%	United States
Environmental Protection
\*^l # % Agency
Office of Water
EPA 822-F-20-001
April 2020
Withdrawal of Federally Promulgated Human Health
Water Quality Criteria in Washington State
On May 10, 2019, EPA approved a suite of Clean
Water Act (CWA) human health criteria (HHC) that
were developed by the state of Washington through
a lengthy stakeholder process. EPA had originally
disapproved many of those criteria. However, upon
reconsideration, the agency found the state's
standards to be based on sound science and
protective of the state's designated uses. Because
EPA approved the state of Washington's criteria, on
April 16, 2020 the agency finalized its withdrawal of
federally-promulgated HHC for waters under the
state of Washington's jurisdiction. As a result, the
state of Washington's criteria will be effective for
CWA purposes. EPA is respectful of the state's
primary role in determining its water quality
standards and its discretion in making resource- and
risk-management decisions related to protecting the
health of its citizens. This action restores the balance
mandated by the CWA, in which the states lead the
standards-setting process.
Federal HHC will remain in place for Washington
State for three pollutants: methylmercury, bis (2-
chloro-l-methylethyl) ether, and arsenic. The state
of Washington did not submit criteria for
methylmercury and bis (2-chloro-l-methylethyl)
ether. Therefore, the federally promulgated criteria
are the only criteria in effect for those pollutants in
the state. Additionally, on May 10, 2019, EPA
reaffirmed its November 2016 disapproval of the
two criteria that the state of Washington submitted
for arsenic (one for waters designated for public
water supply plus fishing and shellfish harvesting,
and another for waters designated only for fishing
and shellfish harvesting). The federal arsenic criteria
for the state of Washington will remain in place.
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After partially disapproving certain HHC that the
state of Washington submitted to EPA in August
2016, on November 28, 2016, EPA promulgated a
final rule titled "Revision of Certain Federal Water
Quality Criteria Applicable to Washington" at 40 CFR
131.45.1 In February 2017, EPA received a petition
from several organizations to reconsider the
Agency's 2016 partial disapproval.
In August 2018, EPA decided to reconsider its partial
disapproval of the state of Washington's HHC and on
May 10, 2019, EPA approved a suite of HHC that
were submitted by the state in 2016. As a result of
this approval action, on July 23, 2019, EPA issued a
proposed rule to withdraw certain federal HHC for
waters under the state of Washington's
jurisdiction. EPA provided 60 days for public
comment on its proposal and received more than
5,000 comments. The agency's final rule reflects
comments received on the proposal.
1 Revision of Certain Water Quality Standards Applicable to
Washington, 81 FR 85417 (November 28, 2016).