United States Environmental Protection Agency Water Office of vVatar Regulations and Standards Washington, DC 20460 June, 1935 ices ------- PREFACE This document is one of a series of preliminary assessments dealing with chemicals of potential concern in municipal sewage sludge. The purpose of these documents is to; (a) summarize the available data for the constituents of potential concern, (b) identify the key 'environ- mental pathways for each constituent related to a reuse and disposal option (based on hazard indices), and (c) evaluate the conditions under which such a pollutant may pose a hazard. Each document provides a sci- entific basis for making an initial determination of whether a pollu- tant, at levels currently observed in sludges, poses a likely hazard to human health or the environment when sludge is disposed of by any of several methods. These methods include landspreading on food chain or nonfood chain crops, distribution and marketing programs, landfilling, incineration and ocean disposal. These documents are intended to serve as a rapid screening tool to narrow an initial list of pollutants to those of concern. If a signifi- cant hazard is indicated by' this preliminary analysis, a more detailed assessment will be undertaken to better quantify the risk from this chemical and "to derive criteria if warranted. If a hazard is shown to be unlikely, no further assessment will be conducted at this time; how- ever, a reassessment will be conducted after initial regulations are finalized. In no case, however, will criteria be derived solely on the basis of information presented in this document. ------- TABLE OF CONTENTS Page PREFACE i 1. INTRODUCTION .- 1-1 2. PRELIMINARY CONCLUSIONS FOR CHLOROFORM IN MUNICIPAL SEWAGE SLUDGE 2-1 Landspreading and Distribution-and-Mar.keting 2-1 Landfilling 2-1 Incineration 2-1 Ocean Disposal 2-1 3. PRELIMINARY HAZARD INDICES FOR CHLOROFORM IN MUNICIPAL SEWAGE SLUDGE 3-1 Landspreading and Distribution-and-Marketing 3-1 Landf illing '....: 3-1 Incineration 3-1 Index of groundwater concentration resulting from landfilled sludge (Index 1) 3-1 Index of cancer risk resulting from groundwater contamination (Index 2) 3-3 Ocean Disposal 3-5 4. PRELIMINARY DATA PROFILE FOR CHLOROFORM IN MUNICIPAL SEWAGE SLUDGE 4-1 Occurrence 4-1 Sludge 4-1 Soil - Unpolluted 4-1 Water - Unpolluted 4-1 Air 4-1 Food 4-1 Human Effects , 4-2 Ingestion • 4-2 Inhalation 4-3 Plant Effects 4-4 11 ------- TABLE OP CONTENTS (Continued) Page Domestic Animal and Wildlife Effects 4-5 Toxicity 4-5 Uptake 4-5 Aquatic Life Effects 4-6 Toxicity 4-6 Uptake 4-6 Soil Biota Effects 4-6 Physicochemical Data for Estimating Fate and Transport 4-6 5. REFERENCES 5-1 APPENDIX. PRELIMINARY HAZARD INDEX CALCULATIONS FOR CHLOROFORM IN MUNICIPAL SEWAGE SLUDGE A-l 111 ------- SECTION 1 INTRODUCTION This preliminary data profile is one of a series of profiles dealing with chemical pollutants potentially of concern in municipal sewage sludges. Chloroform (CHC^) was initially identified as being of potential concern when sludge is incinerated.* This profile is a compilation of information that may be useful in determining whether CHC13 poses an actual hazard to human health or the environment when sludge is disposed of by this method. The focus of this document is the calculation of "preliminary hazard indices" for selected potential exposure pathways, as shown in Section 3. Each index illustrates the hazard that could result from movement of a pollutant by a given pathway to cause a given effect (e.g., sludge •* air •*• human toxicity). The values and assumptions employed in these calculations tend to represent a reasonable "worst case"; analysis of error or uncertainty has been conducted to a limited degree. The resulting value in most cases is indexed to unity; i.e., values >1 may indicate a potential hazard, depending upon the assumptions of the calculation. The data used for index calculation have been selected or estimated based on information presented in the "preliminary data profile", Section 4. Information in the profile is based on a compilation of the recent literature. An attempt has been made to fill out the profile outline to the greatest extent possible. However, since this is a pre- liminary analysis, the literature has not been exhaustively perused. The "preliminary conclusions" drawn from each index in Section 3 are Summarized in Section 2. The preliminary hazard indices will be used as a screening tool to determine which pollutants and pathways may pose a hazard. Where a potential.hazard is indicated by interpretation of these indices, further analysis will include a more detailed exami- nation of potential risks as well as an examination of site-specific factors. These more rigorous evaluations may change the preliminary conclusions presented in Section 2, which are based on a reasonable "worst case" analysis. The preliminary hazard indices for selected exposure routes pertinent to incineration practices are included in this profile. The calculation formulae for these indices are shown in the Appendix. The indices are rounded to two significant figures. * Listings were determined by a series of expert workshops convened during March-May, 1984 by the Office of Water Regulations and Standards (OWRS) to discuss landspreading, landfilling, incineration, and ocean disposal, respectively, of municipal sewage sludge. 1-1 ------- SECTION 2 PRELIMINARY CONCLUSIONS FOR CHLOROFORM IN MUNICIPAL SEWAGE SLUDGE The following preliminary conclusions have been derived from the calculation of "preliminary hazard indices", which represent conserva- tive or "worst case" analyses of hazard. The indices and their basis and interpretation are explained in Section 3. Their calculation formulae are shown in the Appendix. I. LANDSPREADING AND DISTRIBUTION-AND-MARKETING Based on the recommendations of the experts at the OWRS meetings (April-May, 1984), an assessment of this reuse/disposal option is not being conducted at this time. The U.S. EPA reserves the right to conduct such an assessment for this option in Che future. II. LANDFILLING Based on the recommendations of the experts at the OWRS meetings (April-May, 1984), an assessment of this reuse/disposal option is not being conducted at this time. The U.S. EPA reserves the right to conduct such an assessment for this option in the future. III. INCINERATION The incineration of sludge is not expected to increase the concentration of CHC13 above background urban air concentration (see Index 1). Incineration of sludge is not expected to increase cancer risks to humans over the risk posed by background urban air concentrations of CHC13. IV. OCEAN DISPOSAL Based on the recommendations of the experts at the OWRS meetings (April-May, 1984), an assessment of this reuse/disposal option is not being conducted at this time. The U.S. EPA reserves the right to conduct such an assessment for this option in the future. 2-1 ------- SECTION 3 PRELIMINARY HAZARD INDICES FOR CHLOROFORM IN MUNICIPAL SEWAGE SLUDGE I. LANDSPREADING AND DISTRIBUTTON-AND-MARKETING Based on the recommendations of the experts at the OWRS meetings (April-May, 1984), an assessment of this reuse/disposal option is not being conducted at this time. The U.S. EPA reserves the right to conduct such an assessment for this option in the future. II. LANDPILLING Based on the recommendations of the experts at the ' OWRS meetings (April-May, 1984), an assessment of this reuse/disposal option is not being conducted at this time. The U.S. EPA reserves the right to conduct such an assessment for this option in the future. III. INCINERATION A. Index of Air Concentration Increment Resulting from Incinerator Emissions (Index 1) 1. Explanation - Shows the degree of elevation of the pollutant concentration in the air due to the incinera- tion of sludge. An input sludge with thermal properties defined by the energy parameter.(EP) was analyzed using the BURN model (Camp Dresser and McKee, Inc. (COM), 1984). This model uses the thermodynamic and mass balance relationships appropriate for multiple hearth incinerators to relate the input sludge characteristics to the stack gas parameters. Dilution and dispersion of these stack gas releases were described by the U.S. EPA's Industrial Source Complex Long-Term (ISCLT) dispersion model from which normalized annual - ground level concentrations were predicted (U.S. EPA, 1979). The predicted pollutant concentration can then be compared to a ground level concentration used to assess risk. 2. Assumptions/Limitations - The fluidized bed incinerator was not chosen due to a paucity of available data. Gradual plume rise, stack tip downwash, and building wake effects are appropriate for describing plume behavior. Maximum hourly impact values can be translated into annual average values. 3. Data Used and Rationale a. Coefficient to correct for mass and time units (C) = 2.78 x 10~7 hr/sec x g/mg • b. Sludge feed rate (DS) 3-1 ------- i. Typical = 2660 kg/hr (dry solids input) A feed rate of 2660 kg/hr DW represents an average dewatered sludge feed rate into the furnace. This feed rate would serve a commun- ity of approximately 400,000 people. This rate was incorporated into the U.S. EPA-ISCLT model based on the following input data: EP = 360 Ib H20/mm BTU Combustion zone temperature - 1400°F Solids content - 28% Stack height - 20 m Exit gas velocity - 20 m/s Exit gas temperature - 356.9°K (183°F) Stack diameter - 0.60 m ii. Worst = 10,000 kg/hr (dry solids input) A feed rate of 10,000 kg/hr DW represents a higher feed rate and would serve a major U.S. city. This rate was incorporated into the U.S. EPA-ISCLT model based on the following input data: EP = 392 Ib H20/mm BTU Combustion zone temperature - 1400°F Solids content - 26.6% Stack height - 10 m Exit gas velocity - 10 m/s Exit gas temperature - 313.8°K (105°F) Stack diameter - 0.80 m c. Sludge concentration of pollutant (SC) Typical • 0.049 mg/kg DW Worst 1.177 mg/kg DW The typical and worst sludge concentrations are the geometric mean and 95th percentile values from sludge concentration data from a survey of 40 publicly-owned treatment works (POTWs) (U.S. EPA, 1982). (See Section 4, p. 4-1.) d. Fraction of pollutant emitted through stack (PM) Typical 0.05 (unitless) Worst 0.20 (unitless) These values were chosen as best approximations of the fraction of pollutant emitted through stacks (Farrell, 1.984). No data was available to validate these values; however, U.S. EPA is currently testing incinerators for organic emissions. 3-2 ------- e. Dispersion parameter for estimating maximum annual ground level concentration (DP) Typical 3.4 Mg/m3 Worst 16.0 Ug/m3 The dispersion parameter is derived from the U.S. EPA-ISCLT short-stack model. f. Background concentration of pollutant in urban air (BA) = 7.48 Ug/m3 An average value (1530 ppt, v/v) was derived by the U.S. EPA (1984b) from urban air values calculated as ppt (parts per trillion) volume/volume. This value was converted from volume per unit volume to Ug/m3 (weight per unit volume). (See Section 4, p. 4-2.) Index 1 Values • Sludge Feed Fraction of Rate (kg/hr DW)a Pollutant Emitted Sludge Through Stack Concentration 0 2660 10,000 Typical Typical Worst 1.0 1.0 1.0 1.0 1.0 1.0 Worst Typical 1.0 1.0 1.0 Worst 1.0 1.0 1.0 a The typical (3.4 Ug/m3) and worst (16.0 yg/m3) disper- sion parameters will always correspond, respectively, to the typical (2660 kg/hr DW) and worst (10,000 kg/hr DW) sludge feed rates. 5. Value Interpretation - Value equals factor by which expected air concentration exceeds background levels due to incinerator emissions. 6. Preliminary Conclusion - The incineration of sludge is not expected to increase the concentration of CHC13 above background urban air concentration. B. Index of Cancer Risk Resulting from Inhalation of Incinerator Emissions (Index 2) 1. Explanation - Shows the increase in human intake expected to result from the incineration of sludge. Ground level concentrations for carcinogens typically were developed based upon assessments published by the U.S. EPA Carcino- 3-3 ------- gen Assessment Group (CAG). These ambient concentrations reflect a dose Level which, for a lifetime exposure, increases the risk of cancer by 10~°. For non- carcinogens, levels typically were derived from the Amer- ican Conference of Government Industrial Hygienists (ACGIH) threshold limit values (TLVs) for the workplace. 2. Assumptions/Limitations - The exposed population is assumed to reside within the impacted area for 24 hours/day. A respiratory volume of 20 m3/day is assumed over a 70-year lifetime. 3. Data Used and Rationale a. Index of air concentration increment resulting from incinerator emissions (Index 1) See Section 3, pp'. 3-1 to 3-3. b. Background concentration of pollutant in urban air (BA) = 7.48 Ug/m3 See Section 3, p. 3-3. c. Cancer potency = 4.6 x 10~^ (mg/kg/day)~^ A cancer potency for ingestion of 7.0 x 10~^ (mg/kg/day)"1 was derived by the U.S. EPA (1984a) based on studies of mice that developed liver tumors after being fed a CHCl3-contaminated diet. The cancer potency for inhalation was calculated by assuming a respective absorption for inhalation of 65%. (See Section 4, p. 4-2.) d. Exposure criterion (EC) = 7.6 x 10"^ Ug/m3 A lifetime exposure level which would result in a 10~6 cancer risk was selected as ground level concentration against which incinerator emissions are compared. The risk estimates developed by CAG are defined as the lifetime incremental cancer risk in a hypothetical population exposed continuously throughout their lifetime to the stated concentration of the carcinogenic agent. The exposure criterion is calculated using the following formula: EC _ 10~6 x 103 Ug/mg x 70 kg Cancer potency x 20 m3/day 3-4 ------- 4. Index 2 Values Sludge Feed Fraction of Rate (kg/hr DW)a Pollutant Emitted Sludge Through Stack Concentration 0 2660 10,000 Typical Typical Worst 98 98 98 98 98 98 Worst . Typical 98 98 98 Worst 98 98 99 a The typical (3.4 Ug/m3) and worst (16.0 Ug/m3) disper- sion parameters will always correspond, respectively, to the typical (2660 kg/hr DW) and worst (10,000 kg/hr DW) sludge feed rates. 5. Value Interpretation - Value > 1 indicates a potential increase in cancer risk of > 10~^ (1 per 1,000,000). Comparison with the null index value at 0 kg/hr DW indicates the degree to which any hazard is due to sludge incineration, as opposed to background urban air concentration. 6. Preliminary Conclusion - The potential for cancer risk for the null value, 0 kg/hr sludge feed rate, may be high due to the background urban air concentration chosen. The background Urban air value may reflect concentrations near pollution sources. Incineration of sludge is not expected to increase cancer risks to humans over the risk posed by background urban air concentrations of CHC13. IV. OCEAN DISPOSAL Based on the recommendations of the experts at the OWRS meetings (April-May, 1984), an assessment of this reuse/disposal option is not being conducted at this time. The U.S. EPA reserves the right to conduct such an assessment for this option in the future. 3-5 ------- SECTION 4 PRELIMINARY DATA PROFILE FOR CHLOROFORM IN MUNICIPAL SEWAGE SLUDGE I. OCCURRENCE A. Sludge 1. Frequency of Detection Data not immediately available. 2. Concentration Typical = 0.049 mg/kg DW (geometric mean Worst = 1.177 mg/kg DW (95th percentile) B. Soil - Unpolluted Data not immediately available. C. Water - Unpolluted 1. Frequency of Detection Data not immediately available. 2. Concentration a. Fresh water Data not immediately available. b. Seawater Data not immediately available. c. Drinking water Concentration mean = 0.083 mg/L max. = 0.47 mg/L Statistically derived from a survey of 40 POTWs pre- sented in.U.S. EPA, 1982. U.S. EPA, 1984b (p. 3-6) Human intake (assuming consumption of 2L/day) mean = 61 mg/year U.S. EPA, 1980a max. =,343 mg/year (p. C-2) 4-1 ------- U.S. EPA, 1984b (p. 1-D U.S. EPA, 1980a (p. C-5) U.S. EPA, 1984b U.S. EPA, 1980a (p. C-5) U.S. EPA, 1984b (p. 1-1) D. Air 1. Frequency of detection Ubiquitous in the environment 2. Concentration Bayonne, NJ 0.073 mg/m3 highest measured ambient air concentration Urban air 1530 ppt average derived from Table 3-9 (p. 3-31) 9.8 x 10~5 to 19.6 x 10~5 mg/m3 <10 ppt for rural or remote E. Food 1. Total average intake Data not immediately available. 2. Concentration Typical range 1 to 30 Ug/kg II. HUMAN EFFECTS A. Ingestion 1. Carcinogenicity a. Qualitative Assessment Has induced cancer by the oral route in at least two animal species at high and intermediate dose levels b. Potency .Cancer potency of 7.0 x 10~2 (mg/kg/day)~l was derived from studies of mice that developed liver tumors after fed a diet containing 238 to 477 mg/kg/day. c. Effects Tumors: liver, bladder, colon, and rectal cancer. 4-2 U.S. EPA, 1980a (p. C-4) U.S. EPA, 1984b (p. 13) U.S. EPA, 1984a (p. 8-78) ------- 2. Chronic Toxicity a. ADI Mean lethal dose »/*44g b. Effects Data not presented because cancer potency will be used to assess hazard. 3. Absorption Factor 100% absorption from gastrointestinal tract 4. Existing Regulations NIOSH time-weighted average exposure 2 ppm. FDA prohibits use in drugs, cosmetics, or food contact materials CAG 7 x 10~2 (mg/kg/day)"1 unit carcinogenic risk, which corresponds to a lifetime increase in cancer risk of 1 person in 100,000, equivalent to an intake of 0.01 mg/day B. Inhalation 1. Carcinogenicity a. Qualitative Assessment There is no-carcinogen data avail- able for animals due to inhalation. b. Potency The cancer potency for inhalation of 4.6 x 10~2 (mg/kg/day)"1 was derived from oral data from values presented in U.S. EPA, 1984a. The inhalation slope was estimated from the ingestion cancer potency of 7.0 x 10~2 (mg/kg/day)"1, assuming an absorption for ingestion and inhalation are 100% and 65% respectively. U.S. EPA, 1980a (p. C-10) U.S. EPA, 1980a (p. C-5) U.S. EPA, (p. 9) 1980b U.S. EPA, 1984c (p. 15) U.S. EPA, 1984a (p. 8-78) U.S. EPA, 1984a (p. 8-78) 4-3 ------- c. Effects Hepatocellular carcinoma in mice Renal epithelial tumors in rats Kidney tumors in mice Hepatomas in mice 2. Chronic Toxicity a.. Inhalation Threshold or MPIH 4300 ppm (20 minutes) threshold for "light intoxication". Long term exposure to 20-71 ppm (98- 346 mg/m3) for a 4-8 hour work day with occasional brief excur- sions to £ 1163 ppm may represent a LOAEL for symptoms of CNS (central nervous system) toxicity for humans. b. Effects Continued exposure to 20,000 ppm could result in respiratory fail- ure, direct depression of the myocardium, and death. 1500 to 15,000 ppm have caused cardiac arrythmias and extra systoles and hepatic necrosis and fatty degeneration. 3. Absorption Factor 49 to 77 percent via respiratory system 4. Existing Regulations OSHA 50 ppm or 244 mg/m3 10 minute exposure time NIOSH 2 ppm or 9.8 mg/m3 10 hour day and 40 hour week ACGIH recommends a time-weighted average of 10 ppm (50 mg/m3) and a short term exposure limit of 50 ppm (225 mg/m3) (15 minute). III. PLANT EFFECTS Data not immediately available. U.S. EPA, 1984c U.S. EPA, 1984b (p. 5-46) U.S. EPA, 1984b (p. 5-46) U.S. EPA, 1980a (p. C-5) U.S. EPA, 1980a (p. C-Z9) U.S. EPA, 1984c (p. 13) 4-4 ------- IV. DOMESTIC ANIMAL AND WILDLIFE EFFECTS A. Toxicity 150 and 410 mg/kg/day for rats produced severe toxic effects (oral) 25 ppm produced effects in liver and kidneys of male rats (inhalation) (122 mg/m^) 7 hrs/day exposure 24 ppm produced effects in livers and kidneys of guinea pigs but not at 50 ppm ^60 mg/kg/day (oral) produced depression of body weight of rats and mice 4-hour exposure (inhalation) at 100 ppm produced mild hepatic effect (increased incidence of moderate fatty infiltration for female mice at 200, 400 and 800 ppm. In addition, fatty infiltration, hepatic necrosis and increased serum enzyme activity were observed. Exposure of male mice to 5 mg/L (1.025 ppm) for 1 hour resulted in damage to kidneys (inhalation) 89 to 149 mg/kg (oral) for male mice resulted in kidney disfunction Mice (male) experienced renal necrosis after 20 mg/kg (oral) 30 mg/kg was the lowest observed adverse effect level (LOAEL) for hepatic effects on mice 15 mg/kg/day (6 day week) represents LOAEL for dogs for effects on the * liver B. Uptake Data not immediately available. U.S. EPA, 1984c (p. 3) U.S. EPA, 1984c (p. 5) U.S. EPA, 1984b (p. 5-47) U.S. EPA, 1984b (p. 5-48) U.S. EPA, 1984b (p. 5-50) 4-5 ------- V. AQUATIC LIFE EFFECTS A. Toxicity 1 . Freshwater a. Acute 28,900 Ug/L 48 hour Daphnia magna b. Chronic 1,240 ug/L 2. Saltwater a. Acute 96 hour LC5Q value of 81,500 pink shrimp b. Chronic Data noc immediately available. B. Uptake 14 day exposure: BCF = 6. Tissue half- life was less than 1 day. The suggests that residues would not be a hazard to consumers of aquatic life. Weighted average BCF of all freshwater and estuarine aquatic organisms = 3.75 C. Existing Regulations For freshwater - 500 Ug/L 24 hour average; should not exceed 1200 Ug/L at any time For saltwater - should not exceed 620 Ug/L 24 hour average and 1400 Ug/L at any time VI. SOIL BIOTA EFFECTS Data not immediately available. U.S. EPA, 1980a (p. 6) U.S. EPA, 1980a (p. B-l) U.S. EPA, 1980a (p. B-2) U.S. EPA, 1980a (p. C-4) U.S. EPA, 1980b (p. 9) 4-6 ------- VII. PHYSICOCHEMICAL DATA FOR ESTIMATING PATE AND TRANSPORT Vapor pressure: Solubility in water: Octanol/water parti- tion coefficient: Half-life in air: Half-life in water: Soil mobility: Bioconcentration factor: Boiling point: Melting point: Molecular weight: 150.5 mm Hg at 20°C 8200 mg/L at 20°C 93 80 days 0.3 to 3 days in rivers, 3 to 30 days in lakes (predicted as retardation factor for a soil depth of 140 m and organic carbon content of 0.0877.) 1.2 6 (in bluegill, Lepomis machrochirus) 61 to 62°C -63.5°C 119.39 U.S. EPA, 1984c (p. 1) U.S. EPA, 1980b U.S. EPA, 1980a 4-7 ------- SECTION 5 REFERENCES Camp Dresser and McKee, Inc. 1984. Development of Methodologies for Evaluating Permissible Contaminant Levels in Municipal Wastewater Sludges. Draft. Office of Water Regulations and Standards, U.S. Environmental Protection Agency, Washington, D.C. Farrell, J. B. 1984. Personal Communication. Water Engineering Research Laboratory, U.S. Environmental Protection Agency, Cincinnati, OH. December. U.S. Environmental Protection Agency. 1979. Industrial Source Complex (ISC) Dispersion Model User Guide. EPA 450/4-79-30. Vol. 1. Office of Air Quality Planning and Standards, Research Triangle Park, NC. December. U.S. Environmental Protection Agency. 1980a. Ambient Water Quality Criteria for Chloroform. EPA 440/5-80-033. Office of Water Regulations and Standards Criteria and Standards Division, Washington, D.C. U.S. Environmental Protection Agency. 1980b. Trichloromethane (Chloroform): Hazard Profile. Environmental Criteria and Assessment Office, Cincinnati, OH. 14 pp. U.S. Environmental Protection Agency. 1982. Fate of Priority Pollutants in Publicly-Owned Treatment Works. Final Report. Volume I. EPA 440/1-82-303. Effluent Guidelines Division, Washington, D.C. September. U.S. Environmental Protection Agency. 1984a. Health Assessment Document for Chloroform. External Review Draft. EPA 600/8-84- 004A. Office of Health and Environmental Assessment, Washington, D.C. U.S. Environmental Protection Agency. 1984b. Health Assessment Document for Chloroform, Part 1 and 2. EPA 600/8-840-004A. Office of Health and Environmental Assessment, Washington, D.C. 378 pp. U.S. Environmental Protection Agency. 1984c. Health Effects Assessment Document for Chloroform. ECAO-CIN-H010. Environmental Criteria and Assessment Office, Cincinnati, OH. 26 pp. 5-1 ------- APPENDIX PRELIMINARY HAZARD INDEX CALCULATIONS FOR CHLOROFORM IN MUNICIPAL SEWAGE SLUDGE I. LANDSPREADING AND DISTRIBUTION-AND-MARKETING Based .on the recommendations of the experts at the OWRS meetings (April-May, 1984), an assessment of this reuse/disposal option is not being conducted at this time. The U.S. EPA reserves the right to conduct such an assessment for this option in the future. II. LANDPILLING Based on the recommendations of the experts at the OWRS meetings (April-May, 1984), an assessment of this reuse/disposal option is not being conducted at this time. The U.S. EPA reserves the right to conduct such an assessment for this option in the future. III. INCINERATION A. Index of Air Concentration Increment Resulting from Incinerator Emissions (Index 1) 1. Formula _ , . (C x PS x SC x FM x DP) + BA Index 1 = — where: C = Coefficient to correct for mass and time units (hr/sec x g/mg) DS = Sludge feed rate (kg/hr DW) SC = Sludge concentration of pollutant (mg/kg DW) FM = Fraction of pollutant emitted through stack (unitless) DP = Dispersion parameter for estimating maximum annual ground level concentration (wg/m3) BA = Background concentration of pollutant in urban air (ug/m3) 2. Sample Calculation 1.0 = [(2.78 x 10~7 hr/sec x g/mg x 2660 kg/hr DW x 0.049 mg/kg DW x 0.05 x 3.4 ng/m3) + 7.48 yg/m3] t 7.48 yg/m3 A-l ------- B. Index of Cancer Risk Resulting from Inhalation of Incinerator Emissions (Index 2) 1. Formula '[(II - 1) x BA] 1- BA Index 2 = EC where: II = Index 1 = Index of air concentration increment resulting from incinerator emissions (unitLess) . BA = Background concentration of pollutant in urban air (yg/m3) EC = Exposure criterion (ug/m3) 2. Sample Calculation 98 _ Kl.O - 1) x 7.48 ug/m3] + 7.48 Ug/m3 7.6 x 10~2 IV. OCEAN DISPOSAL Based on the recommendations of the experts at the OWRS meetings (April-May, 1984), an assessment of this reuse/disposal option is not being conducted at this time. The U.S. EPA reserves the right to conduct such an assessment for this option in the future. A-2 ------- |