NC0021156_Speculative Limits_20040220

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Michael F. Easley, Governor
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State of North Carolina
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William G. Ross, Jr., Secretary
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Department of Environment and Natural Resources
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Alan W. Klimek, P.E., Director
Division of Water Quality
Mr. Don Price, Utilities Director
City of Mount Holly
P.O. Box 406
Mount Holly, North Carolina 28120
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Dear Mr. Price:. /
February 20, 2004
Subject: Speculative Effluent Limits
Mount Holly WWTP
NPDES Permit NCO021156
Gaston County
This letter is in response to your request for speculative effluent limits for a proposed expansion to 6
MGD at the Mount Holly W vTP. Currently, this facility is permitted for 4 MGD.
Receiving Stream. This facility discharges to the Catawba River, classified WS-IV CA waters. This portion
of the Catawba River and its tributaries, from the Mountain Island Lake dam to the Lake Wyle dam, are
subject to the Lake Wylie Nutrient Management Strategy. Eutrophic conditions in Lake Wylie and several of
its major tributaries have caused DWQ and South Carolina DHEC to develop point and nonpoint nutrient
control strategies for the Lake Wylie Watershed.
Speculative Limits. Based on available information, speculative effluent limits for a proposed discharge of 6
MGD to the Catawba River are presented in Table 1. A complete evaluation of these limits and monitoring
frequencies, in addition to monitoring requirements for metals and other toxicants, will be addressed upon
receipt of a formal NPDES permit modification request.
TABLE 1. Speculative Limits for Mount Holly WWTP, NCO021156
E15FLUENT
CHARACTERISTIC
FFFLUEN'T U MTTAT>IONS
I1�oritthtly Average
WeeIdy Avera e
Ili 114aximu
Flow
6 MGD
BOD5
30.0 mg/1
45.0 mg/1
TSS
30.0 mg/1
45.0 mg/1
Fecal Coliform
200/100 ml
400/100 ml
TRC
28 µg/1
Total Nitrogen' (summer only)
6 mg/L
Total Phosphorus
1 mg/L
Notes:
1) You may choose to have the total nitrogen limit expressed as an annual mass load based on a summer limit of
6mg/L and a winter limit of 12 mg/L.
Engineering Alternatives Analysis {1',AA). Please note that the Division cannot guarantee that an NPDES
permit modification for expansion to 6 MGD will be issued with these speculative limits. Final decisions can
only be made after the Division receives and evaluates a formal permit application for the City's proposed
discharge. In accordance with the North Carolina General Statutes, the practicable wastewater treatment and
disposal alternative with the least adverse impact on the environment is required to be implemented.
North Carolina Division of Water Quality [phone]
1617 Mail Service Center FAX [phone]
Raleigh, North Carolina 27699-1617 On the Internet at http://h2o.enr.state.nc.us/

Therefore, as a component of all NPDES permit applications for new or expanding flow, a detailed
engineering alternatives analysis (EAA) must be prepared. The EAA must justify requested flows, and
provide an analysis of potential wastewater treatment alternatives. Alternatives to a surface water discharge,
such as spray/drip irrigation, wastewater reuse, or inflow/infiltration reduction, are considered to be
environmentally preferable. A copy of the EAA requirements is attached to this letter. Permit applications
for new or expanding flow will be returned as incomplete if all EAA requirements are not adequately
addressed. If you have any questions regarding these requirements, please contact the DWQ NPDES Unit
at 919-733-5083.
State Environmental Policy Act SEPA EA EIS Requirements. A SEPA EA/EIS document must be
prepared for all projects that 1) need a permit; 2) use public money or affect public lands; and 3) might have a
potential to significantly impact the environment. For new wastewater discharges, significant impact is
defined as a proposed discharge of >500,000 gpd and producing an instream waste concentration of > 33%
based on summer 7Q10 flow conditions. For existing discharges, significant impact is defined as an
expansion of > 500,000 gpd additional flow. Since your existing facility is proposing an expansion of
>500,000 gpd additional flow, you must prepare a SEPA document that evaluates the potential for
impacting the quality of the environment. The NPDES Unit will not accept an NPDES permit
application for the proposed expansion until the Division has approved the SEPA document and
sent a Finding of No Significant Impact (FONSI) to the State Clearinghouse for review and
comment. A SEPA Environmental Assessment (EA) should contain a clear justification for the proposed
project. If the SEPA EA demonstrates that the project may result in a significant adverse effect on the quality
of the environment, you must then prepare a SEPA EIS (Environmental Impact Statement). Since your
proposed expansion is subject to SEPA, the EAA requirements discussed above will need to be
folded into the SEPA document. The SEPA process will be delayed if all EAA requirements are not
adequately addressed. If you have any questions regarding SEPA EA/EIS requirements, please contact
Alex Marks with the DWQ Planning Branch at [phone], ext. 555.
Should you have any questions about these speculative limits or NPDES permitting requirements, please feel
free to contact Toya Fields at [phone], extension 551.
4inerely,
tl�David A. Goodrich
Supervisor, NPDES Unit
Attachment: EAA Guidance Document
cc: Kevin C. Kirkland, PE
JTH Associates, LLC
P.O. Box 2585
Greer, South Carolina 29652-2585
(without attachment)
Mooresville Regional Office, Water Quality Section
NPDES Unit
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JTH ASSOCIATES, LLC
ENGINEERS & PLANNERS
P.O. BOX 2585
GREER, SOUTH CAROLINA 29652-2585
PHONE [phone]
FAX [phone]
April 11, 2003
Mr. David Goodrich
Director ofNPDES Permits
NCDENR
1617 Mail Service Center
Raleigh, NC 27699-1617
RE: City of Mount Holly
Speculative Limits
NPDES Permit No. 0021156
Dear Mr. Goodrich,
JTH Associates, LLC has been retained by the City of Mount Holly to engineer
improvements to the Mount Holly Water System, Attached is a copy of the letter from
Don Price, Utilities Director, stating this fact.
In order to design improvements for the Mount Holly Water System, I am requesting the
Speculative Limits of the Mount Holly discharge for the current discharge flow rates of
4 MGD and future design flow rates of 6 MGD and 8 YGD. In addition, please provide
any nutrient limits such as nitrogen and phosphorous. p
Thank you very much for your assistance. If you should have any questions, please call.
Regards,
JTH Associates, LLC
Kevin C. Kirkland, PE
Associate
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City of Mount Holly
131 South Main Street
Post Office ce Sox 406
Mount Holly. North Carolina 28120
Phone; (704) 827-Ml Fax: [phone]M
Robert D. Black, Mayor
Frank McLean, Councilman
Phyllis Harms, Councilwoman
Michael HeIM, Councilman
April 10, 2003
Mr. David Goodrich
Director of NPDES Permits
NCDENR
1617 Mail Service Center
Raleigh, NC 27699-1617
Jim Hope, Mayor Pro Tern
Bryan Hough, Councilman
Pat Hubbard, Councilwoman
David Kaus, City Manager
RE: JTH Associates, LIC
Engineering Firm Representing the City of Mount Holly
Dear Mr, Goodrich,
T e City of Mount Dolly has retained the services of JTH Associates, LLC to design modifications to lira .Ruw Water
Treatment and Waste Water Treatment facilities pertaining to the City of Mount Holly Water System.
Therefore, we are reclucsting data pertaining to the City of Mount Holly Water System be released to the follomring
engineers employed by JTH Associates for the purpose of improving our system: John T. Hannah, PF and
Kevin C. Kirkland. PE_
'four assistance with this matter is appreciated.
Regards,
City of .Mount .Holly
Don Price
Utilities Director