NC0023736_modification request_20210519 (3)

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Lower Creek Wastewater Treatment
Public Utilities
PO Box 958
Lenoir, NC 28645
5/19/2021
Michael Montebello
Supervisor, Municipal Permitting Unit
Division of Water Resources
North Carolina Department of Environmental Quality
Dear Sir:
As per our conference call including yourself, Mr. Gary Perlmutter, Mr. Tim Heim and myself
on May 18th, 2021, I am following up with a request for a permit modification for NC0023736
the City of Lenoir Gunpowder Creek Wastewater Treatment plant.
I respectfully request that the permit modification include a compliance schedule for Copper as
the limit assigned is a monthly average of 15.4 ug/1 and an 18.7 ug/1 daily maximum. I
understand that Lead and Zinc limits have also been issued on the new permit as well, but I do
not foresee issues with meeting those limits as assigned, therefore I should not need a
compliance schedule for those parameters.
Mr. Perlmutter did offer to include the compliance schedule as the draft permit was being
written. I inadvertently declined to have it included and the draft was sent out for public notice
and approved and in effect on April 1, 2021. I now understand more clearly that I should have
accepted the compliance schedule before the permit came into effect, as it is much more entailed
to request one after the permit is in effect.
As I was considering the need for a compliance schedule, I looked at the 2 industries that
discharge to the Gunpowder Wastewater Treatment plant that have Copper limits assigned and
also the Gunpowder effluent copper results obtained over the past 4 years. Seemingly, no red
flags of violations were seen.
Currently the Lenoir Mirror industry has a copper limit assigned of 1.2 mg/1 and Beocare has a
copper limit of 0.300 mg/1 assigned in their permits respectively. Between 2017 and 2020 the
copper data results indicated Lenoir Mirror had violated their permit limit 1 time with a result of
1.47 mg/1 during the 4th quarter of 2017. Beocare had not violated their permit limit at all during
that same four-year period.

Of the 17 sample results from that same four-year period, the Gunpowder Creek WWTP effluent
had 64.7% of the results that would not have violated the new copper permit limits. Half of the
64.7% results were BDL (below detection limit) leaving the remaining 35.3% that would have
been in violation of the new copper limits.
The two industrial permit limits are where I went wrong in considering the compliance schedule.
As I look at calculating HWA, I see that both of these current permit limit assignments would
now be considered over allocation on the HWA. With all the previous information showing that
no violations had occurred on copper results, I incorrectly concluded that a compliance schedule
wouldn't be needed. However, upon further review and closer examination of the drastically
lower numbers that will be required for both industries to not be over allocated for copper and
for the plant effluent to be able to meet the new permit limits, a compliance schedule will be
needed.
Note: I have spoken the CEO of Lenoir Mirror today, and he has informed me that a new copper
removal system will be installed and running in the next couple of weeks. When they have it
properly running our pretreatment team will set out the composite sampler for a couple of weeks
to get some removal results. Hopefully this will take care of the copper issues that we are facing
at this time. I will keep everyone updated as to the results obtained.
Thank you for your consideration.
Sincerely,
t=Lew Yriplett
Elisa Triplett, WWTP Superintendent
[e-mail]
[phone]