WQ0019755_Additional Information Request #2_20220705

July 5, 2022
PHILIP M. COOKE - MANAGER
JPC UTILITIES LLC
POST OFFICE BOX 345
OAK RIDGE, NORTH CAROLINA 27310
Subject: Application No. WQ0019755
Additional Information Request
Oak Ridge Commons WWTP
Reclaimed Water Generation,
Dedicated Utilization, and
Wastewater Irrigation System
Guilford County
Dear Mr. Cooke:
Division of Water Resources’ Central and Regional staff has reviewed the application package
received December 22, 2021 and subsequent additional information received April 20, 2022. However,
additional information is required before the review may be completed. Please address the items on the
attached pages no later than the close of business on August 4, 2022.
Please be aware that you are responsible for meeting all requirements set forth in North Carolina
rules and regulations. Any oversights that occurred in the review of the subject application package are
still the Applicant’s responsibility. In addition, any omissions made in responding to the outstanding items
in Sections A through E, or failure to provide the additional information on or before the above requested
date may result in your application being returned as incomplete pursuant to 15A NCAC 02T .0107(e)(2).

Please reference the subject application number when providing the requested information. All
revised and/or additional documentation shall be signed, sealed and dated (where needed), with an
electronic response submitted to my attention at: https://edocs.deq.nc.gov/Forms/NonDischarge-Branch-
Submittal-Form-Ver2.

If you have any questions regarding this request, please contact me at [phone] or
[e-mail]. Thank you for your cooperation.
Sincerely,
Lauren Raup-Plummer, PE, Engineer III
Division of Water Resources
cc: Winston-Salem Regional Office, Water Quality Regional Operations Section (Electronic Copy)
John Phillips, PE – Diehl & Phillips, PA (Electronic Copy)
Laserfiche File (Electronic Copy)
Mr. Philip M. Cooke
July 5, 2022
Page 2 of 3

A. Response Letter:
1. Within Response A.1, a discussion of solids overloading within granular filters is provided;
however, this discussion does not mention that there are numerous technologies available to remove
or reduce solids within the influent flows to allow for effective filter treatment. Additionally, the
response indicated that the Regional Office directed the Permittee to submit a permit modification
(this application) to the Central Office. The Regional Office does not have the authority to approve
modifications. This "operational aid" in the form of an overflow bypass allows partially treated
wastewater to be discharged onto the land surface and is in violation of the 15A NCAC 02U rules.
The overflow from the tertiary filter influent trough to the tablet chlorinator inlet trough cannot be
permitted and should be removed. Please revise the application submittal accordingly.
2. Within the response for Items D.1 and D.2, there were several statements made that require further
clarification. Please provide additional information regarding the following:
a. The provided justification for a second mudwell discharge pipe diverting backwash water
directly into the sludge holding tank appears to be sidestepping the question posed in the
previous Additional Information Request. This response states that the sludge holding tanks
were designed and permitted to accept waste solids from the treatment process. However, if
the connection of the mudwell pumps to the sludge holding tank was added post-design, then
no, the sludge holding tank was not originally designed and permitted to accept that discharge
and its associated flow composition directly. By discharging the backwash water directly into
the sludge holding tank, the benefits of flow equalization are negated. Additionally, the
mudwell discharge pipe is only entering the sludge holding tank located at Plan South on Sheet
2 which implies that the backwash flow is not being evenly distributed across the sludge
holding tank volume. Please provide additional information regarding the design and
operational parameters of the affected sludge holding tank and demonstrate that the individual
tank is adequately sized to receive the filter backwash water from the mudwell. Please note
operational differences, if any, between the sludge holding tank receiving filter backwash water
and the sludge holding tank operating as designed and permitted.
b. In Response D.1 the paragraph concerning the 6,000 gallon per day (GPD) wastewater
treatment system states that the only flow going into this plant is the periodic discharge of the
filter backwash water from the 30,000 GPD reclaimed water treatment system. Has the gravity
collection system that is upstream of the septic tank been abandoned, or is the doghouse
manhole depicted on Sheet 2 designed so that only peak flow conditions result in flow through
the wastewater treatment system’s inlet pipe? The hydraulic profile on Sheet 5 depicts an
manhole upstream with an invert elevation of 915.70.
c. To reiterate in Comment A.1 of this letter, Response D.2 is insufficient. The overflow from
the tertiary influent filter trough to the tablet chlorinator inlet trough cannot be permitted and
should be removed. Please revise the Engineering Plans accordingly and resubmit those pages
to meet the requirements of 15A NCAC 02U .0201(c). Revised plan sheets shall be signed,
sealed, and dated by a North Carolina licensed Professional Engineer in good standing.
3. Response E.2. for the calculations appears to contradict itself. The first paragraph discusses that
the only flow received by the 6,000 gpd wastewater treatment plant is the filter backwash water.
The second paragraph discusses that a force main is present from the originally permitted design
that directs influent wastewater from the flow equalization basin to the 6,000 gpd wastewater
treatment plant. Within the previous response (Response D.1) it was indicated that the diversion
Mr. Philip M. Cooke
July 5, 2022
Page 3 of 3
was necessary to prevent high levels in the flow equalization tank; however, this issue was
accounted for in the original design described in Paragraph 2 of Response E.2 by allowing increased
flows into the flow equalization tank to be pumped to the 6,000 GPD facility. The response further
discusses that the effluent sample testing results were uneven. Complete quarterly sampling data
was not provided, and it is unclear what the upper and lower limits for the effluent characteristics
were based on the averaged data. Please provide the complete dataset used to determine that the
wastewater treatment system is adequately sized to treat a singular wastewater influent consisting
of filter backwash water as described.
4. Response H.2 indicates that the operator does not have the ability to track flows between the
reclaimed water system and the wastewater treatment system. How does the operator ensure that
the diverted flows don’t exceed 6,000 GPD? With regards to the loading of the sludge holding
tank, how are the operational differences between the two sludge holding tanks being tracked or
otherwise managed?
5. Response H.3 indicates that there were operational concerns with increased solids loading in the
wastewater system’s recirculation tank. Have any other operational changes been required, beyond
raising the pumps, to ensure compliance of the 6,000 GPD wastewater irrigation system while
operating with the unpermitted modifications?
B. Engineering Plans:
1. Revised plan sheets were not provided for the removal of the unpermitted overflow piping. Please
provide revised engineering plan sheets meeting the requirements of 15A NCAC 02U .0201(c).
C. Engineering Calculations:
1. Please provide the current storage capacity (in days) for the two sludge holding tanks. These tanks
receive different flows based on the described modifications, therefore; separate calculations for
each tank are necessary to better understand the operations of the facility. Please note, the provided
engineering calculations shall be signed, sealed, and dated by a North Carolina licensed
Professional Engineer.
D. Operation & Maintenance Plan:
1. The Operation & Maintenance Plan (O&M Plan) for the facility is a separate document from the
Engineering Plans mentioned in Response F.1. Please provide an updated O&M Plan meeting the
requirements of 15A NCAC 02U .0801 and 15A NCAC 02T .0507 for our review.
E. Specifications:
1. Please provide specifications for the removal of the overflow piping from the tertiary influent filter
trough to the tablet chlorinator inlet trough. Specifications shall meet the requirements of 15A
NCAC 02U .0201(c).