NC0063762_NOV-2023-LV-0869_20231215

Metwater, Inc.
1000 Wooddhurst Drive Monroe NC 28110 1704.506.4255 draetwaterRaol.com
12-15-23
Mr. Roberto Scheller
Water Quality Regional Operations Center
Division of Water Resources, NCDEQ
610 East Center Avenue, Ste. 301
Mooresville, NC 28115
Ref: NOV-2023-LV-0869 & Intent to Assess Civil Penalty
Carolina Village WWTP
NPDES# NC0063762
Dear Mr. Scheller,
This letter is intended to address the NOV (Notice of Violation) letter addressed to Susan
Gotshall of Carolina Village MHC, LLC, dated November 30th, 2023, wherein the monthly
average Ammonia was exceeded.
As you know, foaming issues are nothing new to the Carolina Village Wastewater Plant. Up
until recently a small upset could be corrected with sludge wasting, chlorine sprayers and
some lime. This is not the case anymore. I have never seen the foam and scum come on so
fast and stay for so long. As we discussed, foam has the potential to contribute to poor
settling and treatment leading to an array of non-compliance issues as we are seeing here.
And unfortunately the first 2 weeks of November 2023 as BOD's were > 53 mg/l and > 49
mg/l. However, the 3rd week of November shown improvements with BOD at 17mg/l, TSS
at 7.8 mg/l, NH3N at 8.1 mg/l and a fecal of 10 colonies/100ml.
We have been and continue to collect additional data and analytical results from our
influent, EQ basin, aeration basin and effluent. We have found influent constituents to be at
the high end of what should be 100% domestic, including CBOD's in the 300mg/l range and
source water (City) pH in the low to mid 7.0 S.U.
We have also identified through mixed liquor microscopy that our microorganism
predominance consist of manly filamentous bacteria with only a small population of
desired organisms. We have been injecting chlorine into the RAS and are beginning to see a
decline in filamentous bacteria and groupings of ciliates.
Working with a consultant, we tried adding hydrated lime to reach the prescribed pH of 8
to 8.5 S.U. in the aeration basin. We went through a pallet of lime (45, 501b. bags) in couple
weeks with little success. Then we switched to a 25% caustic drip into the EQ and although

we are still tweaking the drip per minute setting, we are starting to see a consistent pH of
7.5 S.U. and above.
We are currently on a path to:
1. Evaluating blower efficiency, amp draws, size of pulleys, calculating SUM as it
relates to oxygen horsepower needed
2. Adding 25% caustic to increase and maintain pH of 8.5 +/- 0.2 S.U.
3. Evaluating condition of air headers and changing filters to wire mesh to increase air
flow
4. Increase dissolved oxygen in aeration basin from its current 1.5 mg/1 to the desire
3.5 mg/1- 5.0 mg/1
5. Replacing all 8 diffusers in aeration basin
6. Evaluating need to have aeration basin emptied and any settleables removed off site
7. Continuing with the 12.5% Hypochlorite to RAS injection to control proliferation of
filamentous bacteria.
8. Leaving one blower on 24 hrs. a day. Never turning off nor cycling blower run times.
9. We have also spoken to the manufacturer of NEWCO chlorine tablets (Sanitizer) to
obtain a clear understanding of dosing requirements per gallons of water treated as
the size of the tablets fluctuate and routinely only partially dissolve preventing the
next tablet from dropping.
In closing, we respectfully ask that your office consider the remedial actions taken thus far
and our plan of action provided herein while in consideration of a civil penalty and chose
not to move forward with any further enforcement.
Should you need additional information or follow up please contact me directly by calling
704-506-4255 or emailing me at [e-mail].
Also thank you for the extension to reply.
Sincerely,
Dusty Metreyeon
ORC, Carolina Village WWTP
Metwater, Inc.
1000 Woodhurst Drive
Monroe, NC 28110
CC: "[e-mail]" <[e-mail]>;
"Emmett Conneely" <[e-mail]>;
"Jrusso" <[e-mail]>;
"[e-mail]" <[e-mail]>;
"[e-mail]" <[e-mail]>;
Page 2