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Standards for the Use or Disposal of Sewage Sludge; Agency Response to the National Research Council Report on Biosolids Applied to Land and the Results of EPA's Review of Existing Sewage Sludge Regulations
Note: EPA no longer updates this information, but it may be useful as a reference or resource.
[Federal Register: April 9, 2003 (Volume 68, Number 68)]
[Notices]
[Page 17379-17395]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr09ap03-64]
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ENVIRONMENTAL PROTECTION AGENCY
[FRL -7478-7]
Standards for the Use or Disposal of Sewage Sludge; Agency
Response to the National Research Council Report on Biosolids Applied
to Land and the Results of EPA's Review of Existing Sewage Sludge
Regulations
AGENCY: Environmental Protection Agency.
ACTION: Notice, with request for comment.
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SUMMARY: The Environmental Protection Agency is providing notice and
requesting public comment on the Agency's preliminary review of
regulations under the Clean Water Act governing the use and disposal of
sewage sludge. As part of this review, EPA commissioned the National
Research Council (NRC) of the National Academy of Sciences to
independently review the technical basis of the chemical and pathogen
regulations applicable to sewage sludge that is applied to land. In
July 2002, the NRC published a report entitled ``Biosolids Applied to
Land: Advancing Standards and Practices'' in response to the EPA's
request.
Today, the Agency is also announcing a strategy explaining how EPA
plans to respond to the recommendations in the NRC report. Today's
notice explains the rationale for the strategy and solicits public
comments on the strategy.
In addition, EPA is announcing the preliminary results of its
review of existing sewage sludge regulations under the Clean Water Act.
At this time, EPA has not identified any additional toxic pollutants
that warrant regulation in sewage sludge. The next step in identifying
chemicals that may warrant regulation is to conduct a screening
analysis of those chemicals for which adequate data and analytical
methods are available and for which there is evidence that they may
occur in sewage sludge. EPA plans to complete this screening analysis
by January 2004. The terms ``sewage sludge'' and ``biosolids'' are used
interchangeably in this notice.
DATES: EPA requests comments on all aspects of this notice. If you wish
to submit comments on this action, you must do so by July 8, 2003.
ADDRESSES: Send your comments to: Water Docket, Environmental
Protection Agency, Mailcode: 4101T, 1200 Pennsylvania Ave., NW.,
Washington, DC 20460, Attention Docket ID No. OW-2003-0006. Comments
may also be submitted electronically or through hand delivery/courier.
Follow the detailed instructions for providing comments in section B of
the SUPPLEMENTARY INFORMATION section.
FOR FURTHER INFORMATION CONTACT: Arleen Plunkett, U.S. Environmental
Protection Agency, Office of Water, Health and Ecological Criteria
Division (4304T), 1200 Pennsylvania Avenue, NW., Washington, DC 20460.
(202) 566-1119. plunkett.arleen@epa.gov.
SUPPLEMENTARY INFORMATION:
I. Additional Docket Information
A. How Can I Get Copies of This Document and Other Related Information?
1. Docket. EPA has established an official public docket for this
action
[[Page 17380]]
under Docket ID No. OW-2003-0006. The official public docket consists
of the documents specifically referenced in this action, any public
comments received, and other information related to this action.
Although a part of the official docket, the public docket does not
include Confidential Business Information (CBI) or other information
whose disclosure is restricted by statute. The official public docket
is the collection of materials that are available for public viewing at
the Water Docket in the EPA Docket Center, (EPA/DC) EPA West, Room
B102, 1301 Constitution Ave., NW., Washington, DC. The EPA Docket
Center Public Reading Room is open from 8:30 a.m. to 4:30 p.m., Monday
through Friday, excluding legal holidays. The telephone number for the
Public Reading Room is (202) 566-1744, and the telephone number for the
Water Docket is (202) 566-2426.
2. Electronic Access. You may access this Federal Register document
electronically through the EPA Internet under the ``Federal Register''
listings at http://www.epa.gov/fedrgstr/.
An electronic version of the public docket is available through
EPA's electronic public docket and comment system, EPA Dockets. You may
use EPA Dockets at http://www.epa.gov/edocket/ to submit or view public
comments, access the index listing of the contents of the official
public docket, and to access those documents in the public docket that
are available electronically. Once in the system, select ``search,''
then key in the appropriate docket identification number.
Certain types of information will not be placed in the EPA Dockets.
Information claimed as CBI and other information whose disclosure is
restricted by statute, which is not included in the official public
docket, will not be available for public viewing in EPA's electronic
public docket. EPA's policy is that copyrighted material will not be
placed in EPA's electronic public docket but will be available only in
printed, paper form in the official public docket. Although not all
docket materials may be available electronically, you may still access
any of the publicly available docket materials through the docket
facility identified in section A.1.
For public commenters, it is important to note that EPA's policy is
that public comments, whether submitted electronically or in paper,
will be made available for public viewing in EPA's electronic public
docket as EPA receives them and without change, unless the comment
contains copyrighted material, CBI, or other information whose
disclosure is restricted by statute. When EPA identifies a comment
containing copyrighted material, EPA will provide a reference to that
material in the version of the comment that is placed in EPA's
electronic public docket. The entire printed comment, including the
copyrighted material, will be available in the public docket.
Public comments submitted on computer disks that are mailed or
delivered to the docket will be transferred to EPA's electronic public
docket. Public comments that are mailed or delivered to the Docket will
be scanned and placed in EPA's electronic public docket. Where
practical, physical objects will be photographed, and the photograph
will be placed in EPA's electronic public docket along with a brief
description written by the docket staff.
For additional information about EPA's electronic public docket
visit EPA Dockets online or see 67 FR 38102, May 31, 2002.
B. How and to Whom Do I Submit Comments?
You may submit comments electronically, by mail, or through hand
delivery/courier. To ensure proper receipt by EPA, identify the
appropriate docket identification number in the subject line on the
first page of your comment. Please ensure that your comments are
submitted within the specified comment period. Comments received after
the close of the comment period will be marked ``late.'' EPA is not
required to consider late comments.
1. Electronically
If you submit an electronic comment as prescribed below, EPA
recommends that you include your name, mailing address, and an e-mail
address or other contact information in the body of your comment. Also,
include this contact information on the outside of any disk or CD ROM
you submit, and in any cover letter accompanying the disk or CD ROM.
This ensures that you can be identified as the submitter of the comment
and allows EPA to contact you in case EPA cannot read your comment due
to technical difficulties or needs further information on the substance
of your comment. EPA's policy is that EPA will not edit your comment,
and any identifying or contact information provided in the body of a
comment will be included as part of the comment that is placed in the
official public docket, and made available in EPA's electronic public
docket. If EPA cannot read your comment due to technical difficulties
and cannot contact you for clarification, EPA may not be able to
consider your comment.
i. EPA Dockets
Your use of EPA's electronic public docket to submit comments to
EPA electronically is EPA's preferred method for receiving comments. Go
directly to EPA Dockets at http://www.epa.gov/edocket, and follow the
online instructions for submitting comments. Once in the system, select
``search,'' and then key in Docket ID No. OW-2003-0006. The system is
an ``anonymous access'' system, which means EPA will not know your
identity, e-mail address, or other contact information unless you
provide it in the body of your comment.
ii. E-mail
Comments may be sent by electronic mail (e-mail) to ow-
docket@epa.gov, Attention Docket ID No. OW-2003-0006. In contrast to
EPA's electronic public docket, EPA's e-mail system is not an
``anonymous access'' system. If you send an e-mail comment directly to
the Docket without going through EPA's electronic public docket, EPA's
e-mail system automatically captures your e-mail address. E-mail
addresses that are automatically captured by EPA's e-mail system are
included as part of the comment that is placed in the official public
docket, and made available in EPA's electronic public docket.
iii. Disk or CD ROM
You may submit comments on a disk or CD ROM that you mail to the
mailing address identified in section B.2. These electronic submissions
will be accepted in WordPerfect or ASCII file format. Avoid the use of
special characters and any form of encryption.
2. By Mail. Send your comments to: Water Docket, Environmental
Protection Agency, Mailcode: 4101T, 1200 Pennsylvania Ave., NW.,
Washington, DC 20460, Attention Docket ID No. OW-2003-0006.
3. By Hand Delivery or Courier. Deliver your comments to: EPA
Docket Center, (EPA/DC) EPA West, Room B102, 1301 Constitution Ave.,
NW., Washington, DC 20460, Attention Docket ID No. OW-2003-0006. Such
deliveries are only accepted during the Docket's normal hours of
operation as identified in section A.1.
C. What Should I Consider as I Prepare My Comments for EPA?
You may find the following suggestions helpful for preparing your
comments:
1. Explain your views as clearly as possible.
[[Page 17381]]
2. Describe any assumptions that you used.
3. Provide any technical information and/or data you used that
support your views.
4. If you estimate a potential burden or costs, explain how you
arrived at your estimate.
5. Provide specific examples to illustrate your concerns.
6. Offer alternatives.
7. Make sure to submit your comments by the comment period deadline
identified.
8. To ensure proper receipt by EPA, identify the appropriate docket
identification number in the subject line on the first page of your
response. It would also be helpful if you provided the name, date, and
Federal Register citation related to your comments.
II. Abbreviations and Acronyms Used
AMSA--Association of Metropolitan Sewerage Agencies
BDMS--Biosolids Data Management System
CAFO--Concentrated Animal Feeding Operations
CDC--Centers for Disease Control and Prevention
CFR--Code of Federal Regulations
CWA--Clean Water Act
EC--European Community
EMS--Environmental Management System
EPA--U.S. Environmental Protection Agency
EQ--Exceptional Quality
EU--European Union
FTIR--Fourier Transform Infrared
GC/MS--Gas Chromatography/Mass Spectrometry
IAC--EPA Intra-Agency Committee for Biosolids
ICMA--International City/County Management Association
IRIS--Integrated Risk Information System
ISG--Information Sharing Group
LGEAN--Local Government Environmental Assistance Network
NBP--National Biosolids Partnership
NEBRA--New England Biosolids and Residuals Association
NPDES--National Pollutant Discharge Elimination System
NODA--Notice of Data Availability
NRC--National Research Council
NSSS--National Sewage Sludge Survey
ORD--Office of Research and Development
OW--Office of Water
PA--State of Pennsylvania
PCBs--Polychlorinated biphenyls
PCDDs/Fs--Polychlorinated dibenzo-p-dioxins/dibenzofurans
PCS--Permit Compliance System
PEC--EPA's Pathogen Equivalency Committee
POTW-Publicly Owned Treatment Works
PFRP--Processes to Further Reduce Pathogens
PSRP--Processes to Significantly Reduce Pathogens
QA/QC--Quality Assurance/Quality Control
QMRA--Quantitative Microbial Risk Assessment
RME--Reasonable Maximum Exposure
SSI--Sewage Sludge Incinerator
UA--University of Arizona, Water Quality Center
UCAL--University of California
UPA--University of Pennsylvania
USDA--United States Department of Agriculture
WEF--Water Environment Federation
WERF--Water Environmental Research Foundation
Table of Contents
I. What is the Legal Background of the Standards for the Use or
Disposal of Sewage Sludge?
II. What Requirements are Included in the Standards for the Use or
Disposal of Sewage Sludge (40 CFR Part 503)?
III. What is the Purpose of Today's Notice?
IV. What was EPA's Charge to the National Research Council?
V. What Were the National Research Council's Major Findings and
Recommendations Concerning Land Application of Biosolids?
VI. What Process did EPA Use to Address the NRC recommendations?
VII. EPA's Strategy for Responding to the NRC Recommendations
VIII.EPA Responses to the NRC Recommendations by Category
IX. How did EPA Conduct the Review of Part 503 Regulations under the
CWA Section 405(d)(2)(C)?
X. What are the Primary Issues for Public Comment?
XI. References
I. What Is the Legal Background of the Standards for the Use or
Disposal of Sewage Sludge?
EPA promulgated Standards for the Use or Disposal of Sewage Sludge
(40 CFR part 503) under section 405(d) and (e) of the Clean Water Act
(CWA), 33 U.S.C. section 1345(d), (e), as amended by the Water Quality
Act of 1987. In these amendments to section 405 of the CWA, Congress,
for the first time, set forth a comprehensive program for reducing the
potential environmental risks and maximizing the beneficial use of
sewage sludge. As amended, section 405(d) of the CWA requires EPA to
establish numerical limits and management practices that protect public
health and the environment from the reasonably anticipated adverse
effects of toxic pollutants in sewage sludge. Section 405(e) prohibits
any person from disposing of sewage sludge from publicly owned
treatment works (POTW) or other treatment works treating domestic
sewage for any use except in compliance with regulations promulgated
under section 405.
Section 405(d) calls for two rounds of sewage sludge regulations
and sets deadlines for promulgation. In the first round, EPA was to
establish numerical limits and management practices for those toxic
pollutants which, based on ``available information on their toxicity,
persistence, concentration, mobility, or potential for exposure, may be
present in sewage sludge in concentrations that may adversely affect
public health or the environment.'' CWA section 405(d)(2)(A). The
second round is to address toxic pollutants not regulated in the first
round ``which may adversely affect public health or the environment.''
CWA section 405(d)(2)(B).
EPA did not meet the timetable in section 405(d) for promulgating
the first round of regulations, and a citizen's suit was filed to
require EPA to fulfill this mandate, (Gearhart v. Reilly, Civ. No. 89-
6266- HO (D. Ore.)). A consent decree was entered by the court in this
case, establishing schedules for both rounds of sewage sludge rules.
EPA promulgated the first rule in 1993, 40 CFR part 503. 58 FR 9248
(Feb. 19, 1993) (``Round One''). For the second round (``Round Two''),
EPA identified 31 pollutants and pollutant categories not regulated in
Round One that EPA was considering for regulation. In November 1995,
EPA narrowed the original list of 31 pollutants to two pollutant groups
for the second round rulemaking: polychlorinated dibenzo-p-dioxins/
dibenzofurans (PCDDs/Fs) and dioxin-like coplanar polychlorinated
biphenyls (PCBs) (USEPA, 1996). The consent decree required the
Administrator to sign a notice for publication proposing Round Two
regulations no later than December 15, 1999, and to sign a notice
taking final action on the proposal no later than December 15, 2001.
(Gearhart v. Whitman, Civ. No. 89-6266-HO (D. Ore.)).
On December 15, 1999, the Administrator signed a proposal to
establish numerical limits for dioxins, dibenzofurans, and co-planar
PCBs (``dioxins'') in sewage sludge that is applied to the land and
proposed not to regulate dioxins in sewage sludge that is disposed of
in a surface disposal unit or fired in a sewage sludge incinerator. 64
FR 72045 (December 23, 1999). On December 21, 2001, the Administrator
gave final notice of EPA's determination
[[Page 17382]]
that numerical standards or management practices are not warranted for
dioxins in sewage sludge that are disposed of at a surface disposal
unit or incinerated in a sewage sludge incinerator. 66 FR 66228
(December 21, 2001). In that notice, EPA also announced that a final
action on the proposal to amend the Standards for the Use or Disposal
of Sewage Sludge for sewage sludge that is applied to the land would be
published at a later date. The consent decree in Gearhart v. Whitman
was amended to extend the deadline for final action on the land
application Round Two rulemaking from the original date of December 15,
2001, to a new date of October 17, 2003.
On June 12, 2002 at 67 FR 40554, EPA published a Notice of Data
Availability (NODA) containing new information relating to dioxins in
land-applied sewage sludge and requested public comments. Currently,
EPA is evaluating the public comments received on the NODA and will
consider these comments in formulating a final action on dioxins in
land-applied Sewage sludge by October 17, 2003.
II. What Requirements Are Included in the Standards for the Use or
Disposal of Sewage Sludge (40 CFR Part 503)?
As noted above, CWA Section 405(d)(2)(A) required the first round
of regulation to be based on ``available information on [the]
toxicity,
persistence, concentration, mobility, or potential for exposure'' of
toxic pollutants in sewage sludge. EPA published the Round One
standards (40 CFR Part 503) on February 19, 1993. These regulations
established requirements for the final use and disposal of sewage
sludge when it is: (1) Applied to the land for a beneficial purpose,
including in home gardens, (2) placed in a surface disposal site,
including biosolids-only landfills, and (3) incinerated.
For land application, Part 503 set numerical limits for nine heavy
metals in sewage sludge, established operational standards (described
below) to reduce or eliminate pathogens in sewage sludge and to reduce
vector attraction, and required management practices to restrict the
application rate and placement of sewage sludge on the land. Regarding
surface disposal, Part 503 set numerical limits for three metals in
sewage sludge, established requirements for the placement and
management of a surface disposal site, and established operational
standards to reduce or eliminate pathogens in sewage sludge and to
reduce vector attraction. For incineration in a sewage sludge
incinerator (SSI), Part 503 establishes limits for five metallic
pollutants in sewage sludge fired in a SSI and adopted standards under
the Clean Air Act for two additional metallic pollutants. The Agency
has also established performance standards for SSIs through an
operational standard for total hydrocarbons or carbon monoxide
emissions that controls numerous organic compounds found in the
emissions of sewage sludge incinerators. Part 503 also allows disposal
of sewage sludge in a municipal solid waste landfill in accordance with
40 CFR part 258. In addition, the final rule requires monitoring,
record keeping, and reporting. Standards apply to publicly and
privately-owned treatment works that generate or treat domestic sewage
sludge and to anyone who uses or disposes of sewage sludge.
The part 503 Standards consist of six elements designed to work
together to protect human health and the environment. These elements
are (1) numerical limits for certain pollutants, (2) management
practices, (3) operational standards, (4) monitoring, (5) record
keeping, and (6) reporting.
As an example, the land application provisions require a sewage
sludge preparer to gather information on the nutrient content of the
sewage sludge and pass this information along to the land applier in
order for the land applier to be able to apply the sewage sludge at a
suitable agronomic rate. Numerical limitations for land-applied sludge
are pollutant concentrations in sewage sludge or cumulative or annual
loading rates, based on multi-pathway exposure analyses and risk
assessments to protect public health. Management practices include
requirements, such as how the sewage sludge is to be placed on the land
or otherwise managed in the environment. An example is the prohibition
against applying sewage sludge to land closer than 10 meters from
waters of the United States. Operational standards are technology
requirements such as process descriptions and performance requirements
to reduce or eliminate pathogens from sewage sludge and reduce vector
attraction. These, together with required crop harvesting restrictions
and site controls, constitute the approach for the control of pathogens
in sewage sludge.
Monitoring of chemicals and pathogens in sewage sludge and
certification of certain actions by the preparer or land applier must
be performed at a frequency commensurate with the annual amount of
land-applied sewage sludge. Records must be kept of these monitoring
and certification activities at the locations where the monitoring/
certifications have occurred. Finally, the larger sewage sludge
preparers and land appliers must report this information to the
permitting authority at least annually.
EPA has amended part 503 several times since its initial
publication in February 1993. Following promulgation of the Round One
rule, several petitions for review were filed challenging various
aspects of the rule. In one petition, several mining and chemical
concerns challenged the land application molybdenum limits. EPA amended
the part 503 numerical standards for molybdenum to delete the
cumulative loading rate, annual loading rate, and the pollutant
concentration for molybdenum in sewage sludge to be land-applied. 59 FR
9095 (February 25, 1994). The ceiling concentration value for
molybdenum was retained. Also, in that Federal Register notice, EPA
added continuous monitoring of carbon monoxide as an alternative to
continuous monitoring of total hydrocarbons in the sewage sludge
incinerator requirements. In another case, Leather Industries of
America v. EPA, 40 F.3d 392 (D.C. Cir. 1994), the court remanded
several of the land application requirements. As a result of that
decision, EPA deleted all numerical standards for chromium in sewage
sludge to be land-applied and adjusted the Table 3 limit for selenium.
60 FR 54764 (October 25, 1995). EPA is considering further amendments
to address the issues remaining from the partial remand, as well as
other issues. EPA most recently amended Part 503 to make a number of
technical amendments, provide regulatory flexibility, and make the
sewage sludge incinerator standards self-implementing. 64 FR 42552
(August 4, 1999).
For a detailed discussion of the Part 503 Rule, see A Plain English
Guide to the EPA Part 503 Biosolids Rule (1994), which is available as
stated in the ADDRESSES section of the preamble. A copy of the Plain
English Guide is available at the website address http://www.epa.gov/
owm/mtb/biosolids/503pe/index.htm.
III. What Is the Purpose of Today's Notice?
Section 405(d)(2)(C) of the CWA calls on EPA to review the existing
sewage sludge regulations in part 503 at least every two years for the
purpose of identifying additional toxic pollutants in sewage sludge and
promulgating regulations for such pollutants consistent with the
requirements of section 405(d). Over the past decade, questions have
been raised over the
[[Page 17383]]
adequacy of the chemical and pathogen standards for protecting human
health. To help address the human health concerns and the requirement
for periodical reassessment of the Standards for Use or Disposal of
Sewage Sludge, the Agency commissioned the NRC to independently review
the technical basis of the chemical and pathogen regulations. The NRC
study took place between January 2001 and June 2002. In July 2002, the
NRC published a report entitled, ``Biosolids Applied to Land: Advancing
Standards and Practices'' in response to EPA's request. For a copy of
the full NRC report, visit our Web site at http://www.epa.gov/ost/
biosolids/nas/complete.pdf. The NRC identified a need to update the
scientific basis of Part 503 and provided approximately 60
recommendations.
In an agreement with the parties in Gearhart v. Whitman, EPA agreed
to publish a notice in the Federal Register stating how it will respond
to the NRC report recommendations and to seek public comments on its
planned response. EPA also agreed to review publicly available
information for the purpose of identifying additional toxic pollutants
in biosolids and to publish a notice providing the results of the
review and seek public comment. Today's notice fulfills this agreement.
IV. What Was EPA's Charge to the National Research Council?
EPA asked the NRC to conduct an independent evaluation of the
regulations and standards for chemical pollutants and pathogens in
biosolids that are land-applied. Specifically, the NRC was asked to
focus on the adequacy and appropriateness of the risk assessment
methods and data used by the Agency in setting regulatory requirements
to protect human health. The NRC convened the Committee on Toxicants
and Pathogens in Biosolids Applied to Land (``the committee''), which
conducted and prepared a final report. The Statement of Tasks included
the following:
1. Review the risk assessment methods and data used to establish
concentration limits for chemical pollutants in biosolids to determine
whether they are the most appropriate approaches. Consider the NRC's
previous (1996) review and determine whether that report's
recommendations have been appropriately addressed. Consider (a) how the
relevant chemical pollutants were identified, (b) whether all relevant
exposure pathways were identified, (c) whether exposure analyses,
particularly from indirect exposures, are realistic, (d) whether the
default assumptions used in the risk assessments are appropriate, and
(e) whether the calculations used to set pollutant limits are
appropriate.
2. Review the current standards for pathogen reduction or
elimination in biosolids and their adequacy for protecting public
health. Consider (a) whether all appropriate pathogens were considered
in establishing the standards, (b) whether enough information on
infectious dose and environmental persistence exists to support current
control approaches for pathogens, (c) risks from exposure to pathogens
found in biosolids, and (d) new approaches for assessing risks to human
health from pathogens in biosolids.
3. Explore whether approaches for conducting pathogen risk
assessment can be integrated with those for chemical risk assessment.
If appropriate, recommend approaches for integrating pathogen and
chemical risk assessments.
The NRC report, ``Biosolids Applied to Land: Advancing Standards
and Practices,'' described the work of the committee, stating that
``the committee searched for evidence on human health effects related
to biosolids exposure'' in its review of the risk assessments and
technical data used by EPA to establish the chemical and pathogen
standards and the management practices contained in part 503. The
report noted that ``the committee did not attempt to determine whether
the approaches used by EPA to set the 1993 biosolids standards were
appropriate at the time of their development, and the committee's
findings and recommendations should not be construed as either
criticism or approval of the standards issued at that time.''
V. What Were the National Research Council's Major Findings and
Recommendations Concerning Land Application of Biosolids?
The NRC committee concluded that ``there is no documented
scientific evidence to indicate that the part 503 rule has failed to
protect human health,'' but additional scientific work is needed to
reduce persistent uncertainty about the potential for adverse human
health effects from exposure to biosolids. The committee recognized
that land application of biosolids is a widely used, practical option
for managing the large volume of biosolids generated at waste water
treatment plants that otherwise would need to be disposed of at
landfills or by incineration. The committee also identified a need to
update the scientific basis of part 503 to (1) ensure that the chemical
and pathogen standards are supported by current scientific data and
risk assessment methods, (2) demonstrate effective enforcement of part
503, and (3) validate the effectiveness of biosolids management
practices. The NRC report focused on identifying how current risk
assessment practices and knowledge regarding chemical pollutants and
pathogens in biosolids can be used to update and strengthen the
scientific basis and credibility of EPA's biosolids regulations.
The NRC report contains four overarching recommendations: (1) Use
improved risk assessment methods to better establish standards for
chemicals and pathogens, (2) conduct a new national survey of chemicals
and pathogens in biosolids, (3) establish an approach to human health
investigations, and (4) increase the resources devoted to EPA's
biosolids program. These four overarching recommendations are discussed
in detail and supplemented by 53 individual recommendations contained
in Chapters 2-6 of the NRC report.
VI. What Process Did EPA Use To Address the NRC Recommendations?
Upon the release of the report, EPA established an Intra-Agency
Committee (IAC) to respond to the recommendations in the NRC report and
begin review of the existing Part 503 regulations to identify
additional toxic pollutants that may warrant future regulation,
pursuant to section 405(d)(2)(C). The IAC is comprised of EPA
representatives from a cross-section of environmental program offices
that are involved or interested in the biosolids program.
The IAC first developed an approach for responding to the NRC
report and conducting the section 405(d)(2)(C) review of existing
regulations. Activities for responding to the NRC report included
developing a matrix to identify and track each recommendation, grouping
the recommendations into eight categories based on subject area,
evaluating the recommendations individually and establishing
priorities, drafting initial responses by category, and developing a
strategy to carry out the activities identified in response to the NRC
recommendations. The approach for reviewing existing regulations to
identify additional toxic pollutants that may warrant regulation,
pursuant to section 405(d)(2)(C), is described in Section IX of this
notice.
As stated above, the IAC first prepared a matrix (Compilation of
National Research Council (NRC) Recommendations on Biosolids and
[[Page 17384]]
EPA Responses and Activities, USEPA 2002a) of all of the
recommendations contained in the NRC report (NRC 2002). The matrix
ensured that all recommendations were identified. Once in the matrix,
recommendations that were found to be similar in subject matter and
intent were placed in a framework to facilitate evaluation.
The Agency categorized the 57 recommendations (four overarching and
53 specific) into eight categories: (1) Survey, (2) Exposure, (3) Risk
Assessments, (4) Methods Development, (5) Pathogens, (6) Human Health
Studies, (7) Regulatory Activities, and (8) Biosolids Management. EPA's
response and planned activities are presented on a category-by-category
basis.
VII. EPA's Strategy for Responding to the NRC Recommendations?
EPA has identified three main objectives for attaining a better
understanding of biosolids and reducing the potential for, or reducing
the uncertainty related to, human health impact: (1) Update the
scientific basis of Part 503 by conducting research in priority areas,
(2) strengthen the biosolids program by evaluating results of
completed, ongoing, or planned studies both within and outside EPA, and
(3) continue ongoing activities for enhancing communication with
outside associations and with the public.
Major Short-Term Goals and Priority Actions During FY03 and FY04
Over the next two years, subject to available resources, the Agency
proposes to pursue biosolids activities in the following priority
areas:
1. Continue program implementation (regulatory, compliance, and
enforcement).
2. Evaluate the state-of-the-science and revise risk assessment
methodologies, as appropriate.
3. Review available data, track ongoing studies by researchers
outside of EPA, and identify information gaps. Initiate further field
studies as needed.
4. Continue ongoing/planned activities relative to exposure, risk
assessment, biosolids management, and analytical methods development.
5. Determine what pollutants, if any, warrant further regulation
under the CWA.
6. Design and begin conducting a targeted survey that uses
information obtained from published pollutant occurrence and effects
data, State occurrence data bases, and input received during the public
comment period.
7. Conduct a dialogue with other health-based Federal agencies,
such as CDC, on the possibility of cooperatively tracking incident
reports and investigating whether adverse human health outcomes can be
associated with biosolids exposure. The results could help the Agency
identify research gaps and, if appropriate, the need for a more
comprehensive research plan.
These activities would be aimed at implementing NRC recommendations
for reducing the potential for public health impact and updating the
scientific basis of Part 503.
Major Longer-Term Goals and Future Priorities (FY05 and Beyond)
The Agency's proposed long-term biosolids activities depend on
results of activities conducted in FY03/FY04 and available resources.
The following priority areas are aimed at implementing recommendations
for reducing the potential for public health impact:
1. Continue program implementation (regulatory, compliance, and
enforcement).
2. Update the scientific basis of Part 503 by using FY03/04
research or by conducting research in priority areas.
3. Strengthen the biosolids program by incorporating results of
completed, ongoing, or planned research activities both within and
outside EPA to possibly include:
? Quantitative microbial risk assessment.
? Improved understanding of exposure pathways/scenarios.
? Molecular tracking study.
4. Continue activities to establish partnerships and communicate
more effectively with other public health-based agencies, outside
associations and the public.
There is considerable relevant work being conducted by others
outside of EPA that may help inform and respond to the NRC
recommendations. Much of the external work that relates directly to
certain NRC recommendations is discussed in this notice and is being
used to improve the Agency's biosolids program.
The Agency's approach also includes promoting policy and procedural
guidance for ensuring and maximizing the quality of the information
disseminated. Completed studies and ongoing research, once compiled,
will be reviewed and evaluated for their contribution to EPA's
biosolids program in accordance with Information Quality Guidelines
(expressed in ``Guidelines for Ensuring and Maximizing the Quality,
Objectivity, Utility, and Integrity of Information Disseminated by the
Environmental Protection Agency'' USEPA 2002b). These guidelines stress
that information disseminated by EPA should adhere to a basic standard
of quality, including objectivity, utility, and integrity.
EPA has developed this notice using its best estimate of FY 2003
resources, which are not finalized, and based on the President's FY
2004 budget. The Agency has assumed the same level of funding for
future years, as is typically done.
VIII. EPA Responses to the NRC Recommendations by Category
A. Survey
1. Summary of Survey-Related NRC Report Recommendations
The NRC recommended that the Agency conduct a new national survey
of chemicals and pathogens in biosolids. A survey may provide feedback
for updating the science and technology of biosolids applied to land.
These data would then be used to identify pathogens and additional
chemicals for potential regulation and possibly deregulate those that
are not, or no longer, found. The NRC recommended several components in
designing a new national survey, including collecting data from State
program databases, determining the adequacy of analytical detection
methods and limits to support risk assessment, evaluating chemicals
eliminated previously due to lack of data (e.g., toxicity or exposure)
and new chemical categories (e.g., odorants, surfactants and
pharmaceuticals) not previously evaluated.
Further, the NRC recommended monitoring environmental media,
surveying for pathogens in both raw sewage sludge and treated sewage
sludge managed through the various processes recommended in Part 503,
assessing multiple species of certain metals (e.g., mercury and
arsenic) that have different toxicity profiles for human health,
including infants and children, and analyzing a broad spectrum of
pathogens in biosolids or environmental media adjacent to final use or
disposal sites.
In addition, the NRC recommended that the Agency verify the
adequacy of treatment and management practices. For example, to verify
that Class A and B (as described in Part 503) treatment processes
perform as assumed by engineering and design principles, EPA could
determine pathogen density and elimination across treatment processes
in biosolids and environmental media over time and examine management
practices to ensure that risk-assessment
[[Page 17385]]
principles are effectively translated into practice.
2. The Agency's Response to the Survey Category
How EPA Plans To Address NRC Survey Recommendations
The Agency believes that a comprehensive survey of pollutants in
biosolids may provide useful information, but it is not likely the most
pragmatic survey option available at this time. EPA has developed a
proposed survey approach based on experience gained from the 1988
National Sewage Sludge Survey (NSSS), limitations of available analytic
methods, knowledge of effects and routes of exposure, and suggestions
by the NRC, among other factors (see Planned Strategy for the Survey
Category below). The 1988 NSSS was ultimately limited in utility by
shortcomings in available analytical methods and limited information of
pollutant effects and/or means of exposure. While some advances in
these areas have been made since 1988, these same limitations still
exist for many pollutants, especially for pathogens and many of the new
or emerging chemicals identified by the NRC. Therefore, EPA has
concluded that a less comprehensive, more targeted, survey, to help
fill data gaps and inform decisions regarding further studies, may be
more useful to address uncertainties highlighted by the NRC.
Information developed by national and international experts on
pathogens and toxic chemicals may help produce a better informed survey
design. The Agency believes that using such information may produce
more valuable results than conducting a comprehensive national survey
at this time. EPA is first planning to develop and initiate a targeted
survey after considering the following sources of information:
Available data: The Agency has conducted a biosolids literature
search and is reviewing the information for relevant data on chemicals
and pathogens in biosolids. The literature search includes topics
related to a survey of chemicals and pathogens in biosolids, management
practices, and treatment efficacy. This information obtained may also
assist EPA in responding to other NRC recommendations. For example, the
Agency plans to use available information to prioritize future research
and, if necessary, modify biosolids management practices to reduce
risk.
Other sources of data include studies conducted by EPA regional
offices, States, and universities. For example, EPA Region 8 is
conducting a long-term study of biosolids addition to soil and the
potential effects on soil microbiology. The University of Arizona is
conducting research on airborne pathogen exposure at various times and
distance from biosolids application sites. Within the next six to nine
months, the Agency plans to review and assess such studies for their
contribution in determining the potential for exposure and adverse
human health impact from land-applied biosolids.
Studies: Ongoing EPA studies address many technical uncertainties
related to pollutants in biosolids. For example, the adequacy of
current analytical methods for selected priority pathogens and the
development and/or validation of new methods are also being studied. In
addition, field studies are being used to provide site-specific
occurrence data.
While study emphasis is being placed on pathogens to address areas
of uncertainty and public interest, selected chemicals are also being
addressed to help determine significant issues and identify information
gaps that remain to be addressed in these areas.
Planned Strategy for Designing a Targeted Survey
During the next fiscal year the Agency plans to initiate or
continue Studies devoted to:
1. Methods development and/or validation studies for enteric
viruses and helminth ova (see Methods Development).
2. Continuation and/or expansion of field studies to determine
environmental contaminant occurrence at selected sites (see Methods
Development and Pathogens Categories).
In addition, during the next 18 to 24 months, EPA is proposing to
design a targeted approach for a survey of pollutants that occur in
sewage sludge. New and existing information from sources such as
relevant published pollutant occurrence and effects data, State
occurrence databases, and input received during the public comment
period will be used to help in the development of the proposed survey.
To ensure the survey provides meaningful results and the effective
use of limited resources, EPA is considering restudying some of the
pollutants that were studied in the 1988-1989 NSSS. EPA is also
considering including some new and emerging chemicals, taking into
account the availability of adequate analytical methods and their
associated analytical costs. As a result, the Agency may only be able
to measure a limited number of pollutants.
B. Exposure
1. Summary of Exposure NRC Recommendations
The NRC made recommendations on how current exposure information
and updated conceptual exposure models can be used to update and
strengthen the scientific basis of the chemical and technology-based
pathogen standards. This category also includes recommendations to
evaluate exposure for the reasonable maximum exposure (RME) individual,
updating fate and transport models that might affect exposure
estimates, and conducting pre-planned exposure studies under certain
situations for specific exposure groups.
2. The Agency's Response to the Exposure Category
How EPA Plans To Address NRC Exposure Recommendations
Understanding human exposure to chemicals and pathogens, including
the concentrations and fate and transport through important exposure
pathways, is key for risk assessments supporting the Part 503 rule. As
discussed below in the Risk Assessment category, the Agency plans to
use a risk assessment framework to evaluate the priorities for
reassessing or updating underlying components (including exposure
assumptions) of previously conducted risk assessments. The Agency plans
to use this information to determine if new exposure and risk
calculations may be warranted for pollutants not previously assessed.
Such an evaluation would include a review of the exposure information
used in the Round 1 and Round 2 rules in light of new exposure
information.
To conduct this activity, the Agency plans to first collect and
review currently available exposure information from published
literature, Federal and State databases, the NRC report, and other
relevant sources. The Agency anticipates that some of the NRC
recommendations regarding exposure may be addressed in newly available
information, while others may require completion of ongoing studies.
The Agency plans to review currently available exposure information to
help identify data gaps and to inform decisions about future risk
assessments and the need for additional exposure studies.
In the mid-1990's, EPA conducted research on the land application
of biosolids to disturbed and contaminated sites requiring reclamation
or remediation. These studies, which focused on the ability of
biosolids to help improve soil properties and
[[Page 17386]]
establish sustainable vegetation cover on disturbed and highly
contaminated sites, also included identification and determination of
metals bioavailability in biosolids. The research was conducted to
strengthen our understanding of the potential health impacts of metals,
a particular focus during the development of the 1993 regulations.
Results of this work showed that assumptions regarding metals
availability used in earlier metals risk assessments were conservative.
The Agency plans to reevaluate these findings in context with current
practices and policies regarding exposure to metals in biosolids.
Exposure research: As part of a broader set of field studies, EPA
recently initiated, in partnership with USDA and the State of
Pennsylvania (PA), the planning of exposure-related research at five
biosolids production and/or application sites. These studies are
intended to gather site-specific information on current practices in
biosolids production and application, and to identify and evaluate the
fate of pollutants following biosolids application. Other objectives
for this research, depending on the site, include (1) characterization
of treated and untreated sludge (biological, physical, and chemical
characterization), along with sampling and analysis during land
application, (2) assessing the presence of pathogens, nitrogen, sulfur,
volatile organic compounds and particulates in air, (3) determining how
well the sewage sludge is disinfected as it moves through the different
stages of processing, and (4) determining pathogen content in Class B
sludge, once applied and following a period of natural attenuation.
Other related work is being conducted by the University of Arizona's
Water Quality Center.
Planned work is expected to begin in mid 2003. The plan is for
facility operations for these sites to be documented, including the
operation and performance of treatment process used to process sewage
sludge and produce Class A and Class B biosolids. Pathogen and chemical
occurrence data will also be collected at these sites. Proposed
measurements over time for the production and land application
processes may include total and volatile solids, pH, temperature, odor,
appearance (e.g., color, paste, liquid, powder), fecal coliforms,
Salmonella spp., Staphylococcus aureus, enteric viruses, and helminth
ova.
Because of concern over bioaerosols, air samples will be taken
prior to, during, and following land application at the point of
application and the fence line, for up to thirty days. Air sampling
will be conducted in collaboration with USDA to address pathogens,
chemicals, endotoxins, and particulates occurrence. Chemical and
pathogen concentrations in air represent an initial step towards
understanding the potential exposure of nearby communities. A
description of the proposed studies can be found in the Pathogens
category.
CAFO research: EPA is also conducting research on microorganisms
and chemicals at animal manure land application sites, composting
sites, and concentrated animal feeding operations (CAFOs). These
include studies on the concentrations of airborne pathogens, toxic
organic compounds, odorants, and particulates. The CAFO studies are
important, because pathogen and chemical air transport and fate for
animal manures resemble those for biosolids. The ongoing and proposed
studies are described in the Methods Development category in this
notice.
Planned Exposure Activities
EPA plans to continue its research partnership with USDA and the
State of PA and to study an additional five field application sites.
The Agency is exploring a plan to conduct a molecular pathogen
tracking exposure study as a follow-up to the PA/USDA/EPA study. This
study would focus on individuals who have received medical attention
and who suspect that they have been affected by biosolids application
practices. This study would analyze human biological monitoring samples
(e.g., feces, blood, or swabs from skin, ears, eyes, or throat) to
isolate potential causative agents, and genetic characterization would
be used to identify the potential source(s).
C. Risk Assessment
1. Summary of Risk Assessment NRC Recommendations
The NRC recommended that the Agency use improved risk assessment
methods to better assess risks and establish standards for chemicals
and pathogens under Part 503, since methods for conducting risk
assessments have evolved substantially since the 1993 regulations were
established. The recommendations also include reassessing standards for
chemicals currently in the Part 503 regulation using the latest
science. The NRC suggested that future risk assessments incorporate new
information on exposure, dose-response relationships, pathogen
survival, quantitative microbial risk assessment techniques, and
consideration of site-specific factors that may affect risk management
practices (e.g., odor). Recommendations were also made to involve
stakeholders in the risk assessment process and to examine biosolids
management practices to ensure that the underlying risk assessment
principles are effectively translated into practice.
2. The Agency's Response for the Risk Assessment Category
How EPA Plans To Address NRC Risk Assessment Recommendations Current
and Planned Risk Assessment Activities
For this notice, risk assessment is defined as the process of
identifying the potential adverse health effects associated with
environmental exposures to pollutants in biosolids, their severity, and
likelihood. Previously, EPA used a risk based approach for estimating
risks to human health and developing management practices to reduce
risks and set protective standards. When they were conducted, EPA's
assessments were based on state-of-the-science methods, information and
management practices. The NRC recommended areas where new or updated
health and exposure information, models, and risk assessment methods
may strengthen the Agency's assessments for land-applied biosolids.
Consistent with the recommendations of the NRC, EPA plans to
address the potential health hazards and exposures associated with land
application of biosolids using state-of-the-science risk approaches.
Specifically, EPA plans to reassess methods and data used for
previously evaluated pollutants, and apply these methods to new
pollutants. For example, risks from pollutants not previously assessed
due to a lack of toxicity, environmental fate, or exposure information,
will be reevaluated if new information is available. This effort is
expected to take place in FY03 and FY04. The Agency has assessed risks
to children and sensitive populations, and will continue that approach
in future assessments and reassessments.
The NRC also recommended that 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. The Agency's policy is to involve stakeholders
at various stages of policy development. The Agency intends to consider
how consultation with stakeholders should be included in developing
future sewage sludge risk assessments.
EPA, in conjunction with States and other Federal agencies, has
already been addressing local biosolids issues in a
[[Page 17387]]
few areas, and has used these opportunities to include stakeholders in
the process to further evaluate and improve the assessment and
management of biosolids. For example, stakeholders were involved in the
scenario development and regulatory processes of a recent study in
Pennsylvania. As part of this study, an informal information sharing
group was formed that included concerned citizens, local officials, and
contractors to assist the Agency in identifying stakeholder concerns
and ensuring transparency in the field study process.
For the ongoing Round Two land application rulemaking, EPA
conducted a revised risk assessment in response to public and peer
review comments on the 1999 Round Two proposal. This revised assessment
used a probabilistic approach instead of a deterministic approach to
yield information on the sources of variability and uncertainty in the
final risk estimates. The probabilistic approach used estimated values
for certain input variables over the range of observed data to estimate
the risks for the highly exposed population. This revised risk
assessment also used new inputs, which included a redefined ``highly
exposed individual,'' new pathways and mechanisms of exposure, new
exposure factors adopted from the latest EPA Exposure Factors Handbook,
a sensitivity analysis to determine the relative importance of the
input variables, and updated scientific information on the chemicals of
concern, dioxins. EPA redefined the ``highly exposed individual'' as a
member of a farm family that consumes 50 percent of his/her diet from
home-produced crops and animal products grown on his/her own biosolids-
amended land. EPA plans to use the Round Two risk assessment approach
as a starting point for evaluating the NRC's recommendations, including
the use of the reasonable maximum exposed (RME) individual for
improving future risk assessments.
EPA is currently funding and conducting research related to risk
assessment of biosolids. EPA is sponsoring research or has awarded
grants to the Water Environment Research Foundation (WERF) and others
to develop quantitative pathogen risk assessment methods and
approaches. EPA plans to conduct a comprehensive evaluation and peer
review of these results and, if deemed appropriate for use in assessing
risk from pathogens found in biosolids, the Agency would incorporate
these new risk assessment methods into any new or updated risk
assessment and update the part 503 rule as necessary.
Other studies and related activities that EPA is conducting or
sponsoring include the development of dose-response models for
quantitative risk assessment of selected pathogens and the development
of transmission models of pathogens and disease. These models are
currently being developed for drinking water and, EPA plans to evaluate
and, if appropriate, modify applicable models to be used in analyzing
pathogens in biosolids. In addition, research is being conducted with
USDA and various States on the extent of airborne concentrations of
pathogens, toxic compounds, odorants, particulates and bioaerosols. EPA
plans to evaluate the results of these studies for use in refining and
improving future biosolids exposure and risk assessments. Further
descriptions of these studies are provided in the pathogen section and
the action plan.
To further the state of the knowledge surrounding all aspects of
sewage sludge use and disposal, including improved risk assessments,
EPA is supporting a workshop scheduled for January of 2004 on the
``state of the science'' on land application of municipal and
industrial wastewater effluents, sewage sludge, and animal manures.
This workshop is being coordinated by the University of Florida and
will have numerous contributors from the Agricultural Research Service
of USDA, and academia, among other groups. New and additional
information on biosolids toxicities and environmental properties may
emerge from this workshop; once evaluated, this information may be used
in future risk assessment updates of the Part 503 Rule. The Web site
http://www.conference.ifas.ufl.edu/landapp/ 
contains
information concerning the upcoming workshop, as well as other relevant
information.
As discussed previously, EPA may use the risk assessment paradigm
to provide both a focused reassessment of certain previously addressed
pollutant risks, exposure pathways and risk assessment approaches, as
well as assessing pollutants which have not been previously evaluated
to effectively address the NRC risk assessment related recommendations
and the review required by Section 405(d)(2)(C) of the CWA. These risk
assessment activities will be initiated this year. This effort will be
developed and outlined by an interdisciplinary workgroup within EPA and
include external review of the analysis plan.
For this risk analysis, EPA is planning to focus on an evaluation
of those key pollutants and pathways which are likely to be of greatest
concern or where the new scientific developments may have the greatest
impacts. This may result in later updating the Round One risk
assessment models and re-evaluating selected pollutants, pathways and
endpoints and/or new pathways and endpoints not previously addressed.
EPA is planning a two-step process for addressing the NRC
recommendations with respect to risk assessments for pollutants in
sewage sludge. The first step would be to conduct a problem formulation
which would re-evaluate or assess methods, approaches and pollutants
considered in the Round One determinations, and any new qualitative
information for future pollutants. This problem formulation step would
include the development of exposure/risk assessment scenarios that
would be used to identify critical/key stressors, routes of exposure,
model application and data gaps. The primary focus of this effort will
be on areas having the greatest potential risks and uncertainties (e.g.
pathogens). The problem formulation will serve to eliminate those
stressors, scenarios, routes of exposure, and endpoints that need not
be evaluated further. It would retain those areas which are potentially
significant or require more study. The problem formulation would also
result in a research analysis plan that would not only identify risk
assessment activities but also prioritize research to address exposure
and risk management.
The second step would be to conduct quantitative risk assessments
and risk characterizations for key pollutants identified and
prioritized by the scenario/conceptual models, as appropriate. These
assessments would initially be screening level risk assessments. More
refined assessments would be conducted only on those pollutants and
pathways for which the screening-level assessment indicate significant
potential for risk. In conducting any risk assessments, screening or
comprehensive, EPA will, as appropriate, apply the most up-to-date
scientific information and risk assessment methodologies. In addition,
EPA proposes to continue its efforts to evaluate and develop new
methods for pathogen risk assessments and improved models for exposure
assessments.
EPA's proposed activities are to continue to track development of
methods for QMRAs and develop guidelines for assessing risk from
pathogens. In addition, EPA also plans to continue work on the
evaluation of data and models for improving exposure assessments. EPA
may also evaluate and
[[Page 17388]]
assess data and information related to multiple exposures, potential
contaminant interactions, and potential effects on sensitive sub-
populations, to the extent the state-of-the-science is available.
D. Methods Development
1. Summary of Methods Development NRC Recommendations
The NRC recommended that the Agency develop and standardize methods
for measuring pathogens and emerging chemicals in biosolids and
bioaerosols. Standardized methods could be used to provide measures of
performance and to verify that the Agency's management practices and
standards are reliable.
Specifically, the NRC recommended developing, standardizing, and
validating methods for pathogens in biosolids and bioaerosols (e.g.,
airborne pathogens). In addition, research that uses improved pathogen
detection technology, round-robin laboratory testing to establish
method accuracies and precision for pathogen concentrations in raw and
treated biosolids, mechanisms for incorporating new methodologies into
the verification process, and measures of performance that can be
monitored (e.g., concentrations of selected chemicals in exposure media
and human biological monitoring such as blood or urine of workers and
residents) could be considered useful in conducting and interpreting
future risk assessments and used to develop applicable risk-assessment
technologies.
2. The Agency's Response to Methods Development
How EPA Plans To Address NRC Methods Development Recommendations
For the methods development category, the Agency plans to focus its
resources on pathogens and chemicals associated with biosolids.
Validated analytical methods are necessary to support exposure
assessments for toxic pollutants and pathogens. Methods are needed for
determining the reliability of treatment processes, assaying pathogens
and chemicals in raw and treated biosolids, incident follow-up,
sampling environmental media, and human biological monitoring. Ongoing
or planned methods development activities in the Agency that address
the NRC recommendations follow.
Method Development Activities
Recently initiated EPA methods development work includes field
studies at five biosolids production and application sites. Currently
available analytical methods are being identified or in some cases
adapted for this study. A description of these field studies has been
provided in the preceding Exposure subsection of this notice.
Additionally, EPA is conducting field studies at animal manure land
application sites, composting sites, and concentrated animal feeding
operations (CAFOs). This research includes measurements of pathogens,
toxic organic compounds, odorants and particulates in the air near
CAFOs. Both the biosolids and CAFO studies include evaluation and
adaptation of analytical methods for selected pathogens and chemicals.
Results of these studies should assist the Agency in determining the
need for additional methods development research.
Open-path Fourier Transform Infrared (FTIR) spectrometry will be
used to measure volatile organic compounds from land application sites.
EPA is validating analytical methods for microorganisms cited in 40 CFR
Part 503. Fecal coliform methods have been validated, whereas
Salmonella methods are being validated. Methods and validation studies
for these two agents are expected to be published in 2004.
Planned Method Development Activities
As part of its field study programs, EPA plans to work with USDA to
investigate methods for measuring bacteria and viruses in air upwind
and downwind of biosolids land application sites. EPA is considering
developing and validating analytical methods for enteric viruses and
helminth ova, as well as chemical analytical methods for emerging
chemicals of potential concern in biosolids (e.g. pharmaceuticals).
E. Pathogens
1. Summary of Pathogen NRC Recommendations
The NRC recommended that the Agency review approaches for
developing microbial analytical methods and conducting microbial risk
assessments (Quantitative Microbial Risk Assessments) to analyze
sensitivity and to ascertain what critical information is needed to
reduce uncertainty about the risks from exposure to pathogens in
biosolids. According to the NRC, research activities that might improve
EPA's pathogen standards and reduce risk, or uncertainties concerning
risk, from pathogens following exposure to biosolids include
development, standardization and validation of detection and
quantification methods for pathogens and indicator organisms,
conducting research on vectors carrying pathogens and bioaerosols, and
conducting studies to determine whether site restrictions for Class B
achieve intended effects for pathogen levels. The NRC also recommended
that EPA not allow provisions for distributing Class A biosolids in
bags or other containers (weighing less than one metric ton) when they
do not meet pollutant concentration limits (i.e., all biosolids sold or
given away should be exceptional quality).
Other NRC recommendations include considering additional indicator
organisms (e.g., Clostridium perfringens) for use in regulations, as
well as funding, supporting and officially sanctioning the Pathogen
Equivalency Committee (PEC) as part of the Federal program. National
field and laboratory surveys to verify that Class A and Class B
treatment processes for pathogens perform as assumed by their
engineering and design principles could also be conducted.
Determinations could be made of pathogen density and elimination across
the various accepted treatment processes and in the biosolids or
environmental media over time, applying geographic and site-specific
conditions that affect pathogen fate and transport to determine the
effectiveness of site restrictions, buffer zones, and holding periods
for Class B biosolids. EPA may also consider further refining, and
directly correlating, stabilization controls to outcomes using
metabolic techniques (e.g., sour test, carbon dioxide metabolic
release, methane metabolic release).
2. The Agency's Response to the Pathogen Category
How EPA Plans To Address NRC Pathogen Recommendations
EPA currently uses a technology and management practices based
approach to minimize pathogen exposure. The Agency is considering
studies to better understand the measurement, control, and fate of
pathogens during the production and land application of sewage sludge.
Such studies include improved analytical methods, evaluation of
treatment and application processes, site-specific pathogen occurrence
studies, potential human health impacts, exposure assessment, and risk
assessment.
Certain pathogen studies are discussed in the Methods Development
subsection of this notice. Where other studies address several pathogen
issues (e.g., field studies, management, treatment, site restrictions),
they are briefly described below.
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Research: EPA has an ongoing biosolids research program focused on
selected pathogens, and is expanding this program during this fiscal
year. Future pathogen research will be determined by the results of
ongoing studies that will inform the Agency about significant issues
and information gaps that require additional work. Presently, the
Agency 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. Results of such research will assist the Agency in
determining where improvements may be needed.
Pathogen Activities
In June 2001, EPA and USDA sponsored a workshop on ``Emerging
Pathogen Issues in Biosolids, Animal Manures, and Other Similar By-
Products'' (USEPA 2003 in press). The workshop assembled experts in
biosolids and animal waste management to review the state-of-the-
science, resolve persistent and complex issues, and provide suggestions
for research. The workshop considered: 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.
A discussion of recently initiated EPA work concerning pathogens at
five biosolids and three animal manure production and/or application
sites is provided in the previous Exposure category.
The Agency has completed and is conducting additional studies on
exposure and occurrence of disease which are described in the Risk
Assessment and Human Health subsections of this Section VII. In a
collaboration with Duke University, EPA has also published a report on
the relationship between odor from animal and waste water residuals
processing facilities and land application sites and potential health
effects (Journal of Agromedicine, Volume 7(1), 2000, ISSN: 1059-924X).
The report summarizes the state of knowledge on ambient odor health
effects with emphasis on animal manure and biosolids odor emissions.
Potential mechanisms for health symptoms, methods for validating health
symptoms, presence of odor, and efficacy of odor management are
discussed. The importance of health effects was found to be dependent
upon a number of factors, and health impacts may be minimized using
odor remediation methods.
The University of Arizona's, National Science Foundation, Water
Quality Center (http://www.wqc.arizona.edu) has conducted, and is
planning to conduct, pathogen studies in biosolids including: (1) Air
transmission of pathogens from land application, (2) potential
occurrence of Staphylococcus aureus, (3) fate and transport of
pathogens, and (4) risk assessments for pathogens in land applied
biosolids. These studies will evaluate various application sites,
terrain, climate, and potentially affected nearby populations. The
researchers involved in this study plan to model the transmission of
pathogens to estimate exposure for nearby human populations, which may
ultimately allow the development of predictive risk assessment
protocols. EPA will monitor these studies as they develop over at least
the next two years to determine their relevance to the National
biosolids program.
EPA's Pathogen Equivalency Committee (PEC): The Agency formed and
has supported the PEC since 1985. PEC members provide guidance to
applicants, permitting authorities and members of the regulated
community on sampling and analysis issues related to meeting the
subpart D requirements of part 503 (pathogen and vector attraction
reduction). The PEC currently consists of representatives from EPA and
the Centers for Disease Control and Prevention (CDC). The members have
expertise in bacteriology, virology, parasitology, wastewater
engineering, medical and veterinarian sciences, statistics, and sludge
regulations. The PEC evaluates and supports development of alternative
treatment technologies by consulting with local communities, States,
industry and others stakeholders. The PEC provides information on
biosolids processes, contaminant occurrences, and exposure, and assists
EPA regions, States, and the regulated industry with questions about
equivalency for Processes to Significantly Reduce Pathogens (PSRP) and
Processes to Further Reduce Pathogens (PFRP) under 40 CFR part 257 and
part 503. If the PEC recommends that a process is equivalent to PSRP or
PFRP, the operating parameters and any other conditions critical to
adequate pathogen reduction are specified.
The Water Environment Research Foundation (WERF), with
contributions from EPA, is funding a diverse research program to
support the wastewater treatment industry. An important part of their
program has been supporting research on biosolids that has been aimed
at reducing uncertainties and hence is significant with respect to the
NRC recommendations. Treatment plant residuals and biosolids, including
pathogen issues, have consistently ranked among the top five priorities
for WERF subscribers over the past decade. WERF biosolids research
entails more than 40 basic and applied projects to reduce
uncertainties, better manage biosolids, assess public perception of
risks, and develop strategies for biosolids treatment and management.
Much of WERF's research is focused on the beneficial uses of biosolids.
The Research of particular interest includes methods for rapidly
detecting pathogens. EPA plans to continue to review and evaluate such
research projects as they are completed to determine their relevancy to
the national biosolids program.
Other studies supported by WERF are intended to determine biosolids
land application rates. Phosphorus overload in animal manure and
biosolids is a particular concern. These studies are evaluating
phosphorus bioavailability and Class A and Class B pathogens to
determine potential impact on groundwater and other environmental
media. WERF is convening a biosolids research summit in the summer of
2003. A WERF pre-summit will provide training about mutual gains
activities and joint fact finding, and will develop a protocol for
guiding the assistance of an information sharing group (comprised of
the concerned citizens, as well as stakeholders) in recommending WERF-
sponsored research and oversight needs. EPA plans to collaborate with
WERF and the USDA to sponsor an international conference on sustainable
land application for municipal and industrial effluents, manures,
biosolids and other non-hazardous wastes. The conference, scheduled for
January 2004, will provide information and perspectives on research
gaps and needs. Detailed information on the WERF biosolids research
program may be accessed at http://www.werf.org.
Planned Pathogen Activities
Quantitative Microbial Risk Assessment (QMRA): EPA and WERF are
funding research termed ``QMRA'', as described in ``A Dynamic Model to
Assess Microbial Health Risks Associated with Beneficial Uses of
Biosolids'' (WERF 2003, Cooperative Agreement No. CR-825237). The
organizations involved in this research include WERF, the University of
[[Page 17390]]
California at Berkeley, and Eisenberg, Olevieri and Associates. The
document describing this research also presents a methodology for
assessing exposure and risks to human health from pathogens in
biosolids. The present methodology provides initial screening for a
given scenario, identifies broad conditions for high and low risk
situations, and estimates where more data are needed. Future work
(beyond 2004) may focus on applying this methodology to more refined
scenarios. Such validation activities will assist EPA in developing
microbial risk assessment guidelines, subject to available resources.
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, studies of wastewater treatment sludge
stabilization during biosolids production to reduce odors and vectors,
and the use of pilot-scale treatment units to optimize sludge treatment
techniques for pathogen and chemical control.
F. Human Health Studies
1. Summary of Human Health NRC Recommendations
The NRC recommended that the Agency conduct response incident
investigations, targeted exposure surveillance, and well-designed
epidemiological investigations of exposed populations. Data from these
studies would be used to provide a means of documenting whether health
effects exist that can be linked to biosolids exposure.
The NRC also recommended that preplanned exposure assessment
studies characterize exposure of workers and the general public who
come into contact with biosolids either directly or indirectly. Such
studies could include the identification of microorganisms and
chemicals, the selection of measurement methods for field samples, and
the collection of adequate samples in appropriate scenarios.
Further, the NRC recommended that epidemiological studies of
biosolids use be designed to provide evidence of a causal association,
or lack thereof, between biosolids exposure and adverse human health
effects. These studies could include an assessment of the occurrence of
disease and an assessment of potential exposures. Because large scale
and comprehensive epidemiological studies are expensive and require
extensive data analysis, priority could be given to studies that can
help reduce uncertainty.
2. The Agency's Response to the Human Health Studies Category
How EPA Plans To Address NRC Human Health Studies Recommendations
At this time, the Agency does not plan to conduct an
epidemiological study, as discussed in the NRC report. As noted by the
NRC, comprehensive epidemiological studies are complex, time consuming,
and require substantial additional funding. The Agency may assess the
future need for epidemiological studies, but believes targeted human
health studies (e.g., those of focused scope, such as exposure to
pollutants via aerial transport and incident investigations) over the
short-term might better address potential human health impact and
persistent uncertainties surrounding exposed populations. These studies
could help assess the potential airborne exposure to pollutants and
could help determine whether incidents are occurring following
biosolids exposure. Targeted exposure and human health studies could
also help inform the design of any future epidemiological studies,
should they prove necessary. Results from targeted studies would also
allow the Agency to communicate with other public health-based federal
agencies regarding human health exposure and epidemiological studies.
Planned Human Health Activities
Targeted Human Health Investigations: The Agency's primary
objective is to characterize pollutants and microbial agents present in
biosolids, as well as any associated human exposure pathways, that may
have the greatest potential to adversely impact human health.
Specifically, the NRC sees an immediate need for a systematic approach
for investigating claims of disease or illness following biosolids
exposure. Regulators, sewage sludge processors, and land appliers must
be capable of responding rapidly to such reports. The Agency is
investigating the possibility of developing a process for timely
notification, recording, and tracking incident reports in collaboration
with the Centers for Disease Control and Prevention (CDC). The Agency
has initiated preliminary discussions with the CDC to discuss possible
mechanisms for recording and tracking biosolids related disease
incidents.
The University of Arizona's National Science Foundation, Water
Quality Center, may also join cooperatively in the USDA/EPA/State of PA
study to evaluate risk from exposure to pathogens, particulates,
endotoxins, and odors from farm fields and other agricultural and
silvicultural settings upon which biosolids, animal manures, and other
organic amendments have been applied. These cooperative studies will
evaluate various application sites, terrain, climate, placements of
receptor populations and downwind ambient air concentrations of
pathogens and volatile organic chemicals near residents. The Agency
plans to evaluate if the collected data can be used to develop models
for estimating exposure of human populations downwind of these sites,
which might then be used in predictive risk assessment applications.
G. Regulatory Activities
1. Summary of Regulatory NRC Recommendations
The NRC recommended that EPA revise or develop regulatory criteria
for biosolids in a timely fashion and identify additional regulatory
mechanisms to better protect human health and the environment from the
exposure to land-applied biosolids. This recommendation includes the
following components: a review of biosolids protocols used by other
nations, adoption of national standard treatment design criteria, a
refinement of stabilization controls correlated to outcomes using
metabolic techniques, development of molybdenum standards, development
of a quantitative microbial risk assessment (QMRA) to establish
regulatory criteria for pathogens, studies to determine whether the
management practices specified in the Part 503 rule achieve their
intended effect, provisions for the distribution of Class A biosolids
weighing less than 1 metric ton (i.e., the NRC recommends that all
biosolids sold should be exceptional quality (EQ)), and the elimination
of exemptions for nutrient management and site restrictions for land-
applied EQ biosolids.
The NRC also recommended that EPA consider additional risk-
management practices when revising the part 503 rule. Considerations
should include limitations on holding or storage practices, slope
restrictions, soil permeability and depth to groundwater, and setbacks
to residences or businesses, surface water, and drinking water
supplies.
[[Page 17391]]
2. The Agency's Response to the Regulatory Category
How EPA Plans To Address NRC Regulatory Recommendations
Ongoing Regulatory Activities
New Standards: As previously mentioned in Section II above, EPA
vacated the numeric standards for molybdenum in sewage sludge as a
result of litigation. EPA has conducted a literature search of new
environmental properties information for molybdenum in land-applied
biosolids. Following review of this new information, EPA will determine
its applicability as the basis for re-proposing molybdenum standards
for land-applied sewage sludge. EPA is planning to complete this review
in 2003.
EPA also has information indicating that virtually no biosolids
products are sold or given away in bags or other containers unless they
comply with the pollutant concentrations for the nine metals currently
regulated and the pathogen and vector attraction reduction
requirements, which allows these products to be classified as
exceptional quality (EQ) as described in the EPA guidance (USEPA,
1994). EPA plans to evaluate the data during the current year to
determine whether to amend part 503 to eliminate the non-EQ Table 4
alternative for selling and distributing biosolids products that are
sold or given away in bags or other containers weighing less than one
metric ton.
Standardized Management Practices: Part 503 is designed to protect
public health through compliance not only with numerical criteria for
pollutants found in biosolids, but also with operational standards for
pathogen and vector attraction reduction. These operational standards
are performance based, based on operational goals for specified
reduction, to enable elimination of pathogens and vector attraction
reductions in sewage sludge through various engineering designs,
processes and equipment. EPA believes that such means are appropriate
for achieving environmental performance while encouraging efficient,
cost-effective, and innovative systems and approaches.
The establishment of national standard treatment design criteria
may not result in application of the most efficient site-specific
practices for protecting public health. The additional management
practices recommended by the NRC are linked to site-specific, or local-
level, conditions. Examples include topography, soil characteristics,
climate, population density, land-use, depth to groundwater, and
proximity to surface waters. States and local jurisdictions will have
better knowledge of local conditions, and are in a better position to
establish additional management practices to augment the protectiveness
of the part 503 Standards. However, EPA also plans to evaluate such
practices to determine if additional requirements or improvements in
the Part 503 Rule are warranted.
Regulations from Other Nations: EPA generally considers relevant
and available information and protocols from other nations to augment
and inform its decisions. When standards are available, such as the
Canadian standards for sewage sludge, these have provided the Agency
with valuable new perspectives and insights into the scientific,
technical, and societal basis for the development and implementation of
sewage sludge regulations. However, there are fundamental scientific
and programmatic differences between certain international sewage
sludge standards and EPA's standards for the use or disposal of sewage
sludge in 40 CFR part 503.
The Part 503 Standards are based on information for pollutants
found in sewage sludge, and are risk-based as directed by section
405(d) of the Clean Water Act. As such, the Part 503 Standards consist
of numerical limits with adequate margins of safety to protect public
health and the environment. The Part 503 numerical standards are based
on a conservative set of exposure pathway and risk assessment
assumptions.
In contrast, international sewage sludge standards are based on
differing legal frameworks. Therefore, sewage sludge regulation
promulgated by some other countries may not be comparable to EPA's
authority or standards under section 405 of the CWA. However, numerous
other countries have supported the quantitative risk assessment
approach and have often adopted Part 503 limits for regulating
biosolids.
Planned Regulatory Activities
Studies: As part of its field studies in 2004, EPA is planning to
evaluate certain Class B disinfection processes including the natural
attenuation of pathogens that occurs while the sludge is on or in the
soil for the site restriction periods stated in the current regulations
(40 CFR 503.32(b)(5)). Treatment processes that are expected to be
evaluated include anaerobic digestion and lime addition. Site
restrictions to be studied include limitations on how soon agricultural
activities can occur after biosolids application. In determining the
efficacy of current management practices, ways to improve them may also
be identified. This research will be initiated in 2003.
H. Biosolids Management
4. Summary of Biosolids Management NRC Recommendations
The NRC recommended that the Agency increase the resources devoted
to its biosolids program and expand biosolids management activities.
Specific recommendations were made to increase funding to States to
implement programs, fund, support, and officially sanction EPA's
Pathogen Equivalency Committee (PEC) as part of the EPA biosolids
program, and strike a balance between expending resources on new site-
specific data collection and expending resources to model and assess
risk using existing information.
The NRC also recommended biosolids management activities in the
following areas: expand and strengthen the oversight program, track
allegations and sentinel events of adverse health effects from exposure
to land-applied biosolids, and conduct studies to determine whether the
management practices specified in Part 503 achieve their intended
effect.
Furthermore, the NRC recommended that the Agency develop a
procedural framework to implement human health investigations and to
verify that (1) treatment technologies for pathogen control are
effective (quality control), (2) chemical standards are met (compliance
audits), and (3) unanticipated hazards are identified.
2. The Agency's Response to the Biosolids Management Category
How EPA Plans To Address NRC Biosolids Management Recommendations
Biosolids Management Activities
Overview: At EPA Headquarters, the biosolids regulatory staff
within the Office of Water has been increased recently. The new staff
positions will be devoted to regulatory development, Part 503 updates,
and implementation activities. There is also an enforcement or
compliance presence in each of the EPA Regional Offices for following
up on phone calls and complaints received from the public, and
initiating Agency enforcement actions, as appropriate.
States have their own oversight programs, some of which are quite
comprehensive. There are a total of about 150 full time equivalent
State employees assigned to their respective biosolids programs. Five
States have
[[Page 17392]]
been authorized by EPA to administer the part 503 program, and 15
additional States are at various points in the authorization process.
National coordination of State, regional and Headquarters biosolids
programs are achieved via an annual national meeting.
EPA continues to meet its statutory obligations under the Clean
Water Act (CWA) pertaining to sewage sludge. The Agency continues to
believe that land application of biosolids is an appropriate choice for
communities, when conducted in compliance with EPA regulations. Given
present scientific knowledge, EPA has based the allocation of resources
to biosolids compliance and enforcement on its assessment of the
relative risks to public health and the environment that are posed by
biosolids.
Regions and States have the flexibility and responsibility to
address situations where compliance assistance and enforcement actions
to address biosolids are appropriate and necessary. EPA has taken
enforcement actions and/or appropriate administrative remedies to
address biosolids violations of 40 CFR part 503 and will continue to
take actions to address instances where biosolids pose an imminent and
substantial endangerment to human health or the environment. EPA will
reconsider resources devoted to biosolids if additional research and
science demonstrate greater risk.
To assist the States and Regions in their oversight of the
biosolids program, EPA has, either in place or in development, tools to
assist and promote compliance with biosolids regulatory requirements.
The National Pollutant Discharge Elimination System (NPDES) Compliance
Inspection Manual, which is used by EPA and State inspectors to perform
inspections in the field, includes a ``Sludge (Biosolids)'' chapter
(Chapter 10). This manual has just undergone major revisions and
updating by a Headquarters and regional workgroup; the Manual is being
distributed as a final draft for regional and program office review.
Electronic training modules, including a module for biosolids
inspections, are planned to be available shortly after the release of
the revised manual, in Summer 2003.
Additionally, there are two compliance assistance web sites, which
are available for biosolids compliance studies, information and tools,
and for links to other sites with pertinent biosolids compliance
information. One is the National Environmental Compliance Assistance
Clearinghouse at: http://cfpub.epa.gov/clearinghouse/. This site is a
searchable clearinghouse of compliance assistance materials. The second
Web site is the Local Government Environmental Assistance Network
(LGEAN) at http://www.lgean.net. This on-line compliance assistance
center, which focuses on local government environmental requirements,
is operated by the International City/County Management Association
(ICMA), and has six other partners representing local government.
In the area of data systems, EPA is continuing to work with States
as it modernizes the Permit Compliance System (PCS) to allow for more
effective program oversight. While PCS is the national data system for
the NPDES permit program, it currently requires only limited biosolids
data. As part of the PCS modernization, a separate workgroup (including
States and EPA) was devoted to the data needed to manage the biosolids
program. This workgroup examined data in State systems, Biosolids Data
Management System (BDMS) and PCS, and considered incorporating BDMS
into PCS. The recommendations of this workgroup, endorsed by the PCS
Executive Council, was not to incorporate or link BDMS, but rather to
add data elements to PCS to improve tracking and oversight of the
biosolids program.
The BDMS is another source of biosolids data. It was developed in
the late 1990s by Region VIII to track biosolids quantity, quality,
use, and disposal practices in the Region VIII states. While not the
national system of record for biosolids, BDMS is a tool for
municipalities in which they can enter data themselves and use the BDMS
to develop reports for states, EPA and for citizen review. The BDMS is
also a valuable management tool and can be used to record information
about reported incidences associated with biosolids land application.
The BDMS is available at: http://www.treeo.uf/.edu/water/
bdmsQuestionnaire.asp. Current BDMS users include some EPA Regional
offices, States, users of biosolids, contract land appliers, and POTWs
throughout the U.S. and Canada. EPA is continuing to assess the
potential of upgrading BDMS as a management tool that can link with
established states and the Federal PCS system.
Research by the Water Environment Research Foundation (WERF) is
described in the Pathogen and the Human Health Studies categories. WERF
also supported a study by the New England Biosolids and Residuals
Association (NEBRA) looking at the importance of establishing
relationships among researchers, federal government and concerned
citizens. This research included a survey on public perceptions and
what people know about biosolids, what their concerns are and whether
their concerns are being addressed adequately. The study's aim is to
suggest ways that regulators and people can work together. A report is
due out by mid 2003.
This and other projects will help the Agency gain a better
understanding of public perception issues, values, and expectations.
EPA can then identify the most effective communication approaches to
ensure understanding of the importance of, and need for, proper
biosolids management
Science and Public Outreach: Because of varying resources and
diverse local circumstances, risk communication practices vary widely
throughout the United States. The Agency's risk communication programs
are aimed at improving public awareness of the issues and to achieve
exposure reductions where needed. Embodied in all of the priorities for
action described in this biosolids strategy is a need to foster public
awareness of the issues surrounding biosolids use and exposure. Through
the activities and organizations mentioned below, EPA is committed to
improving the effectiveness of risk communication methods at national,
regional, and local levels.
An Information-Sharing Group (ISG) has been established based upon
the concepts developed in WERF studies concerning joint fact-finding
research. The ISG is comprised of concerned citizens, health
scientists, municipal operators, a farmer, biosolids managers, and
input from State and Federal regulatory agencies. The ISG has been
established to work jointly with about 25 scientific experts in a large
cooperative study of odor, particulates, pathogens, and endotoxins in
the air around biosolids and animal manure land application sites.
Currently the researchers are from EPA, USDA, the State of PA, and
several other organizations. WERF has efforts underway to expand the
use of such information-sharing in other research projects.
The National Biosolids Partnership (NBP) is a 48 member alliance
formed in 1997 with AMSA (Association of Metropolitan Sewerage
Agencies), WEF (Water Environment Federation, and EPA (U.S.
Environmental Protection Agency). Through partnering with producers,
service contractors, users, regulatory agencies, universities, the
farming community, and environmental organization, the goal of the NBP
is to advance environmentally sound and accepted biosolids management
practices.
[[Page 17393]]
Through a voluntary Environmental Management System (EMS), being
developed for biosolids by the National Biosolids Partnership (NBP),
EPA continues to provide the public with educational information, based
on the best science, about the recycling and disposal of biosolids. EPA
strongly supports the ongoing efforts of the NBP to develop the EMS and
to provide correct and timely information and community-friendly
practices that could be followed via its new communications system. The
EMS program supports local agencies to find ways to meet and go beyond
what is required in state and federal regulations. About 45
municipalities are now pilot-testing their biosolids EMS programs based
upon a blueprint developed by the NBP. Several of these municipalities
will be ready to undergo an independent third party audit of the EMS
program later this year (2003). Municipalities involved in the
voluntary EMS program are reporting benefits they have achieved. They
report that their participation in the EMS program has resulted in more
efficient operation, reduced odors in biosolids, less intrusive
transport of the biosolids to land application sites, better
communication, and meaningful involvement of the public. The Agency
plans to continue supporting NBP activities and working with
municipalities on expanding the use of EMS programs in biosolids
management. Two NBP Web site address that present relevant biosolids
information are http://www.biosolids.org and http://
biosolids.policy.net/emsguide/manual/goodpractmanual.vtml.
Pathogens subsection. The PEC is instrumental in the development and
evaluation of regulatory-related initiatives. EPA will continue to
support and evaluate the activities of the PEC.
State Regulations: 40 CFR part 503 sets minimum standards for the
use or disposal of sewage sludge. State requirements may be more
restrictive or administered in a manner different from the Federal
regulation. In all cases, users and disposers of biosolids must comply
with the most restrictive portions of both the Federal and State rules.
In most cases, the part 503 rule is self-implementing; users must
comply with part 503 rule, even if they have not been issued a permit
covering sewage sludge use or disposal. EPA or States can take
enforcement actions directly against persons who violate part 503
requirements. In situations where States and others are addressing such
issues, EPA plans to use those opportunities to further evaluate and
develop the tools to improve the assessment and management of sewage
sludge.
Planned Biosolids Management Activities
The priority activities for biosolids presented in this response
were evaluated in the larger context of other Agency priorities. The
purpose of listing planned activities is to illustrate the Agency's
future direction based on current information. Given the activities
spelled out in this response, EPA's goal over the next two years is to
complete studies and other activities, follow external research, and
review available information. The Agency's longer-term goal is to
assess results from completed and ongoing activities to determine
further research needs. Implementation of various activities will be
considered by the relevant EPA Offices and Regions in future priority
setting activities.
IX. How Did EPA Conduct the Review of Part 503 Regulations Under the
CWA Section 405(d)(2)(C)?
Section 405(d)(2)(C) of the Clean Water Act requires that EPA
review the sewage sludge regulations ``for the purpose of identifying
additional toxic pollutants and promulgating regulations for such
pollutants consistent with the requirements'' of section 405(d). EPA
has promulgated regulations in 40 CFR part 503 setting numeric
standards for certain toxic pollutants in sludge, requirements for
pathogen and vector attraction reduction, and operational standards for
emissions from sewage sludge incinerators.
As explained in section IV above, EPA commissioned the NRC study of
existing sewage sludge land application regulations for the purpose of
strengthening the scientific basis of its review under section
405(d)(2)(C). In an agreement with the parties in Gearhardt v. Whitman,
EPA agreed to publish a notice seeking public comment on its proposed
response to the NRC recommendations and the results of its 405(d)(2)(C)
review. In conducting this review, EPA committed to review and evaluate
publicly available information, such as sampling data, scientific
studies, and other analysis and information taken from a wide range of
national and international public and private sources.
In fulfilling this commitment, EPA has performed a comprehensive
assessment of the availability of data on chemicals that have been
detected in or in some way linked to sewage sludge. EPA reviewed Rounds
One and Two screening histories; collected and conducted a preliminary
review of publicly available information on chemical toxicity,
environmental properties such as mobility and persistence, and
concentration; identified chemical pollutants for which appropriate
analytical methods and human health benchmarks are available; and made
preliminary determinations regarding sufficiency of information for
risk-based screening analyses. The results of this review are available
in the docket (USEPA, 2003e).
At this time, EPA has not identified any additional toxic
pollutants that warrant regulation in sewage sludge. The next step in
identifying toxic pollutants that may warrant regulation is to conduct
a screening analysis of those chemicals for which adequate data and
analytical methods are available and for which there is evidence that
they may occur in sewage sludge. EPA plans to complete this screening
analysis by January 2004. In addition, EPA is continuing to seek
additional information to fill data gaps for those chemicals for which
adequate data for the screening analysis is not yet available and would
welcome any relevant data from commenters.
The Agency began its review under section 405(d)(2)(C) by first
reviewing the complete list of pollutants that were considered in
developing the Round One rule and Round Two proposal. For Round One,
EPA conducted a National Sewage Sludge Survey (NSSS) in 1988-1989,
which included an analysis of 411 pollutants. These 411 pollutants
included, among others, every organic chemical including pesticide,
dibenzofuran, dioxin and PCB analytes for which EPA had gas
chromatography and mass spectrometry (GC/MS) standards (58 FR 9268-
9269). Of the original 411 pollutants, EPA promulgated numeric
standards in Round One for 10 pollutants (metals) in land-applied
sewage sludge, three pollutants (metals) in sewage sludge placed in
surface disposal units, seven pollutants in sewage sludge fired in
sewage sludge incinerators (SSIs), and an operational standard for
total hydrocarbons (or alternatively carbon monoxide) emitted from
SSIs.
These same 411 pollutants were the starting point in 1995 for
identifying pollutants for developing a Round Two regulation. EPA
conducted a preliminary screening analysis which resulted in an
identification of 31 pollutants for potential regulation in Round Two.
These 31 pollutants were the subject of a comprehensive hazard
identification study, which narrowed the list to dioxin, dibenzofurans
and
[[Page 17394]]
coplanar polychorinated biphenyls (PCBs).
Many of the original 411 pollutants were eventually eliminated for
consideration in Round One or Round Two rulemakings; 254 were
eliminated because they were not detected in any or in fewer than one
percent of the sewage sludge samples surveyed in the NSSS, and others
were dropped because of a lack of sufficient information on their
toxicity and environmental properties. In particular, 44 of the 411
pollutants, though detected at a frequency of greater than one percent,
were dropped from further consideration because of lack of data on
human health benchmarks and/or environmental properties. For a more
detailed description of the process for Round One and Two, see USEPA,
2002c.
For the current review, EPA again started with the 411 pollutants
initially identified for Round One consideration; As mentioned above,
254 of these pollutants were detected at a frequency rate of less than
one percent in the 1988-89 NSSS and therefore were dropped from further
consideration in both the Round One and Round Two rulemakings. Because
the low detection rates for these 254 pollutants could have been due to
the limits of the analytical and sampling methodology employed in 1988-
89, EPA included these pollutants in the current review for potential
addition to the Part 503 Standards. A literature search was performed
on these pollutants to identify (1) human health benchmarks, (2)
environmental properties, and (3) their presence or concentrations in
sewage sludge.
As previously mentioned, 44 of the 411 pollutants considered in the
Round One and Round Two rulemaking processes were detected at a
frequency of greater than one percent, but were dropped from further
consideration because of lack of data on human toxicity and/or
environmental properties. EPA has preliminarily determined that 23 of
the 44 are either non-toxic or non-persistent in the environment, but
is continuing to evaluate them.
Next, EPA conducted a literature search of publicly available
information to identify information on pollutants in sewage sludge
since 1990, including information on pollutants that were not among the
411 originally identified pollutants. EPA has collected 459 scientific
papers from national and international government entities,
universities, non-profit and other private entities for the time period
of 1990-2002, the date of the last NSSS to the present (USEPA, 2002d).
Of these 459 papers, 216 papers concern either the Round One or Round
Two pollutants only. The balance of these papers, 243, concern or
potentially concern pollutants that were not the subjects of Rounds One
or Two. Subsequently, these 243 papers were reviewed to verify which of
the papers do in fact concern pollutants which were not the subjects of
Rounds One and Two. In addition, these papers were reviewed for human
health benchmarks, environmental properties, and presence or
concentrations of these pollutants in sewage sludge.
EPA also collected information from EPA databases and several other
existing databases with respect to human health benchmarks, and found
170 pollutants with some human health benchmarks among these databases
(USEPA, 2002e). These databases include: EPA's Integrated Risk
Information System, EPA's Superfund Technical Support Center
Provisional Toxicity Values, EPA Health Assessment Documents,
California Environmental Protection Agency Chronic Inhalation Reference
Exposure Levels and Cancer Potency Factors, Agency for Toxic Substances
and Disease Registry Minimal Risk Levels, and Health Effects Assessment
Summary Tables.
The next step in this process was to ascertain whether analytical
methods exist for detecting and quantifying each of these pollutants in
sewage sludge (USEPA, 2002f, USEPA, 2002g, USEPA, 2002h). Although the
accuracy, precision, and limits of detection of analytical
methodologies for chemical pollutants in the sewage sludge matrix have
significantly improved since the 1988-89 NSSS, there are still many
pollutants for which no validated analytical methods exist.
In summary, EPA evaluated publicly available information with
respect to presence in sewage sludge, toxicity (including human health
benchmarks), persistence, mobility and potential for exposure for the
pollutants contained in each of the four groups of pollutants described
above: (1) The 254 pollutants with a low frequency of detection in the
1988-89 NSSS, (2) the 44 toxic pollutants that were detected at a
frequency of greater than one percent in the 1988-1989 NSSS, but that
had insufficient information to be able to perform subsequent
evaluation, (3) the pollutants that were not the subject of Rounds One
or Two but are covered in the 243 papers that turned up in the
literature search, and (4) the 170 pollutants for which some health
benchmark exists in the literature. These four groups of pollutants as
described above were compared to eliminate any duplicates. Finally, EPA
evaluated all of these pollutants to determine whether there are
sufficiently accurate and precise analytical methodologies with
adequate detection limits for these pollutants in the sewage sludge
matrix. These results are available in detail in the docket for this
notice (USEPA, 2003b).
These preliminary results will be further analyzed, leading to a
risk-based screening analysis. The criteria for determining whether to
proceed to a screening analysis for any pollutant are whether there
are: (1) Adequate and reliable data regarding concentration of the
pollutant in sewage sludge, (2) a current human health benchmark, (3)
adequate information on environmental properties, such as persistence
and mobility, and (4) an appropriate analytical method for the
pollutant. In evaluating item 2 above, EPA will focus initially on
chemicals for which there is a current peer-reviewed human health
benchmark developed by EPA. EPA will next determine the adequacy of the
available environmental properties data for use in the risk-based
screening analysis.
The results of this screening analysis will serve as a basis for
determining whether additional toxic pollutants should be considered
for regulation in sewage sludge under section 405(d) of the Clean Water
Act. As noted above, EPA has not yet identified any additional
pollutants for regulation. Inclusion in the results presented today
does not mean that a pollutant has been determined to be present in
sewage sludge in concentrations that may adversely affect human health
or the environment. Some, or even all, of these chemicals that have
been detected in sewage sludge may only be present infrequently or in
trace amounts, and may not present a risk of adverse effects to human
health or the environment. Also, the properties or degree of toxicity
of such chemicals may make their presence, even in higher amounts, of
little risk to human health or the environment. As noted above, the NRC
concluded that while there are significant data gaps, there is
currently no documented scientific evidence that the existing Part 503
regulations have failed to protect public health. These results,
however, are an important step forward in that they identify chemicals
for which sufficient new information exists to proceed to a risk-based
screening analysis, as well as data gaps that must be filled for other
chemicals before such a screening analysis can be conducted.
[[Page 17395]]
EPA expects to complete its risk-based screening analysis of
chemicals for which adequate information is currently available by
January 2004. At that time EPA will identify those pollutants, if any,
for which EPA plans to initiate a rulemaking under section 405(d). EPA
requests comment on the methodology and results to date of its review
under section 405(d)(2)(C) of the CWA. EPA also requests information
that may help to fill data gaps for those chemicals for which
sufficient information is not yet available to conduct a risk-based
screening analysis.
X. What Are the Primary Issues for Public Comment?
While the EPA is requesting comments on all of the information
discussed in this Notice, the Agency hopes that the public comment will
also focus specifically on the following aspects of this Notice:
1. The Agency's preliminary strategy for responding to the NRC
Recommendations, given that the Agency's biosolids program does not
have sufficient resources to implement all of the recommendations.
2. EPA requests comment on its review under section 405(d)(2)(C) of
the CWA. EPA also requests information that may help to fill data gaps
for those chemicals for which sufficient information is not yet
available to conduct a risk-based screening analysis.
3. 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, such
as the Centers for Disease Control and Prevention.
4. The Agency's plan to begin designing a survey using information
obtained from published pollutant occurrence and effects data, State
occurrence data bases, and input received during the public comment
period.
XI. References
NRC, 1996. Use of Reclaimed Water and Sludge in Food Crop
Production. The National Academies Press. Washington, DC. Available
online at http://www.nap.edu/catalog/5175.html NRC, 2002.
Biosolids Applied to Land; Advancing Standards and Practices, National
Research Council of the National Academies. The National Academies Press.
Available online at http://search.nap.edu/books/0309084865/html.
University of Arizona, National Science Foundation, Water Quality
Center, within the Environmental Research Laboratory. Several studies
ongoing. Ian L. Pepper, Director. Tuscon, Arizona.
USEPA, 1994. A Plain English Guide to the EPA Part 503 Biosolids
Rule. 190 pages. Office of Water, Office of Wastewater Management.
Available online at: http://www.epa.gov/owm/mtb/biosolids/503pe/index.htm.
USEPA, 1996. Technical Support Document for the Round Two Sewage
Sludge Pollutants. EPA-822-R-96-003. Office of Water. Washington, DC.
August, 1996.
USEPA, 2002a. Compilation of National Research Council (NRC)
Recommendations on Biosolids and EPA Responses and Activities. 9 pages.
Office of Water, Office of Science and Technology. Washington, DC.
USEPA, 2002b. Guidelines for Ensuring and Maximizing the Quality,
Objectivity, Utility, and Integrity of Information Disseminated by the
Environmental Protection Agency. EPA 260R-02-008. Office of
Environmental Information. Washington, DC. October 2002. Available
online at http://www.epa.gov/oei/qualityguidelines.
USEPA, 2002c. Screening History for the Part 503 Rounds One and Two
Proposal. 4 pages. Office of Water, Office of Science and Technology.
Washington, DC.
USEPA, 2002d. Literature Search of Publicly Available Information
to Identify Information on Pollutants in Sewage Sludge Since 1990. 48
pages. Office of Water, Office of Science and Technology. Washington,
DC.
USEPA, 2002e. Human Health Benchmarks for Potential Constituents in
Biosolids. 11 pages. Office of Water, Office of Science and Technology.
Washington, DC.
USEPA, 2002f. List of Analytes from the 1989 National Sewage Sludge
Survey Found in Less than 1% of the Samples. 7 pages. Office of Water,
Office of Science and Technology. Washington, DC.
USEPA, 2002g. Summary of Analytes from the 1989 National Sewage
Sludge Survey. 12 pages. Office of Water, Office of Science and
Technology. Washington, DC.
USEPA, 2002h. Potential Analytes. 5 pages. Office of Water, Office
of Science and Technology. Washington, DC.
USEPA, 2003a. In press. Contemporary Perspectives on Infectious
Disease Agents In Sewage Sludge and Manure. Compost Science &
Utilization/The JG Press, Inc.
USEPA, 2003b. Candidate Pollutants for Ongoing Sewage Sludge
Evaluation. 15 pages. Office of Water, Office of Science and
Technology. Washington, DC.
WERF, 2003. Dynamic Model to Assess Microbial Health Risks
Associated with Beneficial Uses of Biosolids. Cooperative Agreement No.
CR-825237. Alexandria, VA.
Dated: April 2, 2003.
G. Tracy Mehan III,
Assistant Administrator, Office of Water.
[FR Doc. 03-8654 Filed 4-8-03; 8:45 am]
BILLING CODE 6560-50-P