NC0040797_Monitoring (Report)_20230811

ROY COOPER
Governor
ELIZABETH S. BISER
Secretary
RICHARD E. ROGERS, JR.
Director
Shawn Pennell, Public Utilities Director
City of Hickory
Post Office Box 398
Hickory, NC 28603-0398
SUBJECT: Toxicity Test Results
Henry Fork WWTP
NPDES Permit No. NCO040797
Catawba County
Dear Mr. Pennell:
NORTH CAROLINA
Environmental Quality
August 11, 2023
Enclosed is a copy of the toxicity test results relative to the samples collected at the subject facility on August 1 and 3,
2023, by Mr. Wes Bell of this Office. Effluent samples were collected for use in a chronic Ceriodaphnia dubia pass -fail
toxicity test. The test Passed utilizing these samples. Please inform the facility's Operator -in -Responsible Charge (ORC) of
our findings by forwarding the enclosed report.
Should you have any questions concerning this report, please do not hesitate to contact Mr. Bell at [phone] or at
wes.bell(kdeq.nc. gov.
Enclosure: Toxicity Test Results
Cc: DWR Laserfiche
Sincerely,
EA
DocuSigned by:
wNNuft
F161 F669A2D84A3...
Andrew H. Pitner, P.G.
Regional Supervisor
Water Quality Regional Operations Section
Mooresville Regional Office
Division of Water Resources, NCDEQ
D North Carolina Department of Environmental Quality I Division of Water Resources
Mooresville Regional Office 1 610 East Center Avenue, Suite 301 1 Mooresville, North Carolina 28115
704.663.1699

DocuSign Envelope ID: A789DCA4-0196-4B41-AB9B-8F6AC2100B6E
pEQ�� DWR
o:F��omo�oor f�rtrdl�ne�m�ao.��� /'� Division of Wt., Resources
August 11, 2023
MEMORANDUM
To: Andrew Pitner
Water Quality Regional Operations, MRO
Through: Cindy A. Moore
Supervisor, Aquatic Toxicology Branch (ATB)
From: Madison E. Myers
Environmental Specialist ll, Aquatic Toxicology Branch (ATB)
Subject: Whole effluent toxicity test results
Henry Fork WWTP
NPDES Permit # NCO040797/001
Catawba County
The aquatic toxicity test using flow -proportional composite samples of effluent discharged from
the Henry Fork WWTP has been completed. Henry Fork WWTP has a permitted effluent
discharge of 9.0 million gallons per day (MGD) entering Henry Fork River (7Q10 of 27 CFS).
Whole effluent samples were collected on August 1 and August 3 by Wes Bell for use in a
chronic Ceriodaphnia dubia pass -fail toxicity test. The test passed. Toxicity test information
follows.
Test Type 3-Brood Ceriodaphnia dubia chronic pass -fail
Test Result Pass
Test Concentrations 34%
Control Survival 100%
Control Mean Reproduction 23.3 neonates
Test Treatment Survival 91.7%
Treatment Mean Reproduction
First Sample pH
First Sample Conductivity
First Sample Total Residual Chlorine
Second Sample pH
Second Sample Conductivity
Second Sample Total Residual Chlorine
26.1 neonates
6.84 SU
556 micromhos/cm
0.49 mg/L
6.65 SU
742 micromhos/cm
<0.1 mg/L
Test results for the above samples indicate that the effluent would not be predicted to have
water quality impacts. Please contact us if you have any questions or if further effluent toxicity
monitoring is desired. We may be reached at [e-mail] or
[e-mail].
Basin: Catawba
cc: Wes Bell (MRO)