NC0046418_Fact Sheet_20230815

NCDEQ / DWR / NPDES
EXPEDITED FACT SHEET - NPDES PERMIT RENEWAL
NPDES Permit NCO046418
Catherine Shadwell, Compliance & Expedited Permitting Unit / 919-707-3613 Aug 2023
FACILITY INFORMATION
Applicant/Facility Name
Wilkes County Schools (Thomas J Spicer, ORC)
Mountain View Elementary School WWTP
Applicant Address
613 Cherry St North Wilkesboro, NC 28659
Facility Physical Address
5464 Mountain View Rd Hays, NC 28635
Permitted Flow (MGD)
0.01 MGD
Type of Waste
100% Domestic, < 1 MGD
Facility Class
WW-1
County
Wilkes
Permit Status
Renewal
Regional Office
WSRO
STREAM CHARACTERISTICS
Receiving Stream
UT to Mulberry Creek
Stream
Classification
C
Stream Segment
12-42
Outfall Lat.
360 14' 53" N
7Q10 - Summer (cfs)
0
Outfall Long.
810 0702" W
7Q10 - Winter (cfs)
0
Drainage basin
Yadkin -Pee Dee
30Q2 (cfs)
0
Subbasin
03-07-01
Average Flow (cfs)
0.075
HUC
030401010405
IWC (%)
100% (summer) / 100%
(winter)
303(d) List
Not listed.
BASIC INFO FOR EXPEDITED PERMIT RENEWAL
Does permit need Daily Max NH3 limits?
Already present in permit
Does permit need TRC limits/footnote?
Already present in permit
(Does permit have toxicity testing?
No
Does permit have any Special Conditions?
Yes, nutrient reopener for high rock lake
Does permit have instream monitoring?
No
New expiration date:
Sep 30, 2028
Facility Summary
Wilkes County Schools operates a small private WWTP for Mountain View Elementary School. The permit
was originally issued in 1981. The facility houses the following components.
0 Septic Tank
0 Single -siphon dosing tank
• Surface sandfilter
• Calcium hypochlorite disinfection
• Sodium sulfite dehlorination
• Pumping station
• 9,270 linear feed of force main
• Concrete vault
Renewal Summary
This renewal contains the following changes:
• Added the facility grade to Section A. (1.).
Fact Sheet for Permit Renewal
Aug 2023 - NPDES Permit NCO046418 - Page 1

• Updated Section A. (2) to reflect current federal requirements for Electronic Reporting of
Discharge Monitoring Reports.
• Updated ammonia limits as required by streamflow characteristics.
• Updated total residual chlorine limit as required by streamflow characteristics.
• Updated Outfall map
Compliance History
Most recent NOV was issued in 2015.
Most recent inspection (Feb 2020) found facility to be in compliance.
Comments on Draft Permit
Fact Sheet for Permit Renewal
Aug 2023 - NPDES Permit NC0046418 - Page 2

IWC Calculations
Facility: Mountain View Elementary School WWTP
Permit No.: NC0046418
Prepared By: Catherine Shadwell
Enter Design Flow (MGD): 0.01
Enter s7Q10 (cfs): 0
Enter w7Q10 (cfs): 0
Total Residual Chlorine (TRC)
Ammonia (Summer)
Daily Maximum Limit (ug/1)
Monthly Average Limit (mg NH3-N/1)
Design Permitted
Design
Permitted
s7Q10 (CFS) 0 0
s7Q10 (CFS)
0
0
DESIGN FLOW (MGD) 0.01 0.2
DESIGN FLOW (MGD)
0.01 €
0.2
DESIGN FLOW (CFS) 0.0155 0.31
DESIGN FLOW (CFS)
0.0155
0.31
STREAM STD (UG/L) 17.0 17
STREAM STD (MG/L)
1.0
1
Upstream Bkgd (ug/1) 0 0
Upstream Bkgd (mg/1)
0.22
0.22
IWC (%) 100.00 100.00
IWC (%)
100.00
100
Allowable Conc. (ug/1) 17 17
Allowable Conc. (mg/1)
1.0
1.0
< 1 MGD Policy Applies
Ammonia (Winter)
Monthly Average Limit (mg NH3-N/1)
Design Permitted
Design
Permitted
Fecal Coliform
w7Q10 (CFS)
0
0
Monthly Average Limit: 200/100m1 € 200/100m1
DESIGN FLOW (MGD)
0.01
0.2
(If DF >331; Monitor)
DESIGN FLOW (CFS)
0.0155
0.31
(If DF<331; Limit)
STREAM STD (MG/L)
1.8
1.8
Dilution Factor (DF) 1.00 1.00
Upstream Bkgd (mg/1)
0.22
0.22
IWC (%)
100.00
100.00
Allowable Conc. (mg/1)
1.8
1.8
Total Residual Chlorine
1. Cap Daily Max limit at 28 ug/I to protect for acute toxicity
Ammonia (as NH3-N)
1. If Allowable Conc > 35 mg/l, Monitor Only
2. Monthly Avg limit x 3 = Weekly Avg limit (Municipals)
3. Monthly Avg limit x 5 = Daily Max limit (Non-Munis)
If the allowable ammonia concentration is > 35 mg/L, no limit shall be imposed
By Policy dischargers < 1 MGD get limits no lower than 2 & 4 due to BAT
* From 2B .0404(c) - Winter Limits can be no less stringent than
2 times the summer limits
Fecal Coliform
1. Monthly Avg limit x 2 = 400/100 ml = Weekly Avg limit (Municipals) = Daily Max limit (Non -Muni)