor of free distribution of the biosolids material to the public. This could directly impact the city's acceptance of the ORNL biosolids and could result in the management of sanitary ORNL biosolids as low level radioactive waste because of the lack of other viable sanitary waste options for the material. This change would result in an operational cost increase of $67,000 per year for DOE Oak Ridge Operations. Future commercial and DOE sanitary wastewater projects could also be affected by the city's limited radionuclide capacity; however, direct socioeconomic impacts are impossible to forecast. The projected cost savings of $133,000 per year for WETF operations would also not be realized. viii GLOSSARY GLOSSARY Adsorption Adhesion of molecules of gas, liquid, or dissolved solids to a surface. Anaerobic A life or process that occurs in, or is not destroyed by, the absence of oxygen. Aeration A process that promotes biological degradation of organic water. The process may be passive (as when waste is exposed to air) or active (as when a mixing or bubbling device introduces the air). Agronomic Rate The annual application rate which is based upon the total amount of nitrogen needed to grow a specific type of vegetation. Biosolids Solid particles that are physically separated and treated during the sanitary wastewater treatment process Buffer zones An area designated to separate certain features, such as streams, lakes, or roads, from impacts from sludge application. The width of buffer zones for sludge application is determined by the Tennessee Department of Environment and Conservation. Class A Biosolids that do not possess pathogenic organisms and meet all designated EPA standards for free release without the use of a permit Class B Biosolids that possess a minimal level of pathogens that are destroyed within the first few hours after application. The land application of these materials require a permit and adherence to specific site restrictions via EPA. Demographics Statistics relating to the dynamic balance of a population, especially with regard to density, distribution, and capacity for expansion or decline. Desiccation Drying out; plants or insects or microorganisms may dry out to the extent that they die. x Heavy metals Metallic elements with high atomic weights, for example, mercury, chromium, cadmium, arsenic, and lead. They can damage living things at low concentrations and tend to accumulate in the food chain. Herbaceous Plants having little or no woody tissue and persisting usually for a single growing season. Hydrogeology The geology of groundwater, with particular emphasis on the chemistry and movement of water. Hydrology The science dealing with the properties, distribution, and circulation of water. Influent Water, wastewater, or other liquid flowing into a treatment plant. Inorganic chemicals Chemical substances of mineral origin, not of basically carbon structure. Natural areas Areas on the Oak Ridge Reservation that have been established to protect state or federally listed rare species and species under status review for federal listing that occur on the Oak Ridge Reservation. The Natural Areas consist of a core area (actual location of the plants) and a buffer area for habitat protection. Organic chemicals Substances containing mainly carbon, hydrogen, and oxygen. Pathogens Microorganisms that can cause disease in other organisms or in humans, animals, and plants. They may be bacteria, viruses, or parasites and are found in sewage. Potable water Water that is safe for drinking and cooking. POTW Publicly owned treatment works: a waste treatment works, usually owned by a unit of local government and designed to treat domestic wastewaters. xi Radionuclide Radioactive element, characterized according to its atomic mass and atomic number, that can be man-made or naturally occurring.