NCG140000_DEQ Response to Flow Measurement Comments_20220608

Georgoulias, Bethany
From: Carson, Brittany
Sent: Wednesday, June 29, 2022 9:24 AM
To: Mark Cramer; Smith, Danny
Cc: Georgoulias, Bethany
Subject: RE: [External] RE: Comments Regarding Draft General Permit NCG140000
Good morning Mark,
We are still on target to renew the General Permit NCG140000 on July 15Y 2022.
As for the continuous flow rate requirement, our stance remains unchanged as we follow water quality standards set
down by 15A NCAC 02B. The specific rule can be found in 02B .0505.
15A NCAC 0211.0505 MONITORING REQUIREMENTS
(a) General_ Every person subject to this Section ("permittee") shall establish, operate, and maintain a monitoring
program consistent with its National Pollutant Discharge Elimination System (NPDES) Permit or as otherwise
required by the Director to characterize its wastestrcams and receiving waters, evaluate treatment performance, and
determine compliance with permit conditions and applicable water quality standards.
(b) Wastewater and Stream Flow Nlcasurem,cnt.
(1) Wastewater Flows.
(A) Every pmmdttce shall install, operate, and maintain continuous flow measuring devices
with recording or totalizing capabilities for each wastewater discharge, whether treated or
untreated, fbr which monitoring and reporting requirements arc specified in its permit;
except as provided in Part (C) of this Subparagraph-
(B) The permirtce shall install appropriate flow measurement devices consistent with
approved engineering and scientific practices to ensure the accuracy and reliability of
measurements of the volume of monitored discharges. Devices selected shall be capable
of measuring flows with a maximum deviation of less than 10 percent from true
discharge volumes. Flow measurement devices and their locations shall be subject to
approval by the Director prior to their installation, in accordance with these requirements
and 15A NCAC 02H .0138.
(C) On a case-by­casc basis. the Director may approve the use of alternative flow
measurement or flow control methods if such methods are reliable and sufl`icicntly
accurate to meet the aims of Paragraph (a) of this Rulc,
(D) Flow measurement devices shall be accurately calibrated at a minimum of once per year
and maintained to ensure that the accuracy of the measurements is consistent with the
accepted capability of that type of device. Records of flow measurement device
calibration shall be kept on file by the permitter far a period of at least three years_ At a
minimum, these records shall include the date of flow measurement device calibration
and name of the person performing the calibration;
It is worth noting that pump curves and pump logs may be used to calculate daily flow rate as referred below in the
Draft NCG140000.

G-Z Parameters and Limitations
[a) Wastewater discharges shall not exceed the effluent limitations provided in Table 6.
(b) The permittee shall collect and analyze grab samples of wastewater effluent for pH, TSS,
and Turbidity at each wastewater outfall.
[c) Grab samples shall be analyzed within 15 minutes for pH.
[d) Permittees discharging wastewater to receiving waters classified as HQ, UMW, SA, SB,
Tr or PKA shall also collect and analyze grab samples for Settleable Solids.
[e) Daily flow rate shall be recorded by a continuous flaw measurement instrument.
Alternatively, pump curves and pump Ings maybe used to calculate the daily flow rate.
Co Effluent limitations for wastewater discharges shall be in accordance with Table 6 below.
Thank you,
Brittany Carson
General Industrial Stormwater Permit Coordinator
Stormwater Program, Division of Energy, Mineral, and Land Resources
N.C. Department of Environmental Quality
Phone: [phone]
From: Mark Cramer <[e-mail]>
Sent: Wednesday, June 29, 2022 9:06 AM
To: Smith, Danny <[e-mail]>
Cc: Carson, Brittany <[e-mail]>; Georgoulias, Bethany <[e-mail]>
Subject: [External] RE: Comments Regarding Draft General Permit NCG140000
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What is the status of the NCG140000 renewal? Can DEQ provide more specific guidance on the continuous flow
monitoring requirement?
Mark Cramer, P.E. - Senior Engineer
The El Group, Inc.
Environmental, Health and Safety Solutions. TM
Direct: 919.459.5229
Mobile: [phone]
www.eil.com
From: Mark Cramer
Sent: Tuesday, June 7, 2022 11:28 AM
To: [e-mail]
Cc: Carson, Brittany <[e-mail]>
Subject: Comments Regarding Draft General Permit NCG140000
Danny— In addition to deletion of the Section B-8 BMP inspections at least every seven (7) calendar days that Brittany
Carson indicated was mistakenly added to the draft permit for NCG140000 (see email below), I would request that the
DEQ consider not adding the new Part G monitoring requirement of G-2(e) stating, "Daily flow rate shall be recorded by
a continuous flow measurement instrument. Alternatively, pump curves and pump logs may be used to calculate the

daily flow rate." Many concrete plants are designed such that ditches/ponds and other BMPs contain comingled
stormwater and the allowed process wastewaters (vehicle and equipment cleaning, wetting raw material stockpiles,
mixing drum cleanout) onsite and only discharge intermittently. Installing continuous flow meters creates a significant
expense and challenge to collect flow data that will not improve water quality ($16K capital quote I am aware of for a
single discharge point at one facility). This flow data will not facilitate stormwater meeting benchmarks or process
wastewaters meeting discharge limits.
Mark Cramer, P.E. - Senior Engineer
The El Group, Inc.
Environmental, Health and Safety Solutions. TM
Direct: 919.459.5229
Mobile: [phone]
www.eil.com
From: Carson, Brittany <[e-mail]>
Sent: Wednesday, May 18, 2022 10:23 AM
To: Mark Cramer <[e-mail]>
Subject: RE: [External] NCG140000 Inspections
Good morning Mark,
Thank you for pointing that out. That section (B-8) was mistakenly pulled into the draft NCG14. The 7 day BMP
inspections exist in the newly renewed NCG020000 (mining). The NCG02 and NCG14 share many similar aspects but that
one should not have been transferred. The BMP inspection requirements do not substantially change with the NCG14
renewal.
I will ensure it is removed from the NCG14 permit, thank you again for your comments.
Brittany Carson
General Industrial Stormwater Permit Coordinator
Stormwater Program, Division of Energy, Mineral, and Land Resources
N.C. Department of Environmental Quality
Phone: [phone]
From: Mark Cramer <[e-mail]>
Sent: Wednesday, May 18, 2022 6:53 AM
To: Carson, Brittany <[e-mail]>
Cc: Mike Walker <[e-mail]>
Subject: [External] NCG140000 Inspections
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In reviewing the Draft General Permit NCG140000 NPDES Permit to Discharge Stormwater from Concrete Plants, I see
there is a new BMP Inspection requirement for BMPs to be inspected and documented every seven (7) calendar days
(Section B-8). However, Section B-12 still also has the requirement for quarterly inspections. Although they read a little
different, they are basically looking at the same things, and this does not make sense to me. If the DEQ desires to
increase the frequency of these facility inspections to every seven days from the previous semi-annual, I can understand
that, but wouldn't this basically cover the quarterly. Is this a carry-over from using the template from other General
Permits, or does the DEQ really intend for these to be separate inspections documented separately? If separate, can the
DEQ please provide additional guidance for what the differences are that applicants should be checking and
documenting?

Your assistance is greatly appreciated.
Mark Cramer, P.E. - Senior Engineer
The El Group, Inc.
Environmental, Health and Safety Solutions. TM
Direct: 919.459.5229
Mobile: [phone]
www.eil.com
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