NC0055786_authorization to construct_19831011

North Carolina Department of Natural
Resources &Community Development
DIVISION OF
ENVIRONMENTAL
MANAGEMENT
Robert F. Helms
Director
James B. Hunt, Jr., Governor Joseph W. Grimsley, Secretary Telephone [phone]
October 11, 1983
Honorable Dwight Hinkle
Mayor
City of Lexington
28 West Center Street
Lexington, North Carolina 27202
SUBJECT: Permit No. NC0055786
Authorization to Construct
City of Lexington
Regional Wastewater Treatment Plant
EPA Project No. C370617-01-A
Dear Mayor Hinkle:
The final plans and specifications for the subject project have been
reviewed and found to be satisfactory. Authorization is hereby granted for
the construction of a new 5.5 mgd wastewater treatment plant to consist of:
first stage influent lift station with 3 screw pumps at 4,300 gpm each,
one manual and one mechanical bar screen, a detritor type grit removal
system, influent flow measuring, second stage influent lift station with
3 screw pumps at 4,300 gpm each, two primary clarifiers, raw sludge
pumping station with lime addition facilities, two roughing filters with
filter recirculation pumps, six aeration basins, caustic feed system,
aeration recirculation pump at 2,000 gpm, two final clarifiers, three
sludge recycle pumps with two at 2,100 gpm and one at 1,050 gpm, two
effluent polishing lagoons with floating aerators and groundwater
monitoring wells, chlorine disinfection facilities, three anaerobic
sludge digesters and one sludge storage tank, sludge drying beds (192,000
sq. ft.), potable water supply, laboratory/administration building,
utility building, instrumentation/sampling/control equipment, and standby
power facilities.
You are cautioned not to advertise or initiate construction until
so notified by EPA, if Federal Funding is desired for project construction.
Instructions regarding bidding procedures and the authority to advertise
for construction bid will be sent to you, with the Grant offer from EPA.
The Permittee shall employ an actively State certified wastewater
treatment plant operator to be in responsible charge of the wastewater
treatment facilities. Such operator must hold a State certificate of the
grade at least equivalent to the classification assigned to the wastewater
treatment facilities by the Certification Commission. When a new chief
operator must be obtained to be in responsible charge of the new facilities,
it is required that this be done by the time the construction of the facili-
ties is 50% completed.
POLLUTION PREVENTION PAYS
P. O. Box 27687 Raleigh, N. C. 27611-7687
An Equal Opportunity Affirmative Action Employer

_ Honorable Dwight Hinkle
Page Two
October 11, 1983
This Authorization to Construct is issued in accordance with Part 3,
Paragraph C of NPDES Permit No. NC0055786 issued June 20, 1983, and shall
be subject to revocation unless the wastewater treatment facilities are
constructed in accordance with the approved plans, specifications, support-
ing documents, and are in compliance with the conditions and limitations
specified in Permit No. NC0055786.
During the construction of the proposed additions/modifications, the
Permittee shall continue to properly maintain and operate the existing
wastewater treatment facilities at all times, and in such manner, as
necessary to comply with the effluent limits specified in the NPDES Permits.
The selling or free distribution of wet, dried, composted sludge or
sludge like materials from wastewater facilities without prior review and
approval by this Division is illegal.
The Permittee shall obtain a sludge analysis and a sludge E.P. toxicity
analysis; and obtains approval of these analyses from the Division of Health
Services, Solid Waste Management Branch prior to the disposal of any sludge
from the new wastewater treatment plant. Copies of the analyses, supporting
documents, and approvals shall be submitted to the Division of Environmental
Management Water Quality Section and the Winston-Salem Regional Office.
Three monitoring wells shall be installed down grade from the effluent
lagoons within a 100 ft. radius of site coordinates (E22 + 00, N66 + 50),
(E21 + 50, N71 + 25), and (E18 + 50, N71 + 50). A fourth monitoring well shall
be installed if required by the NCDEM Winston-Salem Regional Office (WSRO).
NCDEM WSRO Groundwater personnel shall be on site during construction of the
monitoring wells and shall approve the specific location of the monitoring wells
prior to construction. The groundwater monitoring wells shall be monitored
semi-annually for the following parameters: chlorides, nitrates, BOD ,
COD , and heavy metals. The results of the semi-annual monitoring shall be
submitted to the NCDEM WSRO. Additional parameters may be required if deemed
necessary by the NCDEM WSRO based on the semi-annual monitoring of parameters
noted above. A variance to the N.C. Well Construction Standards must be
obtained for monitor wells by written request to the NCDEM WSRO since the
well standards require permanent observation wells to be constructed in
accordance with requirements for water supply wells.
The effluent polishing lagoons in cut areas shall be lined with 10
inches of material compacted to a maximum permeability of 10-7 cm/sec.
The fill area shall be compacted to provide a maximum permeability of 10-4
cm/sec to 10- cm/sec. These permeability values shall apply to both the
bottom and sides of the lagoon.
The facilities shall be constructed in accordance with the requirements
of the North Carolina Sedimentation Pollution Control Act.
One (1) set of final approved plans and specifications is to be forwarded
to you, one (1) set to the Environmental Protection Agency (EPA), and two
(2) sets to the Corps of Engineers.

Honorable Dwight Hinkle
Page Three
October 11, 1983
If you have any questions or need additional information, please contact
Mr. W. S. Hoffman, telephone number 919/733-6900.
Sincerely,
Original Signed By
FORREST R. WESTALL
FOR
Robert F. Helms
Director
LH:tm
cc: Davidson County Health Department
J. N. Pease Associates
Mr. Walter Taft
Mr. William Mills
Mr. Russell Radford
Mr. Robert Joyce
Mr. Bobby Blowe
Ms. Brenda Chesson
Mr. W. S. Hoffman
Mr. Brian Moore
EPA
GPF