NC0050342_staff comments_19890417

State of North Carolina
Department of Natural Resources and Community Development
Division of Environmental Management
512 North Salisbury Street • Raleigh, North Carolina 27611
James G. Martin, Governor R. Paul Wilms
William W. Cobey, Jr., Secretary April 17, 1989 Director
Mr. Stanley B. Webb, Plant Manager
Muddy Creek Plant
City of Winston-Salem
Box 2511
Winston-Salem, NC 27102
Dear Mr. Webb:
I am writing in response to your letter of March 29 regarding
the draft permit for the Muddy Creek WWTP (NC0050342). You were
concerned about the following issues:
(1) Upstream Monitoring Point
Your upstream monitoring point may be changed to
Idols Dam. The monitoring sheets currently submitted
list US 158 as the sampling location. You should cor-
rect this on future data sheets and indicate whether you
are sampling in the pool or downstream of the dam.
(2) Downstream Monitoring Point
You may continue to collect samples near the US 64
bridge. When the new bridge at Highway 64 is completed,
you should investigate the feasibility of sampling from
it.
(3) Instream Monitoring Frequency
Per NCAC 2B.0508, the minimum monitoring frequency
for dissolved oxygen, temperature, and fecal coliform
for a class IV facility is three times per week if the
discharge is to "water quality limited" waters. The
secondary limits assigned to the Lower Muddy Creek plant
reflect "effluent limited" waters, and thus the instream
monitoring frequency for these parameters may be changed
to one time per week. It is standard procedure to
include conductivity monitoring in all municipal permits
P.O Box 27687, Raleigh, North Carolina 27611-7687 Telephone [phone]
An Equal Opportunity Affirmative Action Emolover

as a tracer for the presence of wastewater, and ammonia
and BOD5 monitoring in all major municipal permits where
existing monitoring data are insufficient. The
frequency for these three parameters should also be
weekly. The instream monitoring requirement for lead
should be monthly. All daily measurement frequencies
listed in the permit refer to effluent samples.
(4) Effluent Dissolved Oxygen Monitoring
The effluent dissolved oxygen monitoring require-
ment may be deleted. However, the City may want to
investigate a method of measuring effluent dissolved
oxygen near the outfall since future analyses will
assume an effluent DO concentration of zero unless the
City has provided DEM with data supporting an alterna-
tive assumption.
(5) Toxicity Dilution
You requested that the instream waste concentration
be recalculated using the 7Q10 of Muddy Creek in addi-
tion to that of the Yadkin River. Muddy Creek is
approximately 200 feet downstream of the discharge. The
water in this stretch of stream should also be pro-
tected, so the bioassay dilution factor will remain at
4%.
I hope that the Division's response is satisfactory to the
City. However, if this letter does not adequately address your
concerns, you have the right to an adjudicatory hearing upon writ-
ten request within thirty (30) days following receipt of the
issued permit. This request must be in the form of a written
petition, conforming to Chapter 150B of the North Carolina General
Statutes, and filed with the Office of Administrative Hearings,
Post Office Drawer 11666, Raleigh, North Carolina 27604. Unless
such a request is received by this Division, the requirements con-
tained in the issued permit shall be final and binding.
CC:
Arthur Mouberry
Trevor Clements
Steve Mauney
Central Files
WLA File
R. Paul Wilms