NC0074268_technical Correction_20110425

AVA
NCDENR
North Carolina Department of Environment and Natural Resources
Division of Water Quality
Beverly Eaves Perdue Coleen H. Sullins Dee Freeman
Governor Director Secretary
April 25, 2011
Larry Cummings, Division Manager of Wastewater Treatment
City of Gastonia
P.O. Box 1748
Gastonia, North Carolina 28053
Subject: Correction to Permit NC0074268
Crowders Creek WWTP
Gaston County
Dear Mr. Cummings:
The Division of Water Quality (Division) has recently become aware of a typographical error made in
your recently -renewed NPDES permit referenced above. The effluent limitations table in A (1)
incorrectly specified a quarterly monitoring frequency for mercury. As stated in the cover letter, this
monitoring frequency should be monthly. A revision table is attached for your records.
As stated in the cover letter, you may request a minor modification to change the monitoring frequency
for mercury to quarterly, following 12 consecutive months of sampling results below 12 ng/L. We
apologize for any misunderstandings.
If you have questions, or if we can be of further assistance, please contact Mr. Gil Vinzani at
[[e-mail]] or call [phone].
Sinc�rely,
m Belnick, Supervisor
Complex Permitting Unit
Cc: Mooresville Regional Office, Surface Water Protection Section
NPDES Unit Files
Central Files
1617 Main Service renter, Raleigh, North Carolina 27699-1617
Location: 512 N. Salisbury St. Raleigh, North Carolina 27604
Phone: [phone] FAX: [phone] Customer Service: 1-877-623-6748
Internet: www.ncwaterquality.org
An Equal Opportunity \ Affirmative Action Employer
NorthCarolina
Naturally

Permit NC0074268
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
•
-CIIIIIIA= aJ a1.lct.iiicu ucivvv.
EFFLUENT CHARACTERISTICS
a"" LIMITS
=(MONITORING
REQUIREMENTS.
Monthly
Average
Weekly
Average
Daiay
Max
Measurement F"
Frequency ;
Sample
Type
Sample,
Location;:"
Flow
6.0 MGD
Continuous
Recording
I or E
2
BOD, 5-day, 20°C
13.0 mg/L
g
19.5 mg/L
g
Daily
Composite
I and E
Total Suspended Solids L
30.0 ring/45.0
mg/L
Daily
Composite
I and E
NH3 as N
(April 1 - October 31)
2.0 mg/L
6.0 mg/L
Daily
Composite
E
NH3 as N
(November 1 - March 31)
10.0 mg/L
30.0 mg/L
Daily
Composite
E
Dissolved Oxygen 3
Daily
Grab
E, U, D
Fecal Coliform
(geometric mean) 4
200/100 ml
400/100
ml
Daily
Grab
E, U, D
Temperature
Daily
Grab
E, U, D
pH
B
Between 6.0 and 9.0 s. u.
Daily
Grab
E
Total Residual Chlorine 5
28
pg/L
Daily
Grab
E
Conductivity
3/week
Grab
E, U, D
Total Nitrogen (NO2+ NO3 + TKN)
(April 1 - October 31)
6.0 mg/L
Weekly
Composite
E
Total Nitrogen (NO2+ NO3 + TKN)
(November 1 - March 31)
Weekly
Composite
E
Total Phosphorus
1.0 mg/L
Weekly
Composite
E
Chronic Toxicity b
Quarterly
Composite
- E
Bis(2-ethylhexyl)phthalate
Quarterly
Grab
E
7
Total Mercury
0.012 pg/L
0.036
pg/L
MonthlyGrab
E
Total Nickel
Quarterly
Composite
E
Total Copper
Quarterly
Composite
E
Total Zinc
Quarterly
Composite
E
Total Silver
Quarterly
Composite
E
Annual Pollutant Scan 8
Annual
Composite
E
Notes:
1. U= Upstream at NCSR 1108. D= Downstream at a) NCSR 2424 and b) NCSR 564. Instream monitoring
shall be grab samples taken 3/week (June -September) and 1/week (October -May).
2. The monthly average effluent BOD5 and Total Suspended Solids concentrations shall not exceed 15% of
the respective influent value (85% removal).
3. The daily average dissolved oxygen effluent concentration shall not be less than 6.0 mg/L.
4. lnstream fecal coliform monitoring is required 3/week during summer months only (June -September).
Downstream samples need only be taken at NCSR 2424.
5. The Division shall consider all effluent TRC values reported below 50 pg/I to be in compliance with the
permit. However, the Permittee shall continue to record and submit all values reported by a North Carolina
certified laboratory (including field certified), even if these values fall below 50 pg/I.
6. Chronic Toxicity (Ceriodaphnia), P/F at 41 % with testing in March, June, September and December (see
condition A (2)).
7. The permittee may request a minor modification to change the monitoring frequency to quarterly, following
12 consecutive months with values below 0.012 pg/L. EPA Method 1631 shall be used in all analyses.
8. See condition A (3).
- -There shall be no discharge of -floating solids or foam in other than trace amounts.
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