NC0025542_Environmental Assessment_20081027

NPDES DOCIMENT SCANNINL COVER SHEET
NPDES Permit:
NC0025542
Catawba WWTP
Document Type:
Permit Issuance
Wasteload Allocation
Authorization to Construct (AtC)
Permit Modification
Complete File - Historical
Report
Speculative Limits
Instream Assessment (67b)
Environmental Assessment (EA)
Permit
History
Document Date:
October 27, 2008
This document is pri:ited on reuse paper - igriore any
content on the reYerse side

Nowell, Jackie
From: Hannah Stallings [Hannah.Stallings© ncmail.net]
Sent: Monday, October 27, 2008 3:58 PM
To: 'Kevin Smith'
Cc: 'Jackie Nowell'; 'Pam Behm'; 'Allen Ratzlaff'; Linville, James R.
Subject: Re: City of Hickory -Catawba WWTP Upgrade EA
Kevin -
I have just flipped thru the EA you emailed this morning and have compared it to the March
2007 version. I find it a bit strange that only one paragraph (in section 4.6) has been
added after the length negotiations with USFWS and NCWRC. Looking thru the emails with USFWS,
all I see is mention of the erosion control rules, so I guess the language in the EA does
cover it. But I am used to more changes than this to a document after such lengthy talks
with agencies.
Looking at Ron Linville's April 19, 2007 comments, he specifically requests that "the EA be
amended or resubmitted to include specific local regulatory language about requirements that
are references as providing mitigation for anticipated growth in the sewer services area"
and that the EA "provide additional details about how local programs will evaluate and
mitigate for direct and indirect SCI impacts associated with the proposed new sewer service
areas." From my brief review of the document and it only having had one paragraph added to
the text, I am in doubt that NCWRC and probably USFWS would approve this. I would be much
more comfortable if they review the complete document prior to any issuance of a FNSI.
Also, all my prior comments of June 15, 2007 were not addressed:
* 6.12 still refers to water quality impacts from effluent as
cumulative impacts. These are direct impacts of the operation of
the expanded plant.
Also, just curious why Environmental Justice was addressed - that isn't required for SEPA
documents. Does Hickory anticipate receiving some type of Federal funding for this project?
A major concern is the speculative limits that were received on August 29, 2008. Speculative
limits are only provided for a 3 MGD discharge.
As the EA states, this is to be a phased project with both phases being covered in the EA and
the subsequent FNSI issued for this project.
However, ENSR only provided information necessary for determination of the 3 MGD discharge
and did not address the 1.5 speculative discharge limit request. Therefore, under the
current situation, the 1.5 MGD discharge will have to meet the limits issued for 3 MGD. If
you so desire, you may resubmit a request including the 1.5 MGD phase I discharge - it is
possible that the WWTP might have less stringent requirements at 1.5 than 3 MGD.
I did not do a detailed review of the EA (or EAA) that were submitted electronically to me
today because of the issues listed above.
And, as previously stated in our emails, I would prefer to have a formal statement of
concurrence (with whatever conditions) from the agency's themselves.
If you have any questions or concerns, please let me know.
Hannah
Smith, Kevin wrote:
> Hannah,
1

>
>
>
> The speculative limits were just now received because the NPDES unit
> required us complete a Water Quality Model of the Lyle Creek/Lake
> Norman area. A lot of time was also spent on deciding who was going
> to develop the model, us or them. We originally requested speculative
> limits in May of 2005. Nothing has changed the preliminary design.
> NPDES told us the limits that we would be looking at if we did not do
> a model, which is what we based the documents on. These limits were
> much stricter than the limits NPDES came back with after the model was
> done, so the design did not change..
>
>
>
> The EA itself does not contain anything about the speculative limits,
> however the EAA does. Both are attached. Please let me know if I
> need to add a section to the EA for the speculative limits.
>
>
>
> Thanks,
>
>
>
> Kevin Smith, PE
>
>
>
>
>
> HSMM AECOM
>
> T 864.597.0580 x4516 F 864.597.0583
>
> www.hsmm.aecom.com
>
>
>
>
>
> Original Message
> From: Hannah Stallings[mailto:[e-mail]]
> Sent: Friday, October 24, 2008 3:10 PM
> To: Smith, Kevin
> Subject: Re: City of Hickory -Catawba WWTP Upgrade EA
>
>
>
> Kevin -
>
> I apologize for having taken so long to get back to you. I have just
>
> given up on someone in the RO getting back to me on this one - I have
>
> attempted to contact someone several times and get no response.
>

> Getting spec. limits so late in the process troubles me a bit. Why
> was
>
> this done so late in the process? Has anything changed - flow,
> effluent
>
> parameters that will impact impacts of the discharge?
>
> I think it might be best to email me a copy of the EA with an
>
> explanation of why spec. limits were received so late.
>
> After I look this over, I will let you know what the next step is.
>
> As you said in your email, I will need formal response from agencies.
> I
>
> am afraid of what conditions/mitigation may not be included in the
>
> attached email.
>
> After I have looked over the emailed copy and discuss with you (and
>
> perhaps internally, also), I will let you know about getting copies to
>
> USFWS and NCWRC for their final review.
>
>
>
> Hannah
>
>
>
>
>
>
>
>
>
Hannah Stallings
SEPA Coordinator
DWQ - Planning Section
1617 Mail Service Center
Raleigh, NC 27699-1617
phone [phone]
fax [phone]

Hickory- Catawba WWTP
Residual Chlorine
7Q10 (CFS)
DESIGN FLOW (MGD)
DESIGN FLOW (CFS)
STREAM STD (UG/L)
UPS BACKGROUND LEVEL (l
IWC (%)
Allowable Concentration (ucy
Fecal Limit
Ratio of 1.0 :1
t 4.8
4.65
17.0
0
49.21
34.55
1,JA4
Ammonia as NH3
(summer)
7Q10 (CFS)
DESIGN FLOW (MGD)
DESIGN FLOW (CFS)
STREAM STD (MG/L)
UPS BACKGROUND LEVEL
IWC (%)
Allowable Concentration (m
Ammonia as NH3
(winter)
7010 (CFS)
200h00m1 DESIGN FLOW (MGD)
DESIGN FLOW (CFS)
STREAM STD (MG/L)
UPS BACKGROUND LEVEL
IWC (%)
Allowable Concentration (m
4.8
3
4.65
1.0
0.22
49.21
1.81
4.8
3
4.65
1.8
0.22
49.21
3.43
NC0025542
8/22/2008

Hickory- Catawba WWTP
Residual Chlorine
7Q10 (CFS)
DESIGN FLOW (MGD)
DESIGN FLOW (CFS)
STREAM STD (UG/L)
UPS BACKGROUND LEVEL (l
IWC (%)
Allowable Concentration (ugi
Fecal Limit
Ratio of 2.8 :1
Ammonia as NH3
(summer)
13 7Q10 (CFS)
3 DESIGN FLOW (MGD)
4.65 DESIGN FLOW (CFS)
17.0 STREAM STD (MG/L)
0 UPS BACKGROUND LEVEL
26.35 IWC (%)
64.53 Allowable Concentration (m
Ammonia as NH3
(winter)
7Q10 (CFS)
200/100m1 DESIGN FLOW (MGD)
DESIGN FLOW (CFS)
STREAM STD (MG/L)
UPS BACKGROUND LEVEL
IWC (%)
Allowable Concentration (m
13
3
4.65
1.0
0.22
26.35
3.18
19
3
4.65
1.8
0.22
19.66
8.26
NC0025542
8/22/2008

W A TFq Michael F. Easley
QG �A Governor
7 ©ENR William G. Ross, Jr., Secretary
= lV�w�v!� —r
North Carolina Department of Environment and Natural Resources
Alan W. Klimek, P.E., Director
Division of Water Quality
March 6, 2008
Kevin Smith, Project Engineer
HSMM
1460 John. B. White Blvd. Suite 1C
Spartanburg, South Carolina 29306
Subject: EAA Review
NPDES Permit NC0025542
Catawba WWTP
Catawba County
Dear Mr. Smith:
The Division of Water Quality (Division) has reviewed your Engineering Alternative Analysis (EAA) for the
City of Hickory Catawba WWTP expansion. The Division concurs with the conclusions and
recommendations of the EAA. The EAA you have submitted is sufficient to meet the Alternative Analysis
requirements for an expanded discharge.
The Division is currently reviewing the modeling information for the proposed discharge you have
provided. After the review is completed we will contact you to discuss the next step in the expansion
process. If you have any questions concerning this issue, please contact me at telephone number (919) 733-
5083, extension 594.
Sincerely,
/ Sergei Chernikov, Ph.D.
tY Environmental Engineer II
NPDES-West
cc: Central Files
NPDES Permit File
Mooresville Regional Office / Surface Water Protection
N. C. Division of Water Quality / NPDES Unit
1617 Mail Service Center, Raleigh, NC 27699-1617
Internet: h2o.enr.state.nc.us
Phone: [phone]
fax: [phone]
DENR Customer Service Center 1 800 623-7748

■
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■
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II. PROVIDE REASONABLE PROJECTIONS FOR POPULATIONS AND FLOW
A. RESIDENTIAL POPULATION PROJECTIONS
Dramatic growth is expected in areas surrounding Catawba's Town limits. The City of
Hickory is anticipating approximately 4,200 new residential and commercial connections from
planned developments in these surrounding areas. The planned developments will send their
sewer to the City of Hickory -Catawba WWTP. A map of the probable new service area for the
Town of Catawba showing the areas of future growth is shown in Exhibit II -A.
Table II -A — Projected Population, shows population projections for the Town of Catawba
through the year 2030. These projections are based on population projections for Catawba
County taken from the North Carolina State Demographics website. Table II -A also shows the
anticipated population within the drainage basin for the City of Hickory/Catawba system,
which is based on 4,200 anticipated residential and commercial connections. A letter from the
City of Hickory justifying the anticipated connections is included as Exhibit II-A-2
Table II -A
Projected Population
Estimated
Population
(2005)
Percent of
County
Population
Projected
Population
(2030)
Catawba County
149,416
Town of Catawba
730
Town of Catawba Existing Service Area
Future Development
Drainage Basin (Future Development
plus Existing Service Area)
680
200,880
0.49%
990
0.46%
914
28,770
29,684
Lok.0/1
S 1F2c 1('
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l'1�Fh ���'7 %�"t
■
ENGINEERING ALTERNATIVES ANALYSIS
CITY OF HICKORY, N.C.
CITY OF HICKORY-CATAWBA WWTP
PAGE 5 3.0-MGD UPGRADE

B. MUNICIPAL FLOW PROJECTIONS
1. CURRENT FLOW
From January to December 2004 Hickory billed residents in the Catawba service area for
an average of 0.047-MGD. Assuming a 10% consumptive loss, the expected wastewater
flow from residential and commercial users is 0.042-MGD, with 0.032-MGD residential
flow and 0.010-MGD commercial/industrial flow.
Influent flow to any wastewater treatment plant will include some amount of inflow and
infiltration. Using the water billing records supplied by the City of Hickory, average
expected flows and average measured plant flows were calculated. From these flow
calculations, average inflow/infiltration was calculated. As shown below, the total
current flow for the COH/C WWTP may be estimated at 0.043-MGD based on flow
records. The average daily plant flow as calculated in this manner will be used for all
future plant projections included in this document.
CURRENT CITY OF HICKORY-CATAWBA FLOWS (2004)
Average Daily Water Billing 0.047 MGD
90% Water Billing 0.042 MGD
Average Inflow/Infiltration 0.001 MGD
Total Average Daily Flow: 0.043 MGD
Infiltration, as defined by NCDENR's Construction Grants and Loans Section, is the
average daily flow of the three wettest consecutive months minus the expected flow.
Infiltration greater than 3,000 gallons per day per inch -mile (gpdim) is deemed
excessive by NCDENR. The Town of Catawba collection system consists of about 60
inch -miles of pipe. The average daily flows and the expected flows for the months of
September through November 2004 are given below.
FLOWS FOR SEPTEMBER — NOVEMBER 2004
Plant Average 0.042 MGD
Water Billing 0.047 MGD
ENGINEERING ALTERNATIVES ANALYSIS CITY OF HICKORY-CATAWBA WWTP
CITY OF HICKORY, N.C. PAGE 6 3.0-MGD UPGRADE
w
r
1
A
I
1
1
1

I
r
r
t
t
I
90% Water Billing 0.042 MGD
85% Water Billing 0.040 MGD
The infiltration based on a 15 percent consumptive loss is calculated as 39 gpdim, and
negligible assuming a 10 percent consumptive loss. The infiltration experienced in the
City of Hickory -Catawba collection system is not excessive as defined by NCDENR
Construction Grants and Loans Section.
Inflow is defined as water discharged into a sewerage system from such sources as, but
not limited to, roof leaders, drains from swamps or springs, manhole covers, cross -
connections from storm sewers, cooling -water discharges, surface run-off, and street
wash water. NCDENR's Construction Grants and Loans Section estimates inflow using
flow records following a one -inch rain event. The rain event selected for the analysis
must be preceded by at least five dry weather days. From September 2004 to July 2005,
two rain events were recorded by the City of Hickory that met these requirements.
These rain events are summarized in Table II-B-1.
NCDENR defines excessive inflow as non -industrial peak flows at the WWTP that
exceed 275 gpd per capita served. Based on this criterion, none of the rain events
included in the analysis resulted in excessive inflow.
Table II-B-1
Analysis of Inflow
Date
Rainfall (in)
Average Peak
Flow (MGD)
Gallons per
day per capita
09/08/04
4.5
0.157
231
04/04/05
1.1
0.026
38.2
2. FUTURE RESIDENTIAL FLOW
The initial wastewater flow used in future flow projection is assumed to be 0.043-MGD
as derived in Section II.B 1. As outlined by NCDENR, projected residential flows are
ENGINEERING ALTERNATIVES ANALYSIS
CITY OF HICKORY, N.C.
PAGE 7
CITY OF I-IICKORY-CATAWBA WWTP
3.0-MGD UPGRADE

based on 70 gpd per capita growth. The projected flows developed in this manner are
summarized in Table 'II-B-2.
3. FUTURE COMMERCIAL FLOW
The projected commercial growth is estimated at 0.45-MGD and is based on 15-gpd per
capita growth. Table II-B-2 below summarizes projected flows.
4. FUTURE INDUSTRIAL FLOW
Based on the guidance for Engineering Reports from the Clean Water State Revolving
Fund, a 10% industrial reserve, 0.25-MGD has been included into the flow projection.
5. FUTURE NON-EXCESSNE I/I •
Inflow and Infiltration are not included in the flow projection.
Table II-B-2
Projected Flows
Projected
Population
(2030)
Projected Residential
WW Flows
(70-gpd per capita)
Projected Commercial
WW Flows
(15-gpd per capita)
Proposed
Drainage Basin
29,684
2.08 MGD
0.45 MGD
Anticipated flows in the service area are based on the population projections summarized in
Table H-A. The projected flows attempt to account for industrial, residential, and commercial
growth within the service area across the twenty-year planning period.
Total flow forecasted includes residential flow, commercial flow, and a 10% industrial reserve
based on current flows. At the end of the twenty year planning period, the total projected
residential and commercial flow within the drainage basin is 2.5-MGD. With a 10% industrial
reserve built in, the total flow becomes 2.75-MGD. Based on this projection a plant capacity of
3-MGD willbe sufficient to handle the forecasted influent flow for the drainage basin.
ENGINEERING ALTERNATIVES ANALYSIS CITY OF HICKORY-CATAWBA WWTP
CITY OF HICKORY, N.C. PAGE 8 3.0-MGD UPGRADE

Connelly Springs
1-40
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ong View US 321
Hildebran
Conover
Burke County Catawba County
Catawba River Basin
Subbasin 32
Newton
12 Miles
NC 16
03050101140010
Horseford Creek
Lyle Creek
Catawba River Basin
Subbasin 32
Targeted Local
Watersheds
90020 and
40010
Horseford Creek and
Lyle Creek
0 Local Watershed Boundaries
' / Hydrography
Primary Roads
�•�'��•' County Boundaries
Municipal Boundaries
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Developed
Agriculture
Forest/Shrub/Marsh
Waterbodies

liv�T,Q Michael F. Easley
�O� QG ,Q►�� Governor
�\ 7 William G. Ross, Jr., Secretary
' r NCDENR North Carolina Department of Environment and Natural Resources
`< Alan W. Klimek, P.E., Director
Division of Water Quality
November 2, 2007
To: Hannah Stallings
Environmental Assessment Coordinator
Planning Section
From: Sergei Chernikov, Ph.D.
Environmental Engineer II
NPDES Unit
Re: City of Hickory — Expansion of the
Catawba Wastewater Treatment Plant
The NPDES-West has reviewed the City of Hickory's Environmental Assessment/Engineering
Alternative Analysis (EA/EAA) and has to object to the approval of the project. We have no
comments regarding EA portion of the document. However the EAA is inadequate, the projected
flow is not justified and appears extremely overestimated, all the available alternatives are not
fully evaluated. The consultant needs to provide appropriate documentation to justify projected
flow and that the EAA in it's current form can not be approved.
This document has been reviewed by NPDES on July 6, 2006 and comments were provided to
the consultants. However, the new document does not address previous problems and concerns.
The consultants also need to conduct a modeling before we can develop speculative limits for
this facility. The modeling is needed because proposed discharge is located in the cove of the
lake or the lake itself.
cc: Permit File
Central Files
N. C. Division of Water Quality / NPDES Unit
1617 Mail Service Center, Raleigh, NC 27699-1617
Internet: h2o.enr.state.nc.us
Phone: [phone]
fax: [phone]
DENR Customer Service Center: 1 800 623-7748

Catawba WWTP Expansion
Subject: Catawba WWTP Expansion
From: "Cibik. Steve" <[e-mail]>
Date: Thu, 21 Sep 2006 18:54:49 -0400
To: <[e-mail]>
Hey Jackie,
I apologize for asking this question, but I was driving when we spoke on Tuesday and thus was not able to
take any notes during our call. You mentioned the wasteload allocation study that was previously done for
Lyle Creek recommended limits for two parameters and related what those limits were. I cannot recall with
certainty what you told me, so please provide them again and forgive my short memory.
I did look at the existing Catawba River Basin Plans on the Basinwide Assessment Program's website. The
most recent (2004) does not mention limits for discharges, but I found the following in the 1999 plan:
»Lyle Creek Watershed Management Strategy
This watershed includes Lyle Creek, Huffman Branch, McLin Creek, Mull Creek, Hagan Fork and all
other Lyle Creek tributaries. In July 1988, a modeling study of the Lyle Creek watershed was
conducted to address an expansion request for the Conover Northeast. The model was used to
establish NPDES permit limits for new and expanding facilities in the Lyle Creek watershed. This
approach has been used since 1988. It was recommended that this strategy continue as part of the
Catawba Basinwide Plan.
Status of Progress
All new and expanding facilities receive BOD limits of 8 mg/I and NH3 limits of 2 mg/I to hold the load
of oxygen -consuming wastes constant.«<
Is this what you mentioned over the phone? I seemed to recall that they were both nutrient parameters (my
memory was that it was NH3 and TP). Is the 1988 study cited in the basin plan the wasteload allocation you
alluded to? Did you have any success in locating that? I'd like to get a copy if you do locate the study.
Thanks in advance for your response. Steve
Stephen J. Cibik
Principal Technical Specialist
ENSR
7041 Old Wake Forest Rd, Suite 103
Raleigh, NC 27616
[phone], x226
[phone] (fax)
scibikc ensr.aecom.com
www.ensr.aecom.com
1 of 1 9/22/2006 9:42 AM

Re: Hickory -Catawba WWTP
Subject: Re: Hickory -Catawba WWTP
From: Pam Behm <[e-mail]>
Date: Tue, 12 Sep 2006 10:11:21 -0400
To: Susan Wilson <[e-mail]>
CC: jackie Nowell <[e-mail]>
Hi Jackie and Susan -
Steve Cibik is calling me to setup this conference call to talk about the new spec
limits request. His number is 919-872-6600 x226. Per your email below, I am happy to
leave this one to you, but he is anxious to get some kind of response on this (I had a
voice mail from him yesterday and a phone call first thing this morning). Thanks.
Pam
Susan Wilson wrote:
hey - dont' recall getting it (doesn't mean i didn't!). If Jackie didn't run the
model for the higher flow, then it's not been done. Sergei was only reviewing the
EAA within the EA (and it had it's own set of problems!).
so....i'll let you and Jackie discuss first and see where things are at - but let's
do plan to have a discussion prior to any conf. call (and if there aren't issues
with nutrients there - maybe you can just leave that one to Jackie and me?).
Pam Behm wrote:
Hi Jackie -
I have some additional information on the Hickory -Catawba request. Apparently,
they sent a new spec limits request letter to Susan dated April 27, 2006
referencing the phased expansion (1.5 MGD in phase 1, 3.0 in phase 2). The
contractor mentioned that the phased expansion was discussed in a PER submitted
to the State on March 16, 2006. It has been reviewed by Sergei Chernikov and is
currently being reviewed by Hannah Stallings. So, I am not sure if Sergei ran
the Level B for this revised expansion request. They are still requesting to
have a conference call soon (i.e. the week of Sept. 11) to determine the steps
forward. Should we meet internally to make sure everyone is on the same page
first? Do we really need to have an involved conference call right now if we
all agree that a nutrient response model is not necessary? At this point, we
are fine with them not doing a nutrient response model, but we are concerned
with the potential DO impact, especially where the sag recovers.
Thanks,
Pam
*Susan A. Wilson, P.E.*
Supervisor, Western NPDES Program
(919) 733 - 5083, ext. 510
1617 Mail Service Center
Raleigh, NC 27699-1617
1 of 1 9/12/2006 10:15 AM

ENSR
AECOM
ENSR Consulting and Engineering (NC),Inc.
7041 Old Wake Forest Rd, Suite 103, Raleigh NC 27616-3013
T 919.872.6600 F 919.872.7996 www.ensr.aecom.com
August 10, 2006
Ms. Pamela Behm
Ms. Michelle Woolfolk
NC DENR Division of Water Quality, Planning Branch
Modeling and TMDL Unit
512 N. Salisbury St.
Raleigh, NC 27604
Transmitted by electronic mail to: [e-mail]
Michelle.Woolfolkancmail.net
Subject: Proposed Hickory Catawba WWTP Expansion Project
Dear Pamela and Michelle,
The City of Hickory NC is evaluating an expansion of the Catawba Wastewater Treatment Plant
(WWTP), considered a critical step in providing long-term treatment capacity for Hickory and its
surrounding areas. The Catawba WWTP is located on Lyle Creek approximately 0.6 mile upstream of its
confluence with the Catawba River (latitude 35° 42' 53" N, longitude 81° 04' 26.1" W). The Catawba
WWTP has a current design capacity of 0.225 million gallons day (MGD) and discharges into Lyle Creek
under NPDES permit No. NC0025542. The proposed expansion will occur in phases that will initially
increase discharge to 1.5 MGD and ultimately to 3.0 MGD. The objective of this summary is to obtain
regulatory input on design parameters to begin this process.
At the outset of this process in May of 2005, the City requested that the N.C. Division of Water Quality
(DWQ) provide speculative discharge limits for the expansion to support planning -level studies. Ms.
Susan Wilson of DWQ's NPDES Western Program responded in a letter dated October 10, 2005 stating
that speculative limits could not be provided at that time. The letter did indicate that "Based on the wide,
cove -like area of the receiving stream and the substantial increase in wasteflow", DWQ felt that
modeling for oxygen demand and nutrient effects would be required.
The referenced "cove -like" characterization is depicted in the U.S. Geological Survey (USGS) July 1986
topographic map for the area (Figure 1). However, aerial photographs of this segment of the creek
depict a narrow channel between the WWTP and the river (Figure 2). The "cove -like" area suggested
by the topographic map appears to be a wooded peninsula with a smaller, parallel creek to the north
that opens to the river. This was confirmed during a site reconnaissance performed by ENSR on April
25, 2006 to ground -truth the available imagery.
U.S. Fish & Wildlife Service National Wetland Inventory maps indicate that the majority of the "cove" on
the north side of Lyle Creek is actually forested wetland (PF01Ah)1, while the south side is shrub -scrub
wetland (PSS1Ah).2 Digital topographic data available from the USGS3 indicate that the peninsula has
1
Palustrine, Forested, Broad -Leaved Deciduous, Temporarily Flooded, Diked/Impounded
2 Palustrine, Scrub/Shrub, Broad -Leaved Deciduous, Temporarily Flooded, Diked/Impounded
3 http://nmviewogc.cr.usgs.gov/elevationResults.html

Ms. Pam Behm
Ms. Michelle Woolfolk
Page 2
an elevation up to 9 feet higher than the 761 foot full -pool elevation of Lake Norman and Lyle Creek.
Flood maps obtained from the North Carolina Flood Mapping Program indicate this peninsula lies within
the 100-year flood plain, suggesting that the presence of cove -like conditions would be relatively rare
and likely associated with high flow rates in the creek and river.
During our conference call on May 17, 2006 there was a consensus that nutrient modeling might not be
warranted if it was demonstrated that the segment of Lyle Creek from the WWTP discharge to its
confluence with the Catawba River was determined to have channel -like characteristics and not a cove
as depicted in the topographic map. We believe that typical conditions in this segment are
characterized by channelized flow and that cove -like conditions would only occur during high flow
periods and flood events. Nutrient modeling for the proposed increase in discharge capacity would
therefore not appear to be warranted.
ENSR requests that we schedule another conference call to discuss permitting the proposed expansion
project once you have had the opportunity to review this information. If your schedules permit we would
like to suggest August 23 to 25 as a potential window for the conference call.
Thank you in advance for your time in reviewing this material. If you have any questions please contact
Steve at 919.872.6600, extension 226.
Sincerely yours,
-44
Stephen J. Cibik
Ken Hickey
Principal Technical Specialist Water Resources Program Manager
Cc: Jonathan Hunt/HSMM
ENSR
AECOM

Catawba Wastewater Treatment Plant
HSMM
Catawba County, North Carolina
Image Source: USGS Topographic Quadrangle: Catawba, 1998
0 750 1,500 3,000 4,500 6,000
Feet
Figure Number
1
w
N
S
E
ENSR
7041 Old Wake Forest Rd
Suite103
Raleigh, NC 27616

Catawba Wastewater Treatment Plant
HSMM
Catawba County, North Carolina
Image Source: USGS DOQQ: Catawba (1998)
0 325 650 1,300 1,950 2,600
Feet
ENSR
7041 Old Wake Forest Rd
Suite103
Raleigh, NC 27616

Catawba Wastewater Treatment Plant
HSMM
Catawba County, North Carolina
Image Source: USGS DOQQ: Catawba (1998) and National Wetlands Inventory
0 325 650 1,300
1,950
2,600
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Figure Number
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7041 Old Wake Forest Rd
Suite103
Raleigh, NC 27616

pF W AT
r9 Michael F. Easley
OC\ QG �A Governor
fir\ ©`� William G. Ross, Jr., Secretary
NCDENR R North Carolina Department of Environment and Natural Resources
'< Alan W. Klimek, P.E., Director
Division of Water Quality
July 6, 2006
To: Alex Marks
Environmental Assessment Coordinator
Planning Section
From: Sergei Chemikov, Ph.D.
Environmental Engineer II
NPDES Unit
s,e,
Re: City of Hickory — Expansion of the
Catawba Wastewater Treatment Plant
The NPDES-West has reviewed the City of Hickory's Environmental Assessment/Engineering
Alternative Analysis (EA/EAA) and has to object to the approval of the project. We have no
comments regarding EA portion of the document. However the EAA is inadequate, the projected
flow is not justified and appears extremely overestimated, all the available altematives are not
fully evaluated. I have informed the consultant who prepared the document that they need to
provide appropriate documentation to justify projected flow and that the EAA in it's current form
can not be approved.
The consultants also need to conduct a modeling before we can develop speculative limits for
this facility. The modeling is needed because proposed discharge is located in the cove of the
lake or the lake itself.
cc: Permit File
Central Files
N. C. Division of Water Quality / NPDES Unit
1617 Mail Service Center, Raleigh, NC 27699-1617
Internet: h2o.enr.state.nc.us
Phone: [phone]
fax: [phone]
DENR Customer Service Center: 1 800 623-7748

HSMM
ARCHITECTS ENGINEERS PLANNERS
April 27, 2006
Ms. Susan. A. Wilson
NCDENR Division of Water Quality
Point Source Branch — Western Branch
1617 Mail Service Center
Raleigh, NC 27699-1617
Re: Request for Speculative Limits
Proposed WWTP Expansion and Renovation to 3.0 MGD
City of Hickory/Catawba WWTP
City of Hickory, NC
HSMM Commission No. 60709
Dear Ms. Wilson:
MAY - 4 2006
;ty
.. _ Li,;aNr.l♦
A letter requesting speculative effluent limits for the Hickory -Catawba WWTP was sent to
NPDES Western Unit on May 12, 2005. On October 10, 2005 a response was sent back to the
City of Hickory notifying them that speculative limits could not be provided at that time. The
letter mentioned that a more complex water quality model was recommended for this discharge,
and recommended the Water Quality Analysis Simulation Program (WASP6) be used to model
the Lyle Creek area for oxygen consuming parameters, such as BOD5, dissolved oxygen, and
ammonia, in addition to nutrients such as nitrogen and phosphorus. The letter suggests that
additional modeling needs to be performed due to the location of the discharge point into a
"covelike area of the receiving stream."
HSMM, on behalf of the City of Hickory, would like to request the department to issue
speculative limits for a new discharge of 3.0-mgd into Lake Norman. This location will be out
of the covelike area with the optimism that the more complex water quality model, as instructed
for the existing discharge location, can be avoided. Enclosed please find a topographic map
showing the location of the WWTP, the location of the existing discharge to Lyle Creek, and the
approximate proposed discharge into Lake Norman. The coordinates of the proposed discharge
are noted on the map as well.
Should you have any questions or require additional information, please feel free to contact us at
[phone].
Sincerely,
HSMM
Rich Anderson, P.E.
Copy to: Mr. Kevin Greer, P.E., City of Hickory; Mr. Jim Tindall, P.E. HSMM
Hayes, Seay, Mattern & Mattern, Inc. ARCHITECTS ENGINEERS PLANNERS
1460 John B. White, Sr., Boulevard Spartanburg, SC 29306 Tel.:[phone] Fax:[phone] www.hsmm.com