NC0021491_Permit Modification_20010427

`OR\ wpT �RQ Michael F. Easley
y Governor
> William G. Ross, Jr., Secretary
Y North Carolina Department of Environment and Natural Resources
Kerr T. Stevens, Director
Division of Water Quality
April 27, 2001
Mr. Terry Bralley, Manager
Town of Mocksville
171 Clement Street
Mocksville, North Carolina 27028
Subject: Permit Modification --
NPDES Permit NCO021491
Dutchman's Creek WWTP
Davie County
Dear Mr. Bralley:
The Division of Water Quality (the Division) has recently become aware of an error in your
NPDES permit, renewed in January 2001, for the Dutchman Creek Wastewater Treatment Plant. Your
Operator in Responsible Charge (ORC) recently contacted the Division regarding the need to monitor
"influent" Biochemical Oxygen Demand (BODs ) and Total Suspended Solids (TSS).
All Publicly Owned Treatment Works (POTW) are required to monitoring both "influent" and
"effluent" waste streams for BODs and TSS. Please except the Division's apologies for this omission.
This letter transmits a revised Effluent Limitations and Monitoring Requirements page. Please insert this
page into your existing permit and discard the old page. Correcting this error constitutes a "minor
modification" and will not require public notice.
If any parts, measurement frequencies, or sampling requirements contained in this permit
modification are unacceptable, you have the right to an adjudicatory hearing upon written request within
thirty (30) days after receiving this letter. Your 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, 6714 Mail Service Center, Raleigh, North Carolina 27699-6714. Unless such a demand is made,
this permit modification shall be final and binding.
If you have questions, or if we can be of further service, please call Joe Corporon at (919) 733-
5083, extension 597.
Respectfully,
err T�'
Director
Enclosure: NPDES Permit NCO021491 —Effluent Limitation and Monitoring Requirements page
cc: Central Files
NPDES Unit
Winston-Salem reoional Office, Water Quality Section
Pretreatment Unit Files
Point Source Compliance and Enforcement Unit
Technical Assistance and Certification Unit A
AV*
NCDENR
N. C. Division of Water Quality 1617 Mail Service Center Raleigh, NC 27699-1617 [phone] Customer Service
1 800 623-7748

Permit. NCO021491
A. (1.) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS
During the period beginning on the effective date of the permit and lasting until expiration, the Permittee is authorized to
discharge from outfall 001. Such discharges shall be limited and monitored by the Permittee as specified below:
EFFLUENT; .
CHARACTERISTICS
LIMITS
' MONITORINGREQUIREMENTS
t'
r -
Monthly
` Average
Weekly
Average
Daily .
Maximum
Measurement
Frequency -
:Sample -
Type :
- Sample Location
= -
Flow
0.68 MGD
Continuous
Recording
Influent or Effluent
BOD, 5 day, 20 °C2
24.0 mg/I
36.0 mg/I
Weekly
Composite
Influent and Effluent
Total Suspended Residue2
30.0 mg/I
45.0 mg/1
- Weekly
Composite
Influent and Effluent
NH3 as N
14.0 mg/I
Weekly
Composite
Effluent
Dissolved Oxygen3
Weekly
Grab
Effluent,
Upstream and Downstream
Fecal Coliform
(geometric mean
200 / 100 ml
400 ! 100 ml
Weekly
Grab
Effluent
Total Residual Chlorine
2/Week
Grab
Effluent
Temperature
Daily
Grab
Effluent,
Upstream and Downstream
Total Nitrogen
(NO2 + NO3 + TKN)
Weekly
Composite
Effluent
Total Phosphorus
Weekly
Composite
Effluent
Chronic Toxicity4
Quarterly
Composite
Effluent
Cadmium
Monthly
Composite
Effluent
Chromium
Monthly
Composite
Effluent
Copper
Monthly
Composite
Effluent
Nickel
Monthly
Composite
Effluent
Lead
Monthly
Composite
Effluent
Zinc
Monthly
Composite
Effluent
Cyanide
76.0 I
2/Month
Grab
Effluent
Silver
Monthly
Composite
Effluent
H5
Weekly
Grab
Effluent
Notes:
1. Upstream = approximately 100 feet upstream from the outfall. Downstream = approximately 0.5 miles downstream from
the outfall. Upstream and downstream samples shall be grab samples collected 3/week during June, July, August, and
September and once per week during the rest of the year. As a participant in the Yadkin Pee -Dee River Basin Association,
the subject facility is not responsible for conducting the instream monitoring requirements as stated above. Should your
membership in the agreement be terminated, you shall notify the Division immediately and the instream monitoring
requirements specified in your permit will be automatically reinstated.
2. The monthly average effluent BOD5 and Total Suspended Residue concentrations shall not exceed 15 percent of the
respective influent value (85% removal).
3. The daily average dissolved oxygen effluent concentration shall not be less than 5.0 mg/l.
4. Chronic Toxicity (Ceriodaphnia) at 7%: January, April, July & October (see condition A. (2)).
5. The pH shall not be less than 6.0 standard units nor greater than 9.0 standard units.
There shall be no discharge of floating solids or visible foam in other than trace amounts.