NC0004685_Authorization to Construct_19980113

StE to of North Carolina
Department of Environment
and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
Ms. Lacy Ballard
PPG Industries, Inc.
940 Washburn Switch Rd.
Shelby, North Carolina 28150
Dear Ms. Ballard:
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c) E N R
January 13, 1998
Subject: Permit Number NC004685
Authorization to Construct
PPG Ind./Shelby Plant
Cleveland County
A letter of request for an Authorization to Construct (ATC) was received October 21, 1997
by the Division and final plans, specifications, and pilot test data for the subject project have been
reviewed and found to be satisfactory. Authorization is hereby granted for the construction and
installation of the proposed components to upgrade the existing 1.3 MGD wastewater treatment plant
with outfall 001 discharging to Brushy Creek ii. the Broad River Basin.
This ATC allows the installation of a bentonite clay feed system and additional tanks,
mixers, pumps, piping, valves, and control equipment with feed to the aeration splitter box.
This Authorization to Construct is issued in accordance with Part III, Paragraph C of
NPDES No. NC0004685 issued September 28, 1994 and shall be subject to revocation unless the
water treatment facilities are constructed in accordance with the conditions and limitations specified
above, and in Permit No. NC0004685.
Any sludge generated from this treatment facility must be disposed of in accordance with
G.S. 143-215.1 and in a manner approved by the North Carolina Division of Water Quality.
In the event that the facility fails to perform satisfactorily, including the creation of nuisance
conditions, the Permittee shall take immediate corrective action, including those as may be required
by this Division, such as the construction of additional or replacement water treatment or disposal
facilities.
The Mooresville Regional Office, telephone number [phone], shall be notified at
least forty-eight (48) hours in advance of operation of the installed facilities so that an in -place
inspection can be made. Such notification to the regional supervisor shall be made during the
normal office hours from 8:00 a.m. until 5:00 p.m. on Monday through Friday, excluding State
Holidays.
Upon completion of construction and prior to operation of this permitted facility, a
certification must be received from a professional engineer certifying that the permitted facility has
been installed in accordance with the NPDES Permit, this Authorization to Construct and the
approved plans and specifications. Mail the Certification to the Permits and Engineering Unit, P.O.
Box 29535, Raleigh, NC 27626-0535.
P.O. Box 29535, Raleigh, North Carolina 27626-0535 Te&ephone 919-733-5083 FAX [phone]
An Equal Opportunity Affirmative Action Employer 50% recycled. 10% post -consumer paper
04635 ATC

A copy of the approved plans and specifications shall be maintained on file by the Permittee
for the life of the facility.
Failure to abide by the requirements contained in this Authorization to Construct may subject
the Permittee to an enforcement action by the Division of Water Quality in accordance with North
' Carolina General Statute 143-215.6A to 143-215.6C.
The issuance of this Authorization to Construct does not preclude the Permittee from
complying with any and all statutes, rules, regulations, or ordinances which may be imposed by
other government agencies (local, state, and federal) which have jurisdiction.
One (1) set of approved plans and specifications is being forwarded to you. If you have any
questions or need additional information, please contact Steven D. Pellei, telephone number (919)
733-5083 extension 516.
Sincerely,
0 Q--A. Preston Ho ard, Jr., P.E.
cc: Central Files
Mooresville Regional Office, Water Quality
Training and Certification Unit
NPDES Files
Steven Pellei

DIVISION OF WATER QUALITY
October 22, 1997
MEMORANDUM
To: Rex Gleason
Thru: Matt Matthews A"".
From: Kevin Bowden 61.;
SUBJECT:
Toxicity Reduction Evaluation Progress Report - October 1997
PPG Industries -Shelby
NPDES Permit No. NC0004685
Cleveland County
This office has received and reviewed a copy of the facility's Toxicity Reduction Evaluation Quarterly
Progress Report dated October 1997. The report has been prepared by the facility's toxicity consultant, AWARE
Environmental, Incorporated (AEI). The facility entered into SOC EMC WQ No. 96-24 on March 11, 1997. Item
2(d) of the SOC requires the facility to submit quarterly progress reports by the fifteenth day of each January, April,
July, and October until completion of activities and compliance with final limits has been achieved. The facility is
required to conduct multiple concentration toxicity testing during the term of the SOC at serial effluent concentrations
of 8.25%, 16.5%, 33%, 49.5%, and 66%. The facility's NPDES Permit contains a 33% chronic limitation.
Chronic values from multiple concentration toxicity testing conducted during July, August, and September
1997 measured 57.1%. The report mentions that the WWTP has not failed an effluent toxicity test at a 33% effluent
concentration since May 1997.
Since submittal of the last quarterly progress report, PPG has continued with full-scale addition of bentonite
clay without powdered activated carbon (PAC) addition. On March 25, 1997, the facility initiated bentonite clay
addition and manually added 1000 pounds of product to the aeration basin. Currently, the facility is adding about
500 pounds of bentonite clay per day to the system. PPG anticipates reducing this amount based on two factors: the
volume of excess residuals produced by the system and results of toxicity testing.
The facility proposes to test for toxicity once per month and indicates that an increase in testing frequency
(quarterly multiple concentration testing required by the SOC) will allow the facility to evaluate and optimise clay
feed requirements. The Company is in the process of applying for an Authorization to Construct (ATC) for
conversion of the pilot unit to a permanent WWTP modification.
In summary, we congratulate the Company on its efforts to achieve compliance with its 33% chronic permit
limitation since May of 1997. In our previous progress report review dated May 21, 1997, this office expressed
concem about potential wastestream changes and how any changes may affect effluent toxicity using bentonite clay
as the chosen treatment technology. We also inquired about residual handling capabilities at PPG and noted that an
increase in residuals and residuals wasting would be expected from a bentonite clay treatment approach. It would
appear that the Company feels comfortable with the selected treatment technology. This office continues to support
source reduction activities as being the most cost effective means to toxicity reduction. We also stress the
importance of chemical substitution/optimization activities for those compounds which have been shown to
contribute to effluent toxicity. To our knowledge effluent toxicants have not been characterized, identified and/or
confirmed.
ov
ArCi
We look forward to reviewing the facility's upcoming toxicity testing data and the next quarterly progress
report due by January 15, 1998.
Should you have questions, please contact me at [phone].
cc: Don Safrit-Point Source Branch
Bob Sledge -Point Source Compliance Enforcement Unit
John Lesley -Mooresville Regional Office
Aquatic Toxicology Unit Files
Central Files