NC0031879_Staff Report_20210218

State of North Carolina
Division of Water Resources

Water Quality Regional Operations Section
Staff Report

To: NPDES Unit Non-Discharge Unit Application No.: NC0031879
Attn: Diana Yitbarek Facility name: Corpening Creek WWTP

From: Lauren Armeni
Asheville Regional Office
Note: This form has been adapted from the non-discharge facility staff report to document the review of both non-
discharge and NPDES permit applications and/or renewals. Please complete all sections as they are applicable.
I. GENERAL AND SITE VISIT INFORMATION
1. Was a site visit conducted? Yes or No
a. Date of site visit: 02/05/2021
b. Site visit conducted by: Lauren Armeni & Mikal Willmer
c. Inspection report attached? Yes or No (See Laserfiche for Inspection)
d. Person contacted: Tim Horton and their contact information: [phone] ext. !!!!
e. Driving directions: Take exit 86 off of I-40 E for NC-226 S toward Marion/Shelby. Turn left onto NC-
226 S and the WWTP (3982 NC-226 S) is on the right approximately 0.5 miles down.
2. Discharge Point(s):
Latitude: 35.651658 Longitude: -81.957656
Latitude: Longitude:
3. Receiving stream or affected surface waters: Youngs Fork (Corpening Creek)
Classification: C
River Basin and Subbasin No. CTB, 03050101
Describe receiving stream features and pertinent downstream uses: River is protected for class C uses.
II. PROPOSED FACILITIES: NEW APPLICATIONS
1. Facility Classification: (Please attach completed rating sheet to be attached to issued permit)
Proposed flow:
Current permitted flow:
2. Are the new treatment facilities adequate for the type of waste and disposal system? Yes or No
If no, explain:
3. Are site conditions (soils, depth to water table, etc) consistent with the submitted reports? Yes No N/A
If no, please explain:
4. Do the plans and site map represent the actual site (property lines, wells, etc.)? Yes No N/A
If no, please explain:
5. Is the proposed residuals management plan adequate? Yes No N/A
If no, please explain:
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6. Are the proposed application rates (e.g., hydraulic, nutrient) acceptable? Yes No N/A
If no, please explain:
7.Are there any setbackconflictsfor proposed treatment, storage and disposal sites? Yes or No
If yes, attach a map showing conflict areas.
8. Is the proposed or existing groundwater monitoring program adequate? Yes No N/A
If no, explain and recommend any changes to the groundwater monitoring program:
9. For residuals, will seasonal or other restrictions be required? Yes No N/A
If yes, attach list of sites with restrictions (Certification B)
Describe the residuals handling and utilization scheme:
10. Possible toxic impacts to surface waters:
11. Pretreatment Program (POTWs only):
III. EXISTING FACILITIES: MODIFICATION AND RENEWAL APPLICATIONS
1. Are there appropriately certified Operators in Charge (ORCs) for the facility? Yes No N/A
ORC: Tim Horton Certificate #:1008211 Backup ORC: Jeffery Sanders Certificate #:992546
2. Are the design, maintenance and operation of the treatment facilities adequate for the type of waste and disposal
system? Yes or No
If no, please explain: Both primary clarifiers are currently being used as EQ basins because the primary clarifier
sweep arms and drive units are not operational.
Description of existing facilities:
Influent pump station,
Mechanical step bar screen backed up by a manual bar screen,
Grit chamber,
Two circular primary clarifiers (both of these clarifiers are currently being used as EQ basins),
Two aeration basins (one is in operation),
Two circular secondary clarifiers,
Tertiary filters,
Baffled chlorine contact chamber,
Gas chlorination and sulfur dioxide dechlorination,
Step aeration,
Two gravity sludge thickeners,
One aerobic digester
Proposed flow: No Change.
Current permitted flow: 3.0 MGD
Explain anything observed during the site visit that needs to be addressed by the permit, or that may be important
for the permit writer to know (i.e., equipment condition, function, maintenance, a change in facility ownership,
etc.) Facility equipment is aging, and some equipment needs to be brought off line in the future for repairs.
Both primary clarifiers are currently being used as EQ basins. The sweep arms and drive units are broken
on both of the primary clarifiers and the middle wells are rusting out. Additionally, the pipes from the
primary clarifiers to the thickeners are clogged, so wasting cannot be done. One of the two aeration basins
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is currently in operation, although the second aeration could be put back online if cleaned. The tertiary
filters are not in use at this time. The ORC indicated they would like to have them operational at some
point, but they will first need to be rehabilitated. It is recommended thatthe tertiary filters be added back
to the permit since they are still a system component, just not currently in operation. See inspection report
for further details on system components.
3. Are the site conditions (e.g., soils, topography, depth to water table, etc) maintained appropriately and adequately
assimilating the waste? Yes or No N/A
If no, please explain:
4. Has the site changed in any way that may affect the permit (e.g., drainage added, new wells inside the compliance
boundary, new development, etc.)? Yes or No
If yes, please explain:
5. Is the residuals management plan adequate? Yes or No
If no, please explain:
6. Are the existing application rates (e.g., hydraulic, nutrient) still acceptable? Yes or No N/A
If no, please explain:
7. Is the existing groundwater monitoring program adequate? Yes No N/A
If no, explain and recommend any changes to the groundwater monitoring program:
8. Are there any setback conflicts for existing treatment, storage and disposal sites? Yes or No
If yes, attach a map showing conflict areas.
9. Is the description of the facilities as written in the existing permit correct? Yes or No
If no, please explain: See inspection report for details of system components.
10. Were monitoring wells properly constructed and located? Yes No N/A
If no, please explain:

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11. Are the monitoring well coordinates correct in BIMS? Yes No N/A
If no, please complete the following (expand table if necessary):
Monitoring Well Latitude Longitude
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12. Has a review of all self-monitoring data been conducted (e.g., DMR, NDMR, NDAR, GW)? Yes or No
Please summarize any findings resulting from this review: Ammonia limits were exceeded in March and April
2016, March 2018, May 2019, and May 2020; however ammonia has not been an issue in the past 6+
months. Additionally, TSS limits were exceeded in February 2016, August and October 2018, January
2019, and February and May 2020; however, TSS limits have not been an issue in the past 6+ months. No
violations have been issued to the facility since May 2020.
Provide input to help the permit writer evaluate any requests for reduced monitoring, if applicable.
13. Are there any permit changes needed in order to address ongoing BIMS violations? Yes or No
If yes, please explain: !!!!!
14. Check all that apply:
No compliance issues Current enforcement action(s) Currently under JOC
Notice(s) of violation Currently under SOC Currently under moratorium
Please explain and attach any documents that may help clarify answer/comments (i.e., NOV, NOD, etc.)
If the facility has had compliance problems during the permit cycle, please explain the status. Has the RO been
working with the Permittee? Is a solution underway or in place? The facility has had compliance issues during
the permit cycle as noted above, but have not had a limit violation since May 2020. Both primary clarifiers
are being used as EQ basins, and we believe this should be reevaluated by the facility. The facility staff are
aware that some system components are degrading and they are very interested in improving them. Their
plan is to buy a new RAS pump in FY 22, and they also hope to rehabilitate the offline aeration basin and
eventually tertiary filters. Solids management has greatly improved (sludge blankets are maintained at a
much lower level) and they are still fine tuning it. They have also ordered parts to replace the sweep arm
and drive unit in one of the secondary clarifiers.
Have all compliance dates/conditions in the existing permit been satisfied? Yes No N/A
If no, please explain:
15. Are there any issues related to compliance/enforcement that should be resolved before issuing this permit?
Yes No N/A
If yes, please explain:
16. Possible toxic impacts to surface waters: Chlorine can impact surface waters if not properly removed. No
issues reported with the dechlorination feed at the facility and no permit issues related to chlorine
residual.
17. Pretreatment Program (POTWs only): N/A IWS requested by 7/1/2021.

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IV. REGIONAL OFFICE RECOMMENDATIONS
1. Do you foresee any problems with issuance/renewal of this permit? Yes or No
If yes, please explain:
2. List any items that you would like the NPDES Unit or Non-Discharge Unit Central Office to obtain through an
additional information request:
Item Reason

3. List specific permit conditions recommended to be removed from the permit when issued:
Condition Reason

4. List specific special conditions or compliance schedules recommended to be included in the permit when issued:
Condition Reason

5. Recommendation: Hold, pending receipt and review of additional information by regional office
Hold, pending review of draft permit by regional office
Issue upon receipt of needed additional information
Issue
Deny (Please state reasons: )

6. Signature of report preparer:

Signature of assistant regional supervisor:

Date:

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V. ADDITIONAL REGIONAL STAFF REVIEW ITEMS
See inspection report from February 2021 for facility recommendations.

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