United States               nft.
                       Environmental Protection  Offlce of Water
                                                                           March  2012
                        Biosolids Biennial Reviews
Section 405(d)(2)(C) of the Clean Water Act
(CWA) requires EPA to review the sewage
sludge regulations every two years. The purpose
of such reviews is to identify, where possible,
additional toxic pollutants and promulgate
regulations for those pollutants consistent with
the requirements set forth in the Act. In fulfilling
this commitment for Biennial Review Cycles
2005, 2007 and 2009, EPA collected and
conducted a review of publicly available
information. The Agency searched known
databases and the published literature designed
to capture available information on occurrence,
fate and transport and human health or
ecological effects, as well as other relevant
information for pollutants that may occur in U.S.
sewage sludge. The available exposure or
toxicity data are not sufficient at this time for
many of the pollutants using current biosolids
modeling tools. We will continue this work
subject to availability of resources and overall
program priorities. At this time, EPA has not
identified additional toxic pollutants for
regulation under  Section 405(d)(2)(C) of the

Standards for the Use or Disposal of Sewage
Under Section 405(d), EPA establishes numeric
limits and management practices that protect
public health and the environment from the
reasonably anticipated adverse effects of
chemical and microbial pollutants in sewage
sludge. On February 19, 1993, EPA promulgated
the CFR 40 Part 503 Standards for the Use or
Disposal  of Sewage Sludge, resulting in numeric
standards for ten metals and operational
standards for microbial organisms. The  1993
rule established requirements for the final use or
disposal of sewage sludge when it is: (1) applied
to land as a fertilizer or soil amendment; (2)
placed in a surface disposal site, including
sewage sludge-only landfills; or (3) incinerated.
These requirements 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.

Since promulgation of 40 CFR 503, there have
been three subsequent rounds of review:  (1) the
Agency's decision in 2002 that regulation of
dioxin and dioxin-like compounds disposed via
incineration or land-filling was not needed for
adequate protection of public health and the
environment, (2) the Agency's decision in 2003
that regulation of dioxin and dioxin-like
compounds in land-applied sewage sludge was
not needed for adequate protection of public
health and the environment (68 FR 61084), and
(3) a review that resulted in the ongoing analysis
of nine pollutants and molybdenum; by late
2012, EPA expects to complete evaluation of
these pollutants using available data and the
recently released Targeted National Sewage
Sludge Survey results prior to taking action or
determining whether to propose regulating any
of these pollutants under section 405(d) of the

Current Biennial Review
In conducting the biennial review for 2009, EPA
collected publicly available information on
pollutants. The purpose of reviewing
information on pollutants, or potential
pollutants, is to assess the availability and
sufficiency of the data to conduct exposure and
hazard assessments.  Exposure and hazard
assessments, where sufficient data exist, allow
the Agency to determine the potential for harm
to public health or the environment following
use or disposal of biosolids.  Some of the
information generally needed to conduct
exposure and hazard assessment includes the
ability to detect and quantify a given pollutant in
sewage sludge, concentration data in sewage
sludge, fate and transport data for pollutants that
may be present in sewage sludge, chemical and

physical properties and toxicity to human and
ecological receptors. The Agency assessed
whether data for pollutants were sufficient to
conduct human health and ecological exposure
and hazard assessments.
Results of the Literature Search
The Agency's search of peer-reviewed literature
identified information for 49 pollutants from the
potential universe of pollutants for which some
data were available. Some pollutants (e.g.,
triclosan and azithromycin) have been reported
in previous biennial reviews. EPA revisits
previously evaluated pollutants when literature
searches of bibliographic databases reveal newer
data. Even though critical pieces of data (e.g.,
human health toxicity and concentration data)
were available for 14 pollutants, critical
information gaps remain (e.g., ecological effects
endpoints, aerobic biodegradation in soil and
water, anaerobic biodegradation in sediment,
bioconcentration, and biotransfer factors).
Therefore, at this time EPA has not identified
any additional toxic pollutants for regulation
under Section 405(d)(2)(C) of the CWA.
The Agency will continue to assess the
availability of sufficient information for these 49
pollutants and other pollutants identified during
the biennial review activities pursuant to section
405(d)(2)(C) of the CWA. As its first priority,
EPA has begun the evaluation of 145 pollutants
identified in the recent Targeted National
Sewage Sludge Survey:
upload/2009_0 l_15_biosolids_tnsss-tech.pdf
For More Information
To get more information about the Biosolids
Program, please call Rick Stevens at (202) 566-
1135 or send an email to stevens.rick@epa.gov.