High Rock Lake Chl a Letter 12.07.22

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
REGION 4
ATLANTA FEDERAL CENTER
61 FORSYTH STREET, SW
ATLANTA, GEORGIA 30303-3104
December 7, 2022
Mr. Richard E. Rogers, Jr.
Director
Division of Water Resources
NC Department of Environmental Quality
512 North Salisbury Street
1611 Mail Service Center
Raleigh, North Carolina 27699-1617
Dear Mr. Rogers:
The purpose of this letter is to approve North Carolina’s addition of a site-specific criterion for
chlorophyll a for High Rock Lake, submitted electronically to the U.S. Environmental Protection
Agency on October 25, 2022. In your letter written to Regional Administrator Daniel Blackman, you
submitted a revision which added a site-specific chlorophyll a criterion as part of the state’s Class C
designated use, to be applied specifically to High Rock Lake. In making this revision, North Carolina
has provided additional protection to the subject water.
A certification letter from the Senior Deputy Attorney General dated October 20, 2022, was included in
the submission from North Carolina and concludes that the revision was duly adopted pursuant to state
law and is valid and enforceable in the state of North Carolina. In accordance with 40 C.F.R. section
131.21(c), new and revised state and tribal water quality standards are not effective for Clean Water Act
(CWA) purposes until approved by the EPA. The EPA has concluded the revision is consistent with the
goals of section 101(a) of the CWA and the implementing regulations at 40 C.F.R. Part 131. In
accordance with section 303(c) of the CWA and 40 C.F.R. part 131, and as laid out in the enclosed
decision document, the EPA is approving this revision.
In addition to the EPA’s review pursuant to section 303(c) of the CWA, section 7(a)(2) of the
Endangered Species Act (ESA) requires federal agencies, in consultation with the U.S. Fish and Wildlife
Service (USFWS), to ensure that their actions are not likely to jeopardize the continued existence of
federally listed species or result in the destruction or adverse modification of designated critical habitat
of such species. Regarding consultation activities for section 7 of the ESA, the EPA Region 4 concluded
the revision “may affect, but was not likely to adversely affect” aquatic-dependent, ESA species present
in the area of High Rock Lake. An October 26, 2022 letter reflecting that conclusion and requesting
concurrence with the EPA’s conclusion was sent to the USFWS Asheville Ecological Services Field
Office. The USFWS concurred by letter dated November 17, 2022.
North Carolina is to be commended for their first adoption of a numeric nutrient criterion since the
implementation of their Nutrient Criteria Development Plan, last amended in 2019. North Carolina’s
Division of Water Resources (DWR) has provided significant support throughout the High Rock Lake
pilot effort, including significant staff resource support to the Scientific Advisory Council (SAC) and
Criteria Implementation Committee (CIC) as well as the traditional support provided by the state’s WQS
program staff. Chris Ventaloro, Susan Meadows, Elizabeth Kountis, Paul Wojoski, Pam Behm, Rich
Gannon, Mike Templeton, Tammy Hill, David Huffman, Nora Deamer, Elizabeth Fensin, Karen
Higgins, Bongghi Hong, Jing Lin, Mark Vanderborgh, Julie Ventaloro, Peter Johnston, Jim Hawhee,
Kelsey Rowland, Connie Brower, Steve Kroeger, Carrie Ruhlman, Jeff Manning, Brian Wrenn, and
other DWR staff attended multiple years of SAC, CIC, and internal meetings. This combined staff and
management support was essential to completing this effort.

We also very much appreciate the opportunity to have EPA staff on both the SAC and CIC and your
staff’s continued collaboration throughout. By adding the chlorophyll a criterion for High Rock Lake,
the state has completed the first lake pilot nutrient criteria development effort and more importantly,
ensured additional protections are in place for this waterbody. This updated chlorophyll a criterion
reflecting the latest conclusions on designated use protection will ensure an appropriate target is in place
for subsequent management actions to address total nitrogen and total phosphorus reductions as the state
moves towards development of its nutrient management strategy.

If you have any questions, please feel free to contact me at [phone] or have a member of your
staff contact Ms. Lauren Petter at [phone] or [e-mail].

Sincerely,

Denisse D. Diaz, Acting Director
Water Division

Enclosure