NC0043745_Wasteload Allocation_19940930

NPDES DOCUMENT SCANNING COVER SHEET
NPDES Permit:
NC0043745
Old Dock Elementary WWTP
Document Type:
Permit Issuance
Wasteload Allocation
Authorization to Construct (AtC)
Permit Modification
Complete File - Historical
Engineering Alternatives (EAA)
Return
Instream Assessment (67b)
Speculative Limits
Environmental Assessment (EA)
Document Date:
September 30, 1994
This document iia printed on reueoe paper - ignore arty
content on the reireree aside

Facility Name:
Permit Number:
Engineer:
Subbasin:
Receiving Stream:
USGS quad #:
Request Number:
Date:
Expiration date:
Old Dock Elementary - Columbus County Schools
NC0043745
Bolden
03-07-57
unnamed tributary to Gum Swamp Run
K24NE
7777
3/4/94
9/30/94
Existing WLA checked:
Staff Report:
Topo checked:
USGS Flows confirmed:
PIRF / APAMS:
IWC Spreadsheet:
Stream Classification:
Nutrient Sensitivity:
Instream Data:
x
x
nr
x
facility already required to meet advanced tertiary limits
facility still not taking instream data
Brief of WLA Analysis
Previous WLA's
1976: facility had recommended secondary limits for discharge to Waccamaw River, per memorandum
1977: WLA completed for discharge to unnamed tributary to Gum Swamp with 5 / 2 / 6 and 1,000 fecal
1983: facility was modeled, (zero 7010's) and limits of 5 (8) and 2 (4) were developed. The final WLA indicates limits of
15 / 4 / 6. No information exists as to why this change took place other than a memo indicating that 'single family
discharges and upland drainage area discharges' have minimum effluent limits. An attachment to this memo is
mentioned for further explanation, but it does not exist in this file.
1984: facility was remodeled and given limits of 5 (7) and 2 (2) . Comments on the Fact Sheet indicate a desire for year
' round limits of 10 / 4 and that modeling of swamp water streams is inappropriate. None -the -less, the more
stringent recommendations were finalized.
1988: "Columbus County Schools System" file. Letters in this file indicate the requirement and need for instream
monitoring. It looks as if each school was given one downstream monitoring location and a requirement to
monitor at those locations. Thus far I've not seen any instream monitoring_
1989: renewal of WLA with recommendations of 5 (10) and 2 (4) per WiRO recommendations and letter sent to
Columbus County Board of Education. Facility was soon afterwards put under an SOC to schedule removal. No
instream monitoring took place and was re -recommended.
13 April, 1994
Per telephone call with WRO, facility is having trouble finding suitable land for subsurface disposal, but they are pursuing
this option fervently. They are currently under SOC, thus these Permit recommendations would currently be moot. If they
are not able to go subsurface, these limits will apply. The plans for this option are due by May, 1994. Currently, 11 they
are not able to cease discharge by February, 1995 these limits will take effect.
A letter, (included with the Staff Report) from the Columbus County Schools indicates that facility "is presently under an
SOC to cease discharge within the next two years." [ January 6, 1994 ] Staff Report indicates that school system is looking
for a site for an underground disposal system, [scheduled construction completion February, 1995]. Region commented
that facility is making adequate progress towards meeting the SOC requirements and the Permit should be renewed if no
adverse public comment.
Basin Issues
Due to isolated condition of non -municipal dischargers, regionalization seems unlikely. Under review for future basin
plans. Current policy of schools, (i.e. to non -discharge) seems the best possible alternative.
DMR's
Facility is discharging up to their permitted limit on a regular basis.
No data at all for July and August
Chlorine levels are excessive, (and on occasion, fecals are also elevated even though chlorine is high)
BOD is well below SOC limit of 20 mg/I. Facility probably cannot meet NH3-N limit.
Still no instream data in Central Files.

NPDES WAS 1h LOAD ALLOCATION
PERMIT NO.: NC0043745
PERMITTEE NAME: Columbus County Schools
FACILITY NAME: Old Dock Elementary School
Facility Status: Existing
Permit Status: Renewal
Major Minor
Pipe No.: 001
Design Capacity: 0.005 MGD
Domestic (% of Flow): 100 %
Industrial (% of Flow):
Comments:
RECEIVING STREAM: UT to Gum Swamp Run
Class: C-Swamp
Sub -Basin: 03-07-57
Reference USGS Quad: K 24 NE (please attach)
County: Columbus
Regional Office: Wilmington Regional Office
Previous Exp. Date: 9/30/94 Treatment Plant Class: I
Classification changes within three miles:
Requested by: Dana Bolden ' U Date: 2/28/94
�1
Prepared by: f .1,------._ - Date: / z /4 Y
Reviewed by: .�Z`,J nd Date:
.z.r/
Modeler
Date Rec.
3
Oki 5'-
rl'117
Drainage Area (mil ) o-r-,
Avg. Streamflow (cfs): tl!A
7Q10 (cfs) 0.0 Winter 7Q10 (cfs)
�•a
30Q2 (cfs) 0.0
Toxicity Limits: IWC % Acute/Chronic
Instream Monitoring:
Parameters -v,, , elAt61 bvgd ox me.0 fs c"1 c ri rtm .) cdNcklA tw fd
Upstream Location &bow. aver i r. pi)
Downstream Location 0.6s cm%n atuJOVcRalmv,. ow k
dWNatn cS-te►butucc rot tkt ih rux c1
Effluent
Characteristics
Summer
Winter
BOBS (mg/1)
S . 0
rv- o
NH3-N (mg/1)
a- n
It0
D.O. (mg/1)
6.0
6.0
TSS (mg/1)
3o
30
F. Col. (/100 ml)
zao
ZOJ
pH(SU)
G-g
6-et
Rya Iovq L
CklawNc (.r[S it)
M., Nrto2
rAon,,*' R-
PWI "I`rir
7
F,i }' .;i .,.._
Comments: EAI-WAN(PXI -ct zziAnx Pcse.mrr t. "v15 uJfl.L
F(CAL.crY 130 Mc-r «SQ

Facility Name:
NPDES No.:
Type of Waste:
Facility Status:
Permit Status:
Receiving Stream:
Stream Classification:
Subbasin:
County:
Regional Office:
Requestor:
Date of Request:
Topo Quad:
FACT SHEET FOR WASTELOAD ALLOCATION
Request # 7777
Old Dock Elementary School - Columbus County Schools
NC0043745
Domestic - 100%
Existing
Renewal
unnamed tributary to Gum Swamp Run
C - Swamp
03-07-57
Columbus
Wilmington
Bolden
3/4/94
K24NE
Wasteload Allocation Summary
(approach taken, correspondence with region, EPA, etc.)
Stream Characteristic:
USGS #
Date:
Drainage Area (mi2):
Summer 7Q10 (cfs):
Winter 7Q10 (cfs):
Average Flow (cfs):
30Q2 (cfs):
IWC (%):
Facility under SOC to cease discharge
EX1.51-1 Advanced tertiary limits will be implemented if facility does not cease discharge
Special Schedule Requirements and additional comments from Reviewers:
0.0
0.0
0.0
0.0
t90%
Recommended bye - ---
Farrell Keough
Reviewed by
Instream Assessment:
Date: :3 Age,L, 15,)
Date: L(1 ` L/ (6 Ll
Regional Superviso L il- k-Th ' r r— Date: ` t -- `Z
Permits & Engineering: 1?)7 i;,e%
RETURN TO TECHNICAL g BY: )11 Cu 13 161°1 1/
u
Date: 1//%04

2
Existing Limits:
Wasteflow (MGD):
BOD5 (mg/1):
NH3N (mg/1):
DO (mg/1):
TSS (mg/1):
Fecal Coliform (/100 ml):
pH (SU):
Residual Chlorine (µg/1):
Oil & Grease (mg/1):
TP (mg/1):
TN (mg/1):
There shall) be no discharge
000 tiv fir':
Recommended Limits:
Wasteflow (MGD):
BOD5 (mg/1):
NH3N (mg/1):
DO (mg/1):II
TSS (mg/1):
Fecal Coliform (/100 ml):
pH (SU):
Residual Chlorine (µg/l):
Oil & Grease (mg/1):
TP (mg/1):
CONVENTIONAL PARAMETERS
Monthly Average
Summer Winter
0.005
5.0 10.0
2.0 4.0
6.0 6.0
30 30
1,000 1,000
6-9 6-9
monitor monitor
nr nr
nr nr
nr nr
of floating solids or visible foam in other than trace amounts.
frfl i'u-{V ✓ —1
Monthly Average
Summer Winter
0.005
5.0 10.0
2.0 4.0
6.0 6.0
30 30
200 200
6-9 6-9
monitor monitor
nr nr
nr nr
WQorEL
WQ
WQ
WQ Do
TN (mg/1): nr nr
There shall be no discharge of floating solids or visible foam in other than trace amounts.
delAd voiuhAt-vtA:-Ive
Limits Changes Due To:
Parameter(s) affected:
Fecal Coliform current standard [ .0211 (b) (3) (E)
x Parameter(s) are water quality limited. For some parameters, the available load capacity of
the immediate receiving water will be consumed. This may affect future water quality based
effluent limitations for additional dischargers within this portion of the watershed.
OR
No parameters are water quality limited, but this discharge may affect future allocations.

3
INSTREAM MONITORING REQUIREMENTS
Upstream Location: above discharge point [write "No Flow" on DMR if stream is dry]
Downstream Location: 0.35 miles downstream on an unnamed tributary at unimproved dirt road
Parameters: Temperature, dissolved oxygen, fecal coliform, conductivity
Special instream monitoring locations or monitoring frequencies:
MISCELLANEOUS INFORMATION & SPECIAL CONDITIONS
Adequacy of Existing Treatment
Has the facility demonstrated the ability to meet the proposed new limits with existing treatment
facilities? Yes No
If no, which parameters cannot be met?
Would a "phasing in" of the new limits be appropriate? Yes No
If yes, please provide a schedule (and basis for that schedule) with the regional
office recommendations:
If no, why not?
Special Instructions or Conditions
Wasteload sent to EPA? (Major) (Y or N)
(If yes, then attach updated evaluation of facility, including toxics spreadsheet, modeling analysisif
modeled at renewal, and description of how it fits into basinwide plan)
Additional Information attached? (Y or N) If yes, explain with attachments.