NC0069841_staff comments_20190628

Hill, David A
From:
Hill, David A
Sent:
Friday, June 28, 2019 9:18 AM
To:
Basinger, Corey
Cc:
Grzyb, Julie; Behm, Pamela
Subject:
RE: [External] Assimilation Capacity for Discharge of the Grassy Branch WRF
Hi Corey,
The NPDES permitting unit is unable to determine speculative limits for expansion of the Grassy Branch WWTP. The
facility was permitted with its current BOD= 5, Ammonia-N= 2 limits by rule 15A NCAC 02B .0206(d)(1) for flows where
7Q10=0 but 30Q2 >0 with no modeling done to determine assimilative capacity. This appears to have been done as a
regionalization effort in an effort to capture the waste flow by closing three smaller package plants serving schools in the
area, making it a BPJ call. There are three additional NPDES discharges in the Crooked Creek watershed, NC0035041-
Hemby Acres WWTP at 0.3 MGD, NC0069842-Crooked Creek#2 WWTP at 1.9 MGD, and NC0088838-Radiator Specialty
at 0.09 MGD. Crooked Creek #2 requested speculative limits for possible expansion in 2008, but NPDES permitting was
unable to provide speculative limits and determined that the Level B model we use was not applicable for the instream
conditions at that facility.
If Grassy Branch wishes to pursue expansion, then they will need to provide the Division with a QUAL2K model or
equivalent that considers the effects of all the interacting discharges in that watershed and ultimate assimilative
capacity in the Rocky River. They will need to consult with Pam Behm's group in the Modeling and Assessment Branch
for model plan approval before they begin. Otherwise they will have to consider other alternatives to direct discharge.
Radiator Specialty does not currently monitor for any oxygen -consuming waste parameters, but I assume chemical
oxygen demand may be an issue in any modeling efforts.
Please contact me if you have any further questions.
Sincerely,
David Hill
Environmental Specialist If
NC DEQ / Division of Water Resources / Water Quality Permitting
NPDES Complex Permitting, Wastewater Branch
919 707-3612 office
919 707 9000 main office
david.hill(d)ncdenr.gov
Physical Address: 512 North Salisbury St., Raleigh, NC, 27604
Mailing Address: 1617 Mail Service Center, Raleigh, NC, 27699-1617
Email correspondence to and from this address is subject to the
North Carolina Public Records Law and may be disclosed to third parties.
From: Basinger, Corey
Sent: Tuesday, June 25, 2019 9:03 AM
To: Hill, David A <[e-mail]>
Subject: FW: [External] Assimilation Capacity for Discharge of the Grassy Branch WRF
Hi David,

Hope all is well with you.
As you will see from the email chain below, one of MRO's facilities (Grassy Branch WWTP NC0085812, Union Co) will be
applying for an SOC in the very near term. They are hopeful that they can expand the facility from 50,000 gpd to
120,000 gpd. This proposed flow increase will obviously require an assessment of the assimilative capacity of the
receiving stream. The results of this assessment will determine the path forward with negotiating the SOC.
What is an estimated time frame that you feel will be required to complete this assessment?
If you would like to discuss, my direct number is 704-235-2194.
Thanks,
Corey
W. Corey Basinger
Regional Supervisor
Mooresville Regional Office
Water Quality Regional Operations Section
NCDEQ — Division of Water Resources
Chairman
Water Pollution Control System Operators Certification Commission
[phone] office
[phone] office direct line
Email: corey.basinger(ZDncdenr.aov
610 E. Center Avenue
Suite 301
Mooresville, NC 28115
From: Denard, Derek
Sent: Monday, June 24, 2019 4:51 PM
To: Basinger, Corey <[e-mail]>
Cc: Scheller, Roberto <[e-mail]>; Andy Neff <and .neffco.union.nc.us>
Subject: RE: [External] Assimilation Capacity for Discharge of the Grassy Branch WRF
Corey,
An increase in flow and speculative limits will require modeling. They need to contact David Hill with the Complex
Permitting Unit to discuss what is -needed. His contact information is: David. Hillft ncdenr. ov and phone [phone]
Derek C Denard
Environmental Specialist
Compliance & Expedited Permitting Unit
N.C. Division of Water Resources
N.C. Department of Environmental Quality
919 707 3618 office
919 707 9000 main DWR
derek.denardC(z ncdenr.gov
N. C. Division of Water Resources
Water Quality Permitting Section - NPDES
1617 Mail Service Center
Raleigh, NC 27699-1617

Email correspondence to and from this address is subject to the
North Carolina Public Records Law and may be disclosed to third parties.
From: Basinger, Corey
Sent: Monday, June 24, 2019 3:32 PM
To: Denard, Derek <[e-mail]>
Cc: Scheller, Roberto <[e-mail]>; Andy Neff <[e-mail]. nc.us>
Subject: FW: [External] Assimilation Capacity for Discharge of the Grassy Branch WRF
Derek,
Please review the email below from Andy Neff with Union County. This request is in reference to the Grassy Branch
WWTP (NC0085812).
They are preparing to submit an SOC request and we have already had our pre -application meeting.
The answers to the two (2) bulleted items in Andy's email will assist them, and the Division, in moving forward with
much needed upgrades.
If you need to discuss, please contact Roberto or me.
Thanks in advance for your prompt efforts on this one.
Corey
W. Corey Basinger
Regional Supervisor
Mooresville Regional Office
Water Quality Regional Operations Section
NCDEQ — Division of Water Resources
Chairman
Water Pollution Control System Operators Certification Commission
[phone] office
[phone] office direct line
Email: corev.basinaeramcdenr.aov
610 E. Center Avenue
Suite 301
Mooresville, NC 28115
From: Andy Neff[mailto:[e-mail]
Sent: Monday, June 24, 2019 3:10 PM
To: Basinger, Corey <[e-mail]>
Cc: Hyong Yi <[e-mail]>; Josh Brooks <Josh. Brooks@ unioncount nc. ov>; Bart Farmer
<[e-mail]>; Danny Smith<[e-mail]>; John Shutak
<[e-mail]>; 'Sadler, Mary' <msadler hazenandsaw er.com>; 'Parker, Michael D.'
<[e-mail]>; Struve, lames N. <[e-mail]>
Subject: [External] Assimilation Capacity for Discharge of the Grassy Branch WRF

Corey,
We had a meeting today to discuss potential solutions and submission of an SOC to the Department with our Engineer,
Hazen. The solution we may be proposing involves expansion of the Grassy Branch WRF from 50,000 gpd to 120,000
gpd with the addition of a 70,000 gpd treatment train. Based on our conversation this afternoon, request you review
the assimilative capacity of the receiving stream to determine:
• If it can accept a 70,000 increase in discharge and,
Are there any loading limits we should be aware of with this increase in capacity (speculative limits)?
We would like to know this prior to submission of the SOC should there be an issue. Thanks,
Andy
Andrew Neff, P.E.
Water and Wastewater Division Director
Union County Public Works
4600 Goldmine Rd
Monroe, NC 28112
T 704.296.4215
andv.neff(Wco.union.nc.us
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