U.S. ENVIRONMENTAL PROTECTION AGENCY 40 CFR PART 503 STANDARDS FOR THE USE AND DISPOSAL OF SEWAGE SLUDGE

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1 U.S. ENVIRONMENTAL PROTECTION AGENCY 40 CFR PART 503 STANDARDS FOR THE USE AND DISPOSAL OF SEWAGE SLUDGE

Nationwide volume doubled between 1972-1990 largely

2 Sewage Sludge (aka Biosolids) Solids resulting from the treatment of municipal sanitary sewage. Nationwide volume doubled between largely because of implementation of biological treatment and phosphorus removal.

3 40 CFR, Part 503 Clean Water Act enacted Sewage Sludge requirement added Part 503 Final Rule Incineration Landfilling Land Application

4 Incineration/Landfilling Incineration posed significantly more aggregate populational carcinogenic risk than other use or disposal methods Under the Resource Conservation and Recovery Act (RCRA), Subtitle D (non-hazardous wastes), the Agency sets standards to protect human health and the environment based on the reasonable probability that municipal solid waste landfills will cause adverse effects.

5 Focus on Land Application Michigan is currently seeking delegation of the land application portion of 503 from EPA but is not seeking delegation of landfilling and incineration portions of 503

6 Land Application Human Health and Environmental Advantages Direct Benefits - Improved the productivity of land using the soil conditioning properties and nutrient content of sewage sludge Secondary Benefits - 1. Reduction in the adverse human health effects of incineration. 2. Reduction in fuel or energy costs associated with incineration. 3. Decreased dependence on chemical fertilizers 4. Reduction in the emissions associated with incineration that may contribute to the "greenhouse effect"

7 Liability under the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA). Sludge placed on the land for beneficial purposes and applied in compliance with the requirements for land application of sewage sludge provided in 40 CFR part 503, and in accordance with accepted agricultural practices using appropriate application rates, which constitutes the normal application of fertilizer, does not constitute a "release."

8 Other Statutes Regulatory approach and limits developed under one statute may not be appropriate for those developed under another statute. Statutes considered in 503 development: Safe Drinking Water Act Federal Insecticide, Fungicide, and Rodenticide Act Toxic Substances Control Act Resource Conservation and Recovery Act

9 Environmental Profiles Additional information gathered on 50 pollutants of the original 200 identified toxicity persistence means of transport environmental fate frequency of concentration in sewage sludge mechanisms that bind the pollutants

10 Impact Assessment Evaluation of potential for each pollutant to adversely affect human health or the environment. Use of screening models and calculations to predict the concentration of a pollutant that would occur in surface or ground water, soil, air, or food. Compared the predicted concentration of each with established Agency human health criterion. (EPA assumed conditions that would maximize the pollutant exposure of an individual, animal, or a plant, as well as the worst possible pollutant-related effects.)

11 Groundwater Groundwater monitoring and non-degradation policy at field sites is not justified or necessary. Fundamental regulatory principle of Part 503 is prevention of environmental harm. different from approach taken in the "Solid Waste Disposal Facility Criteria" 40 CFR Part 258 Pollution prevention objective monitor the quality of sewage sludge before land application Apply on agricultural land at same rate as a fertilizer. Potential impact of sludge should be similar to or less than fertilizer.

12 Numerical Pollutant Standards Were developed for pollutants "which, on the basis of available information on their toxicity, persistence, concentration, mobility, or potential for exposure, may be present in sewage sludge in concentrations which may adversely affect public health or the environment."

13 Pollutant Limits For land application, pollutant limits in Rule 503 were set, along with management practices, to protect health and the environment for: Arsenic Cadmium Chromium Copper Lead Mercury Molybdenum Nickel Selenium Zinc EPA also evaluated risks associated with organic pollutants and other inorganic pollutants and concluded that numerical pollutant limits for those pollutants are not required

14 Exposure Assessment Pathways and Risk Management Issues Evaluated for the Final Part 503 Rule Numerical pollutant limits to be protective of Highly Exposed Individual (HEI). Part 503 regulations control sludge quality before it is used or disposed of Maximum Contaminant Level (MCL)s or other health-based standards used in the exposure pathway assessment required no additional margin of safety Sufficient margin of safety provided by parameters and assumptions used in the pathway to protect against worst-case conditions.

15 Land Application Risk Assessment Multimedia risk assessment reviewed and approved by EPA s Science Advisory Board and Peer Review Committee. For sewage sludge applied to land, EPA selected a cancer risk level of 1x10-4. That level was selected because the aggregate risk assessment did not indicate significant cancer risk from the practice even in the absence of regulation. For all pathways except 3, duration of exposure is assumed to be 70 years.

16 Land Application Risk Assessment Fourteen exposure pathways evaluated: 1. Consumption of commercially grown crops by the general population. Assumption : 2.5 percent of the total vegetable, fruit and grain diet is grown on sludge-amended soils. 2. Consumption of home-grown crops by home gardeners. Assumptions: 37 percent of potatoes 58 percent of vegetables.43 percent of flour and cereal in the diet are grown on sludge- amended soils.

17 Land Application Risk Assessment Pathways Continued Direct ingestion of sludge by children. 3. Assumptions: Sludge is not diluted with soil. Ingestion rate of.2 g (dry weight)/day. Ingestion continues for five years.

18 Land Application Risk Assessment Pathways Continued HEI consuming meat and dairy products from animals consuming forage raised on sludge- amended soils. Assumptions: Farm household with daily intake of meat and dairy products. HEI also exposed to background intake of pollutants.

19 Land Application Risk Assessment Pathways Continued Similar to pathway four. HEI consuming meat and dairy products from animals ingesting sludge directly while grazing on sludge-amended soils. Assumptions: Sludge is not diluted with soil. 2.5 percent of animal diet is sludge. HEI also exposed to background intake of pollutants.

20 Land Application Risk Assessment Pathways Continued Not a human exposure pathway. HEI is a herbivore consuming plants grown on sludge-amended soil. 7. Not a human exposure pathway. HEI is grazing livestock directly ingesting sludge. Assumptions: Fresh sludge no time for dissipation of organic chemicals. 1.5 percent of diet is sludge. HEI also exposed to background intake of pollutants.

21 Land Application Risk Assessment Pathways Continued Not a human exposure pathway. The effects of pollutants in sludge on the growth of plants were evaluated. 9. Not a human exposure pathway. The effects of copper in sludge on soil organisms were evaluated. 10. Not a human exposure pathway. The effects of cadmium, lead, and PCB s on predators of soil organisms were evaluated.

22 Land Application Risk Assessment Pathways Continued HEI is tractor driver inhaling sludge as dust particles suspended in air by tilling dewatered sludge into the soil. Assumptions: Distance from the driver to the soil surface is one meter.

23 Land Application Risk Assessment Pathways Continued HEI is an individual who consumes fish and drinks water from surface waters that are contaminated with pollutants eroded from sludge-amended soils. Assumptions: HEI eats.04kg/day of fish, drinks 2 liters of water per day. 8.5 metric tons of soil per hectare lost annually to erosion.

24 Land Application Risk Assessment Pathways Continued Inhalation of volatilized pollutants from sludge- amended soil. Assumptions: HEI lives at the boundary of sludge application area. The HEI is downwind from the sludge application area and the wind never changes direction. The HEI breathes 20 m 3 /day of air contaminated with pollutants.

25 Land Application Risk Assessment Pathways Continued HEI is an individual who obtains drinking water from wells contaminated with pollutants leaching to groundwater from sludge-amended soil. Assumptions: Sludge applied for 20 consecutive years. Sandy soil, porosity 0.4. Water table at 1 meter from soil surface. Well located directly below a field with sludge application. 300 year simulation period.

26 Pathogens in Biosolids Bacteria Viruses Protozoa Helminths

27 Some bacterial pathogens of concern in biosolids are Salmonella, Campylobacter, and Shigella. Viral pathogens of concern in biosolids include Hepatitis A, Norwalk, Rotaviruses, and Coxsackie virus. Protozoa of most concern in biosolids are Cryptosporidium and Giardia. Helminths most commonly encountered in the public health arena are hookworms, roundworms, tapeworms, and whipworms.

28 Infectious Disease Three conditions are necessary to produce infectious disease: 1) The disease agent must be present in sufficient concentrations to be infectious. 2) Susceptible individuals must come in contact with the agent in a manner that causes infection. 3) The agent must be able to overcome the physical and immunological barriers of the individual. The Part 503 regulation protects public health by limiting the potential for public exposure to pathogens.

29 Biosolids Quality Not all biosolids are of the same quality. Part 503 breaks down biosolids pathogen reduction into two categories. Restrictions on handling, site access, and other measures are based on this classification system.

30 Class A - reduced level of pathogenic organisms in the biosolids to a level that does not pose a risk of infectious disease transmission through casual contact or ingestion. Biosolids that are to be generally marketed at retail or otherwise distributed for individual home use, must be Class A. A good example would be biosolids composted at 55 degrees C or higher for specified timeframes.

31 Class B - The level of pathogenic organisms is significantly reduced, but pathogens are still present. Most biosolids applied to land in Michigan are treated to meet class B standards. 174 Cities, villages, and townships in Michigan applied biosolids to land in Four were class A, the remainder, Class B.

32 Site and Crop Restrictions The goal of site restrictions is to limit site activities such as harvesting and grazing until pathogens have been reduced by environmental conditions such as heat, sunlight, desiccation, and competition from other microorganisms. Root Crops (potatoes, carrots) 38 months Crops where edible portion touches soil (cucumbers, melons, squash) - 14 months Animal grazing 30 days

33 DEQ Role Review monitoring data on fields and sewage sludge. Collect sludge samples from several facilities per year and analyze them at DEQ lab for quality assurance purposes. Inspect facilities and land application fields. Announced and unannounced inspections.

34 DEQ Role Continued... Provide guidance and information to facility operators, contractors, farmers, and general public. Enforce the laws and promulgated rules of the state. Six district staff, three central office staff, and one position in Department of Agriculture.

35 Conclusion... Quality assurance through MDEQ assistance/oversight Permitting Monitoring Compliance Visit the Biosolids page at Select water

Risk Assessment 10/18/2012. Methodology Overview. Incineration. Disposal in biosolids lagoons (i.e., surface disposal units)

Risk Assessment 10/18/2012. Methodology Overview. Incineration. Disposal in biosolids lagoons (i.e., surface disposal units) Risk Assessment Methodology Overview EPA Guide to Biosolids Risk Assessment Incineration applying science & technology to protect water quality Rhonda L. Bowen Biosolids Manager Hampton Roads Sanitation