EPA risk assessment in this and all other issues is based on the assumption that there is no threshold for increased risk of cancer for those substances that are known to be carcinogens, but that this is not true for non cancer health effects. In the judgment of the author, this latter USEPA, 2003d 43 hypothesis is clearly not true in at least some cases, and leads to a significant underestimation of the importance of non cancer health effects. The example of lead toxicity is a case in point. There is increasing evidence that there is no threshold for the hazardous effects of lead, especially considering neurobehavioral effects in the developing human ( Canfield et al., 2003). As with many toxicants lead affects multiple organ systems, probably by totally independent mechanisms. Thus, lead causes anemia ( Schwartz et al., 1990), elevation of blood pressure ( Nash et al., 2003), interferes with reproduction ( Apostoli et al., 1998) and alters immune function ( Kuo et all., 2001). Many other toxicants, both inorganic and organic, cause similar effects, and a major question remains as to what are the interactions upon exposure to more than one contaminate ( Carpenter et al., 2002).

It is true that non cancer endpoints are often more difficult to document, especially those endpoints that relate to neurobehavioral function or subtle changes in the immune or endocrine systems. However, there is no justification for the assumption that these endpoints have a threshold below which there is no harm. The recent studies of Schell et al. ( 2002) on thyroid function of Native Ameirican adolescents are another example. These investigators found that while serum levels of polychlorinated biphenyls ( PCBs) in these individuals ages 10 16 was low ( mean 1.81, maximum 4.74 ppb), there was a direct linear relationship with thyrotropin stimulating hormone ( TSH), and a linear inverse relationship with free and total thyroxine ( T4) levels. While the perturbation of TSH and T4 were not outside of the range that are usually considered to be abnormal, these observations demonstrate that PCBs alter physiologic function at serum concentrations that are average background levels in the general population.

Response The issues that this commenter raises are scientific policy and risk management in nature. EPA uses peer reviewed human health benchmarks from IRIS or OPP as scientifically appropriate end points in human health risk assessments. EPA risk management policies allow individual EPA programs to establish acceptable incremental target cancer risk levels in the crafting of protective human health standards. In conducting its exposure and hazard screen, EPA has chosen a risk level of 10 5 for the farm family. See section VIII of the notice for a more detailed discussion of this issue.

Comments of Dr. Peter L. deFur Risk Assessment Issues NRC noted a number of areas in which the 1989 risk assessment no longer meets the standards of practice in EPA in 2003. The present comments note the following areas that need to be addressed and are not now in the 503 rule as practiced or proposed  these items need to be evaluated in the new rule revisions.

1) Failure to consider multiple pathway exposures is a common problem in risk assessments, although revisions and newer procedures attempt to remedy this situation. At present, the sludge rule has only limited consideration of multiple pathway exposures. This problem needs to be corrected by evaluating exposures to chemicals from all possible pathways ( air, water, soil, food, dermal contact, recreational contact) in single scenarios, rather than in separated scenarios. This approach will more closely approximate the more highly exposed individuals. USEPA, 2003d 44 2) There is no evidence that EPA considered the fetus in the assessment of risks from chemicals and pathogens in sewage sludge. This omission is quite significant, as the developing fetus is more sensitive to a number of toxic chemicals ( see NRC, 2000). As a cornpanion problem, even if EPA considers the fetus or young children in this rule, the toxicity reference data are not determined for, nor set to protect either young children or fetuses in the IRIS listings. Congress recognized this problem in the Food Quality Protection Act of 1996 when EPA was instructed to use a ten fold ( 10X) safety factor for children's health protection in setting pesticide tolerances in the absence of specific data. EPA can follow this model in the 503 rule.

3) No synergies or other interactions were included even in the same pathways single chemical/ single pathway exposures were considered for the most part. There were some multiple pathway exposures, but none that captured the full range of exposure conditions.

4) In addition, several of the risk assessment assumptions or conditions were not appropriate. The NIOSH and ACGIH standards for inhalation were developed for healthy adults in occupational settings, not residential and should not be applied to residential exposure scenarios. Residential exposures must account for infirm, elderly and infant exposures. No adjustment was made for the conditions in residential exposures compared with occupational ones.

5) The risk assessment conditions did not indicate any consideration for the existing body burdens of many chemicals. As shown in the CDC ( 2003) data on tissue levels of contaminants, the average human carries a substantial body burden of many of these chemicals, and these existing doses have to be counted in conducting a risk assessment.

6) EPA conducted the risk assessment for a highly exposed person, but it is not clear that EPA adjusted for highly sensitive or susceptible persons, especially the fetus. Fetal exposure is often the most dangerous, as noted for lead ( see CDC web site on lead exposure) in people. A number of investigations on PCBs have revealed as much for this group of chemical contaminants as well.

7) EPA continues to have serious regulatory issues concerning the group of chemicals known as dioxins, or more properly, 2,3,7,8, tetrachlorodibenzo p dioxin ( TCDD) and the other chlorinated dioxins, as well as the furans, PCBs and some other chemicals, that act through the same mechanism of action. EPA determined a cancer slope factor for TCDD, and a cancer classification, although the compound is not formally listed in the IRIS database. The National Toxicology Program lists TCDD as a human carcinogen ( NTP 2001). EPA also determined an RfD for TCDD and used this RfD in the water quality criteria process. EPA also undertook a reassessment of the risks ofdioxin exposure in 1991, yet has not completed the reassessment and published the outcome. Thus, the most recent official positions of the agency remain woefully out of date, pending the completion and official publication of the Dioxin Reassessment.

Both the cancer slope factor ( CSF) and the RfD for TCDD are addressed by EPA in the latest dioxin reassessment, the latest draft is on line as of the year 2000. EPA does have a CSF for dioxin  1.5 x 106 per mg/ kg/ day, although the latest draft of the dioxin reassessment calculates an increase of about 6 fold. This matter may be resolved through means other than the reassessment USEPA, 2003d 45 because the NTP listed dioxin as a known carcinogen. In the interim, EPA should at minimum calculate the sludge risk from dioxin based on both cancer slope factors.

The issue with non cancer effects is less straightforward. The dioxin reassessment states that the agency cannot determine an RfD at this time because the US population at present has an average exposure ( also an average body burden) that exceeds the RfD ( supposedly a " safe " dose). Nonetheless, the last RfD of 1.0 pg/ kg/ day was used by EPA in the risk assessment for the cleanup of the Times Beach Superfund site. EPA needs to take some consistent and meaningful steps to reduce dioxin formation and exposures, as recently noted by the NRC ( 2003) publication on dioxin exposures. EPA has faced a similar situation previously when in the 1970s the US population was overexposed to lead. In that case, EPA could not, and still does not estimate an RfD. Nonetheless, EPA moved to identify sources and exposures of lead, and eliminate or reduce those exposures. A similar approach is called for in the case of TCDD and related compounds.

All of these areas require attention in the new 503 rule, along with evaluation of many organic chemicals and some additional metals.

Response EPA believes that the elements ( human health benchmarks, pathways of exposure, conceptual site models, definition of the highly exposed individual ( HEI), default values used in the model equations) of Part 503 risk assessments are appropriately conservative to protect public health from pollutants in sewage sludge with an adequate margin of safety.

For the Round One pollutants, an individual exposure pathway was the predominant exposure pathway for either human health or ecological effects. Summing all exposure pathways would have made little difference on EPA's overall risk characterization for these metallic pollutants. For the risk assessment that was utilized on dioxins in Round Two of the Part 503 Standards, dioxin exposure to the HEI for individual exposure pathways was summed.

The human health benchmarks chosen from IRIS or OPP take into full consideration sensitive life stages of humans such as the fetus and infants. Please see also EPA responses to Comment Log No. 51 of this section.

With respect to the comments on dioxins, see 68 Fed. Reg. 61084 published on October 24, 2003, which announced that the Agency would not be regulating dioxins in land applied sewage sludge.

Municipal Wastewater Treatment Plants EPA Log # 14: Metro Wastewater Reclamation District Comment The Metro District supports EPA's plans to reassess pollutant exposure pathways and risk calculations. Any reevaluation of the pollutant limitations included in the current Part 503 regulations should involve the most current exposure and toxicity information. The same procedures should be applied in the evaluation of any additional pollutants selected through the USEPA, 2003d 46 targeted survey evaluation process. The District encourages the EPA not to rely too heavily on the probabilistic or computer modeling approaches in the risk assessment process. To be useful, modeling results require some type of verification or validation. Verification of potential adverse effects of trace amounts of pollutants to human health or the environment can take years, if not decades, of data collection. However, when coupled with the more traditional deterministic approach, modeling results can be a useful screening tool to support findings related to potential adverse impacts.

One of the most challenging recommendations of the NRC report concerns potential effects of biosolids on human health. The NRC has recommended that EPA conduct comprehensive studies to determine if land application of biosolids has affected biosolids workers or nearby residents. The Metro District agrees with the NRC and EPA that comprehensive epidemiological studies are complex, time consuming, and require substantial funding. EPA has proposed a strategy that focuses on short term, focused human health studies that could provide insight into whether or not longer term epidemiological human health studies are warranted. The District agrees with this approach. Short term studies, coupled with development of new and improved analytical testing methods, can provide important first phase information to determine if more in depth epidemiological studies are needed. Improved research methods, especially for recovery of pathogens from wind blown soil/ biosolids mixtures, would be crucial to the success of any epidemiological studies that attempt to correlate the presence of pathogenic microorganisms in biosolids with suspected diseases in humans or animals.

Response EPA agrees with these comments.

EPA Log # 47: Miami Dade County Water and Sewer Department ( MDWASD)

Comment Evaluating the State of Science and the Risk Assessment methodologies is also very important. MDWASD agrees with conducting further research in order to review the Risk Assessment methodologies. We support the in depth studies and review being conducted by the WERF and other research organizations. Throughout this research and review process, it is very important to involve the Stakeholders.

MDWASD commends the EPA for recognizing the need for further review and studies prior to changing the existing regulations.

Response EPA agrees with these comments.

Land Application Company EPA Log # 26: Synagro Technologies, Inc.

Comment USE IMPROVED RISK ASSESSMENT METHODS TO ESTABLISH BETTER STANDARDS FOR CHEMICALS AND PATHOGENS. USEPA, 2003d 47 State of the Art Chemical Risk Assessment The expert panel correctly pointed out that advances in risk assessment methods have occurred in the decade since the Part 503 Round I regulations were promulgated. As expected, such advances have been achieved by the research initiatives undertaken by the proper branches of EPA. The Office of Water ( OW) is a " consumer user" of these methods, not a " developer" of such methods. That is why any effort undertaken by OW should first be to examine the state of the art already advanced within the Agency.

A key example is the new probabilistic risk assessment for dioxin and dioxin like substances in the Part 503 Round II regulation Notice of Data Availability ( NODA) published by EPA in June 2002. The July 2002 release of the Report and the NODA appearing in the Federal Register in June 2002 were so close in timing that the expert panel did not have the benefit of reviewing how one of their recommendations ( conduct a modern chemical risk assessment for land applied biosolids) was already in process. EPA should seriously consider that among the persistent, bioaccumulative toxics ( PBT) of interest, dioxin and dioxin like compounds are domestically and internationally considered t he most important potential health threats to the general population. Since the NODA characterized the threat from these highly toxic substances as both low and remote, using unrealistically conservative and exaggerated risk assumptions, it is questionable why the Agency would devote significant resources to investigate chemicals of lower human toxicity. EPA should consider the following factors in deciding how much effort should go into developing new chemical risk assessments.

° Some elements of the Report are most properly handled by ORD/ NCEA on a chemical specific basis. Some of the recommendations regarding updating the 503 Rule risk assessment are being made by NCEA as it conducts its periodic reviews of IRIS. OW should utilize work done by NCEA and should not be responsible for risk assessment developments in this area.

° There may not be significant gains in re calculating risks. For example, a re calculation of the arsenic limit using currently available risk assessment methodology yields a result of 46 ppm compared to 41 ppm in the 503 Rule. This difference is too small to be significant.

° EPA has developed risk assessment technology in other programs that can be used with little modification to evaluate new chemicals or re evaluate old chemicals found in biosolids. EPA's 1998 Methodology for Assessing Health Risks Associated with Multiple Pathways of Exposure to Combustor Emissions ( EPA 600/ R 98/ 137) (" Combustion Guidance"), for example, can be readily adapted to assess biosolids risks for a variety of pathways and receptors. Since this methodology has already been through extensive peer review and public comment, it should be readily acceptable to both the regulated community and the public.

° Risk assessments should be focused. Many chemicals do not need to be evaluated in a risk assessment for a variety of reasons: o Concentrations are too low for example, cadmium concentrations have dropped significantly due to operation of pretreatment programs. Current cadmium concentrations in biosolids are well below Soil Screening Levels for ingestion by either residents or outdoor workers; thus it is USEPA, 2003d 48 unlikely that cadmium associated with biosolids would present an unacceptable risk. Screening tools such as SSLs should be used to eliminate chemicals as appropriate. o Many chemicals are too biodegradable to be of significance in biosolids. For example, alkylphenols degrade so rapidly in biosolids that a risk assessment would likely not be meaningful, especially in the contingent management context where setbacks, use and access restrictions are required. o New or emerging chemicals can be dealt with using focused risk assessments in a rapid and cost effective fashion. For example, a risk assessment of PBDE's using readily available analytical data was conducted in less than two person weeks using existing risk assessment technology. This risk assessment was conducted using minor modifications to the Combustion Guidance in addition to existing reference doses from IRIS and physicochemical properties readily available in the scientific literature.

The NAS/ NRC report recommended EPA use improved risk assessment technologies. EPA plans to reassess its risk assessment methodologies and apply new methodologies to key pollutants and pathways that are likely to be of greatest concern or where new scientific information has the greatest impact.

° EPA's definitions of stakeholders in this section appear to exclude industry.

° EPA refers to " state of the science" and " most up to date" scientific information and risk assessment technologies. EPA should only rely on peer reviewed and generally accepted information and methodologies and not innovative techniques that may not be reliable. EPA is required to ensure that any results of a new or " developing" risk assessment has full peer review in order to comply with the Data Quality Act.

° There were a lot of problems with the Round Two risk assessment that should be mentioned.

° EPA should make biosolids risk assessments consistent with other risk assessments performed throughout the Agency.

Response Please see EPA's response to Comment Log Nos. 51 and 43 Peter Defur in this section with respect to chemical pollutant risk assessments. With respect to pathogen risk assessments, please see the EPA response to Comment Log No. 37 in this section.

State of the Art Quantitative Microbiological Risk Assessments EPA should consider the following factors in regard to pathogen risk assessment efforts.

° EPA should not undertake quantitative microbiological risk assessments ( QMRA) unless it has developed and published a peer reviewed guidance document that has SAB approval. Anything less would not comply with the Data Quality Act.

° Quantitative microbial risk assessment ( QMRA) is a relatively new tool that has neither a history of use in rule making nor the degree of validation necessary to ensure its reliability. The elements USEPA, 2003d 49 of a QMRA are similar to those of a chemical risk assessment. QMRA requires problem formulation, exposure analysis, pathogen occurrence analysis, evaluation of potential health effects and the dose response relationship and the combination of this information in a risk characterization.

° The development of the Part 503 Rule, Round I, used pathogen risk assessment data although not in the current QMRA framework. For example, pathogen identification, enumeration, treatability, virulence, and persistence were all studied by EPA. The Part 503 rule requires a high level of pathogen reduction ( based upon a 2 log reduction or at least 99% removal) coupled with site restrictions, which are based upon the worse case survival times for pathogens. This is risk assessment and is more than adequate to protect human health as proven by the absence of documented health effects among biosolids workers, wastewater treatment plant operators and the general public.

° The Report did not consider readily available information regarding pathogen risk assessments. For example, EPA's 1995. Pathogen Risk Assessment Methodology for Municipal Sewage Sludge Landfilling and Surface Disposal ( EPA/ 600/ R 95/ 016) was not cited in the report, nor was Bitton's Wastewater Microbiology.

° The large amount of available information, including that not considered in the Report, is probably sufficient to put into the current QMRA framework in a contingent management context.

° Extreme caution must be taken in using many studies of environmental pathogens. Existing pathogen measurement science is not as reliable as chemical analyses. Problems exist with detection limits, species identification, quality assurance/ quality cont rol, and background levels which all need to be considered.

The NAS/ NRC report recommended that EPA develop and standardize methods for measuring pathogens and emerging chemicals in biosolids and bioaerosols. EPA already has ongoing and planned research in these areas.

° Fourier Transform Infrared ( FTIR) spectrometry techniques should be validated and quality assured prior to use at land application sites.

° EPA needs to carefully consider contribution of naturally occurring background to airborne microorganism concentrations. Pattern recognition techniques such as principal components analysis or cluster analysis should be evaluated for this purpose.

° EPA should consider methods developed by consensus organizations such as " Standard Methods" and ASTM standard methods.

Response With respect to pathogen risk assessments, please see the EPA response to Comment Log No. 37 in this section. USEPA, 2003d 50 Chemical and Pathogen Risk Assessment and Contingent Management The NAS/ NRC panel recommendations are seriously flawed because they viewed biosolids land application primarily from a theoretical perspective, and they essentially ignored that the practice is already heavily regulated. EPA needs to set the record straight on this and make the point that the entire regulatory framework of biosolids management needs to be considered before any additional risk or health studies are undertaken. The practice of biosolids land application is a contingent management activity, meaning, in part, that limits, restrictions and prohibitions apply via federal and state/ local regulation. Any realistic chemical or pathogen risk assessment should take these contingent management requirements into consideration as inputs into the model.

° Biosolids beneficial recycling is not an " unregulated" activity. The safe beneficial use of biosolids is contingent on application of a comprehensive framework including regulations contained in the Clean Water Act ( CWA), Resource Conservation and Recovery Act ( RCRA), Federal Insecticide Fungicide and Rodenticide Act/ Food Quality Protection Act ( FIFRA/ FQPA), Toxic Substances Control Act ( TSCA), state and local statutes and regulations, and industry practices ranging from the Responsible Care of the chemical industry to the management practices of the National Biosolids Partnership. It is not possible to fully understand the environmental context of biosolids generation and use without considering this entire framework.

° Although risk assessments and health studies are important, they are only one component of biosolids management t hat ensures health and safety of land application. The NAS/ NRC Report did not consider the other components, but rather only focused on risk assessments and health studies. Other significant components include:

o Technology based standards. Technology based standards for pathogen control are a keystone of biosolids regulation. This topic was given short shrift in the Report ( pp 202 205), despite the large amount of literature and operating data on this subject. Technology based standards are a viable alternative to risk based standards. Other environmental regulatory programs ( e. g. MACT under the Clean Air Act) function well using health protective technology based standards while risk assessments are being developed. The parallel between the CAA MACT rule and the 503 Rule should be further explored and utilized should additional biosolids risk assessment be required. It is possible that additional biosolids risk assessment may be useful in the limited context of demonstrating t he safety of t he existing technology based standards of the 503 Rule. o Management Practices include the Code of Good Practice, National Manual of Good Practice, EMS Guidance, and EMS verification. By encouraging the use of management practices, a degree of environmental protection over and above that afforded by regulatory compliance may be attained. o Institutional controls include the land use restrictions in the 503 Rule in addition to state and local controls such as setbacks. Both of these are designed to limit exposure pathways or to allow time for both chemicals and pathogens to be detoxified by natural attenuation before exposure might occur.

° Not only are these elements of contingent management important for the overall assurance of safe biosolids practices, but they should also be incorporated into any risk assessment that may be USEPA, 2003d 51 performed in the future. For example, setbacks, land use restrictions, and sediment control best management practices that are currently required should be used as inputs to risk assessment scenarios.

The NAS/ NRC report recommended that EPA evaluate measurement and risk assessment techniques for removing perceived uncertainties regarding pathogens. EPA is proposing pathogen research in several areas.

° Technology/ management based approaches are still valid and shouldn't be abandoned.

° The relationship between odor and health effects is not established, is controversial and affects federal agencies other than EPA. It should be dealt with elsewhere.

° The PEC should be the main instrument for dealing with pathogens.

° EPA should probably take no action regarding pathogens until the WERF and NSF WQC research is finished.

° QMRA cuts across federal agencies. For example, FDA and CDC may rely on QMRA for activities totally unrelated to biosolids. QMRA is probably best dealt with via an interagency effort rather than in the context of biosolids research.

Response EPA agrees in general with these comments. The efficacy of sewage sludge land application regulations is based to a large extent on the extent of overlapping regulation at the Federal, State, and local levels and the resultant overlapping regulatory oversight of sewage sludge land application projects.

Association EPA Log # 30: Tri TAC Comment Risk Assessments Tri TAC supports EPA's plans to address the potential health hazards and exposures associated with land application of biosolids using state of the science risk assessment approaches. Tri TAC strongly encourages EPA to consider how representative stakeholders could be included in the risk assessment process to help identify exposure pathways, local conditions that could influence exposure, and possible adverse health outcomes.

Tri TAC understands that EPA plans to " use the Round Two risk assessment approach [ a probabilistic approach] as a starting point for evaluating the NRC's recommendations, including the use of the reasonable maximum exposed ( RME) individual" for improving risk assessments in future rulemakings. Tri TAC cautions EPA to ensure that the probabilistic approach is consistent with EPA risk assessment policy and sufficiently validated to support future regulatory decisions. EPA should consider whether the probabilistic approach should be used only as a screening tool USEPA, 2003d 52 and whether it may need to be coupled with the more traditional deterministic approach in some applications.

Tri TAC further understands that the EPA's use of a risk assessment framework or paradigm to provide a focused reassessment of certain previously addressed pollutant risks, exposure pathways and risk assessment approaches, as well as an assessment of pollutants which have not been previously evaluated, may result in updates to the Round 1 risk assessment models and reevaluations of selected pollutants. Tri TAC would support any such reevaluations of, or updates to, the " science" associated with these earlier rulemakings to the extent that EPA's problem formulation process identifies them as priority areas.

Tri TAC suggests that EPA's efforts to understand the potential risks associated with biosolids focus primarily on those areas where there are perceived weaknesses in the current regulations, specifically pathogens in biosolids and bioaerosols.

Response See EPA responses to Comment Log Nos. 51 and 43 Peter Defur.

EPA Log # 27: California Farm Bureau Federation Comment The USEPA must reevaluate its land application assumptions; " real world" biosolids application rates greatly exceed what the USEPA presumed when it developed its regulations.

In its risk assessment, the USEPA assumed that the typical annual sludge application rate for agricultural land based on crop nutrient requirements would be 7 metric tons/ hectare ( approximately 3 tons/ acre). 24 As the D. C. Circuit Court of Appeals, in Leather Industries of America, Inc. v. Environmental Protection Agency, et al., 40 F. 3d 392, 396 ( 1994), described it, the USEPA developed the eight ( formerly ten) regulated metals concentration limits:

" By applying certain conservative assumptions" about the amount of sludge that would be applied to a given area of land, the EPA " backcalculated" from the total pollutant limits in a given area of land to a permissible sludge pollutant concentration per load. 58 Fed. Reg. 9317. The " backcalculation" provides the EPA a means of converting the cumulative pollutant limit into a concentration cap for the pollutant in any given load of sludge. The model assumes a total amount of sludge that will be applied to a given hectare of land based on an assumed yearly application rate and assumed duration of application. The EPA assumed that ten metric tons of sludge would be applied annually to a hectare of land for100 years. This converts into an assumption that, in total, 1000 metric tons of sludge will be applied to a given hectare of land. Based on ( 1) this total amount of sludge that the EPA assumed would accumulate on an area of land, and ( 2) the total amount of pollutant that the EPA had determined could safely accumulate on an area of land, the EPA calculated pollutant/ sludge, the permissible concentration of pollutant in any application of sludge. ( internal citations omitted)

Converting units from metric tons/ hectare to tons/ acre, it is evident the USEPA, in developing its metals concentration limits, assumed: ( 1) that annual sewage sludge applications at a particular USEPA, 2003d 53 site would be limited to approximately 4.4 tons/ acre; and ( 2) that the total lifetime accumulation of sewage sludge at a particular site would not exceed 440 tons/ acre. Yet, in California, annual biosolids applications may reach 10 40 dry tons/ acre. 25 On this basis, use of the USEPA's metals concentration limits may underestimate metals accumulation rates by a factor of ten ( 10) or more.

Further, application rates of 10 40 tons/ acre would mean that the USEPA's assumed lifetime accumulation of sewage sludge at a particular site could be reached within 10 11 years, not 100 years. This negates claims that we need not worry about the possible harmful buildup of metals concentrations in soils at application sites, since it may take only 10 years ( a very realistic time frame) for typical applications to cause the total accumulation of sewage sludge at a particular site to exceed the maximum amount the USEPA assumed would be deposited there. 26 Considering that farmers generally intend to continue farming for many years, and pass their farms on to their children, this is a frightening prospect that justifies the adoption of more conservative metals concentration limits and application rates.

Response See EPA responses to Comment Log Nos. 51 and 43.

EPA Log # 50: Water Environment Federation ( WEF)

Comment Context and Risk Communication   To some, the existence of detailed studies and risk assessments of biosolids imply that they are dangerous; to others, " exposure equals risk." To address these erroneous reactions, EPA needs to follow through on its commitment to improve risk communication. One way for EPA to accomplish this goal may be to provide a context for the information that will aid people's understanding. For example, EPA should consider presenting biosolids information as a comparison between biosolids and other materials used in a similar manner, like manures or chemical fertilizers, which are more familiar to the public.

C. Risk Assessment WEF endorses the approach EPA proposed, most specifically the reassessment of previously evaluated pollutants ( in light of new data and approaches), the assessment of new pollutants based upon state of the art approaches, the inclusion of stakeholders in the risk assessment process, and collaboration with USDA and others. The two step process outlined by EPA that will ultimately result in a prioritized list for risk assessment activities is logical and should result in maximum value to the public.

Response See EPA responses to Comment Log Nos. 51 and 43.

EPA Log # 46: Association of Metropolitan Sewerage Agencies ( AMSA)

Comment Risk Assessments AMSA supports EPA's plans to address the potential health hazards and exposures associated with land application of biosolids using state of the science risk assessment approaches. AMSA strongly encourages the Agency to consider how representative stakeholders could be included in USEPA, 2003d 54 the risk assessment process to help identify exposure pathways, local conditions that could influence exposure, and possible adverse health outcomes.

AMSA understands that EPA plans to " use the Round Two risk assessment approach [ a probabilistic approach] as a starting point for evaluating the NRC's recommendations, including the use of the reasonable maximum exposed ( RME) individual" for improving risk assessments in future rulemakings. AMSA cautions the Agency to ensure that the probabilistic approach is consistent with Agency risk assessment policy and sufficiently validated to support future regulatory decisions. EPA should consider whether the probabilistic approach should be used only as a screening tool and whether it may need to be coupled with the more traditional deterministic approach in some applications.

AMSA further understands that the Agency's use of a risk assessment framework or paradigm to provide a focused reassessment of certain previously addressed pollutant risks, exposure pathways and risk assessment approaches, as well as an assessment of pollutants which have not been previously evaluated, may result in updates to the Round One risk assessment models and reevaluations of selected pollutants. AMSA would support any such reevaluations of, or updates to, the science associated with these earlier rulemakings to the extent that EPA's problem formulation process identifies them as priority areas. AMSA suggests that EPA's efforts to understand the potential risks associated with biosolids focus primarily on those areas where there are perceived weaknesses in the current regulations, specifically pathogens in biosolids and bioaerosols.

Response See EPA responses to Comment Log Nos. 51 and 43.

States EPA Log # 48 and 39 ( duplicates): Wisconsin Department of Natural Resources Comment 10. Section VIII. C. Risk Assessment  The response in this section represents a reasonable approach assuming the actions are actually taken and the recommendations are fulfilled. They must be done.

Response EPA thanks the commenter for the comments. See EPA responses to Comment Log Nos. 51 and 43.

EPA Log # 59: New Jersey Department of Environmental Protection ( NJDEP)

Comment The NRC recommendations included reassessing standards for chemicals currently in the Part 503 regulation. Since there is new information available, the Department believes that it would be prudent to perform a revised multipathway risk assessment with particular attention paid to arsenic, and indirect pathways for mercury. Specifically, the Department supports the NRC recommendations to confirm that the speciation of arsenic and mercury in biosolids are in forms USEPA, 2003d 55 that are less toxic, and that reduced metal bioavailability, than what had been assumed in developing the current standards, in biosolids amended soils is very likely.

Response See EPA responses to Comment Log Nos. 51 and 43. In the Round one Standards, EPA assumed arsenic was in the most prevalent toxic chemical valence state. Analytical data indicate that methyl mercury is an insignificant fraction of total mercury in sewage sludge. The Part 503 Round one numerical standard for mercury is based on the most prevalent and toxic form of mercury, mercuric (+ 2).

TOPIC D. METHODS DEVELOPMENT Academia EPA Log # 51: Ellen Z. Harrison Comment EPA is " considering developing and validating methods for measuring bacteria and virusus." This is a critical need. In reviewing the plans for the PA study, it became clear that existing methods not only for viruses but also for bacteria, are totally inadequate. Data presented to the group showed that samples tested under " approved" Colony Forming Unit ( CFU) methods failed to detect the pathogens, while Most Probable Number ( MPN) methods detected them. If research and regulatory decisions are based only on currently approved methods, we are clearing failing to monitor as needed and we may be failing to protect the public health. There is an urgent need for EPA to work to develop and validate methods for detection and enumeration of bacteria and viruses in sludges, soil, water and air.

Response Project 3 in Section VII B of today's Federal Register notice describes EPA's program for improving the analytical methods for Salmonella, enteric viruses, Ascaris ova and fecal coliforms in sewage sludge within the next three years. EPA fully agrees with the commenter on the importance of this effort.

Citizens EPA Log # 29: Henry J. Staudinger Comment D. EPA's Methods Development Strategy is Not Adequate. NRC Recommends that EPA develop standard methods for measuring pathogens and emerging chemicals in biosolids and bioaerosols to better conduct and interpret future risk assessment.

EPA's strategy is to address this recommendation through studies such as the EPA/ USDA/ DEP project discussed earlier. However, the Pennsylvania project will focus only on a limited number of pollutants and was not designed to focus on pollutants present in biosolids likely to cause adverse health complaints. USEPA, 2003d 56 Response Please see the EPA response to Comment Log No. 51 of this section. In addition, please see Project 10 in Section VII B of today's Federal Register notice entitled Development and Application of Analytical Methods for Detecting Pharmaceutical and Personal Care Products ( PPCPs) in Sewage Sludge.

The purpose of this project is to develop and apply analytical methodologies for detecting pharmaceutical and personal care products ( PPCPs) in sewage sludge. The NRC Report specifically identified PPCPs as one category of diverse compounds that has not been studied in sewage sludge and that is especially likely to be present in domestic sewage sludge. The NRC report indicated that there is a need for a new hazard assessment of sewage sludge to expand the suite of chemicals evaluated.

In FY 2004 through FY 2005, chemical analysis methods developed in house previously for PPCPs ( e. g., antibiotics and musks) would be adapted for sewage sludge. In FY 2006, EPA may finish methods development, convert them to 40 CFR Part 136 methodology, and publish methodologies. Subsequently, the methods may be applied to a limited number of real world samples for a pilot scale survey of PPCPs in sewage sludge.

With respect to other emerging chemicals, EPA has developed analytical methods for certain endocrine disrupting chemicals ( EDC) and is studying the fate and transport of these EDCs in the land application situation, particularly amounts in sewage sludge, degradation following application, transport down the soil column, and runoff into surface waters. Current studies focus on the fate and transport of the specific EDCs: alkyl phenol ethoxylates and steroid hormones.

EPA Log # 37: David A. Burrows Comment On page 17388 of the Federal Register, in the " methods development" section, is stated " EPA is considering developing and validating analytical methods for enteric viruses and helminth ova..." These viruses and ova are human health threats and this work should be done now.

Response Please see the EPA response to Comment Log No. 51 of this section.

EPA Log # 40: Thomas F. Albert Comment Comment # 21: On page 17388 in the section " 2. The Agency's Response to Methods Development" there again seems to be mention of the " 5 site sludge study." Is this the cooperative study in PA by the EPA/ USDA/ PA DEP?

Comment # 22: On page 17388 in the " methods development" section is stated " EPA is considering developing and validating analytical methods for enteric viruses and helminth oval   . " Why just CONSIDER this? Why not DO it? Such viruses and ova are health threats, what health benefit is there by waiting? USEPA, 2003d 57 Response Paragraph one of these comments: Please see the EPA response to the Comment Topic B section of this document. Paragraph two of these comments: Please see the EPA response to Comment Log No. 51 in this section.

EPA Log # 25: Northumberland Association for Progressive Stewardship ( NAPS) Sewage Sludge Study Group Comment D. Methods Development Lines 757 801. We are also pleased that EPA plans to implement the NRC recommendations regarding methods development. But we also believe that methods development will be shallow unless adequate resources are applied to the survey, exposure and risk assessment processes mentioned above.

Response EPA agrees with these comments.

Environmental Groups EPA Log # 43: Natural Resources Defense Council ( NRDC)

Comment NRC recommends that EPA develop and standardize methods for measuring pathogens and developing chemicals in biosolids and bioaerosals. This would also help to ensure that the Agency's management practices and standards are reliable. Specific recommendations include using improved pathogen detection technology, round robin laboratory testing, mechanisms for incorporating new methodologies into the verification process, and measures of performance that can be easily monitored.

Although acknowledging the need for improving exposure assessment methods and treatment processes, EPA proposes to take no action beyond existing studies and projects. Undoubtedly, these ongoing efforts are important to the methods development process, but fall far short of what NRC deems necessary. Completely absent from EPA's self described plans for methods development is any concrete plan to standardize or validate existing methods or to verify that the Agency's management practices and standards are reliable. Instead of developing a system wide approach to improving and standardizing methodology, EPA vaguely references prospective projects that, although beneficial, would continue EPA's piecemeal approach to biosolids methods development.

Response Please see EPA's response to Comment Log Nos. 51 and 29 of this section.

Municipal Wastewater Treatment Plants EPA Log # 14: Metro Wastewater Reclamation District Comment In response to the NRC report's recommendation to develop new and improved analytical test methods, the EPA has proposed a robust plan to evaluate analytical methods for USEPA, 2003d 58 pathogens and chemicals associated with biosolids. The Metro District endorses this plan as a prudent, measured approach to developing better test methods. The District agrees that improved, standardized tests are needed for pathogens in biosolids. Valid risk assessments are predicated upon the availability of accurate data. In addition, studies on any cause effect relationships related to biosolids, land application sites, and community impacts require improved analytical methods to identify pollutants and microorganisms in soil, water, and air.

The Metro District suggests that EPA consider expanding its review to include available but unpublished data on pollutant concentrations at land application sites managed by private contractors or wastewater treatment agencies. For example, such entities may have produced data from " in house" studies. This information could be used to meet EPA's goals related to validation of the management restrictions in the current Part 503 regulations.

Response EPA thanks the commenter for the comments in paragraph one. With respect to paragraph two, EPA will utilize only those data that meet the criteria contained in EPA's Data Quality Guidelines.

Association EPA Log # 30: Tri TAC Comment Methods Development In response to the NRC Report's recommendation to develop new and improved analytical test methods, EPA has outlined its ongoing and planned methods development activities, indicating that it plans to focus resources on pathogens and chemicals associated with biosolids. Tri TAC agrees with the NRC's recommendation and EPA's assessment that validated analytical methods are necessary, for example, to support exposure assessments, for determining the reliability of treatment processes, assaying pathogens and chemicals in raw and treated biosolids, and incident follow up. Valid risk assessments are predicated upon the availability of accurate data. Studies on any cause effect relationships related to biosolids, land application sites, and community impacts require improved analytical methods to identify pollutants and microorganisms in soil, water, and air.

EPA describes recently initiated EPA methods development work including field studies at five biosolids production and application sites. EPA also describes ongoing field studies at animal manure land application sites, composting sites, and concentrated animal feeding operations, which are measuring pathogens, toxic organic compounds, odorants and particulates. In addition to using these field studies on non biosolids land application sites for methods development, Tri TAC encourages EPA to use the information collected from these studies to assess the relative risk posed by biosolids land application and to assess the need for regulations on these other amendments in order to protect human health or the environment.

Response EPA agrees with these comments. USEPA, 2003d 59 EPA Log # 50: Water Environment Federation ( WEF)

Comment D. Methods Development WEF agrees that standardized protocols for the measurement of pathogens, odorants, and emerging chemicals must be performed. At present, it seems that it may be a long time before basic methods for the analyses of some pathogens are available, let alone developed to the point that reproducible, practical methods are accessible to most laboratories. To address potential concerns in the area of pathogen analysis, WEF agrees with the NRC's recommendation that there should be concurrent emphasis on confirming the appropriateness of existing indicator organisms or identifying new ones ( clostridium, for example). The Federation encourages EPA to involve WEF and other clean water professionals in the process to make sure the required methods for measurement can be reasonably achieved.

Response EPA agrees with these comments. Please see the EPA response to Comment Log No. 51. EPA will involve all stakeholders ( the general public, State and local agencies, industry and private groups) as it executes its action plan in response to the NRC recommendations.

EPA Log # 46: Association of Metropolitan Sewerage Agencies ( AMSA)

Comment Methods Development In response to the NRC Report's recommendation to develop new and improved analytical test methods, EPA has outlined its ongoing and planned methods development activities. AMSA agrees with the NRC's recommendation and EPA's assessment that validated analytical methods are necessary, for example, to support exposure assessments, for determining the reliability of treatment processes, assaying pathogens and chemicals in raw and treated biosolids, and incident follow up.

EPA describes recently initiated EPA methods development work including field studies at five biosolids production and application sites. EPA also describes ongoing field studies at animal manure land application sites, composting sites, and concentrated animal feeding operations, which are measuring pathogens, toxic organic compounds, odorants and particulates. In addition to using these field studies on non biosolids land application sites for methods development, AMSA encourages EPA to use the information collected from these studies to assess the relative risk posed by biosolids.

Response EPA agrees with these comments.

Counties EPA Log # 28: Solano County Department of Environmental Management Comment 2. Sampling Methods and Protocols The Solano County DEM recommends that the EPA pursue developing protocols for sampling of biosolids at different treatment plants and within the same treatment plant over time, based on USEPA, 2003d 60 inflow sources to the treatment plant and the treatment processes used at the plant. The intent of such protocols should be to provide a level of credibility to the quality control sampling results so that the chemical, pathogen, and nutrient content found by the sampling can be assured not to be exceeded during periods that the biosolids are not sampled.

Response Responded to in Section One ( Survey) of this document.

States EPA Log # 48 and 39 ( duplicates): Wisconsin Department of Natural Resources Comment11. Section VIII. D. Methods Development  Planned Method Development Activities  It is stated that EPA is " considering" developing and validating analytical methods for enteric viruses and helminth ova. This work must be done because these pathogens are regulated under the federal standards. It is impractical to implement a regulation when methods for analyzing limited constituents does not exist. Funding must be provided to complete this work ( see also comment 6 and 7).

Response EPA agrees with these comments. Please see EPA's response to Comment Log No. 51 in this section of the document. USEPA, 2003d 61 TOPIC E. PATHOGENS Citizens EPA Log # 6: Edward McGowan Comment Below are some comments on why hospitals should be considered as industrial systems needing pretreatment of wastewater. Hospitals are one of the epicenters for multi drug resistance.

What follows discusses hospitals, pathogens in wastewater, their ability to survive the rigors of a treatment works and then their potential to remain in the environment.

Since bacteriophages are able to carry mobile genetic elements, and viruses can recombine, these constitute a worrisome situation. There are some recent reports on polio virus mutating and also picking up genetic elements from wild polio viruses, thus rendering them again neurovirulent. Some papers also suggest that the polio virus can pick up mobile genetic elements from other viruses. If it goes one way, one might also assume the reverse. Thus in addition to the SARS issue, there are other reasons to pressure for better sludge control.

The Hospital and Multi Drug Resistant Bacteria. In the revamping of hospitals to meet new seismic requirements, serious thought should be applied to the make up of sewer effluents. In many industrial settings, there is a requirement for pre treatment. This requirement accrues to the need for protecting receiving waters, hence the health of humans and the environment. Many hospitals should consider whether or not they fall within the category of an industrial wastewater generator.

Amongst the community at large, including sewer treatment plant staff there is a distinct lack of recognition for issues relating to MDRB. These organisms pass from sink or toilet through sewer treatment into the environment at large. Although current water quality standards are silent on such issues, there is a pressing need for recognition. Many hospitals, as members of their communities, need to go beyond current standards. Contrary to popular myth, many pathogens do survive their passage through a sewer treatment plant and thus remain to constitute an increased public health risk. That this situation has continued for some time may be attributed, in part, to economics and the antiquated water quality standards. Nonetheless, readily available scientific and medical literature are, and have been for some time, replete with data demonstrating and confirming this fact. Studies reported in the scientific and medical literature dating back to at least to the 1970s show failure of treatment. Thus, this is hardly new knowledge. [ Fontaine, et al, ( 1976); Grabow, et al. , ( 1973); Linton, et al., ( 1974); Walter et al,. ( 1985)].

Prior to the current situation of wide spread antibiotic resistance, the water quality standards using coliform may have been adequate. The situation is changed. The standards have not. USEPA, 2003d 62 Previous studies have shown that waste effluents from hospitals contain higher levels of antibiotic resistant enteric bacteria than waste effluents derived from other sources [ 1,2,3,4,5,6]. Hospitals are epicenters of MDRB.

In a recent meeting of our task group, one of the members raised the question relating the survival of pathogens once the material has left the treatment works. The essence of the question is related to the survival of genetic material. Hence, analyses on the underlying issue of surviving MDRB. The question went something like this" If Staphyloccus aureus were found dead, did that mean that the problem was solved?" The corollary   was it dead or merely in the viable but non culturable ( VNC) state, a starvation arrested state, or killed from a starvation but otherwise recoverable state by sudden nutrient excess in the culture? Additionally, there are issues of the re uptake of naked DNA.

Recently, in discussing mobile genetic elements ( MGE), Nielsen, et. al. [ 7,8], demonstrated that DNA was well protected in dead cells and that transforming activity remained. The survival of such material was found to be up to two years [ 9]. Additionally, these papers demonstrate that plant rootss could transfer MGEs to bacteria and visa versa. Thus non pathogens and non bacteria can serve as reservoirs for maintaining resistance genes. Pneumococci, for example, can take up naked DNA from the environment ( natural transformation from lysed bacteria). Thus merely finding " dead" bacteria may be no assurance that risk has reached acceptable levels. Further, from the classical work of Griffith, we know that pathogens can regain virulence from dead bacteria.

Additionally, during the above noted meeting, I had mentioned some notes taken at a recent medical grand rounds. The speaker, an expert on infectious disease, indicated that there is strong medical evidence that about one half of the general, non hospital community acquired skin infections in the Greater Los Angeles area are now MRSA. The latest issue of Skin & Allergy News also had a front page article on this. Los Angeles is about 2 years from Santa Barbara in the transfer of such events. Prior to 1985, vancomycin resistance in human pathogens had not been described in the literature. A decade later, more than one half of the hospitals in New Jersey contained strains of vancomycin insensitive bacteria. By the end of 1998, one quarter of enterococci isolated from intensive care units across the U. S. expressed resistance to vancomycin.

Recent publications in the medical literature discuss the cost of drug resistant bacteria. The annual cost in the U. S. was estimated to be upwards of $ 30 billion annually ( Dominguez EA, et al. Infection Control & Hospital Epidemiology, vol 21,# 1, supp, Jan 2000, p S4).

It was assumed for a long time that gene transfer between different species of microorganisms is a very rare event at best; that view has changed. The available evidence suggests that interspecific transfer of genes has occurred between the three major groups of organisms: archaebacteria, eubacteria and eucaryotes. There is very strong evidence that gene transfer easily occurs between distantly related bacteria. Marcinek, et al [ 10] estimated that under the natural conditions of a sewer treatment works, between 106 to 109 gene transfer events between different E. faecalis strains should take place per day. The maximum number of transfer events for the sex pheromone USEPA, 2003d 63 plasmids between different strains of E. faecalis in the municipal sewage water treatment plant was found to range from 10( 5) to 10( 8) events per 4 hour period. This work also indicated that gene transfer should take place under nat Iversen, et al, [ 11] isolated VRE in 21 of 35 untreated sewage samples ( 60%), from 5 of 14 hospital sewage samples ( 36%), from 6 of 32 treated sewage samples ( 19%), and from 1 of 37 surface water samples. It was speculated that antimicrobial drugs or chemicals released into the sewage system sustained VRE in the system. Others [ 5] have demonstrated direct evidence that related tetracycline resistance encoding plasmids have disseminated between different Aeromonas spp. and E. coli and between the human and aquaculture environments in distinct geographical locations. Collectively, these findings provide evidence to support the hypothesis that the aquaculture and human compartments of the environment behave as a single interactive niche.

Ribeiro [ 12] and others [ 13] have found that as these organisms progress further through sewer treatment, the level of resistance and number transferred plasmids increases. Reinthaler et al [ 14] found that the highest resistance rates were found in E. coli strains of a sewage treatment plant which treats not only municipal sewage but also sewage from a hospital. Thus, these authors concluded that sewage treatment processes contribute to the dissemination of resistant bacteria in the environment.

One of the issues being studied locally is the leaking sewer system that underlies most cities. There has been a sufficiency of studies to raise questions about exfiltrationøthe loss of sewer effluent from these sewer mains. That rising ground water actually enters into many of these older systems is now well beyond question. The issue is one of logic. If rising ground water gets in through failing joints and cracks, what keeps sewer water from utilizing these same portals when the surrounding ground water falls below them?

Cenci, et al [ 15] reviewed the incidence and the patterns of the antibiotic and metal resistance in 106 strains of Escherichia coli isolated from ground waters, used also as drinking water supply. These organisms were studied in comparison with the resistance behavior in the 104 strains of the same microorganism isolated from non hospitalized patients. When, however, these were compared to hospitalized patients, the patterns of the antibiotic multiresistances and the strains isolated from patients and from ground waters did not differ greatly. The authors concluded that their findings strengthened the hypothesis that resistance to antibiotics had been acquired by Escherichia coli strains before reaching the ground waters.

If the above has any validity, then what of the possible effects of different pharmaceutical groups such as anti tumour drugs, antibiotics and contrast media as well as absorbable organically bound halogens AOX resulting from hospitals effluent input into sewage? Recently, the occurrence and fate of pharmaceutically active compounds ( PhACs) in the aquatic environment was recognized as one of the emerging issues in environmental chemistry and as a matter of public concern [ 16]. Residues of PhACs have been found as contaminants in sewage, surface, and ground and drinking water samples. Again this begs the issue of leaking sewer mains and a need for pretreatment. USEPA, 2003d 64 Most antibiotics and their metabolites are excreted by humans after administration and therefore reach the municipal sewage with the excretions. Kummerer, et al [ 17] looked at a worst case scenario on found concentrations of the antibiotics in hospital effluents. These concentrations were estimated and compared with minimum inhibitory concentrations for susceptible pathogenic bacteria and with the genotoxic potency. Both the concentrations calculated for hospital effluents and the adverse effects in bacteria were in the same order of magnitude.

AOX are mostly persistent in the environment, and accumulate in the food web. One important source of AOX in hospital effluents may be x ray contrast media containing an iodine carbon bond. These materials may also add to selection pressures and development of resistant strains.

Others [ 18] have noted that the mere process of chlorinating effluent tends not only to increase resistance, but also increase the competitive edge of these survivors. Thus, we are now seeing developing resistance to chlorine, other antiseptics, and disinfectants. This raises some interesting academic as well as practical questions at the cellular and molecular level. For example would developing resistance to chlorine also affect the efficacy of hypochlorite released within lysosomes, there by reducing effectiveness of leukocytes?

The workers at sewer plants are also at risk. Several papers [ 19,20,21] have reported on transfer of viral particles and bacteria in aerosols that are generated by and surround many of these plants. In addition, there are studies on wind drift of these plumes into the surrounding neighborhoods.

Response These comments , for the most part, do not address that portion of the April 9, 2003 Federal Register notice that requested comments on the pathogen portion of EPA's Draft Action Plan. One comment, the issue of resistant pathogens originating from hospital patients with a potential to be found in sewage sludge, are responded to by referring to Project 11 in Section VII B of today's notice on publishing the proceedings of the USEPA USDA Workshop on Emerging Infectious Disease Agents and Issues Associated with Animal Manures, Biosolids, and Other Similar By Products. Among the information from the Workshop that will be published will be information on the potential for the occurrence of antibiotic resistant pathogens in sewage sludge and animal manures.

EPA Log # 8: David A. Burrows Comment The Pennsylvania studies ( Federal Register p. 17386) should be peer reviewed studies of at least one year duration and with as broad a scope as possible. A thirty day sampling period is insufficient to study the possible regeneration of pathogens that could occur during a normal year of agricultural use of biosolids. There is also a need for sampling during all weather conditions normal for the test area.

A molecular pathogen tracking exposure study as a follow up to the PA/ USDA/ EPA study would be beneficial. ( Federal Register p. 17386) USEPA, 2003d 65 Response First paragraph of these comments: See the EPA response to EPA Log # 40 regarding the Pennsylvania field studies in the Exposure Section of this document. The study design will be peer reviewed to consider these comments.

Second paragraph: EPA now views the molecular pathogen tracking exposure study as lower priority and will not be in the research plan for projects to be initiated or completed within 2 3 years. The execution of well designed field exposure studies as described in the Exposure Section of this document should provide the necessary information that the molecular pathogen tracking study would have provided.

EPA Log # 21: Lynton S. Land Comment In several previous letters ( 12 / 01 / 01,02 / 28 / 02,061 / 06 / 02) I have asked that EPA seriously consider the role of gulls in transporting human pathogens to waterways impaired because of fecal coliform bacteria. There can be no doubt that gulls foraging in fields to which Class B sewage sludge has been land applied will be contaminated with human pathogens, considering that the average sludge truck contains trillions of CFU ( Colony Forming Units). The Virginia Department of Environmental Quality has recently concluded that Virginia waterways that are impaired ( and restricted for the harvesting of oysters) because of high human fecal coliform bacteria, not bacteria from wildlife, based on BST ( Bacterial Source Tracking) studies. There is no excuse whatsoever to permit the land application of Class B sewage on fields within the foraging range of gulls near waterways impaired because of high human fecal coliform levels. Attached is some previous correspondence with the Virginia Department of Health, previously sent to EPA, which outlines my concern. I request that this issue be formally addressed by EPA in your response to NRC's criticism of existing sewage sludge regulations.

Response Project 4 " Field Studies of Application of Treated Sewage Sludge" of today's FR notice could develop information of this type.

EPA Log # 8: David A. Burrows Comment There is a need for the use of indicator organisms such as Clostidium perfringens as recommended by the NRC. ( Federal Register p. 17388)

Response EPA thanks the commenter for his suggestion which will be brought to the attention of EPA's Pathogen Equivalency Committee ( Please see also Project 9 in Section VII B of today's Federal Register Notice " Support Pathogen Equivalency Committee"). The PEC can evaluate and recommend the use of indicator organisms other than the current indicator organism, fecal coliforms, specified in the current Part 503 Standards.

EPA Log # 12: Edward H. Bryan Comment This is in response to your request for comments on sewage sludge disposal regulations relating to sludge applied to land and is with reference to the report " Biosolids USEPA, 2003d 66 Applied to Land " by the NRC Committee EPA commissioned to assist in reviewing these regulations. On Page 44 of this report, Alternative 5e is titled " Beta Ray Irradiation Process," and described as irradiation of sludge with " beta rays from an accelerator." Beta rays are not emitted from an accelerator nor is it technically correct to call the process of irradiating materials by use of a beam of energized electrons from an accelerator a " Beta Ray Irradiation Process." The NRC Committee may not have noted these technical errors in the regulations or, if noted, did not consider them to be within the scope of its advisory function in the process that led to its report. However, it seems appropriate that EPA would consider correcting these errors and others like them if there are more when its sludge regulations are revised. Alternative 5e should be labeled Electron Beam Irradiation Process and the phrase " beta rays from an accelerator " should be replaced by " electrons from an electron accelerator."

Response EPA thank you for your comment which will be evaluated as soon as possible. A correction to Part 503 Standards will be issued if deemed necessary.

EPA Log # 29: Henry J. Staudinger Comment E. EPA's Pathogen Strategy is Not Adequate. NRC Recommends that EPA review approaches for developing microbial analytical methods and conduct microbial risk assessments to analyze sensitivity and to ascertain critical information needed to reduce uncertainty of those exposed to biosolids.

EPA's willingness to consider studies to better understand the potential adverse health consequences of pathogens is a start. However, even if EPA decides to fund independent studies, the lack of input data discussed earlier severely limits the viability of the strategy.

The EPA/ USDA/ DEP project referred to is not designed to address the issues raised by NRC. Moreover, as discussed earlier, that project addresses only selected pathogens and has not been designed to test biosolids most likely to contain pathogens present when health complaints have been made. Industry generated studies provide little comfort that objective pathogen information will become available.

Response See the EPA response to Comment Log No. 51 in the Methods Development section . Please see the EPA response to EPA Log No. 40 concerning the Pennsylvania Study in the Exposure Section of this document. In addition, please see Project 11: Publish the Proceedings of USEPA USDA Workshop on Emerging Infectious Disease Agents and Issues Associated with Animal Manures, Biosolids, and Other Similar By Products in Section VII B of today's Federal Register Notice.

EPA will make available recent information on pathogens in sewage sludge and animal wastes by publishing the proceedings of the June 2001 USEPA USDA workshop. The July 2002 NRC Report called for more information on the risks of disease associated with pathogens and how to analyze for them. It also called for more information on the reliability of sewage sludge USEPA, 2003d 67 disinfection processes. The workshop proceedings document will partially answer the questions the NRC raised.

In June 2001, EPA and USDA sponsored a workshop on" Emerging Pathogen Issues in Biosolids, Animal Manures, and Other Similar By Products" ( USEPA, in press). The workshop brought together experts in sewage sludge management and animal wastes to review the state of the science, exchange ideas on how to deal with unresolved issues and suggest areas where the scientific community should focus its efforts. Participants discussed: ° viruses, bacteria, protozoa, prions, fungi, and helminth ova; ° migration of pathogens to groundwater and air from recycling and treatment operations; ° qualitative identification and detection methods for pathogens; the fate of antibiotics in animal and human wastes; ° pathogen resistance to antibiotics; and ° susceptibility of people with immuno suppressed conditions to pathogens. As stated in Category E ( Pathogens) of the preliminary strategy dated April 9, 2003 ( 68 FR 17389), EPA will make available the information produced at this workshop on pathogens in sewage sludge and animal wastes by publishing the proceedings of the workshop. The proceedings from the workshop have been peer reviewed by national and international experts, and the report will be published in early 2004.

In the future, EPA intends to use the information that was produced by this Workshop to evaluate the pathogen portion of the Part 503 Standards and, if warranted, propose amendments to these standards for public comment.

EPA Log # 37: David A. Burrows Comment On page 17384 of the Federal Register, in goal # 3 of " Major Long Term Goals..." the word possibly should be deleted so that the statement reads " To strengthen its biosolids program, EPA will include quantitative microbial assessment, improved understanding of exposure pathways/ scenarios, and molecular tracking."

EPA has apparently not developed a clear plan to determine the effectiveness of site restrictions in relation to Class B sewage sludge. The NRC recommended ( page 305 NRC report): " Studies should be conducted to determine whether the site restrictions specified for Class B biosolids in the Part 503 rule actually achieve their intended effect with regard to pathogen levels." The NRC also recommended: " Site restrictions, bufferzones, and holding periods for land applied Class B biosolids should consider geographic and site specific conditions that affect pathogen fate and transport" ( page 304 NRC report).

Response See the response to Comment log No. 29 in this section. As stated in this response, amendments to the pathogen section of the Part 503 standards including site restrictions for Class B sewage sludge are possible after EPA evaluates information from the Workshop described in Project 11 in Section VII B of today's Federal Register Notice. USEPA, 2003d 68 EPA Log # 40: Thomas F. Albert Comment Comment # 1: On page 17384 in item 3 of " Major Longer Term Goals " the word " possibly" should be deleted. To strengthen its biosolids program EPA SHOULD include ( not possibly include); quantitative microbial risk assessment, improved understanding of exposure pathways/ scenarios, and molecular tracking.

Comment # 23: On page 17388 in the section " How EPA Plans to Address NRC Pathogen Recommendations" is noted that " EPA currently uses a technology and management practices based approach to minimize pathogen exposure." This is MISLEADING. The current EPA approach reduces pathogen exposure but there is no evidence that it minimizes pathogen exposure. If EPA has proof that these practices do truly minimize ( rather than just reduce) pathogen exposure, then EPA should present proof. In the interests of protecting human health, why doesn't EPA now take a risk based approach to assessing pathogens in sewage sludge ( as noted on page 263 of NRC report)? In 1993 when standards were set for the Part 503 rule, it may not have been e practical to set risk based pathogen standards. It is now possible to set risk based pathogen standards, why doesn't EPA propose this in its response to the NRC report?

Comment # 24: On page 17388 in the section " How EPA Plans to Address NRC Pathogen Recommendations" is another mention of EPA " Considering" an action? EPA " is considering studies to better understand the measurement, control, and fate of pathogens during the production and land application of sewage sludge." Why on earth hasn't EPA already done this? In the interest of human health such studies should have already been done. If they have not been done they should be a high priority for doing. " Considering" is the wrong word, EPA should DO these studies NOW.

Comment # 25: On page 17389 in the " Research" section EPA is again " considering" an action. EPA " is considering research in at least three general areas: ( 1) Development of improved pathogen analytical techniques; ( 2) assessment of exposure and risk for critical pathways and pollutants, and ( 3) evaluation of sewage sludge processing and land application methods and site restrictions." EPA then follows with a masterpiece of understatement, " Results of such research will assist the Agency in determining where improvements may be needed" ( Note that improvements MAY be needed!) Why is EPA only CONSIDERING research in these 3 areas? These areas are all included in NRC recommendations. EPA should be DOING these studies not just " considering" such studies. What possible excuse can EPA offer for not doing such studies?

Comment # 26: On page 17389 ( research section) is there again a brief mention of the cooperative EPA/ USDA/ PA DEP sludge study in Pennsylvania?

Comment # 27: On page 17389 ( research section ) mention is made of sludge pathogen studies at the University of Arizona. Have these studies been peer reviewed at the design stage? Will they be peer reviewed at the draft final report stage? USEPA, 2003d 69 Comment # 28: On page 17389 ( research section) it is good to see mention of " phosphorus overload'' as a concern in relation to sewage sludge applied to land. EPA should clearly admit that current use of sewage sludge on farm land overloads the land with phosphorus ( exceeds need by the plants) and thereby contributes to phosphorus runoff and subsequent pollution of groundwater and streams. If on the other hand, EPA has proof that this is not the case, it should be mentioned.

Comment # 29: At the top of page 17390. the last 7 lines of the " research section'' contain one of the rare mentions of pathogen risk assessment, but again it is " weasel worded" when we see that EPA considers this a potential future activity and is only " considering" other relevant work. The EPA statement reads, " Potential future pathogens activities will include analytical methods development, exposure and risk assessment. The Agency is also considering continuing site specific evaluations of current treatment and land application processes,   " Why are the pathogens studies " potential" and " future"? Why aren't they being done NOW? Why is EPA " considering" continuing site specific evaluations? Why isn't EPA certain that it will continue site specific evaluations?

Response Please see the EPA responses to comment Log No. 51 in the Methods Development section and comment Log No. 29 in this section of the document. Also see the response to comments Log No. 40 on the Pennsylvania study in the Exposure Section of this document. As responded to this commenter in the Survey section of this document, EPA believes that it has removed ambiguity from its research action plan as described in Section VII B of today's Federal Register notice.

EPA Log # 25: Northumberland Association for Progressive Stewardship ( NAPS) Sewage Sludge Study Group Comment E. Pathogens Lines 898 939. We strongly suggest that EPA list the members and contributors to the Water Environment Research Foundation ( WERF), as well as other " independent" research organizations and make this information public, as you have with other organizations in your paper. Furthermore, we recommend that the degree to which such organizations rely on support from sludge land application companies be taken into consideration when evaluating their data and recommendations. This also applies to colleges and universities.

Response Please see EPA's responses to Log No. 8 in the Risk Assessment section and to your previous comment in the Survey section of this document that raised the issue of data integrity from sources associated with the wastewater industry. EPA will consider for use, all data and information that meets the standards of EPA's Data Quality Guidelines.

Environmental Groups EPA Log # 43: Natural Resources Defense Council ( NRDC) USEPA, 2003d 70 Comment PATHOGENS NRC's Report makes a number of important recommendations for improving the technology based approach used by EPA to address risks posed by pathogens in sewage. Those recommendations include conducting an updated national survey of pathogens in raw and treated sludges, analyzing hazard information reflective of newly available information using geographical and site specific factors in setting use restrictions; considering use of additional indicator organisms; verifying the efficacy of current site restrictions; and using quantitative microbial risk assessment (" QMRA ") to improve current ` regulatory criteria (" PEC").

EPA's Response to these specific recommendations is both vague and incomplete. Reference is made to " an ongoing biosolids research program focused on selected pathogens," but EPA fails to elaborate on the scope of this research program or what particular studies fall within its purview. Three possible research priorities are listed: "( 1) development of improved pathogen analytic techniques; ( 2) assessment of exposure and risk for critical pathways and pollutants; and ( 3) evaluation of sewage sludge processing and land application methods and site restrictions." NRDC agrees that these general areas of research are important and could potentially lead to the implementation of some of the structural changes to pathogen regulations recommended by NRC. However, the lack of detail, specificity, and commitment in EPA's Response is extremely concerning. Pursuant to NRC ' s recommendations, EPA needs to design a systematic approach to incorporating these potential research priorities into a long term plan for modernizing the pathogen regulations. In addition, while additional research on pathogens in sludge could be helpful, it needs to be done by independent scientific bodies that are not funded by the sludge industry through membership dues, grants, or other sources of funding.

EPA's discussion of the University of Arizona study exemplifies the general deficiencies in EPA's limited approach. The research parameters and goals of this single study appear promising. Nonetheless, this study, albeit at several sites around the country, is incapable of producing the type of data and information necessary for a comprehensive evaluation and overhaul of existing pathogen regulatory criteria. Without complementary studies across the country that are planned and coordinated with broader goals if mind, such data and information will remain out of EPA's reach.

Response With respect to developing analytical protocols for microbials, see Project 3 " Methods Development, Optimization, or Validation for Microbial Pollutants in Sewage Sludge" in Section VII B of today's Federal Register Notice. With respect to including microbials in an analytical survey, EPA has committed to do that if adequate microbial analytical protocols are available ( see Project No. 5 " Targeted National Survey of Pollutants in Sewage Sludge" in Section VII B of today's Federal Register Notice as described in the Survey Section of this document. With respect to QMRA development, in Section VII B in today's Federal Register Notice, see Project 8: " Assess the Quality and Utility of Data, Tools and Methodologies to Conduct Microbial Risk Assessments on Pathogens."

To better inform research activities in sewage sludge and microbial risk assessment, EPA will inventory and assess data, methods, and tools for risk assessment on pathogens in sewage USEPA, 2003d 71 sludge. The NRC report indicated that additional scientific work is needed to reduce persistent uncertainty about the potential for adverse human health effects from exposure to biosolids. The document goes on to recommend that EPA use improved risk assessment methods. EPA currently regulates the processing, use, and disposal of sewage sludge through CWA regulations in Part 503, that impose numeric standards and management practices for sewage sludge applied to land. For the most part, the numeric standard for chemical pollutants in existing regulations are risk based, while the microbial management practice standards are technology based. In issuing Part 503 in 1993, the Agency acknowledged that it lacked essential tools and data to conduct microbial risk assessments on sewage sludge. This project will address those microbial risks posed by exposure to sewage sludge, it will serve as a vehicle to better define the deficiencies in microbial risk assessment, and better identify research needs for sewage sludge risk assessment.

This project will start with a problem formulation step to identify the key elements in assessing pathogen risks in land applied sewage sludge. During the second phase, EPA will develop a plan to identify the available and appropriate methods and data to perform the risk assessment defined in problem formulation. An expert panel will review the material and EPA will address panel comments in the final document.

EPA will develop a scenario that includes issues involved in the risk assessment: sources of organisms, potential receptors, routes of exposure, and environmental and management conditions affecting exposure. The scenario will also identify pathogens based on studies of the composition of sewage sludge, incidence of contamination reported in the literature, and numbers of organisms recovered from sewage sludge. The Agency will develop rates and methods of application protective of at risk populations ( such as those with occupational exposures or those living near application sites). The study will also consider sensitive populations such as children, the elderly, or those persons with immune system problems. We will develop a conceptual model to characterize different routes of exposure to microbes under realistic scenarios. The workgroup will lay the foundation for defining the conditions and criteria for microbial risk assessments of sewage sludge.

The workgroup will also review the scientific literature to identify available tools, methods and data, as well as gaps, for conducting an assessment under the defined conditions. An expert panel will critique the findings and recommend future research for microbial risk assessment of sewage sludge. The final product in FY 2005 will be a peer reviewed plan for future analysis.

With respect to an ongoing EPA pathogen research program, EPA is committed to reviewing the published results of the USEPA USDA Workshop referenced in response to Comment Log No. 29 in this section of this document. Finally with response to the criticism of the University of Arizona study, the project leader has performed these type of studies in several locations in the United States under various meteorological conditions. The results of these studies have just been published and EPA will be reviewing these ( Rusin et al, 2003).

Municipal Wastewater Treatment Plants USEPA, 2003d 72 EPA Log # 14: Metro Wastewater Reclamation District Comment The Metro District endorses the NRC report's recommendation to study the correlation between pathogen destruction and indicator organism levels in biosolids from various treatment processes, such as anaerobic digestion, aerobic digestion, and lime stabilization. Studies of this type will provide data that either provide substantiation for the protective nature of the Class A and Class B pathogen destruction requirements, or show there is a need to revise the Class A or Class B pathogen destruction criteria.

Response Project No. 4 " Field Studies of Application of Treated Sewage Sludge" in Section VII B can be expanded in the future to study the correlation between pathogen destruction/ reduction processes and the presence/ quantification of indicator organisms in the treated sewage sludge.

Unknown EPA Log # 34: Anonymous Comment A second issue is the lack of critical specific detail on many of the EPA responses. Many of the responses fail to define clear timelines on achieving any type of results. The NRC recommended " the Agency review approaches for developing microbial analytical methods and conducting risk assessments ( Quantitative Microbial Risk Assessments)". The EPA's response was " is considering studies". The open ended nature of this type of response is not acceptable. The response should be direct and clear.

The third major issue with the draft response is the significant failure to address many of the recommendations. The number of specific cases are too numerous to include in this summary however some specific examples include : ( 1) " The PEC should be funded , supported, and officially sanctioned as an integral part of the federal biosolids program" ( NRC report p. 96) and ( 2) " Provisions for allowing distribution of Class A biosolids in bags or other containers should not be allowed when they do not meet the pollutant concentration limits" ( NRC report p. 97).

Response In response to public comments on the draft April 2003 FR Notice, EPA attempted in this final response to provide clear timelines and more details on specific activities or research, and to better describe how those activities address NRC recommendations, areas of uncertainty identified in the NRC report, and areas the Agency believes will improve the sewage sludge program. For support to the PEC, please see Project 9 " Support Pathogen Equivalency Committee."

Association EPA Log # 30: Tri TAC Comment Pathogens USEPA, 2003d 73 Tri TAC generally supports EPA's planned pathogen research areas, development of improved pathogen analytical techniques, assessment of exposure and risk for critical pathways, and evaluation of biosolids processing and land application methods and site restrictions.

The NRC Report recommended that the EPA consider funding, supporting, and officially sanctioning the Pathogen Equivalency Committee ( PEC) as part of the federal biosolids program. While Tri TAC does not object to this recommendation, we do suggest that if EPA decides to officially recognize the committee, that it open membership on the PEC to include qualified scientists employed by wastewater treatment plants and private biosolids contractors. As currently structured, the PEC includes only employees from EPA and the CDC. Because of this limitation, the PEC has not benefited from the expertise that scientists from the regulated community could contribute, especially related to current application methods, site restrictions, and other local variables.

Tri TAC supports EPA's plans to continue funding relevant scientific research concerning the impact of biosolids on human health and the environment. As part of this effort, Tri TAC recommends that EPA consider funding studies conducted by wastewater treatment agencies or private biosolids applicators. These entities may be able to develop data useful to EPA's long term goals of understanding the benefits and potential consequences of biosolids land application and determining whether existing Part 503 site management restrictions are effective. In addition, both wastewater treatment agencies and private biosolids management companies may already have data from in house studies that could be useful for EPA's activities. Tri TAC encourages EPA to tap into this resource.

Response EPA appreciates these comments. As described in Project No. 9 in Section VII B of today's Federal Register Notice, EPA will devote sufficient resources to the Pathogen Equivalency Committee. Finally, EPA intends to reach out to stakeholders including wastewater treatment agencies to obtain needed data external to the Agency.

EPA Log # 50: Water Environment Federation ( WEF)

Comment Focus on Priorities   The document reflects a strong emphasis on pathogens and odors, which are areas of primary concern to the public. WEF agrees that EPA should support further study on pathogen issues in biosolids, animal manures and other similar by products. EPA should also support additional research on odor associated with biosolids processing, utilization, and management of biosolids at the treatment plant to minimize odors during subsequent processing or land application. Some promising early research has been accomplished in these areas and needs to be continued so as not to lose momentum and progress made to date.

E. Pathogens In the strategy, EPA indicated that the Agency is considering studies to better understand measurement, control, and fate of pathogens during the production and land application of biosolids. The strategy also describes several programs focused on developing a better understanding of pathogens. WEF supports ongoing research programs focused on pathogen USEPA, 2003d 74 issues and EPA's continued use of the Pathogen Equivalency Committee. WEF also encourages EPA to continue collaborating with USDA, which is grappling with similar pathogen concerns in land applied manures, and to review and evaluate relative WERF programs.

Response EPA agrees with these comments.

EPA Log # 46: Association of Metropolitan Sewerage Agencies ( AMSA)

Comment Pathogens AMSA generally supports EPA's planned pathogen research areas: development of improved pathogen analytical techniques, assessment of exposure and risk for critical pathways, and evaluation of biosolids processing and land application methods and site restrictions.

The NRC Report recommended that the EPA consider funding, supporting, and officially sanctioning the Pathogen Equivalency Committee ( PEC) as part of the federal biosolids program. While AMSA does not object to this recommendation, we do suggest that if EPA decides to officially recognize the committee, that it open membership on the PEC to include qualified scientists employed by wastewater treatment plants and private biosolids contractors. As currently structured, the PEC includes only employees from EPA and the CDC. Because of this limitation, the PEC has not benefited from the expertise that scientists from the regulated community could contribute, especially related to current application methods, site restrictions, and other local variables.

AMSA supports EPA's plans to continue funding relevant scientific research concerning the impact of biosolids on human health and the environment. As part of this effort, the Association recommends that EPA consider funding studies conducted by wastewater treatment agencies or private biosolids applicators. These entities may be able to develop data useful to EPA's long term goals of understanding the benefits and potential consequences of biosolids land application and determining whether existing Part 503 site management restrictions are effective. In addition, both wastewater treatment agencies and private biosolids management companies may already have data from in house studies that could be useful for EPA's activities. AMSA encourages the Agency to tap into this resource.

Response EPA agrees with these comments. Please see the response to Comment Log Nos. 30 and 50 in this section of this document.

Counties EPA Log # 28: Solano County Department of Environmental Management Comment 3. Pathogens: their existence and management Solano County DEM is not only interested in the range of pathogens found in biosolids, but the mortality of the pathogens as a result of different treatment and land application processes. The USEPA response appears to address this issue as part of its three item approach. Of interest to USEPA, 2003d 75 Solano County DEM in regards to the land application of Class B biosolids is a comparison study on mortality rates of pathogens between actual sites where incorporation of biosolids is done versus those sites where only surface application of biosolids is used. Such a project should include a study on the impacts, if any, these two different application methods have on long term potential exposure of animals and people to pathogens or other contaminants.

Response Project No 4 Field Studies of Application of Treated Sewage Sludge in Section VII B of today's Federal Register Notice responds to these comments.

States EPA Log # 52: Washington State Department of Ecology CommentPathogen Equivalency Committee. In its response EPA notes that it has an ongoing biosolids research program focus on selected pathogens, and is expanding the program during this fiscal year. EPA says in regard to the Pathogen Equivalency Committee, " The Agency formed and has supported the PEC since 1985."

I am glad to hear that EPA is able to expand its research program for pathogens in biosolids. With regard to support for the PEC, however, I am disappointed to see EPA make the above statement because it again illustrates a significant disconnect. Allowing the PEC to exist is not the same as supporting it. My concept of support must be markedly different, but I don't believe I know a single person ( and after 15 years in this area of work I know a few) who would argue that the PEC has been adequately supported ( except possibly the author of the EPA response here). A report contracted by EPA and prepared by Dr. Charles Haas at Drexel University, and actually cited in the NRC report documents shortcomings and needs. The very first short term recommendation begins by saying, " At present the bulk of the clerical and secretarial functions of the PEC ( e. g., correspondence with petitioners, arrangements for meetings, maintenance of files) is personally performed by the chairman of the committee." This is an appalling use of a valuable resource. I believe EPA could say that the PEC is supported if it would implement the rather modest recommendations in Dr. Haas' report.

Response Project No. 9 Support Pathogen Equivalency Committee in Section VII B of today's notice responds to these comments.

EPA Log # 53: Michigan Department of Environmental Quality CommentSection VIII. E. Pathogens  Pathogen Activities  EPA's Pathogen Equivalency Committee ( PEC) It is stated that the Agency " formed and has supported the PEC since 1985". This statement does not reflect what has actually been happening. It is my impression that the PEC has struggled to perform its job as long as it has existed with virtually no support and funding. The NAS committee found that the PEC was inadequately supported and recommended on pages 96 97 that they be funded, supported, and officially sanctioned as an integral part of the federal biosolids USEPA, 2003d 76 program. The Agency must either commit to all of the recommendations in the NAS report and those provided by an independent assessment report done by Chuck Haas ( 2001) and cited in the NAS report, or make a policy decision not to allow new technology for biosolids treatment.

Response Please see the response to EPA Log No. 52.

EPA Log # 48 and 39 ( duplicates): Wisconsin Department of Natural Resources Comment12. Section VIII. E. Pathogens  Research  It is stated that EPA has an ongoing and expanded biosolids research program focused on specific pathogens. More specific detail should be provided on this program and its specific projects. It is also stated that EPA is " considering" research in at least three general areas. Much more specific detail is needed for what is under consideration and what will actually be done.

13. Section VIII. E. Pathogens  Pathogen Activities  It is stated that EPA and Duke University published a paper examining potential health effects from odor emissions. This paper has been largely misunderstood and inappropriately used since its publication. Is EPA purporting that this paper actually published results demonstrating health effects from biosolids odors at land application sites? No causal relationship conclusions between biosolids odor and health effects were drawn from that paper by this reader. The reason for citing this paper in this response should be clarified. At the same time the study underway by the University of Arizona Water Quality Center is very critical and will provide much needed data. This work should be continued to be supported.

14. Section VIII. E. Pathogens  Pathogen Activities  EPA's Pathogen Equivalency Committee ( PEC)  It is stated that the Agency " formed and has supported the PEC since 1985". In fact the NAS committee found that the PEC was inadequately supported and recommended on pages 96 97 that they be funded, supported, and officially sanctioned as an integral part of the federal biosolids program. This included the need to have a formal portion of their time dedicated to PEC responsibilities and adequate funding provided. The Agency must either commit to all of the recommendations in the NAS report and those provided by an independent assessment report done by Chuck Haas ( 2001) and cited in the NAS report, or make a policy decision not to allow new technology for biosolids treatment. We would vehemently object to the latter option, but the PEC will soon become unworkable unless a dedicated commitment is made to support it.

15. Section VIII. E. Pathogens  Pathogen Activities  A WERF study evaluating phosphorus availability in biosolids is an important study. However, it is hoped that site conditions and management practices are examined as well as phosphorus availability in assessing potential impacts to surface and groundwater. This should be further explained. It is also unclear why a phosphorus study was listed under " Pathogen Activities".

16. Section VIII. E. Pathogens  Planned Pathogen Activities  It is stated that EPA is " considering" studies to assess treatment efficacy and natural attenuation in soil after application. Both of these may be part of the Exposure Study referenced above in comment 8 and in Part B of USEPA, 2003d 77 the response, but that is not clear. Both studies are critical and should be conducted. As recommended on page 97 of the NAS report, standard design criteria should be adopted nationally and these studies are mandatory to establish that criteria.

Response Please see in Section VII B of today's FR notice Project No. 3 ( Methods Development, Optimization, and Validation for Microbial Pollutants in Sewage Sludge) and Project No. 8 ( Assess the Quality and Utility of Data, Tools and Methodologies to Conduct Microbial Risk Assessments on Pathogens) for a description of specific research projects focused on pathogens.

EPA is aware of the Duke University publication on the human health impacts of odors. EPA has not developed a position as of yet on the findings of this report. EPA is also aware of the research being conducted at the University of Arizona and will be tracking this and other studies of this type.

Project No. 9 Support Pathogen Equivalency Committee in Section VII B is responsive to the comments contained in the third paragraph. Finally in response to the last paragraph of these comments, Project 4 in Section VII B ( Field Studies of Application of Treated Sewage Sludge) address these comments.

EPA Log # ?? 59 ( EDKT # 101): New Jersey Department of Environmental Protection Comment There was no mention of the work being performed by the Interagency Steering Committee on Radiation Standards ( ISCORS). Both ISCORS and this Department have gathered extensive information with regards to naturally occurring radionuclides in biosolids. The EPA should consider this information in fulfilling its obligation in responding to and implementing the recommendations in the NRC report.

Response As stated on page 28 of the NRC report "... radioactive contaminants were not included in the committee's assessment, even though the committee is aware that radioactive compounds may be present in biosolids." That issue and resulting studies is under the aegis of ISCORS. Results on this activity were published in the Federal Register as an interagency Federal Government product on November 26, 2003 at 68 Federal Register 66503 66504.

TOPIC F. HUMAN HEALTH STUDIES Summary Response EPA received a large volume of comments on this topic. EPA takes seriously the allegations of human health impacts. EPA's commitment to address this issue is described by Project 6 in Section VII B of today's notice Participate in an Incident Tracking Workshop and Project 7 Conduct Exposure Measurement Workshop. A description of these two projects as it appeared in today's FR notice is given below since they answer many of the comments received on this topic.

Project 6: Participate in an Incident Tracking Workshop USEPA, 2003d 78 One of the highest research priorities identified by the NRC and participants at the July 2003 WERF Biosolids Research Summit is the need for rapid response investigations of reported health effects potentially resulting from land application practices. EPA also received many public comments urging development of an incident tracking and response process. The Agency agrees that developing an incident tracking program is important. However, the Agency believes that it should not develop an incident monitoring program on its own, but should include various stakeholders who have had experiences with incidents related to sewage sludge, stakeholders who may be interested in participating, and those who have the expertise and should take part in helping to develop such a program. As stated above, stakeholders who have had experiences with reported incidents related to land application of sewage sludge should be consulted. A program of incident monitoring and investigation could be modeled after an existing program. Once such organization that has experience with such incidents is the State of North Carolina ( NC). The North Carolina Department of Environment and Natural Resources is responsible for environmental programs in the state, including biosolids and residuals management. One purpose of the program is to assure timely and meaningful response to perceived and actual environmental incidents. The experiences of NC and others could be helpful in developing such a program and determining the next steps.

In order to respond to reported incidents of human illnesses and adverse health effects alleged to have been caused by land application of sewage sludge, and to determine the appropriate next steps in the process, EPA believes that local and State health agencies, in addition to other Federal health agencies, such as the Center for Disease Control and Prevention ( CDC), are positioned best and have the necessary expertise to respond to allegations of adverse health effects following use or disposal of sewage sludge. However, EPA is committed to participating in activities related to this issue and plans to participate in the incident tracking workshop with WERF and other stakeholders in developing the research concepts and methods, and in interpreting and summarizing results.

The first step in the process will take place when WERF assembles stakeholders in a workshop to be held in 2004. EPA will participate in the workshop, which will begin evaluating the next steps for investigating adverse human health allegations following land application of sewage sludge. Ultimately, the objective is to determine whether such reported symptoms of illness can be attributed to the land application of sewage sludge. The Cornell Waste Management Institute ( CWMI) has collected over 300 incidents over the past several years in which residents living near sites where sewage sludge has been applied have reported illness ( Cornell Waste Management Institute, 2003; Harrison and Oakes, 2002). However, the CWMI states that it has not been confirmed by scientific investigation that illnesses have resulted from land application of sewage sludge. The information provided by the CWMI may be useful as stakeholders begin to plan for a workshop to address such incidents.

This process, starting with the multi stakeholder workshop, will take place at least through FY 2005. Additional activities beyond that time frame will depend on the outcome of the workshop, work with local, State and Federal agencies, as well as other stakeholders and USEPA, 2003d 79 availability of resources. Additional activities may include participating in subsequent stakeholder meetings or workshops and deciding on additional activities and next steps.

Project 7: Conduct Exposure Measurement Workshop The purpose of this workshop is to identify exposure related research priorities. This workshop is meant to compliment the objectives of the WERF workshop ( see Project 6) or be a related follow up activity that is structured around issues and ideas identified in the WERF workshop. Workshop discussions will focus on exposure measurement tools that researchers or health agencies can use to investigate reports of adverse human health effects from land application of sewage sludge. The discussions and tools will focus on scientific uncertainties related to: ( 1) which particular sewage sludge contaminants or combinations of contaminants may be potentially responsible for disease outbreaks; ( 2) how affected individuals are exposed to these contaminants; ( 3) how sewage sludge treatment and management practices can reduce potential risks, and ( 4) how good analytical methods and monitoring have to be to obtain satisfactory answers. The workshop will explore such topic areas for identifying research priorities as methods development, ambient measurements ( including spatial and temporal monitoring requirements), fate and transport modeling, and exposure measurements, including identifying the specific exposure routes ( e. g., oral and inhalation), exposure pathways ( e. g., eating food, drinking water), and contaminants.

Workshop participants would include representatives from EPA; other Federal, State and local agencies; academia; wastewater utilities; environmental groups; industry; and citizen groups. Participants would identify and possibly prioritize what, when, and where measurements should be taken, and how they should be taken during rapid response investigations. EPA will develop a report to summarize discussions and identify the exposure research tools needed to investigate reported incidents of exposure. Pending the results from a similar effort being sponsored by WERF and in which EPA will participate ( Project 6), we expect to hold this workshop in 2004.

Note: many of the following comments deal with local allegations of human health impacts from the land application of sewage sludge. EPA cannot respond to these comments on these local situations since for the most part, EPA personnel have not investigated these specific local allegations of human health impacts. However, it is these types of local situations that will be investigated using the newly developed protocols for incident reporting.

Academia EPA Log # 51: Ellen Z. Harrison Comment The NRC report reviewed all the available literature pertaining to health studies. The report found that in studies of wastewater treatment plant ( WWTP) and biosolids workers, there are a mix of results., some showing illness response and some not. At the time the NRC report was drafted there was not a single study of the health of neighbors at sites where illness was reported. The NRC committee clearly recognized that a lack of evidence does not represent USEPA, 2003d 80 evidence of a lack of effect. That is why the committee strongly endorsed investigations of the reported incidents of illness.

EPA proposes no health studies and no surveillance of health around land application sites. They propose to " conduct a dialogue with other health based Federal agencies  on the possibility of cooperatively tracking incident reports." ( p 17384).

EPA suggests that they have conducted or are conducting studies on the occurrence of disease ( p. 17389),) but none have been done or are being done to my knowledge ( and I have been very involved with EPA and others in this area so I would expect to know of any such studies) and none are discussed further in the April 9 document. The document refers back to the section on Risk Assessment and Human Health and states that their primary objective is " to characterize pollutants and microbial agents present in biosolids, as well as any associated human health exposure pathways "

This is not the type of human health studies called for by NRC. EPA recognizes that " the NRC sees an immediate need for a systematic approach for investigating claims of disease or illness" ( p. 17390). EPA proposes to " investigate the possibility of developing a process for " notification and tracking. This is not responsive to the NRC recommendation. Keeping track is necessary, but not sufficient. Investigating the possibility of a process is not even committing to keeping track.

In work done at the Cornell Waste Management Institute ( CWMI), research was done to determine what investigation of illness reports was done by EPA and by the states and local agencies ( Harrison and Oakes, 2003). The findings were that no systematic investigations of the health complaints were conducted. The results of our investigation and work published subsequent to the drafting of the NRC report ( Lewis et at, 2002) make it reasonable to believe that in some circumstances neighbors are getting ill from land application of sludges. This makes the investigation of such reports imperative. Since not all land application sites seem to be causing illness, the investigations must be directed to those problem sites. One of the problems with the Pennsylvania study is that it is not addressing such sites. Rather it is an experiment, applying sludges to small areas once and these are not sites at which neighbors have reported symptoms.

The U AZ and the USDA/ EPA/ PA studies are mischaracterized in the April 9 document as evaluating risk ( p. 17390). They are simply monitoring of selected pollutants and bioaerosols. There is a critical need to respond immediately to reported illnesses associated with land application of sludges to determine whether sludge is the probable cause. There is a need to determine what types of sludges and management practices are associated with illness. None of the current or planned research addresses these issues.

Response Please see the Summary Response to this section. NRC recognized the need to investigate allegations of health incidents from exposure to biosolids and EPA has responded by developing two specific projects for tracking health related complaints about biosolids. EPA recognizes the value of the CWMI work on the Investigation of Alleged Health Incidents Associated with Land Application of Biosolids ( Harrison and Oakes, 2002) and the recognition USEPA, 2003d 81 by the commenter that these incidents are not necessarily due to land application of sewage sludge. The information provided by the CWMI will be useful as a first step in tracking reported health incidents and in developing tools that researchers or health agencies can use to investigate reports of adverse human health effects from land application of sewage sludge.

Citizens EPA Log # 8: David A. Burrows Comment The NRC recommended epidemiological studies ( Federal Register p. 17390) would be of broader scope and thus preferable to targeted human health studies.

Response NRC also recognized that complete epidemiological studies are expensive and require extensive data analysis ( top of p. 7 of NRC report). An epidemiological study could help answer many questions regarding cause and effect associated with land applied sewage sludge. However, EPA believes that a more practical and affordable approach to characterize human health impacts and that would yield results in a more timely manner would be from the two projects described in the Summary Response. For that reason, EPA at this time does not support epidemiological studies.

EPA Log # 11: Loudon Neighbors Against Toxic Sludge ( NATS)

Comment EPA must address the serious health problem that threatens rural populations in my state of Virginia and at least twenty other states: the stockpiling and land application of limed Class B municipal sewage sludge near residential areas. This problem has also spread to suburban and urban areas, which apply EQ sludges to parks, school fields, recreational areas, and public gardens.

Overwhelming anecdotal evidence as well as documented evidence in peer reviewed technical and medical journals indicate that people exposed to land applied sludge are getting ill. Even deaths have been linked to this practice. The national press has focused on the issue and victims are finally being heard.

In 1997, the Cornell Waste Management Institute issued a warning that the current rules that govern this practice are not protective of human health, agricultural productivity or the environment.

Response Please see the Summary Response to this section and EPA response to EPA Log No. 51 in this section.

EPA Log # 29: Henry J. Staudinger Comment F. EPA's Human Health Strategy is Not Adequate. USEPA, 2003d 82 NRC Recommends that EPA conduct response incident investigations, targeted exposure surveillance and epidemiological investigations of exposed populations to document the extent to which health complaints can be linked to biosolids exposure.

EPA rejects NRC's recommended epidemiological investigations of exposed populations, claiming that the agency's primary objective is to characterize pollutants and microbial agents present in biosolids, but says it is willing to consider developing a process for timely notification, recording, and tracing incident reports and targeted studies.

As set forth above, EPA's decision not to develop a comprehensive list of pollutants or to reasonably measure maximum exposure rate means that EPA will leave human health protection largely to chance. The USDA/ EPA/ DEP project referred to by EPA confirms the limitations of this strategy.

Until EPA scientifically documents that the health and right to life of sensitive individuals such as the severe immune compromised will not be adversely affected by exposure to biosolids, EPA must prohibit exposure of those individuals to biosolids.

2. EPA's plan to investigate the possibility of developing a process for timely notification, recording, and tracking incident reports in collaboration with other health based Federal agencies.

Timely notification, recording and tracking incident reports are a critical part of any effort to understand the risks associated with biosolids. EPA must develop such a process, not simply " investigate the possibility" of doing so. This information is critical in any effort to identify the causal relationship between biosolids and adverse public health. This should be followed up with a nationwide data base accessible to everyone.

Response See the Summary Response to this section and EPA response to Log No. 8 in this section. NRC recognized that complete epidemiological studies are expensive and require extensive data analysis ( top of p. 7 of NRC report). EPA believes that a more practical and affordable approach to characterize human health impacts and that would yield results in a more timely manner would be from the two projects described in the Summary Response. EPA is committed to developing and implementing such a system called for in the last paragraph of these comments.

EPA Log # 31: David L. Lewis Comment Denunciation of " sludge victims" The NRC report, and our own research as well, calls for epidemiological studies of health related complaints from residents living close to land applications sites. Synagro, on the other hand, simply denounces residents who report adverse health effects. According to the company, all they suffer from is mass hysteria, which can be traced back to the 18th Century when people lived in fear of " unseen evils" and believed in " demons and spirits." If this were not silly enough, Synagro USEPA, 2003d 83 argues that the " so called sludge victims" should bear the burden of supporting any scientific studies on sludge related health complaints.

Processing sewage sludge such that it will remain biologically and chemically stable in the field ( not produce strong odors) increases production costs. Synagro, understandably, has a strong profit motive for arguing that odor cannot cause adverse health effects. Nevertheless, when inadequately treated sewage sludge is spread over large areas, the odor and chemical irritation can be overwhelming. Instead of conducting research to better identify the sources of these problems and improve the practice, Synagro advises EPA to continue with a public relations campaign to convince people that sewage sludge does not smell bad and that people exposed to it experience diarrhea and vomiting because they are uneducated.

In my first expert witness report submitted in Marshall et al v. Synagro et al ( March 29, 2000), I suggested that such adverse effects could be due to mixtures of irritant inorganic and organic chemicals, such as ammonia, trimethyl amines, lime, and bacterial toxins associated with windblown dusts and volatile emissions. The results of our research in this area at the University of Georgia were first presented at a University of Maryland conference ( Lewis, D. L., et al. " Enhanced susceptibility to infection from exposure to gases emitted by sewage sludge: A case study." Biosolids Management in the 21st Century. April 10 11, 2000. College Park, MD). Schiffman et al came to the same conclusions as we did ( J. Agromedicine Vol. 7( 1) 2000). ( See section on Schiffman article near the end of these comments.)

Later, we published a study of residents' complaints ( Lewis, D. L. et al. 2002. Interactions of pathogens and irritant chemicals in land applied sewage sludges ( biosolids) BMC Public Health 2: 11 ( 28 Jun). We found that the most common complaints, such as burning eyes, coughing, respiratory irritation, and difficulty in breathing, are not always associated with odor.

We also found that most residents began complaining about strong odors and adverse health effects before they learned that the source of the odors was sewage sludge. Almost without exception, residents were not notified when sewage sludge was applied, and warning signs were not posted as recommended in the 503 sludge rule.

In other words, initially, these residents had no idea what was causing the odors or the irritation they experienced. Synagro's explanation that they simply exhibited an irrational aversion to fecal material, therefore, cannot possibly explain their complaints.

On the one hand, the industry wants processed sewage sludge to be called biosolids, a term residents would not normally associate with sewage. However, residents exhibit adverse health effects, Synagro attributes them to an irrational aversion to fecal material. In other words, " Keep the public ignorant of what is being spread, and, if they complain, call them ignorant."

Synagro's portrayal of people who endure unbearable stench and ill effects, whether perceived or real, as ignorant and irrational reflects a condescending attitude, even maliciousness. Such an attitude has no place within a professional scientific debate. It does nothing to advance objective USEPA, 2003d 84 investigations that could identify actual problems and give rise to better processing and management practices.

Synagro, as noted earlier, argued that the burden of scientific proof should " fall upon those making allegations of illnesses and deaths, the ` so called sludge victims.'" Residents living near sludged fields, however, already bear the burden of being taxed to pay the EPA to protect public health and the environment. Certainly, the tobacco industry would be less regulated and more profitable if people with heart and lung disease had been left on their own to fund any independent research. The same is true of victims of asbestos, coal dusts, smog and other industry related public health problems.

Consistent with their denunciation of people who report adverse health effects, Synagro describes scientists who suggest a link to adverse health effects as a " vocal minority" of " self interested researchers." How can anyone not laugh when a commercial business argues that scientists who forfeit their jobs and reputations for criticizing the business are serving their self interests? Or, how can a company that has enjoyed the benefits of millions of dollars in taxpayers' money earmarked to promote their industry complain about a few poor scientists for voicing their opinions.

Contradictory conclusions set forth by Synagro include:

° Complaints of adverse health effects should not be tracked. If, however, EPA does track them, it should only consider complaints initiated by a treating physician. Residents who experience " a painful sensation in the eyes or upper respiratory tract" from chemical irritation, however, according to Synagro, do not need to consult a physician because such symptoms are " not severe enough to require medical attention."

° Illnesses among residents exposed to sludge should not be investigated because meaningful epidemiological studies cannot be done on residential communities. Such populations, they argue, are too small and " epidemiologically diverse" to yield any statistically reliable information. On the other hand, Synagro argues that the 1985 Ohio study, which concluded no statistically significant adverse health effects from land application, is a reliable epidemiological study.

Never mind that the Ohio study was largely based on self reported symptoms by residents who completed questionnaires. ( These are known as anecdotal reports in studies linking adverse health effects to sewage sludge.) Also, never mind that many, if not most, of the residents dropped out before the study was completed.

The important thing to remember, industry argues, is that the Ohio study included an unexposed control. Since the sewage sludge was never tested for pathogens, however, the group exposed to sludge may have been unexposed to pathogens as well. It appears that the main thing that makes this study scientifically sound is that the authors concluded that pathogens in the sludge ( the ones that weren't measured and may not have been there) did not infect anyone. USEPA, 2003d 85 Illnesses among workers Synagro dismisses adverse health effects from land applied sewage sludge on the basis that workers who handle sludge are more highly exposed than residents and workers are unaffected. The NRC report cites a number of studies documenting the effects of bacterial toxins and pathogens on workers at wastewater treatment plants. Moreover, many residents living near land application sites are more susceptible to infection and are exposed for longer times than workers.

Furthermore, emission rates of airborne contaminants are proportional to the surface area of sewage sludge exposed to the atmosphere. Sludge spread over hundreds to thousands of acres of land, therefore, will have higher emission rates than sludge confined at waste treatment plants.

It is also important to recognize that, workers, like residents and scientists, are discouraged from reporting illnesses. While few workers are willing to risk losing their jobs by discussing this problem, one exception is a contractor who hauls sewage sludge for the City of Wichita, KS. Before my research at EPA ended, he wrote to me and gave permission to publicly distribute his letter in hopes that it would help EPA understand the plight of workers.

This contractor, who reported his illnesses to NIOSH, complained of recurring E. coli infections and other health related problems among workers hauling sewage sludge and debris separated from the sludge (" grit"). He explains why adverse health effects among workers are usually not investigated or documented. ( See reproduction of his letter below.)

( Letter has been omitted)

Response EPA thank the commenter for the views and information provided which will be considered in carrying out the Agency planned activities. EPA believes the projects described in the Summary Response of this section respond positively to many of these comments. As stated in the response to EPA Log No. 8 in this section, EPA believes that a more practical and affordable approach to characterize human health impacts and that would yield results in a more timely manner would be from the projects described in the Summary Response to this section. For that reason, EPA at this time does not support epidemiological studies. Finally, EPA values the data and study results from all researchers and stakeholders as long as this information meets the standards of EPA's Data Quality Guidelines.

EPA Log # 33: Citizens for Sludge Free Land ( CFSL)

Comment CFSL agrees with Synagro Technologies Inc. that the references in the NRC report failed to include important studies. For example, the NRC report failed to reference the groundbreaking research of University of Georgia scientists that document the links between land application and adverse health effects in peer reviewed medical and technical journals. This omission is especially egregious because much of the information and many of the recommendations in the University of Georgia research were incorporated in the report, without giving the authors credit. Likewise, the EPA Response does not give credit to these researchers and their recommendations. USEPA, 2003d 86 Response Please see the response to Comment log No. 31. All relevant information will be considered.