NCG510207_staff Report_19950918

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SOC PRIORITY PROJECT: Yes_ No X
To: Permits and Engineering Unit
Water Quality Section
Attention: Charles Alvarez
Date: September 18, 1995
NPDES STAFF REPORT AND RECOMMENDATION
County: Mecklenburg
MRO No.: 95-127
Permit No. NCG510207 - -
PART I - GENERAL INFORMATION
1. Facility and Address: Colonial Pipeline Company
Post Office Box 87
Paw Creek, North Carolina 28130
2. Date of Investigation: N/A
3. Report Prepared By: Samar Bou-Ghazale, Env. Engineer I
4. Persons Contacted and Telephone Number: Mr. Dan Miller,
District Environmental Project Manager; [phone]
5. Directions to Site: From the junction of Highway I-85 and
Highway 27 in Charlotte, travel west on Highway 27 (Freedom
Drive) approximately three (3) miles to Old Mt. Holly Road.
Turn right onto Old Mt. Holly Road and travel approximately
0.2 mile to intersection with Kenstead Circle. Proceed on
Kenstead Circle approximately 200 feet. The entrance to
Colonial Pipeline Company is located on the left side of the
road.
6. Discharge Point(s). List for all discharge points:
Latitude. 350 17' 17" Longitude: 800 56' 08"
Attach a U.S.G.S. map extract and indicate treatment facility
site and discharge point on map.
USGS Quad No.: F 15 SW USGS Quad Name: Mountain Island Lake
7. Site size and expansion are consistent with application?
Yes X No_ If No, explain:
8. Topography (relationship to flood plain included): Moderately
hilly, with slopes of 3 to 7%. The site is not located in a
flood plain.
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9. Location of nearest dwelling: None within 500 feet of the
discharge point.
10. Receiving stream or affected surface waters: Unnamed
tributary to Gum Branch.
a. Classification: C
b. River Basin and Subbasin No.: Catawba River Basin;
030834
C. Describe receiving stream features and pertinent
downstream uses: Discharge will take place into an
unnamed tributary to Gum Branch. The receiving stream
flows through a low density community with the downstream
uses typical of Class C waters.
PART II - DESCRIPTION OF DISCHARGE AND TREATMENT WORKS
1. a. Volume of wastewater to be permitted: 0.0648 MGD
b. What is the current permitted capacity of the wastewater
treatment facility? 0.0648 MGD
C. Actual treatment capacity of the current facility
(current design capacity)? 0.0648 MGD
d. Date(s) and construction activities allowed by previous
Authorizations to Construct issued in the previous two
years: An Authorization to construct for the Groundwater
remediation facility was issued on July 29, 1994.
e. Please provide a description of existing or substantially
constructed wastewater treatment facilities: The existing
groundwater treatment system consists of monitoring
wells, recovery wells, oil/water separator, diffused air
unit, and an activated carbon adsorption unit.
f. Please provide a description of proposed wastewater
treatment facilities: The proposed groundwater
treatment system will include the addition of four
groundwater recovery wells and a recovery trench. The
existing monitor wells MW-38, MW-39, and MW-41 will also
be retro-fitted as vacuum -enhanced recovery wells. The
recovered ground water will be treated through a separate
oil/water separator and then routed to the existing
treatment system.
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g. Possible toxic impacts to surface waters: Due to nature
of the wastewater there could be some toxicity concern.
h. Pretreatment Program (POTWs only): N/A.
2. Residuals handling and utilization/disposal scheme: Generation
of residuals is not expected.
3. Treatment plant classification (attach completed rating
sheet): Proposed, no rating given.
4. SIC Code(s): 5171
Primary: 53
Main Treatment Unit Code: 53000
PART III - OTHER PERTINENT INFORMATION
1. Is this facility being constructed with Construction Grant
Funds or are any public monies involved (municipals only)?
N/A.
2. Special monitoring or limitations (including toxicity)
requests: Toxicity may need to be monitored and/or limited.
3. Important SOC, JOC or Compliance Schedule dates: (please
indicate) N/A.
4. Alternative Analysis Evaluation: Has the facility evaluated.
all of the non -discharge options available. Please provide
regional perspective for each option evaluated.
Spray irrigation: This option has been evaluated and not
found to be an alternative due to site topography and low
hydraulic conductivity of the soil.
Connection to regional Sewer System: The Charlotte -Mecklenburg
Utility Department will not accept treated groundwater into
its sewer system.
Discharge to an infiltration gallery: The use of an
infiltration gallery was evaluated and not found to be an
alternative due to the presence of shallow bedrock.
5. Air Quality and/or Groundwater concerns or hazardous material
utilized at this facility that may impact water quality, air
quality or groundwater? Contaminated groundwater already
exists at the site. Hazardous material stored at the site may.
pose a threat to groundwater. An Air Quality Permit for this
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facility may be required by Mecklenburg County.
PART IV - EVALUATION AND RECOMMENDATIONS
Colonial Pipeline Company is requesting an amendment to .its
NPDES General Permit No. NCG510207. Additional influent
groundwater pumps are to be installed on a different part of the
site.
It is recommended that the NPDES Permit be amended to provide
for the proposed additions.
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Si ature o R ort Preparer Date
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Water Qualit
ional Supervisor
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Date