NC0026051_Comments_20220707

OURHAM Engineering and
COUNTY
GEO Environmental Services RECEIVED
Utilities Division
JUL 0 7 2022
June 16, 2022
RETURN RECEIPT REQUESTED NCDEQ/DWR/NPDES
CERTIFIED MAIL #70042510000506123389
Mr. Gary Perlmutter
NCDEQ/DWR
NPDES Municipal Permitting Unit
1617 Mail Service Center
Raleigh,North Carolina 27699-1617
Re: Comments on Draft NPDES Permit NC0026051
Dear Mr. Perlmutter:
Thank you for the opportunity to comment on the draft NPDES permit with cover letter dated May
12, 2022, which was emailed for review on May 20, 2022. We have reviewed the draft NPDES
permit, and our comments are listed below.
1. After reviewing Effluent Limitations and Monitoring Requirements A.(1.), Durham
County is requesting the following:
a. Bis(2-ethylhexyl) phthalate be removed from the permit or at least be limited to
quarterly monitoring for two years so that eight samples can be collected and then
NCDWR can evaluate whether there is a reasonable potential. Bis(2-ethylhexyl)
phthalate hits are typically due to sampler and/or lab contamination. Out of three
results, the last two were less than detect which could lead one to believe the first
was a contaminated sample.
b. 1,4-Dioxane be removed from the permit as the three values used were influent
results, but NCDWR used these results as if they were effluent results to suggest
reasonable potential to exceed a water quality standard that has not been adopted.
NCDWR also used one half on the detection limit for the values that were less than
when this method should only be used for pretreatment determinations. Per the
DMR guidelines, less than values are considered zero which would have put the
average under the allowable effluent concentration.
c. PFAS only required to be monitored annually. From the last four analyses
completed, Triangle Wastewater Treatment Plant (TWWTP) was below the
allowable effluent concentration of 145.27 ng/L. Durham County staff has
surveyed all industrial users, Significant and Local, and have notified them that
PFAS is not allowed to be discharged. Page 15 of the Fact Sheet states that more
results are needed for evaluation, and it is believed that annual sampling will
5926 NC Highway 55 East,Durham,North Carolina 27713
[phone] I fax[phone] I dconc.gov
Equal Employment/Affirmative Action Employer

DURHAM Engineering and
COUNTY
EEO Environmental Services
�,,,t) Utilities Division
provide that information. Also, there is no information to suggest reasonable
potential to exceed a water quality standard that has not been adopted.
2. Durham County is requesting that the in-stream monitoring requirements A.(2.)be revised
to remove the nutrient monitoring. Currently,NCDWR has a Memorandum of Agreement
with the Upper Cape Fear River Basin Association which samples downstream of the
TWWTP, Station B367000 and upstream of the TWWTP, Station B3300000 for nutrients.
Durham County believes this is redundant sampling and is an inefficient use of resources.
Durham County may contest any stream sampling beyond the minimum required by 15A
NCAC 02B .0500. Please note Durham County has in-house certifications for the tests
required by 15A NCAC 02B .0500. The additional tests required in the draft permit
requires the use of outside labs and considerable expense. Please recognize that Durham
County voluntary submitted to the early application of the Jordan Lake nutrient limits, and
as such believes it is most appropriate to use ratepayer's remittances for the treatment of
wastewater and not for redundant stream monitoring.
Furthermore, the In-stream Waste Concentration (IWC) is 100%, which caps our toxicity
sampling requirements at 90%, and the 7Q10 flow is 0 cubic feet per second (cfs) for
Northeast Creek making the creek makeup mainly our effluent discharge. Durham County
is already required to monitor nutrients on the effluent. Again,this is redundant monitoring
and inefficient use of resources.
3. On page 7, the next to last paragraph states, "If the permittee monitors any pollutant more
frequently than required by this permit, the results of such monitoring shall be included in
the calculation&reporting of the data submitted on the DMR and all AT Form submitted."
This should be modified to state "monitors any effluent pollutants more frequently than
required" per 15A NCAC 02B .0506 as there is no regulation requiring reporting for
additional influent or other location data not specified in the NPDES permit.
4. Without the requested changes the cost of monitoring will increase by nineteen percent
(19%) based on current rates. Based on the new rates anticipated beginning July 1, 2022
and adding in additional surcharge costs due to the inflation in gas and supplies,the overall
amount will increase between twenty-five to thirty percent (25-30%) in fiscal year 2023.
5. The following typos need to be addressed.
a. On page 3, this should be A.(1.) and not A.(7.).
b. On page 5, this should be A.(2.) and not A.(8.).
c. On page 10 under A.(6.), the first paragraph should be (a.) and not (c.), and the
second paragraph should be (b.) and not (d.).
d. On pages 11-12 under A.(7.), the lettering is off showing (c.) through (h.) and
should be (a.) through (f.).
5926 NC Highway 55 East,Durham,North Carolina 27713
[phone] j Fax[phone] dconc.gov
Equal Employment/Affirmative Action Employer

DURHAM Engineering and
COUNTY
BE0 ' Environmental Services
Utilities Division
e. On page 12, under A.(8.), the first paragraph should be (a.) and not (c.), and the
second paragraph should be (b.) and not(d.).
f. On page 14,this should be A.(13.) and not A.(5.).
We trust that these comments will be thoroughly considered. If you have any questions or need
any clarification,please contact me at(919) 560-9034.
Sincerely,
Stephanie A. Brixey
Deputy Director of E&ES/POTW Director
cc: Michael Montebello,NCDWR NPDES Municipal Permitting Staff Supervisor
Jay Gibson, PE, General Manager
5926 NC Highway 55 East,Durham,North Catalina 27713
[phone] I Fax[phone] ( dcom:.gov
Equal Employment/Affirmative Action Employer