NC0023736_Permit (Modification)_19970627

State of North Carolina
Department of Environment,
Health and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Jonathan B. Howes, Secretary
A. Preston Howard, Jr., P.E., Director
June 27,1997
Mr. Monte Wall
City of Lenoir
P.O. Box 958
Lenoir, North Carolina 28645
Dear Mr. Wall:
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Subject: NPDES Permit Modification
NPDES Permit No. NC0023736
Lenoir - Gunpowder Creek WWTP
Caldwell County
The Division received your request for a reduction in effluent monitoring at the subject facility
on May 9, 1997. Accordingly, we are forwarding herewith this modification to the subject permit.
Please find enclosed the amended Special Conditions page which should be inserted into your
permit. The old page should be discarded. All other terms and conditions contained in the original
permit remain unchanged and in full effect. The permit modifications are issued pursuant to the
requirements of North Carolina General Statutes 143-215.1 and the Memorandum of Agreement between
North Carolina and the U. S. Environmental Protection Agency.
If any parts, measurement frequencies or sampling requirements contained in this permit
modification are unacceptable to you, you have the right to an adjudicatory hearing upon written
request within thirty (30) days following receipt of this letter. This request must be in the form of a
written petition, conforming to Chapter 150B of the North Carolina General Statutes, and filed with
the Office of Administrative Hearings, Post Office Drawer 27447, Raleigh, North Carolina 27611-
7447. Unless such demand is made, this decision shall be final and binding.
If you have any questions concerning this permit modification, please contact Charles Weaver
at telephone number [phone], extension 511.
cc. Central Files
Asheville Regional Office
Permits and Engineering Unit
Facility Assessment Unit
Aquatic Survey & Toxicology Unit
Sincerely,
ffivA. Preston Howard, Jr., P.E.
P.O. Box 29535, Raleigh, North Carolina 27626-0535 Telephone [phone] FAX [phone]
An Equal Opportunity Affirmative Action Employer 50% recycled / 10% post -consumer paper

Part III
Permit No. NC0023736
G. INSTREAM MONITORING REQUIREMENTS
Parameter Frequency
Dissolved Oxygen) Weekly
Temperature) Weekly
Conductivity) Weekly
Fecal Coliforml Weekly
pH2 Weekly
Total Phosphorus2 Monthly
Total Nitrogen2 Monthly
Chlorophyll a2 Monthly
Sample Type Location
Grab U, D1, D2, D3
Grab U, D1, D2, D3
Grab U, D1, D2, D3
Grab U, D1, D2, D3
Grab U, D1, D2, D3
Grab U, D1, D2, D3
Grab U, D1, D2, D3
Grab U. D1. D2, D3
Locations: U - at least 100 feet upstream;
D1 - approximately 2000 feet below the outfall3
D2 - Gunpowder Creek before start of the Old Millpond or at NCSR 1002
D3 - at NCSR 1107 in the pooled area of the Old Millpond
1: Sampling frequency increases to 3/week at all sites during June, July August & September.
2: Monitoring required only during May, June, July, August & September.
3: Monitoring at this location will be dropped if the facility chooses to monitor stream flow either above or
below the Old Millpond Dam by January 1,1996.
H . CHRONIC TOXICITY PASS/FAIL
PERMIT LIMIT (QUARTERLY)
The effluent discharge shall at no time exhibit chronic toxicity using test procedures outlined in the "North
Carolina Ceriodaphnia Chronic Effluent Bioassay Procedure," Revised November 1995, or subsequent versions.
The effluent concentration at which there may be no observable inhibition of reproduction or significant
mortality is 38% (defined as treatment two in the procedure document). The permit holder shall perform
quarterly monitoring using this procedure to establish compliance with the permit condition. The first test will
be performed after thirty days from the effective date of this permit during the months of March, June,
September and December. Effluent sampling for this testing shall be performed at the NPDES permitted final
effluent discharge below all treatment prolcesses.
All toxicity testing results required as part of this permit condition will be entered on the Effluent Discharge
Monitoring Form (MR-1) for the month in which it was performed, using the parameter code TGP3B.
Additionally, DWQ Form AT-1 (original) is to be sent to the following address:
I
Attention: Environmental Sciences Branch
North Carolina Division of Water Quality
4401 Reedy Creek Road
Raleigh, North C rolina 27607
Test data shall be complete and accurate and include all supporting chemical/physical measurements
performed in association with the toxicity tests, as well as all dose/response data. Total residual chlorine of
the effluent toxicity sample must be measured and reported if chlorine is employed for disinfection of the waste
stream.