NC0069841_Correspondence_20240418 (4)

Baker, Caroline D
From: Bennett, Lucas <[e-mail]>
Sent: Thursday, April 18, 2024 3:37 PM
To: Tuvia, Ori A
Cc: Parker, Michael D.; Tommerdahl, Christy
Subject: Re: [External] ATC Application Question
CAUTION: External email. Do not click links or open attachments unless verified. Report suspicious emails with the Report Message
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Afternoon Ori,
Thanks for reaching out directly and giving us the opportunity to clarify. Here are some responses, and we can
gather more information if you would like:
Peaking Factor
• The Crooked Creek WRF has a 3.0 million gallon Flow Equalization basin which limits the peak flow through
the treatment facilities to 5.0 MGD.
• The Flow EQ system was designed by HDR and construction was completed in year 2019. The record
drawings from the project included a hydraulic profile which noted a peak process flow rate of 5.0 MGD.
With a plant rated flow of 1.9 MGD, this equates to a peaking factor of 2.63.
� EL. 651.75
EL. 654.06 EL. 653.50
EL. 651.05
TOP OF WALL
TOP OF TANK
60.00 EL. 655.50
EL. 652.67
INV. EL. 650.63
EL. 641.19
50.00
18'�
(0 5 mgd)
mmk
24so
% EL. 639.57
INV. EL. 647.E
-
/ (0 5 mgd)
TOP OF SLAB
TOP OF SLAB GRADE EL.
m
II q EL. 642.25-
30.00
EL. 624.50
EL. 624.50 631.00
GRADE EL.
CREENING GRIT
EXISTING OXIDATION GRADE EL.
624.20
RUCTURE REMOVAL
DITCHES 524.00
20.00
14-0
12" TO INFLUENT
PUMP STATION
10.00
16" Ilk EL. 619.83 EL
VIA MH #2107A
30" INV. EL. 605.69
Lo
EL. 599.44
00
24" INV. EL. 605.44
INFLUENT INFLUENT
DIVERSION
PUMP
BOX STATION
HYDRAULIC PROFILE NOI
1. ALL ELEVATIONS BAS
OF 8.0 MGD UNLESS
HYDRAULIC PROFILE
• In 2019, we (Hazen) performed a process evaluation Technical Memorandum that utilized these flow rates
and provided process recommendations (including replacing the existing UV Disinfection system). This
1

memorandum included data on the historical plant flow rates, shown below. This illustrates that the WRF
was operating well below the peak flow rate of 5.0 MGD, even before the Flow EQ system was completed.
4. Historical Data
Historical data from January 11, 2015 through May 31 n, 2018 were summarized and reviewed. Figure 4-
1 compares the daily and 30-day moving average flow to the monthly final effluent permit limit. Table 4-
1 summarizes the annual average (AA), maximum month (MM), maximum seven-day (7-Day), and
maximum day flow (MD) flows from January 2015 through May 2018,
Figure 4-1: Daily Effluent Flow, 30-day Moving Average, and Average Month Permit Limit
4.5
4.0
3.5
3.0
rn
2.5
E
2.0
1.5
1.0
0.5
0.0
Jan-15 Jul-15 Jan-16
—Monthly Average Permit Limit
UV Facility Freeboard
Jul-16 Jan-17 Jul-17 Jan-18 Jul-18
• Effluent Plant Flow —30-Day Moving Average
• Using the peak flow of 5.0 MGD, we performed a hydraulic analysis to ensure adequate freeboard through
the new UV facility.
• The UV equipment manufacturer, Trojan Technologies, has confirmed numerous times that the maximum
headloss through the banks will be 0.13-feet at the peak flow rate of 5 MGD. This is illustrated in the
hydraulic profile shown in our drawings, with additional headloss (0.16-feet) included for conservatism, to
reflect headlosses through the concrete UV channel itself.
• This results in 1.89-feet of freeboard.
PEI

640
635
630
16' SCE INV EL 628.30 S
625
620
615
610
605
600
Thankyou!
Lucas Bennett, PE
Principal Engineer I Hazen and Sawyer
9101 Southern Pine Blvd, Suite 250, Charlotte, NC 28273
704-941-6051 (work) 1 678-936-0799 (mobile)
The nnett(�Phaze nandsawyer.com I haze nandsawyer.com
From: Tuvia, Ori A <[e-mail]>
Sent: Thursday, April 18, 2024 1:56 PM
CONDITION I FLOW
PEAK FLOW 1 5.0 MOD
L
0.00 WATER SURFACE 6 PEAK FLOW
0 00 WATER SURFACE Q RATED FLOW
ELEVATION 0 PEAK DESIGN FLOW
24' PE INV EL 618.2
20'PE INV EL 6135
NOTES
I ELEVATIONS SHOWN FOR THE EFFLUENT PUMP STATIO
FROM UV AND LAB ADDITIONS PROJECT, 2D03.
2 ELEVATIONS FOR WEIRS LOCATED ATTHE CASCADE AE
EFFLUENT FILTERS WERE CONFIRMED BY SURVEY_
3. ELEVATIONS SHOW USING NOVO 29 DATUM.
3

To: Bennett, Lucas <Iben [e-mail]>
Cc: Parker, Michael D. <[e-mail]>; Tommerdahl, Christy <[e-mail]>
Subject: RE: [External] ATC Application Question
Good afternoon Lucas,
Looking over the proposed design, could you please provide some more information regarding the freeboard for the UV
system and the ability to meet 12in of freeboard as well as what peaking factor was determined to use?
Sincerely,
Ori Tuvia
Environmental Engineer III
NC DEQ / Division of Water Resources/ Permitting
610 East Center Avenue
Mooresville, NC 28115
Direct Line: [phone] Fax: [phone]
Ori.tuvia(D-deq.nc.gov
Email correspondence to and from this address is subject to the
North Carolina Public Records Law and may be disclosed to third parties.
From: Bennett, Lucas <[e-mail]>
Sent: Wednesday, April 17, 2024 3:20 PM
To: Tuvia, Ori A <[e-mail]>
Cc: Parker, Michael D. <[e-mail]>; Tommerdahl, Christy <[e-mail]>
Subject: Re: [External] ATC Application Question
CAUTION: External email. Do not click links or open attachments unless verified. Report suspicious emails with the Report Message
button located on your Outlook menu bar on the Home tab.
Ori,
Sorry about that. Here is a new folder on Google Drive that includes the files - hopefully it will work better.
https://drive.google.com/drive/folders/1 t1 GONRMyF19oNmvLS5CcBa2h8bmU_14D?usp=sharing
Thanks,
Lucas Bennett, PE
Principal Engineer I Hazen and Sawyer
9101 Southern Pine Blvd, Suite 250, Charlotte, NC 28273
704-941-6051 (work) 1 678-936-0799 (mobile)
Ibennett(o)hazenandsawyer.com I haze nandsawyer.com
From: Tuvia, Ori A <[e-mail]>
Sent: Wednesday, April 17, 2024 3:01 PM

To: Bennett, Lucas <Iben [e-mail]>
Cc: Parker, Michael D. <[e-mail]>; Tommerdahl, Christy<[e-mail]>
Subject: RE: [External] ATC Application Question
Hi Lucas,
It says it failed
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Error code: PR -CONNECT -RESET -ERROR
• The page you are trying to view cannot be shown because the authenticity c
verified.
Please contact the website owners to inform them of this problem.
Learn more...
Could you send me another way to download it
Thank you,
Ori Tuvia
Environmental Engineer III
NC DEQ / Division of Water Resources/ Permitting
610 East Center Avenue
Mooresville, NC 28115
Direct Line: [phone] Fax: [phone]
Ori.tuviaCa)-deg. nc.gov
-5::�'Nothing Compares]
Email correspondence to and from this address is subject to the
North Carolina Public Records Law and may be disclosed to third parties.
5

From: Bennett, Lucas <[e-mail]>
Sent: Wednesday, April 17, 2024 1:45 PM
To: Tuvia, Ori A <[e-mail]>
Cc: Parker, Michael D. <[e-mail]>; Tommerdahl, Christy <[e-mail]>
Subject: Re: [External] ATC Application Question
CAUTION: External email. Do not click links or open attachments unless verified. Report suspicious emails with the Report Message
button located on your Outlook menu bar on the Home tab.
Sure thing, the files are located in this Dropboxfolder.
https://www.d ropbox.com/scl/fo/wptty4znzfnxpb85p7t8e/ALBOCRVFLad KNAMokBeBWDs?rlkey=1 fwszghcmzd u n
pedu2z1 w4biy&st=kezxgxey&d1=0
Thanks,
Lucas Bennett, PE
Principal Engineer I Hazen and Sawyer
9101 Southern Pine Blvd, Suite 250, Charlotte, NC 28273
704-941-6051 (work) 1 678-936-0799 (mobile)
Ibennett(Oazenandsawyer.com I haze nandsawyer.com
From: Tuvia, Ori A <[e-mail]>
Sent: Wednesday, April 17, 2024 1:38 PM
To: Bennett, Lucas <[e-mail]>
Cc: Parker, Michael D. <[e-mail]>; Tommerdahl, Christy <[e-mail]>
Subject: RE: [External] ATC Application Question
You don't often get email from ori.tuvia(@deq.nc.gov. Learn why this is important
Could you please also send me a copy in an email or link to download it.
Looking forward to it
Sincerely,
Ori Tuvia
Environmental Engineer III
NC DEQ / Division of Water Resources/ Permitting
610 East Center Avenue
Mooresville, NC 28115
Direct Line: [phone] Fax: [phone]
Ori.tuvia(a-)-deg. nc.gov
It -��Nothing Compares]
Email correspondence to and from this address is subject to the

North Carolina Public Records Law and may be disclosed to third parties.
From: Bennett, Lucas <[e-mail]>
Sent: Wednesday, April 17, 2024 1:32 PM
To: Tuvia, Ori A <[e-mail]>
Cc: Parker, Michael D. <[e-mail]>; Tommerdahl, Christy <[e-mail]>
Subject: Re: [External] ATC Application Question
CAUTION: External email. Do not click links or open attachments unless verified. Report suspicious emails with the Report Message
button located on your Outlook menu bar on the Home tab.
Good afternoon Ori,
We have shipped the Authorization to Construct application to you for this project (Crooked Creek WRF UV
Disinfection Project) in three separate packages as described below. Please let us know if you have any questions!
Package 1: Application packet, engineering specifications, USB flash drive with digital files
Package 2: Engineering plans
Package 3 (letter): Check for $1,000
Thanks,
Lucas Bennett, PE
Principal Engineer I Hazen and Sawyer
9101 Southern Pine Blvd, Suite 250, Charlotte, NC 28273
704-941-6051 (work) 1 678-936-0799 (mobile)
Ibennetl:6�hazenandsawyer.com I hazenandsawyer.com
From: Tommerdahl, Christy <[e-mail]>
Sent: Wednesday, April 3, 2024 8:59 AM
To: Tuvia, Ori A <[e-mail]>
Cc: Bennett, Lucas <Iben [e-mail]>
Subject: RE: [External] ATC Application Question
Thank you for your quick response.
From: Tuvia, Ori A <[e-mail]>
Sent: Wednesday, April 3, 2024 7:05 AM
To: Tommerdahl, Christy <[e-mail]>
Cc: Bennett, Lucas <Iben [e-mail]>
Subject: RE: [External] ATC Application Question
Caution! External email —think before you click
Hi Christy,
Yes that is correct.
Sincerely,

Ori Tuvia
Environmental Engineer III
NC DEQ / Division of Water Resources/ Permitting
610 East Center Avenue
Mooresville, NC 28115
Direct Line: [phone] Fax: [phone]
Ori.tuvia(a-)-deg. nc.gov
-75-'-*�Nothing Compares.]
Email correspondence to and from this address is subject to the
North Carolina Public Records Law and may be disclosed to third parties.
From: Tommerdahl, Christy <[e-mail]>
Sent: Tuesday, April 2, 2024 4:28 PM
To: Tuvia, Ori A <[e-mail]>
Cc: Bennett, Lucas <[e-mail]>
Subject: [External] ATC Application Question
You don't often get email from [e-mail]. Learn why this is important
CAUTION: External email. Do not click links or open attachments unless verified. Report suspicious emails with the Report Message
button located on your Outlook menu bar on the Home tab.
Hi Ori,
I hope this email finds you well. I wanted to ask you a question on the ATC application prior to submitting for a project
on behalf of Union County. The project for the Crooked Creek WWTP will include a replacement of the existing UV
disinfection system with a new UV system. Section 4.B of the application requires basis of design information for various
parameters. We wanted to confirm that we only need to fill out the basis of design for the parameters that impact the
disinfection system (Fecal Coliform and TSS). Can "N/A" be listed for the other parameters in the table since they were
not used in the design of the new UV system?

13. WASTEWATER TREATMENT FACILITY DESIGN INFORMATION — COMPLETE FOR NE
EXPANDING FACILITIES AND FOR TREATMENT PROCESS MODIFICATIONS
Hare all of the requirements of 15 NQAC 021-L 0100: 15A NCAC 02T, North Carolina General Statute 133-3,1�
Carolina Gmeral Statute 143-215.1, and Division of Water Resources Minimum Design Criteaia for NPDES Ric
Treatment Facilities been met by the proposed design and specifications? ® Yes or ❑ Rio_ If no, prop ide jus#ii
why the requirements are not met, consistenoxith 15A NCAC 02T _0105(n):
2_ Prcnidee-the design influent and efIIumt characteristics that are used as the basis for the project design and the T,
permit limits for the folloxving parameters:
Project Basis of Design
Influent
Design Influent
Design Influent
Concentration
Concentration
Load
- Current
(A -lust be
(Must be
Annual
supported by
supported by
Design Effluent
Average (past
Engineering
Engineering
Concentration andfor
N TDES
12 months) if
Calculations
Calculations
Load
(wont]
Parameter
Available
rSection 3.
Section 3.
Ammonia Nitrogen
N/A mg,-L Summer
2-0 mi
3-
NIA mg+L
NIA mg/L
N/A lb. da}F
N/A mg L Winter
4-0 rr.
Biochemical
N/A mg'L Summer
5_0 m#
Oxygen Demand
N/A mgJL
NIA mgJL
WA lbiday
(BOD5)
N-A mg;L Winter
10.0 n
Fecal Colifarm
< 2.00 per 100 mL
2001
Nitrate + Nitrite
Nitrogen (NO3-N +
N/A mglL
N,
NO:.-
Tv#al Kj eldahl
NIA L
Nitrogen
QUA mg1
N,
Total Nitrogen
N.-'A lb/year
VA mg.'L
N.,Tc
al Phosphorus
M mg/L
NIA mg/L
N/A 1biday
N.-A 1b:' ear
Tc al Suspended
■ mgAL
mglL
4,000 lb.ic ay.
5 mg 1
3
Solids (TSS)
Thank you,
Christy Tommerdahl, PE
Associate I Hazen and Sawyer
620 Green Valley Rd., Suite 101, Greensboro, NC 27408
336-478-3372 (direct) 1 336-292-7490 (main)
ctommerdahl6a�hazenandsawyer.comI haze nandsawyer.com

Email correspondence to and from this address may be subject to the North Carolina Public Records Law and may be disclosed to third parties by an authorized
state official.
10