NC0063096_Environmental Assessment_20110819

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Environmental Assessment
Town of Holly Springs
Wastewater Treatment Facility Expansion and
Discharge Relocation
Wake County, North Carolina
Lead Agency Contact:
Ms. Hannah Stallings
SEPA Coordinator
NC Department of Environment and Natural Resources
Division of Water Quality — Planning Section
1617 Mail Service Center
Raleigh, NC 27699-1617
[phone]
Prepared For:
THE TOWN
dolly
Springs
NOR III CAROL. INA
Stephanie L. Sudan, P.E.
PO Box 8
Holly Springs, NC 27540
919-557-3938
AUGUST 2011
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Project Engineer: s%,9F� L s`V`���•`
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Davis -Martin -Powell & Associates
6415 Old Plank Road
High Point, NC 27265
336-886-4821
Prepared By:
CAROLINA ECOSYSTEMS, INC.
3040 NC 42 West
Clayton, NC 27520
919-606-1065

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Table of Contents
Section
Title
Page
I
Executive Summary
iii
A
Project Description
1
A.1
Existing Systems and Conditions
1
A.2
Proposed Project Description
3
A.3
Project Service Area
3
B
Need
4
C
Alternatives Analysis
5
C.1
No Action
5
C.2
Optimum Operation of Existing Facilities
6
C.3
Harnett County Regional Interconnection
6
CA
Treatment at the Western Wake WRF
6
C.5
Wastewater Treatment Facility Expansion
7
C.5.1
Cape Fear River Discharge
8
C.5.2
Lower Utley Creek Discharge (Preferred Alternative)
9
C.5.3
Land Application
11
C.5.4
Wastewater Reuse
11
D
Existing Environmental Characteristics of Project Area
13
D.1
Topography
13
D.2
Soils
13
D.3
Land Use
14
DA
Wetlands
15
D.5
Prime or Unique Farmlands
15
D.6
Public Lands, Scenic, Recreational, & State Natural Areas
15
D.7
Areas of Archaeological or Historical Value
16
D.8
Air Quality
16
D.9
Noise Levels
16
D.10
Water Resources (Surface Water & Groundwater)
16
D.11
Forest Resources
18
D.12
Shellfish or Fish and Their Habitats
19
D.13
Wildlife and Natural Vegetation
19
E
Predicted Environmental Effects of the Project
21
E.1
Topography
21
E.2
Soils
21
E.3
Land Use
21
EA
Wetlands
22
E.5
Prime or Unique Farmlands
22
E.6
Public Lands, Scenic, Recreational, & State Natural Areas
22
E.7
Areas of Archaeological or Historical Value
23
E.8
Air Quality
23
E.9
Noise Levels
23
E.10
Water Resources (Surface Water & Groundwater)
23
E.11
Forest Resources
24
E.12
Shellfish or Fish and Their Habitats
24
E.13
Wildlife and Natural Vegetation
25
E.14
Introduction of Toxic Substances
25
Town of Holly Springs
i
Environmental
Assessment August 2011

I
F Mitigative Measures 27
G References 29
H Exhibits 31
List of Figures (Exhibit H)
Figure 1:
Vicinity Map
Figure 2:
Site Plan
Figure 3:
Soil Survey
Figure 4:
USGS Quad Map
Figure 5:
Wetland Map
List of Tables
Page
Table 1
Current Discharge Limits
1
Table 2
Cape Fear River Discharge Limits
9
Table 3
Lower Utley Creek Discharge Limits
10
Table 4
Alternative Discharge Location Summary
12
Table 5
Soil Types in Study Area
14
Table 6
Federally Protected Species Listed for Wake Co, NC
20
List of Appendices (Included electronically on attached disk)
Appendix A:
Town Land Use & Infrastructure Maps
Appendix B:
2007 Finding of No Significant Impact & EA
Appendix C:
2010 Record of Decision & EIS
Appendix D:
Engineering Alternatives Analysis
Appendix E:
Secondary & Cumulative Impacts Master Mitigation Plan
Appendix F:
Wetland and Stream Data Forms
Appendix G:
Archaeological/Historical Resource Review
Appendix H:
Aquatic Mussel Survey Results
Town of Holly Springs ii
Environmental Assessment August 2011
r^1
e"k)

of
Executive Summary
The Town of Holly Springs is evaluating alternatives for the existing Utley Creek Water
Reclamation Facility (UCWRF). In support of this evaluation a detailed Engineering
Alternatives Analysis and this Environmental Assessment were performed. Both
wastewater treatment and discharge alternatives were assessed. For treatment
alternatives, the EA examines upgrading the Utley Creek WRF, optimizing treatment at
the facility, and regional treatment alternatives.
Upgrading the Utley Creek WRF is the preferred treatment alternative; other alternatives
were eliminated from consideration based on not meeting the project purpose and need or
having higher environmental impacts and costs. Two practical discharge location
alternatives met the project purpose and need: a surface water discharge to the Cape Fear
River, via pump station and force main to the Western Wake Regional Water
Reclamation Facility (WWRWRF), or a surface water discharge to Lower Utley Creek,
via a gravity effluent pipe from the UCWRF. The Cape Fear River discharge alternative
for Holly Springs was included in the Final Environmental Impact Statement (FEIS) and
Record of Decision (ROD) for the WWRWRF and is evaluated in this EA for comparison
purposes.
The preferred discharge alternative is to discharge into Lower Utley Creek, a Harris Lake
tributary, just below Greentree Reservoir. This alternative includes the construction of
r� multiple treatment process improvements on the UCWRF site to increase the treatment
capacity (and subsequent discharge) to 8 mgd and improve the efficiency of nutrient
removal, and construction of an approximate 11,700 linear foot outfall line and cascade
aerator at the discharge site within the potential future pool elevation of Harris Lake. The
need for the capacity was justified in the WWRWRF FEIS and ROD.
The preferred discharge alternative was chosen based on an evaluation of all potential
environmental impacts. The preferred alternative would have less impact than the Cape
Fear River alternative on soils, land use, prime farmland, water resources, and aquatic
habitat. The Cape Fear River alternative would have less impact on forests and wildlife
habitat. The two alternative discharge locations would have similar effects on wetlands
and streams. As the Lower Utley Creek Discharge would have similar or less
environmental impact than the Cape Fear River Discharge and is under half the cost, the
Lower Utley Creek Discharge was chosen as the preferred alternative.
Minimal direct impacts would result from the proposed project. The new treatment
components would be located on already disturbed areas within the boundaries of the
current UCWRF facility. Minor impacts to soils, land use, wetlands, streams, forest land,
and wildlife habitat would occur from construction of the effluent line (Table 1).
Due to the negligible amount of environmental impact associated with the proposed
project, few mitigative measures are proposed. If the US Army Corps of Engineers or
NC Division of Water Quality require compensatory mitigation for wetland and stream
r4"N impacts, it will be provided through payment to a mitigation bank. Other construction
Town of Holly Springs iii
Environmental Assessment August 2011

N
e%�
measures, including sediment and erosion control devices and standard permit conditions
for wetland and stream crossings, would be implemented during construction to protect
water quality and aquatic habitats. Construction would be limited to weekdays and
daylight hours unless absolutely necessary, and fuel will be contained in designated
refueling stations along the construction corridor.
Table 1: Alternative Discharge Location Summary
Cape Fear Discharge*
Lower Utley Creek. Discharge
Cost
$47 million
$20 million
permanent change
No permanent change
-TopographyNo
Soils
34 ac. disturbed (most roadside)
15.3 ac. disturbed
Land Use
30.9 ac. Easement
10.3 ac. Easement
Wetlands
0.13 (0.03permanent) ac.
0.10 (0.06permanent) ac.
Streams
6 crossings:
- 3 intermittent
- 3 perennial
7 crossings:
- 3 intermittent
- 4 perennial
Prime/Unique
Farmland
15.7 ac.
3.7 ac.
Public Areas
Gamelands — minor impact
Gamelands — minor impact
Archaeological/
Historical
None
None
Air Quality
Pump station & generator
Temporary (construction)
Noise Levels
Temporary (construction)
Temporary (construction)
Water Resources
Eliminates loading and reduces
flow in Utley Creek; minor transfer
of water out of Harris Lake
watershed
Eliminates loading and reduces
flow in upper Utley Creek;
continued supply to Harris Lake
watershed
Forests
2.4 ac.
13.7 ac.
Shellfish/fish
Reduction of habitat in all of Utley
Creek; improved water quality in
impounded stream areas
Reduction of habitat in upper
Utley Creek; improved water
quality in impounded stream
areas
Wildlife/
Vegetation
2.4 ac. habitat
13.7 ac. Habitat
Toxic Substances
1 None anticipated
None anticipated
*Numerical data from WWRWRF FEIS.
Town of Holly Springs iv
Environmental Assessment August 2011

A
Section A: Project Description
A.1 Existing Systems and Conditions
The Town of Holly Springs (Town) operates the Utley Creek Water Reclamation Facility
(UCWRF) on the southwest side of the Town (Figure 1). Following wastewater
treatment the UCWRF discharges into Utley Creek, which flows to the White Oak Creek
arm of Harris Lake. The UCWRF serves the entire Town service area depicted in the
Town's Land Use Map in Appendix A. Current average daily flows from the UCWRF
are approximately 1.33 million gallons per day (mgd). The current permitted discharge
from the UCWRF is 2.4 mgd (Table 1), as previously documented in an Environmental
Assessment (EA) and a Finding of No Significant Impact (FNSI) issued in February 2007
(Appendix B). An 8 mgd discharge from the UCWRF to the Cape Fear River was
approved through the Western Wake Regional Water Reclamation Facility (WWRWRF)
Final Environmental Impact Statement (FEIS) and Record of Decision (ROD) in 2010
(Appendix C) described in more detail below. This EA analyzes the expansion of the
UCWRF discharge from 2.4 to 8 mgd and the relocation of the proposed 8 mgd discharge
to the lower portion of Utley Creek within the Harris Lake watershed downstream of the
currently permitted 2.4 mgd discharge location.
Table 1: Current Discharge Limits
Parameter
Utley Creek
(Current)
Flow, mgd
2.4
BOD5, mg/L
5.0 / 10.0
Total Suspended Solids, mg/L
30.0
Ammonia Nitrogen, mg/L
1.0 / 2.0
Total Nitrogen, lbs/day
120
Total Nitrogen, mg/L
----
Total Phosphorus, lb/day
10.0
Total Phosphorus, mg/L
0.5
Orthophosphate, mg/L
----
Fecal Coliform, #/100 mL
200
Dissolved Oxygen, mg/L
6.0
pH, units
6-9
'Dual limits are summer / winter season
2 Current permit limits are expressed in lb/year and based on 6 mg/L TN
3 Current permit limits are expressed in lb/year and based on 0.5 mg/L TP
Town of Holly Springs Page 1
Environmental Assessment August 2011

ra
The 2007 FNSI (Appendix B) included a condition requiring the Town to move its
UCWRF discharge out of Utley Creek to the proposed Western Wake Regional Water
Reclamation Facility (WWRWRF). This condition was included because of North
Carolina Division of Water Quality (NCDWQ) concerns regarding increased nutrient
loading on small impoundments in Utley Creek. While Utley Creek is not listed as
impaired, these concerns have been expressed in past Basinwide Water Quality planning
documents that referenced a fish kill in July 1996 and algal blooms in Thomas Mill Pond
during the same time period, and algal blooms in Greentree Reservoir during 1997. Since
that time, major infrastructure improvements have been accomplished including two
treatment technology upgrades, improved plant management, and improved stormwater
and development controls.
The WWRWRF is the result of a regional wastewater management partnership approach
that began in 2000 with the strong encouragement of NCDWQ and originally included
the Town of Holly Springs along with the Towns of Apex, Cary, and Morrisville. After
an extensive facilities alternatives evaluation, the proposed WWRWRF includes a new
Water Reclamation Facility in New Hill that will treat wastewater from Apex, Cary,
Morrisville, and the Wake County portion of the Research Triangle Park (RTP South).
This facility will discharge treated effluent to the Cape Fear River at a location below
Buckhorn Dam. Holly Springs' participation was limited to the effluent conveyance
component of the regional project and would have continued to treat its wastewater at its
existing UCWRF, pumping the treated wastewater to the effluent pumping station at the
WWRWRF site in New Hill (Figure 1). A combined discharge line would then convey �•.,
the treated effluent to the Cape Fear River. The US Army Corps of Engineers' (USAGE)
FEIS for the WWRWRF found that the least environmentally damaging practical
alternative was the proposed WWRWRF, which included the Cape Fear River discharge.
A ROD for the WWRWRF FEIS was issued on July 21, 2010 (Appendix C). This FEIS
and ROD justified a flow of 8 mgd from the Town of Holly Springs in the year 2030.
Among alternatives studied within the FEIS was a WWRWRF discharge into Harris
Lake. Initially, the NCDWQ discouraged a discharge to Harris Lake. However, after
Progress Energy's nuclear plant expansion plans became public and a water quality
model was developed, a Harris Lake discharge became a primary alternative for the
WWRWRF. It was then determined that this location would require either a new or
modified interbasin transfer (IBT) certificate for the Towns of Apex, Cary, Morrisville,
and RTP South. The IBT modification review and approval process takes a minimum of
four years and would not meet the schedule of the WWRWRF commitments and the
purpose and need for that project. Therefore the Harris Lake alternative was eliminated
from further consideration by the Apex, Cary, and Morrisville partners. The USACE
FEIS states that "if the Town receives speculative limits to discharge directly or
indirectly to Harris Lake, it may choose to pursue a discharge to the lake."
Effluent from the UCWRF does not require an IBT to be discharged into Harris Lake in
the Cape Fear River Basin because the Town's water supply also is from this basin via
Harnett County. Therefore, this alternative is still a practical option for the Town of
Holly Springs to consider, in addition to other wastewater discharge alternatives such as
Town of Holly Springs Page 2
Environmental Assessment August 2011

the shared outfall line with the WWRWRF. The Town has performed this EA and
.accompanying EAA to consider the environmental effects, impacts on the human
environment, and costs of an increase in permitted capacity to 8 mgd discharge on Lower
Utley Creek versus other alternatives.
A.2 Proposed Project Description
Based on the alternatives analysis and results of studies performed for this EA, the
preferred alternative is to expand the permitted capacity of the UCWRF to 8 mgd and to
discharge the effluent into Lower Utley Creek below both Thomas Mill Pond and
Greentree Reservoir. Speculative limits for this location were issued by NCDWQ for an
8 mgd discharge on June 24, 2011. It is proposed that UCWRF plant improvements to
enhance the level of treatment would be constructed within existing disturbed areas on
the plant site (Section C.2). The proposed improvements would enhance nutrient
removal beyond the treatment process upgrades for the expansion project completed in
2010. Additionally, the proposed project components can treat and convey up to the 8
mgd capacity justified by the USACE in a ROD for the WWRWRF (Appendix Q. A
description of the proposed treatment process improvements is included in Section C.2.
An approximate 11,700 linear foot 48-inch effluent line would be constructed parallel to
Utley Creek to a discharge point just below Greentree Reservoir and within the potential
future pool elevation of Harris Lake (Figure 2). The outfall would terminate with a bank
discharge through a cascade aerator into Lower Utley Creek. This pipeline is sized to
convey peak effluent flows. The project would disturb 15.3 acres of land associated with
improvements in the UCWRF treatment process and construction of gravity effluent line
and a cascade aerator.
A.3 Project Service Area
The project involves relocation of the discharge of treated wastewater effluent from the
UCWRF treatment plant, which serves the entire Town sewer collection system
(Appendix A). No new service area would result from this project, as no new expansion
of the collection system is associated with the proposed project.
The Town's current population is approximately 24,661 per the preliminary 2010 Census
data. This is a 168% increase over the 2000 Census. This number is projected to
increase to over 71,000 by 2030. This information has been documented in the EAA
(Appendix D). Current and future land use within the Town's planning jurisdiction is
shown in Appendix A. The Town's land use plan is updated regularly as a component of
the Town's "Vision Holly Springs" Comprehensive Plan. The proposed effluent line lies
partly within Holly Springs and partly within Wake County jurisdiction. Zoning within
the project area is part Research Technology, but primarily R-30 (Holly Springs) or R-80
(Wake County).
Town of Holly Springs Page 3
Environmental Assessment August 2011

Section B: Need
The purpose of the proposed project is to meet existing and forecasted demand in the
Holly Springs service area and to comply with the requirements of the FNSI for the Town
to relocate its discharge due to NCDWQ's nutrient concerns in the small impoundments
on Utley Creek. The need for the proposed project is to provide wastewater treatment
capacity for the projected population growth in the Town's service area and to meet
speculative limits required for the relocated discharge. The Town provides public
wastewater service to its residents within its service area as shown on the Long Range
Wastewater Capital Improvements Plan (Appendix A). The Town has experienced rapid
growth in the last several decades, which is documented in the EA and FNSI (Appendix
B), the WWRWRF FEIS and ROD (Appendix C), and the EAA (Appendix D). Flows
from the UCWRF are anticipated to be approximately 4.8 mgd in 2015, escalating to 6.27
mgd in 2020, and to 8 mgd in 2030. The need to expand the UCWRF to handle the
projected treatment capacity has been previously justified in the 2007 EA and FNSI and
the WWRWRF FEIS and ROD.
Since the initial water quality concerns in 1996 and 1997 that led to NCDWQ's
requirement to relocate the discharge, there have been several changes to the UCWRF
and to Utley Creek that warrant a re-evaluation of the Town's discharge alternatives. The
UCWRF plant was expanded from a package treatment -type plant with very limited
treatment technology first to a 1.5 mgd three stage oxidation ditch treatment facility in
1999, then most recently upgraded again to a five stage biological nutrient removal
treatment system capable of meeting the 2004 Speculative Cape Fear River nutrient
discharge requirements. Both upgrades have been constructed to the limits of technology
reasonably available at the time the upgrades were approved. Also since that time,
Thomas Mill Pond has been partially breached and the weir system on Greentree
Reservoir has not been maintained as operational (flashboards are removed). Finally, the
Town has enacted a series of progressive development restrictions to minimize the
environmental effects of development. This effort is documented in the Town's
Secondary and Cumulative Impacts Master Mitigation Plan (SCIMMP) (Appendix E),
which is updated biennially. These measures include stream buffers in the Cape Fear
basin, coordination with other agency approvals prior to issuing construction approval,
sedimentation and erosion control requirements for smaller sites, and implementation of a
Phase II NPDES Municipal Separate Storm Sewer System (MS4) Program.
The State has issued speculative limits for discharges to Harris Lake and to a proposed
location on Utley Creek below Greentree Reservoir. Therefore, a Harris Lake/Lower
Utley Creek discharge was deemed to be a practical alternative, and evaluation of a full
range of alternatives and environmental impacts associated with the UCWRF discharge
was performed.
Town of Holly Springs Page 4
Environmental Assessment August 2011

Section C: Alternatives Analysis
Alternatives for the management and discharge of the Town's wastewater have been
evaluated in the 201 Facilities Plan EA/FNSI and the WWRWRF FEIS/ROD and are also
addressed in this document. Alternatives are evaluated on two levels: Wastewater
Management followed by Discharge Location of the preferred management option.
Several Wastewater Management Options were evaluated including No Action, Optimum
Operation of Existing Facilities, Regional Solutions, and the UCWRF Expansion and
Discharge Relocation.
C.1 Management Option A: "No Action"
The "no action" alternative is not considered feasible because it would not meet
immediate and projected needs for wastewater treatment capacity. The Town has
invested nearly $29 million in the upgrade and expansion of its wastewater treatment
facilities over the past 5 years to expand and upgrade the treatment facilities' capacity to
6 mgd. With no further improvements, the usable capacity would be limited to the
current NPDES discharge of 2.4 mgd, plus any reclaimed water usage.
"No Action" would require future development to be served by private wastewater
treatment facilities or septic tanks. Use of private wastewater treatment facilities is not
considered acceptable because such facilities historically have resulted in poor quality
effluent being discharged to receiving streams. Streams with sufficient assimilative
capacity for new wastewater discharges are also unlikely to be available in the Town's
service area. Septic tanks are also not acceptable on an extensive scale because many of
the soils in Wake County have moderate to severe restrictions for septic tanks due to low
soil permeability. In addition, projected development is expected to be at or near urban
densities throughout the portion of the service area within the Town's growth areas and
the adjoining county residential and commercial service areas. Septic fields would
require larger lot sizes and additional land clearing for future development, as well as
increase potential ground water quality issues.
The lack of available wastewater capacity will also limit industrial development potential
which in turn could have a negative economic impact on the Town's growth and
development. Economic development has recently slowed, but is beginning to rebound.
Competition for industry and the jobs industries provide is likely to be high as
municipalities and the State of North Carolina try to recover from the current economic
downturn. A lack of sufficient wastewater capacity could result in lost economic
development opportunities.
This alternative will not be considered any further, as it does not meet the purpose and
need of additional wastewater capacity for future growth, nor NCDWQ's desire to
remove the discharge from the headwaters of Utley Creek.
Town of Holly Springs Page 5
Environmental Assessment August 2011

toff
C.2 Management Option B: Optimum Operation of Existing Facilities
The existing UCWRF is currently permitted to discharge 2.4 mgd at the current location.
This facility is being operated to meet the current 2.4 mgd NPDES limits. The review of
recent plant records indicates that the UCWRF is currently operating efficiently.
NCDWQ has indicated it would not allow an expansion in the permitted capacity above
2.4 mgd at the current discharge location. While the existing facility could treat more
wastewater, improvements are needed onsite to meet the speculative limits for nutrients
provided by NCDWQ 8 mgd. Optimal operation would not meet the growth needs of the
town at the current discharge location since higher flow cannot be permitted there.
Optimal operation would not meet the NPDES permit limits at an alternative discharge
location. Thus, optimal operation does not meet the project purpose and need and is not
considered further in this document.
C.3 Management Option C. Harnett County Regional Interconnection
Under this Option, the Holly Springs would convey up to 8 mgd of wastewater to the
North Harnett Regional WWTP at Lillington. Continuing to treat and discharge 2.4 mgd
at the UCWRF and transferring 5.6 mgd to Harnett County was considered, however, this
does not meet NCDWQ's desire to remove the discharge from the headwaters of Utley
Creek.
r"1
The WWRWRF FEIS and ROD evaluated this alternative for Holly Springs. The
analysis completed for that document indicated that Harnett County would need to
expand one of its treatment facilities to accommodate the flow from Holly Springs. In
addition, this alternative would result in extensive impacts from a raw wastewater
conveyance facility including multiple stream crossings, wetland impacts, and other risks
from increased conveyance of raw wastewater. Based on the lack of capacity at the
North Harnett County WWTP, which does not meet the project purpose and need, and the
higher environmental impacts associated with this alternative, it has been eliminated from
further consideration.
C.4 Management Option D: Treatment at the Western Wake Regional WRF
Under this Alternative, Holly Springs would construct a raw wastewater transmission
system to convey 8 mgd to the WWRWRF site. The first phase of the WWRWRF has
been designed and will begin construction in the Fall of 2011.
This alternative was reviewed in the Western Wake FEIS as part of the various regional
systems evaluated and was eliminated based on cost. To achieve the capacity needed,
Holly Springs would have to purchase 8 MGD of capacity in the WWRWRF and a
corresponding share in the WWRWRF effluent conveyance to the Cape Fear River. In
2006 the estimated capital cost of raw wastewater conveyance and treatment facilities for
3.6 mgd capacity exceeded $63m and the present worth exceeded $72m (all in 2006
dollars). The WWRWRF, which is about to go to construction, would likely need to be f,,*�
Town of Holly Springs Page 6
Environmental Assessment August 2011

expanded or components redesigned to accommodate the additional flow from Holly
Springs, resulting in additional expenses. The Western Wake Partners cannot delay their
schedule due to interbasin transfer certificate requirements to return wastewater to the
Cape Fear River and conveying raw wastewater to the proposed WWRWRF would not
meet the purpose and need of that facility. The FEIS and ROD determined Holly Springs
should continue to operate its own treatment facilities for flows of 6 and 8 mgd.
Transferring raw wastewater would require the installation of a major wastewater
pumping station at Utley Creek, and a flow diversion system. The wastewater pump
station and forcemain length and routing would be similar in scope to the Cape Fear
River effluent conveyance alternatives (Alternative E-1), but would have the additional
potential impacts of conveying raw wastewater rather than treated effluent. Continuing
to treat and discharge 2.4 mgd at the UCWRF and transferring 5.6 mgd to the WWRWRF
was considered, however, this does not meet NCDWQ's desire to remove the discharge
from the headwaters of Utley Creek.
This option has higher impacts from conveying raw wastewater than treating at the
current plant site, does not meet the WWRWFR purpose and need, and has a higher cost.
Thus, it is eliminated from further detailed study.
C.5 Management Option E. Wastewater Treatment Facilities Expansion and
Discharge Relocation
The UCWRF is currently permitted to discharge up to 2.4 mgd of wastewater into Utley
Creek. In order to meet the projected wastewater flows of 8.0 mgd for the 2030 planning
period, the Town would upgrade and expand the existing facility as needed to meet more
stringent nutrient limits and relocate the discharge from the current location in the
headwaters of Utley Creek.
Potential alternatives for the discharge of the effluent from the UCWRF evaluated herein
include:
➢ Alternative 1 (Section 1.5.1): Cape Fear River Discharge: This alternative
assumes the effluent is conveyed to the WWRWRF and ultimately discharged
into the Cape Fear River. This alternative was preferred in the 2007 EA and FNSI
to comply with the NCDWQ desire to remove the discharge from Utley Creek.
➢ Alternative 2 (Section 1.5.2): Lower Utley Creek Discharge: This alternative
assumes the effluent is conveyed downstream below Greentree Reservoir and is
discharged into Utley Creek upstream of Harris Lake.
➢ Alternative 3 (Section 1.5.3): Land Application - This alternative assumes the
effluent is land applied.
➢ Alternative 4 (Section 1.5.4): Wastewater Reuse - This alternative assumes the
effluent is disposed of via combinations of landscape irrigation, industrial usage,
and bulk reclaimed water.
Town of Holly Springs Page 7
Environmental Assessment August 2011

I�1
Details of each of the alternatives are discussed in the following sections, including a
discussion of the UCWRF process improvements required to upgrade the facility to meet
more stringent nutrient limit requirements now proposed for the Cape Fear River and the
Lower Utley Creek alternatives. All plant treatment process improvements would be
made on previously disturbed land on the existing plant site and there would be minimal
impacts to environmental resources from the proposed plant upgrades under any of the
discharge location alternatives. Thus, the environmental impacts on the plant site would
be the same under each action alternative. Each individual discharge alternative is
described in detail below.
C.5.1 Cape Fear River Discharge
This alternative involves pumping treated effluent from the UCWRF to the WWRWRF
effluent pump station and force main (Figure 1) which will then convey the treated
effluent jointly to a discharge location in the Cape Fear River downstream of Buckhorn
Dam. This alternative has been fully documented in the WWRWRF FEIS and ROD
(Appendix C) and the route was selected to minimize environmental impacts. A
summary is provided here for reference.
For Holly Springs, this discharge scenario would involve construction of a new treated
effluent pumping system on the UCWRF site, along with approximately 33,700 linear
feet of new 36-inch force main, to transport the treated effluent to the WWRWRF
regional pump station and force main, for joint conveyance to the Cape Fear River. /,a..t
Revised 2010 Speculative Limits for the Cape Fear River discharge (Table 2) are more
stringent than the initial 2004 speculative limits and those issued for Harris Lake/Lower
Utley Creek. Compliance with these lower limits would involve additional costs
including denitrification filters. UCWRF treatment process improvements proposed as
part of this alternative include:
• Supplemental carbon feed system
• Denitrification Filters
• Upgraded coagulant feed system
• Effluent and Reclaimed Water pumping facilities
• Biosolids handling upgrades including:
o Decant clarifier
o Additional interchange tanks
o Sludge dewatering facilities
This alternative would cost the Town approximately $47 million to construct and operate
(Appendix D). In addition, impacts from construction of the pipeline would include
approximately 0.13 acres of wetlands and 6 temporary stream crossings.
Several factors led to this alternative being less practical than the preferred alternative.
The potential expansion of the Shearon Harris Nuclear Plant would require an additional
withdrawal from Harris Lake for cooling purposes. The removal of the effluent discharge
from Utley Creek would reduce available water supply in the lake, thereby increasing the
Town of Holly Springs Page 8
Environmental Assessment August 2011

amount of water that the nuclear plant would have to transmit into the lake for cooling
1
from the Cape Fear River. This could have an adverse effect on aquatic habitat and
downstream flow of that (Cape Fear River) system. The environmental impacts are
presented in Table 4. Also, the present worth cost of this option is more than twice that
of the preferred alternative, which in the current economic climate is a major
consideration for the Town.
The overall environmental impact of this alternative is similar to a Harris Lake drainage
basin discharge (Table 4). However, due to the detrimental hydrologic effect of
removing flow from Harris Lake and the high cost of construction of this option a Lower
Utley Creek discharge was considered more practical for the Town.
Table 2: Cape Fear River Discharge Limits
Parameter
2004 Speculative
Limits
2011 WWR
Final Limits
Flow, mgd
Up to 8.0
Up to 8.0
BOD5, mg/L
5.0 (10.0)
5.0 (10.0)
Total Suspended Solids, mg/L
30.0
30.0
Ammonia Nitrogen, mg/L
1.0 (2.0)
1.0 (2.0)
Total Nitrogen, lbs/day
4002
Mass based on
3.5 mg/L 5
Total Nitrogen, mg/L
----
5.0
Total Phosphorus, lb/day
1333
Mass based on
0.5 mg/L 5
Total Phosphorus, mg/L
----
0.75
Fecal Coliform, #/100 mL
200
200
Dissolved Oxygen, mg/L
6.0
6.0
pH, units
6-9
6-9
' Season limits, summer April -October (winter November -March)
Z Mass limits based on 6 mg/L TN and the permitted flow
3 Mass limits based on 2 mg/L TP and the permitted flow
4 Monthly maximum concentrations (April to October)
S Mass based TN and TP limits (April to October)
C.5.2 Lower Utley Creek Discharge (Preferred Alternative)
This alternative, which is the preferred alternative, involves discharging treated effluent
from the UCWRF downstream into Lower Utley Creek below Greentree Reservoir within
the future proposed Harris Lake normal pool elevation of 240 feet MSL. This projected
normal pool elevation is based on a proposed expansion of the Shearon Harris Plant and
140111� associated expansion of Harris Lake for additional cooling water. The effluent pipeline
would consist of approximately 11,700 linear feet of 48-inch diameter gravity line.
Town of Holly Springs Page 9
Environmental Assessment August 2011

/0010�
Design of the effluent pipeline will include a cascade aeration structure near the
discharge point which remain in place at the future 240 lake level.
As noted above, the Lower Utley Creek speculative limits are more stringent than the
existing UCWRF was designed to meet. The following treatment process upgrades
provide 8 mgd of capacity and an additional margin of safety to comply with the more
stringent nitrogen and phosphorus limits.
• Supplemental carbon feed system
• Coagulation basin and additional disc filter
• Upgraded coagulant feed system
• Reclaimed water pumping and effluent flow measurement
• Biosolids handling upgrades including:
o Decant clarifier
o Additional interchange tank
o Sludge dewatering facilities
This alternative would cost approximately $20 million to construct and operate
(Appendix D). The movement of the effluent discharge downstream would reduce
nutrient loading on the upper portion of Utley Creek including Thomas Mill Pond and
Greentree Reservoir. It would also reduce base stream flows and aquatic habitat to levels
similar to the section of Utley upstream of the UCWRF. In addition, impacts from
construction of the pipeline would include approximately 0.10 acres of wetlands and 7 elol t'
temporary stream crossings. The discharge would be assimilated in Utley Creek and
Harris Lake, based on the issuance of speculative limits for this location (Appendix D).
The speculative limits are summarized in Table 3.
Table 3: Lower Utley Creek Discharge Limits
Parameter
Harris' Lake &
Lower Utley Creek
Flow, mgd
6.0 & 8.0
BOD5, mg/L
5.0
Total Suspended Solids, mg/L
30.0
Ammonia Nitrogen, mg/L
1.0
Total Nitrogen, mg/L
5.0
Total Phosphorus, mg/L
0.50
Orthophosphate, mg/L
0.27
Fecal Coliform, #/100 mL
200
Dissolved Oxygen, mg/L
7.0
pH, units
6-9
Town of Holly Springs Page 10
Environmental Assessment August 2011

The proposed effluent line alignment was determined via a step-down analysis beginning
with Geographical Information System analysis of existing environmental data and
followed by field verification of major environmental constraints such as steep
topography, major wetland areas, and tributaries. Following this analysis and
determination of an initial alignment, detailed wetland and stream delineation and natural
resource assessments were performed and the line further adjusted to minimize impacts.
Several other locations for discharge along Utley Creek and Harris Lake were considered
but deemed not practical. Discharges above Greentree Reservoir were discouraged by
NCDWQ due to uncertainty about Progress Energy's operation of the impoundment,
while a discharge directly into Harris Lake would increase costs of construction and
stream and wetland impacts.
A discharge into the Harris Lake watershed is preferred over a Cape Fear discharge for
several key reasons. First, the overall environmental impact of a Harris Lake watershed
discharge is similar to or less than the environmental impact of a Cape Fear River
discharge (Table 4). Speculative limits have been issued by NCDWQ for a Harris Lake
and an Utley Creek discharge, suggesting that either is an acceptable alternative when
considering water quality. The much higher cost of construction of the Cape Fear
alternative, combined with the reduction in need for pumping cooling water from the
Cape Fear River to Harris Lake to support the proposed Shearon Harris nuclear plant, led
lomo\ to the selection of the Lower Utley Creek discharge as the preferred alternative.
C.5.3 Land Application
This alternative would involve the application of treated wastewater effluent to areas with
suitable soils to allow infiltration and attenuation of effluent pollutants. While some soils
suitable for land application are present in the vicinity of the UCWRF, the amount of land
available for this activity is extremely limited. Approximately 3,600 acres would be
necessary to process an average of 8.0 mgd of effluent. This option is estimated to cost
in excess of $93 million to construct and operate. More details are provided in the EAA
in Appendix D. This alternative was deemed impractical due to the cost and lack of
available acreage, the potential effects of clearing the land, and the long term effects of
land application on future water quality.
C.5.4 Wastewater Reuse
This alternative would involve the use of reclaimed wastewater as a supply for certain
uses such as industrial cooling and irrigation. The Town has been planning conjunctive
wastewater reuse since 2000, began implementation in 2006, and recently initiated its
first reclaimed distribution system in 2010. However, due to the limited uses allowed for
this resource, the amount of effluent used in this capacity cannot meet the full purpose
and need of this project. Therefore, reuse was not chosen as the preferred alternative, but
the Town will continue to aggressively implement it as a part of a larger program to
complement its primary discharge alternative.
Town of Holly Springs Page 11
Environmental Assessment August 2011

Reclaimed water usage in this area of North Carolina is predominately seasonal
landscape irrigation, with peaks in June to September. It is likely that during winter
months no reclaimed water irrigation would occur and the full effluent volume would be
discharged to the receiving waters. While this option does not offer a year round
alternative to a discharge system, it does result in a reduction of nutrient loading in the
summer months, which is most critical to the receiving waters. Thus the Town will
continue to pursue wastewater reuse opportunities, but this alternative does not meet the
project purpose and need.
Table 4: Alternative Discharge Location Summary
Cape Fear Discharge*
Lower Utley, Creek Discharge
Cost
$47 million
$20 million
-TopographyNo
permanent change
No permanent change
Soils
34 ac. disturbed (most roadside)
15.3 ac. disturbed
Land Use
30.9 ac. Easement
10.3 ac. Easement
Wetlands
0.13 (0.03permanent) ac.
0.10 (0.06permanent) ac.
Streams
6 crossings:
- 3 intermittent
- 3 perennial
7 crossings:
- 3 intermittent
- 4 perennial
Prime/Unique
Farmland
15.7 ac.
3.7 ac.
Public Areas
Gamelands — minor impact
Gamelands — minor impact
Archaeological/
Historical
None
None
Air Quality
Pump station & generator
Temporary (construction)
Noise Levels
Temporary (construction)
Temporary (construction)
Water Resources
Eliminates loading and reduces
flow in Utley Creek; minor transfer
of water out of Harris Lake
watershed
Eliminates loading and reduces
flow in upper Utley Creek;
continued supply to Harris Lake
watershed
Forests
2.4 ac.
13.7 ac.
Shellfish/fish
Reduction of habitat in all of Utley
Creek; improved water quality in
impounded stream areas
Reduction of habitat in upper
Utley Creek; improved water
quality in impounded stream
areas
Wildlife/
Vegetation
2.4 ac. habitat
13.7 ac. Habitat
Toxic Substances
I None anticipated
None anticipated
*Numerical data from WWRWRF FEIS.
Town of Holly Springs Page 12
Environmental Assessment August 2011
ka

l; t �pring
Cape Fear Discharge
W d• c�
1 Proposed 33,700 linear 11 fall 5�e
36" effluent force main •'• Prin Z
. Proposed 1,700 ft sA� in
r 48 it eM ent line
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LEGEND
':? 1 Municipalities - Powell Bill 2009 USGS Surface Waters
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Proposed Project
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„••'• ........ 240' MSL
}r. • - — Streets - Wake County -------- Harris Lake Gameland Boundary
CAROLINA Data Sources: USGS- Streams andSurFace Waters • N Figure 1: Vicinity Map
ECOSYSTEMS, INC. NCOneMap-River Basins 1000 0 1000 2000 3000 4000 Feet
: (91 NC 42 W, 5 F: (91 NC 5- 520 NCDOT l Primary Roads Po arcs),+ m6m� Utley Creek W WTP DischargeJEA
P: 919 1 145 F: 919)sion: 4 Municipalities from 2009 Powell Bill Town of Holly Springs
ate: July 2011 Version: V4 Wake County -Streets Y

}
S
� �
Pi11,700 linear ft
heffluent line H0 y Springs
Thomas Milt
entree Pond —� �JiZLT T?�
LEGEND
Municipalities - Powell Bill 2009
Parcels - Wake County May 2010
US Highways - NCDOT 2010
NC Highways - NCDOT 2010
— Streets - Wake County
--•••--• Harris Lake Gameland Boundary
........ Future Hams Lake Boundary
240' MSL
— USGS Surface Waters
�i USGS Streams
�i 100 yr Floodplain - NC Floodmap
— Delineated Wetlands - CEI 2010
CAROLINA
ECOSYSTEMS, INC.
3040 NC 42 W, Clayton, NC 27520
P: 919 fi069145 F: 919-585-5570
Date: July 2011 1 Version: V4
Discharge
I -
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Figure 2: Site Plan
Utley Creek W WTP Discharge EA
Town of Holly Springs

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CAROLINA Data Sources: Wake County Soil Survey N Figure 3: soil Survey
ECOSYSTEMS, IhI<':. Map Sheets: 82,83,89,8c90 1000 0 1000 2000 Feet
3049 42 w, Clayton, NC 27520 Utley919)-585-5570 Creek W WTP Discharge EA
Date: LZI 2011145 F. Version: V4 Town of Holly Springs

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Figure 4: USGS Map
COSYSTEMS, INC.
Sources: NCNI-IP- Significant Natural Heritage Areas 2010
Utley Creek W W'f P Discharge EA
y
Town of Holly Springs
3040 NC 42 W, Clayton, NC 27520
P: 919 fi06-9145 F: 919 585-5570
CEI - Field Assessed Streams
CEI - Field Assessed Wetlands
(all data collected with sub -meter GPS)
See Figure 5 for impacts at each crossing
Date: Jul eon Version: V4

Lower Utley
Creek Discharge
X-03 -
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X-06
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within Corridor
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Lower UUep Creek Discharg
CAROLINA Data Sources: NCDOT- 2007 LIDAR based 4'Conmurs
ECOSYSTEMS, INC. CEI - Field Assessed Streams
3040 NC 42 W, Clayton, NC 27520 CET - Field Assessed Wetlands
P: L912145 R 919 585-5570 (all data collected with sub -meter GPS)
Datelul 2011 Version: V4 _ _
anent
1 77 1 307 1 0.06 1 0.10
N Figure 5: Wetland Map
500 0 500 IOOD 1500 Feet
Utley Creek W WTP Discharge EA
Town of Holly Springs

Town of Holly Springs
Wastewater Discharge Alternatives
Evaluation & Expansion
Engineering Alternatives Analysis
Responsible Agency: Department of Environment & Natural Resources
Division of Water Quality — Planning Section
1617 Mail Service Center
Raleigh, NC 27699
Consultants
Hannah Stallings, SEPA Coordinator
[phone]
hannah.stallinas[7a cdenr.aov
Davis -Martin -Powell & Associates, Inc.
6415 Old Plank Road
High Point, NC 27265
NC Firm F-0245
Michael L. Slusher, PE
[phone]
MS lu sher(a)d m p-in c. com
Carolina Ecosystems, Inc.
3040 NC 42 West
Clayton, NC 27520
Phil May
[phone]
Phil. Mav aacarolinaeco.com
Owner: Town of Holly Springs
128 South Main Street
PO Box 8
Holly Springs, NC 27540
Stephanie L. Sudano, PE
[phone]
stephanie.sudano a( )hollvsprinasnc.us

/'1
i. PROJECT SUMMARY
0 Introduction
Davis -Martin -Powell and Associates was retained by the Town of Holly Springs, NC to prepare an
Engineering Alternatives Analysis (EAA) addressing wastewater treatment system improvements
at the Utley Creek Water Reclamation Facility (UCWRF) to determine the most practicable
discharge system. Preparation of this document was recommended in a February 2010
Speculative Limits letter from the Division of Water Quality in response to the Town's request for
speculative limits for discharge into Harris Lake.
The Town of Holly Springs is a growing community located just south of the Research Triangle
Park (18 miles) and Raleigh -Durham International Airport (23 miles) in western Wake County
(Figure i-1). Holly Springs is bordered on the north by the Extra Territorial Jurisdiction (ETJ) area
of Apex; on the east by the Cary ETJ; on the south by the Fuquay-Varina ETJ; and on the west
by property owned by Progress Energy. There is a large amount of land both southwest and
northwest of Holly Springs' town limits that does not currently lie within any corporate limits.
Figure i-1
RWI �®
Molly Sprang, /,
Town of Holly Springs
Wastewater Discharge Alternatives Evaluation & Expansion
811WO118:12:00AM Hdly Spdngs FAA F1m108 10_2011.dou

1.2 Background
The UCWRF serves the Town of Holly Springs and surrounding areas, and is located in Wake
County, North Carolina. The UCWRF is currently permitted to discharge a monthly average
wastewater flow rate of up to 2.4 million gallons per day (mgd) into Utley Creek, a tributary to
Harris Lake, in the Cape Fear River Basin.
The UCWRF was first constructed in the late 1980's with a capacity of 0.25 mgd, and quickly
expanded to 0.5 mgd in 1994. With rapid growth occurring, the Town initiated a 201 Amendment
in 1997 which led to the UCWRF expansion to 1.5 mgd in 1999. During this process DWQ
expressed concerns about impacts on Utley Creek especially Thomas Mill Pond and Harris Lake.
In March 2003 Holly Springs was issued an Utley Creek NPDES permit for 2.4 mgd, with the
condition that the Town would investigate a regional solution for increased flows.
The Town of Holly Springs then contracted with Davis -Martin -Powell and Green Engineering in
2004 to prepare another 201 Facilities Plan Amendment (hereafter referred to as "201 Plan") to
evaluate wastewater treatment options to meet the Town's growing needs. Based on the flow
projections, the Town would need 6.0 mgd (monthly average) treatment capacity for the 2030
planning period. The 201 Plan analyzed the following alternatives to provide wastewater
treatment capacity:
• Land Application
• Expansion of the UCWRF to 2.4 mgd and transfer of 3.6 mgd to Harnett County North
Regional VW11TP at Lillington
• Expansion of the UCWRF to 2.4 mgd and transfer of 3.6 mgd to the Western Wake Regional
WRF for treatment
• Wastewater Reuse System
• Expansion of the UCWRF to 6.0 mgd & convey treated effluent to Cape Fear River with
Western Wake Partners
The 201 Plan was approved in fall 2006 and recommended the expansion of the UCWRF to meet
the Town's wastewater needs through 2025. NCDWQ issued a FONSI for this treatment facility
expansion in February 2007 with language stating that future permits for, or authorizations to
construct, the UCWRF would contain a condition that the Town would convey treated effluent to
Town of Holly Springs 2
Wastewater Discharge Alternatives Evaluation & Expansion
8115r2011 8:12:00 AM Holly Springs EAA Final 08_10 2011.docx

the Cape Fear River with the Western Wake Partners, when that system was available. A copy
of this FONSI is included in Appendix B.
The Town's UCWRF Upgrade and Expansion project proceeded into final design, which was
approved and construction contracts awarded in fall 2007. Construction started in January 2008
and much of the new biological treatment process was placed into service in August 2009. The
overall project was substantially completed in summer 2010.
i.3 Western Wake Regional Wastewater Management Facilities
As early as 2002, six Wake County local governments (including Holly Springs) began working
together to evaluate options for providing long-term wastewater management services for
western Wake County. The Western Wake Partners, comprised of four local governments
(including Apex, Cary, Morrisville and Holly Springs) proceeded with planning for regional
wastewater treatment facilities to serve wastewater needs of western Wake County through the
year 2030. The Western Wake Partners and US Army Corps of Engineers (USACE) developed
an Environmental Impact Statement, which was finalized in 2009, with a Record of Decision
(ROD) issued in July 2010 supporting the implementation of the project.
The Town of Holly Springs has participated in the Western Wake Project as a result of DWQ's
preference for regional cooperation, as stated in the 2007 FONSI for the UCWRF expansion that
"any Authorization to Construct or other necessary permits (orders, etc.) for expansion of the
Utley Creek WWTP will include a condition stating that the treated effluent must be removed from
Utley Creek by the date established in the Certificate authorizing the Towns of Cary, Apex, and
Morrisville and Wake County to Increase Their Transfer of Water from the Haw River basin to the
Neuse River basin under the Provisions of G.S. 143-215.221." As stated in the USACE ROD,
NCDWQ has indicated that as long as the Western Wake Partners are complying with the
requirements of the IBT certificate, the Town of Holly Springs will be deemed to be meeting the
requirements in the FONSI and that no modification is required. (USACE ROD, 2010).
Jointly, the Partners plan to build interceptors, force mains, and pump stations to convey raw
wastewater to a new water reclamation facility, along with discharge facilities to convey the
treated effluent to the Cape Fear River below Buckhorn Dam. Various alternatives and sites were
considered which have included Holly Springs as a participant in only effluent discharge facilities.
Town of Holly Springs 3
Wastewater Discharge Alternatives Evaluation & Expansion
8/152011 8:12:00 AM Holly Springs EAA Final 08 10 2011.docx

The Holly Springs 201 Plan (2006) recommendations included subsequent construction of an
effluent conveyance system to the Western Wake Regional WRF (WWRWRF). Effluents from
the WWWRF and UCWRF would be combined and then conveyed and discharged into the Cape
Fear River. Speculative limits for this discharge point were issued for both facilities in December
2004, up to 30 mgd from WWRWRF and up to 8 mgd from Holly Springs (maximum month flows).
The WWRWRF project experienced several delays, including the required preparation of an EIS
which began in 2007 and culminated with the USACE ROD. As a result, the original 2011
completion date has been pushed back until at least December 2013. The estimated cost to
Holly Springs increased significantly due to additional work, inflation, and other delays, with the
next phase of construction (effluent pumping, forcemain, and the Partner's effluent conveyance)
now estimated at $39 million. This option would bring the Town's total wastewater infrastructure
improvement costs to $67 million. The overall economic turndown that began in 2008 and is
continuing at this time has forced the Town to further evaluate expenditures on all capital and
infrastructure projects.
Holly Springs was a participant in only the effluent conveyance components of the Western Wake (4"I ,
Partners project, and the design and capacity of the WWRWRF treatment facilities are
independent of Holly Springs' effluent. When Holly Springs withdrew from the partnership, there
was minimal impact to the overall schedule for the remaining partners, as the wastewater
treatment plant site is the first contract to be let and the effluent conveyance construction
beginning approximately 6 months later. Based on preliminary evaluations the effluent pumping
station capacity would be reduced, and the effluent forcemain diameter might be reduced from
60" to 54" which would reduce the construction cost.
There have also been several developments in the planning area and during the planning
process which have opened new potential discharge alternatives for Holly Springs such as:
• Progress Energy Carolinas announced plans to construct additional nuclear power reactors at its
Shearon Harris Facility. To supply adequate cooling water for the new reactors, Harris Lake level
will be expanded, and water must be pumped from the Cape Fear River to supplement the natural
drainage areas. Holly Springs and/or Western Wake Partners effluent discharge into Harris Lake
could in part replace water needed from the Cape Fear River.
• The Western Wake Partners began an evaluation of a discharge into Harris Lake as an alternative
to the costly Cape Fear effluent conveyance system. The Western Wake Partners commissioned eoll')
Town of Holly Springs 4
Wastewater Discharge Alternatives Evaluation & Expansion
8/15/2011 8:12:00 AM Holly Springs EAA _Final 08 10 2011.docx

?"01�
water quality monitoring and water quality modeling to determine if both the WWRWRF and
UCWRF effluents could be discharged into Harris Lake without impairing water quality. While this
investigation may have shown Harris Lake was a practicable alternative discharge location; the
additional regulatory approvals required for Cary and Apex IBT certificate could further delay the
project by at least three years and more likely 5 years. The Partners, faced with a June 2014
deadline, determined they could not continue to delay the project, and Harris Lake was determined
to not meet the purpose and need for the Western Wake WRF discharge.
• Since Western Wake Partners evaluation demonstrated that Harris Lake could support the
wastewater discharges, the Town of Holly Springs continued to pursue this option independently.
Additional modeling was conducted to analyze a Holly Springs discharge into the White Oak Arm of
Harris Lake, and presented to NCDENR-DWQ in December 2009 for review. In February2010,
the Town of Holly Springs received speculative limits for a Harris Lake discharge of 6 and 8 mgd.
• The Western Wake Partners' final Cape Fear River NPDES limits were more stringent than the
2005 speculative limits. These more restrictive limits include seasonal (April to October) mass
limits based on permitted flow and a value of 3.5 mg/L for TN and 0.5 mg/L for TP. In addition,
there is a monthly average concentration limit of 5.0 mg/L for TN and 0.75 mg/L for TP, also
applicable from April to October. These changes will significantly affect the level of treatment
required at the UCWRF.
11.4 Purpose and Need
The purpose of this Engineering Alternatives Analysis (EAA) is to evaluate the various discharge
alternatives available for the wastewater effluent generated from the Town's expanded treatment
facilities. This is required with any NPDES application in accordance with 15A NCAC
2H.0105(c)(2) as noted in the speculative limits letters. The 2007 FONSI has justified the project
growth and wastewater flows for Holly Springs and the Western Wake FEIS and ROD were
subsequently justified the 8 mgd.
This EAA is limited to review of viable alternatives to a Cape Fear River discharge, and including
management options of Optimum Operation, Land Application, and Wastewater Reuse.
Connections to other systems (Regional Solutions) were evaluated in the 201 Plan and FEIS and
since the UCWRF plant has been expanded, are revisited in this report. This report was
prepared using the guidelines established in the "Engineering Alternatives Analysis (EAA)
Guidance Document, North Carolina Division of Water Quality/ NPDES (June 23, 2005)" and the
Construction Grants & Loans Division's "Guidance for the Preparation of Engineering Reports"
(April 2005).
Town of Holly Springs
Wastewater Discharge Alternatives Evaluation & Expansion
8/1 SQ011 8:12:00 AM Holly Springs EAA _Final 08 10 2011.docx
5

This Page Intentionally Blank
id
Town of Holly Springs
Wastewater Discharge Alternatives Evaluation & Expansion
8/15120118:12:00 AM Holly Spdngs EAA Jinal 08 10 2011.docx

Figure 1-3
Population Projections
¢:cm
sc,om
zo.cm
:c.cm
30.0m
20,13m
20.0m
20m 2c5 _..� ...a
2=0 2u_a
Town of Holly Springs 13
Wastewater Discharge Alternatives Evaluation & Expansion
8/15W181200 AM Holly spnngs EAA Final08_10_2011.nocx

5W
1.3 Existing Land Uses
The Town currently has zoning ordinances in place which include the following main categories
and corresponding districts.
❑ Residential: Single Family; Multifamily; High -Density Multifamily
❑ Commercial/Mixed Use: Neighborhood Village; Local Business; Town Village; Office,
Research, and Development Park; Community Business; General Business
❑ Industrial: Warehouse/Distribution; Light Industrial; General Industrial
Areas south and west of Holly Springs are experiencing more rapid residential growth.
Commercial and industrial development is expected to dominate the north and west areas of
Town. The proposed Wake County Outer Loop will intersect with the Holly Springs Bypass
immediately north of Town and will likely support more commercial and industrial growth. The
potential growth area west of Town extends to the property owned by Progress Energy. This
area is logical for industrial development.
Figure 1-4 on the following page shows the current Land Use Plan for the Town of Holly Springs
and surrounding areas.
W
Town of Holly Springs 14
Wastewater Discharge Alternatives Evaluation & Expansion
8/15/2011 8:12:00 AM Holly Springs EAA _Final 08 10 2011.docx

SECTION 2.0--- EEVALUATION' OF ALTERNATIVES
2.1 General
Several Wastewater Management Options were evaluated in preparation of this EAA and the
accompanying EA. These include No Action, Optimum Operation, Regional Solutions, UCWRF
Discharge Relocation and Expansion. These alternatives were evaluated in the 2006 201/EA
and WWRWRF FEIS. Feasible alternatives will be evaluated in the following sections.
2.1.1 Management Option A: "No Action"
The "no action" alternative is not considered feasible because it would not meet immediate and
projected needs for wastewater treatment capacity. The Town has invested nearly $29 million in
the upgrade and expansion of its wastewater treatment facilities over the past 5 years to expand
the treatment capacity to 6 mgd. With no further improvements, the usable capacity would be
limited to the current NPDES discharge of 2.4 mgd, plus any reclaimed water usage.
"No Action" would require future development to be served by private wastewater treatment
facilities or septic tanks. Use of private wastewater treatment facilities is not considered
acceptable because such facilities historically have resulted in poor quality effluent being
discharged to receiving streams. Streams with sufficient assimilative capacity for new wastewater
discharges are also unlikely to be available in the Town's service area. Septic tanks are also not
acceptable on an extensive scale because many of the soils in Wake County have moderate to
severe restrictions for septic tanks due to low soil permeability. In addition, projected
development is expected to be at or near urban densities throughout the portion of the service
area within the Town's growth areas and the adjoining county residential and commercial service
areas.
The lack of available wastewater capacity will also limit industrial development potential which in
turn could have a negative economic impact on the Town's growth and development. Economic
development has recently slowed, but is beginning to rebound. Competition for industry and the
jobs industries provide is likely to be high as municipalities and the State of North Carolina try to
recover from the current economic downturn. A lack of sufficient wastewater capacity could
certainly result in lost economic development opportunities.
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This alternative will not be considered any further, as it does not meet the purpose and need of
additional wastewater capacity for future growth, nor NCDWQ's desire to remove the discharge
from the headwaters of Utley Creek.
2.1.2 Management Option B: Optimum Operation of Existing Facilities
The existing UCWRF is currently permitted to discharge 2.4 mgd at the current location and was
issued an ATC for 6.0 mgd. This facility is being operated to meet the current 2.4 mgd NPDES
limits. The review of recent plant records (Section 1.7.4) indicates that the UCWRF is currently
operating quite efficiently.
DWQ has indicated it would not allow an expansion in the permitted capacity above 2.4 mgd at
the current discharge location. While the existing facility could treat more wastewater and has
received an ATC for 6 mgd, improvements are needed onsite to meet the speculative limits for
nutrients provided by DWQ for 6 and 8 mgd. Optimal operation would not meet the growth needs
of the town at the current discharge location since higher flow cannot be permitted there. Optimal
operation would not meet the NPDES permit limits at an alternative discharge location. Thus, r
optimal operation does not meet the project purpose and need and is not considered further in
this document.
2.1.3 Management Option C: Harnett County Regional Interconnection
Under this Option, the Holly Springs would convey up to 8 mgd of wastewater to the North
Harnett Regional WWTP at Lillington. Continuing to treat and discharge 2.4 mgd at the UCWRF
and transferring 5.6 mgd to Harnett County was considered, however, this does not meet
NCDWQ's desire to remove the discharge from the headwaters of Utley Creek.
The WWRWRF FEIS and ROD evaluated this alternative for Holly Springs. The analysis
completed for that document indicated that Harnett County would need to expand one of its
treatment facilities to accommodate the flow from Holly Springs. In addition, this alternative
would result in extensive impacts from a raw wastewater conveyance facility including stream
crossing and wetland impacts and other risks from increased conveyance of raw wastewater.
Based on the lack of capacity which does not meet the project purpose and need and the higher
?ON
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environmental impacts associated with this alternative, it has been eliminated from further
consideration.
2.1.4 Management Option D: Treatment at the Western Wake Regional WRF
Under this Alternative, Holly Springs would construct a raw wastewater transmission system to
convey 8 mgd to the WWRWRF site. The first phase of the WWRWRF has been designed and
will begin construction in the Fall of 2011.
This alternative was reviewed in the Western Wake FEIS as part of the various regional systems
evaluated and was eliminated based on cost. To achieve the capacity needed, Holly Springs
would have to purchase 8 MGD of capacity in the WWRWRF and a corresponding share in the
WWRWRF effluent conveyance to the Cape Fear River. In 2006 the estimated capital cost of
raw wastewater conveyance and treatment facilities for 3.6 mgd capacity exceeded $63m and the
present worth exceeded $72m (all in 2006 dollars). The WWRWRF, which is about to go to
construction, would likely need to be expanded or components redesigned to accommodate the
additional flow from Holly Springs, resulting in additional expenses. The Western Wake Partners
cannot delay their schedule due to interbasin transfer certificate requirements to return
wastewater to the Cape Fear River and conveying raw wastewater to the proposed WWRWRF
would not meet the purpose and need of that facility. The FEIS and ROD resulted in Holly Springs
continuing to operate its own treatment facilities for flows of 6 and 8 mgd.
Transferring raw wastewater would require the installation of major wastewater pumping station
at Utley Creek, and a flow diversion system. The wastewater pump station and forcemain length
and routing would be similar in scope to the Cape Fear River effluent conveyance alternatives
(Alternative E-1), but would have the additional potential impacts of conveying raw wastewater
rather than treated effluent. Continuing to treat and discharge 2.4 mgd at the UCWRF and
transferring 5.6 mgd to the WWRWRF was considered, however, does not meet NCDWQ's
desire to remove the discharge from the headwaters of Utley Creek.
This option has higher impacts from conveying raw wastewater than treating at the current plant
site, does not meet the WWRWRF purpose and need, and has a higher cost. Thus, it is
eliminated from further detailed study.
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33

2.1.5 Management Option E: UCWRF Expansion and Discharge Relocation
The UCWRF has a current treatment capacity of 6.0 mgd and is permitted to discharge up to 2.4
mgd of wastewater into Utley Creek. In order to meet the projected wastewater flows of 8.0 mgd
for the 2030 planning period, the Town would upgrade and expand the existing facility as needed
to meet more stringent nutrient limits and relocate the discharge from the current location in the
headwaters of Utley Creek.
Potential alternatives for the discharge of the effluent from the UCWRF evaluated herein include:
• Alternative E-1: Cape Fear River Discharge: This alternative assumes the effluent is
conveyed to the WWRWRF and ultimately discharged into the Cape Fear River. This
alternative was preferred in the 2006 201 Plan to comply with the NCDWQ desire to
remove the discharge from Utley Creek.
• Alternative E-2: Lower Utley Creek Discharge: This alternative assumes the effluent is
conveyed downstream below Greentree Reservoir and is discharged into Utley Creek
upstream of Harris Lake.
Ao1
• Alternative E-3: Land Application - This alternative assumes the effluent is land applied.
• Alternative E-4: Wastewater Reuse - This alternative assumes the effluent is disposed
of via combinations of landscape irrigation, industrial usage, and bulk reclaimed water.
Details of each of the alternatives are discussed in more detail in the following sections, including
a discussion of the UCWRF process improvements required to upgrade the facility to meet more
stringent nutrient limit requirements now proposed for the Cape Fear River and the Lower Utley
Creek alternatives.
2.2 Treatment Process Upgrades
As previously noted, the UCWRF expansion was designed to meet NPDES effluent limits based
on the Cape Fear River speculative limits, which were proposed at 2 mg/L TP and 6 mg/L TN. To
achieve these goals the facility design included the following process components as described
previously in Section 1.7:
• A 5-stage biological nutrient removal (BNR) process
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e Secondary clarifiers with low surface loading rates
e Cloth media tertiary filters (Kruger DiscFilters)
e Supplemental coagulant chemical feed equipment
The current 5-stage BNR process is capable of achieving effluent total nitrogen levels between
4.0 and 5.0 mg/L. The biological phosphorus uptake process is also generally able to achieve TP
of 1.0 to 2.0 mg/L without any chemical precipitation. Generally accepted practice is to provide
additional treatment processes when lower effluent levels are required by NPDES permit.
During startup the UCWRF has been able to exceed these goals, however current hydraulic
loading is only at 60% of the online units' rated capacity. This high level of performance is based
upon the following operating criteria:
e Suitable ratios of influent BOD5, COD, to nitrogen and phosphorus
Maintenance of proper levels of activated sludge (MLVSS) in the aeration basins
14� e Proper management of biosolids wasting
To ensure compliance with the potential effluent limits less than 2 mg/L TP and/or 6 mg/L TN, a
variety of process upgrades could be incorporated into the existing wastewater treatment
process, as discussed in this section. Identification of the needed upgrades will be addressed in
the discussion of each individual discharge alternative (Sections 2.3 to 2.7)
2.2.1 Disc Filters Upgrade
The existing cloth media disc filters are excellent for normal solids reduction, because they are
relatively economical, have a compact foot print, and are easy to maintain. Disc filters also
require a very small volume of backwash water compared to deep bed filters.
Disadvantages with disc filters are the inability to operate in denitrification mode and a limited
ability to chemically remove phosphorus. Consultations with the filter manufacturers have shown
success in meeting a 0.5 mg/L TP limit with the current filter technology and the addition of a
coagulant mixing system immediately upstream of the filter units. This would improve the
efficiency of the chemical dosing system and the ability of the disc filters to remove effluent
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35

phosphorus. A fifth disc filter unit is also recommended to lower the solids loading rate and
provide capacity for the 8 mgd flow with one unit out of service.
2.2.2 Deep Bed Denitrification Filters
An alternative filter system utilizes deep bed filters for both normal solids reduction and
denitrification of nitrates (NO3-N) to nitrogen gas, which is released to atmosphere. Denitrifying
microorganisms attach to the filter media, which provides the support system for their growth. A
carbon source such as methanol, acetic acid, molasses, etc. is added upstream of the packed -
bed filter and a nitrified influent is filtered through the media. The deep bed filter system is well
suited for denitrification because it provides the necessary hydraulic detention time for the
biological reaction to take place. The filter media is composed of a coarse, hard, predominately
siliceous material (sand). Configuration and operation is very similar to a conventional water
plant filter system.
The additional detention time and media also enhance chemical phosphorus removal, as
compared to the existing disc filter, and some of the coagulant feed upgrades would not be r.y
necessary to meet the lower phosphorus limits.
Preliminary sizing criteria for denitrification filters are based on a loading rate of 2 gpm/SF of filter
area. A total filter area of approximately 2,780 square feet is needed to treat the 8 mgd design
flow. Four filter cells, are recommended so that one cell can be backwashed without excessive
loading on the remaining cells.
Disadvantages to deep bed filters are higher capital cost, larger footprint, relatively high
backwash rate of 6 gpm/SF, plus air scour, large capacity backwash pumps, backwash supply
and waste storage, and filter scour blowers. An upgrade to denitrification filters will require the
removal of the existing cloth media filters.
2.2.3 Supplemental Carbon Feed System
As noted above, a supplemental carbon source is required for the denitrification filters to remove
additional nitrogen. Supplemental carbon can also be feed into the second anoxic zone to
enhance biological denitrification. Methanol is the most common carbon source used at
`0'
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wastewater facilities; however cost and availability of alternate source chemicals would be
evaluated during design.
Depending on the biological nitrogen performance and seasonal effluent limits, the amount of
carbon added can be minimized to trim 1-2 mg/L of nitrates, or increased to remove up to 5 mg/L
nitrates. A typical methanol feed system would include an 8,000 gallon storage tank, metering
pumps, and ancillary equipment. An average feed rate would be a 100 gpd design capacity. The
alternative carbon sources have varying chemical and physical properties, so it may become
significantly more expensive to design storage and feed equipment to accommodate all possible
compounds.
2.2.4 Coagulant Feed System
UCWRF currently includes a coagulant feed system as a backup and enhancement for biological
phosphorus removal. The current chemical feed system was designed as polishing step to
remove about 1 mg1L TP to ensure compliance with the anticipated 2 mg/L effluent standard. It is
PAWN common practice to provide chemical backup to BNR processes to assist during process upsets,
seasonal changes, etc. Operating initially under the Town's current Utley Creek NPDES permit
PAWN
(2.4 mgd, equivalent 0.5 mg/L TP), the UCWRF has been able to successfully reduce TP to less
than 0.20 mg/L with aid of chemical precipitation, albeit at high dosages and high chemical cost.
The design was based on using ferric chloride as the coagulant because it is one of the more
aggressive metal salt compounds, however the feed equipment can also be used with several
aluminum compounds, and has initially been operated with sodium aluminate. As illustrated in
Table 2-1 chemical usage could increase 3 to 7 fold to meet lower effluent phosphorus standards.
As described in Disc Filter Upgrades, the filter supplier has recommended a new coagulant
system to enhance effectiveness of the coagulant, additional of a polymer to enhance
phosphorus removal. This would include a concrete mixing basin, vertical mixers; polymer feed
system, additional bulk storage, and a new building to house the chemical feed equipment.
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Table 2-1
Chemical Phosphorus Precipitation
TP reduction
2.5 to 1.5 mg/
2.0 33
6.0 98
8.0 130
TP reduction TP reduction
1.25 to 0.2 mg/L 2.5 to 0.2 mg/
104 226
310 680
413 905
If denitrification filters are determined to be necessary for compliance with lower nitrogen levels,
the disc filters would be removed. A separate coagulation mixing basin would not be needed but
would be incorporated in the deep bed filter inlet channel. Additional coagulant bulk storage and
a new building to house the chemical feed equipment would be needed.
Common to either type of filter technology, compliance with lower phosphorus limits would require
several associated improvements including additional chemical feed lines, an additional
coagulant bulk storage tank and secondary containment structure, and metering pumps .
2.2.5 Biosolids Handling Upgrades
The timely and efficient disposal of biosolids is critical to the overall operation of the treatment
process, and especially so when achieving low nutrient levels. While nitrogen is ultimately
converted to nitrogen gas, phosphorus is only removed from the waste treatment process via
effluent, sludge wasting, or sludge screening/grit.
The UCWRF Cannibal® Biosolids system includes a cyclone separator component to remove
grit from the RAS and research has shown is effective in ultimate phosphorus removal. This grit
stream can be disposed of in a municipal solid waste landfill.
A second 0.95 MG Cannibal® Interchange Tank will need to be constructed. This component
was not included in the initial construct because of conflicts with the current cascade aeration
structure. The Interchange will be needed before the UCWRF reaches 3 mgd of waste flow, and
lower nutrient limits justify its construction to provide operational flexibility.
IOMN
Town of Holly Springs 38
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r"o,51N
Research has also shown the Interchange Tank decant is high in phosphorus, and a Decant
Clarifier can be added to maximize phosphorus removal. The sludge collected will be wasted
directly to the aerobic digester. This component was initially included in the Upgrade and
Expansion design, but construction was delayed to coincide with the second Interchange Tank.
Finally, a Sludge Dewatering Facility is proposed to ensure biosolids can be wasted and disposed
of without the seasonal and wet weather impediments associated with liquid land application. The
Class B sludge cake can be stored onsite, then hauled away for agricultural land application, or
converted into a Class A product by composting or drying. The proposed dewatering facility
would likely include sludge pumps, polymer feed, a single belt filter press, and conveying system
for truck loading. The entire system will be enclosed in a building to minimize odors and protect
equipment.
2.2.6 Present Worth Cost Estimate
A preliminary engineering level cost estimate shows the construction costs and contingencies for
� the improvements required for each effluent discharge alternative. The compound amount (F) in
2010 dollars was unchanged from recent (2008) cost estimates. Recent year construction costs
are depressed, however, the conservative approach to account for variable construction market
conditions is to neither inflate nor discount the previous cost estimate methodology. This also
maintains consistency between the Town and Partners previous planning documents.
A construction contingency of 10% and a professional services allowance of 15% has been used
to calculate the total project costs. The Town's anticipated contribution to the Western Wake
Partners is included, and is based on the Western Wake Partners' Engineering Report (Brown &
Caldwell, June 2010) and subsequent data provided by the Town.
The net present value cost estimate was calculated over a 20-year period using a discount rate of
4.875%.
Town of Holly Springs 39
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2.3 Alternative 1: Cape Fear River Discharge
2.3.1 Background
As previously discussed, the Holly Springs 201 Plan (2006) recommended an effluent
conveyance system to the WWRWRF and a Cape Fear River discharge as the most viable
alternative evaluated. The 201 Plan presented the infrastructure upgrades necessary to meet
anticipated permit limits in the Cape Fear River at the current design capacity of 6.0 mgd and
maximum month of 8.0 mgd. This document was referenced in the preparation of the Western
Wake Partners' Environmental Impact Statement (FEIS) & Engineering Report (ER).
The 201 Plan developed a routing for the Utley Creek Effluent forcemain to the Western Wake
Partners proposed WWRWRF, located just north of Highway 1 and west of New Hill - Holleman
Road. This location has been commonly identified as "Site 14" in the Western Wake Partners
planning documents. During the Western Wake Partners EIS process, Site 14, along with
several other possible sites, were evaluated for location of the Partners wastewater treatment
/Mo� facilities. Issuance of the USCAE ROD has confirmed the selection of Site 14 as the WWRWRF
location. Figure 2-1 shows an overall layout of the proposed Holly Springs effluent conveyance
system from UCWRF to the WWRWRF site. Effluents from the two WRF's would be combined
and then conveyed and discharged into the Cape Fear River near Buckhorn Dam (Figure 2-2).
The current UCWRF treatment process design was based upon the speculative limits issued by
DWQ (December 2005). The final NPDES permit limits issued to the Western Wake Partners
were more stringent than the speculative limits to reduce nutrient loading in the Cape Fear River,
and this section's discussion is based on the final permit limits. Table 2-2 compares the 2004
Cape Fear speculative limits with the final Cape Fear River permit limits issued in January 2011.
This alternative was included in the planning and design documents of the Western Wake
Partners, including the FEIS and USACE ROD (July 2010). Holly Springs has completed
preliminary design of the pipeline and pump station. The issuance of the USACE ROD satisfies
the environmental review requirements for this alternative, and if implemented, USACE/DWQ
404/401 permit application can be submitted, along with an NPDES discharge permit application
for the Cape Fear River.
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n,
Table 2-2
Cape Fear River Discharge Limits
Parameter
Flow, mgd
.• Fear River
11.2011)
Up to 8.0
CapeFear River
Up to 8.0
BOD5, mg/L
5.0 (10.0)
5.0 (10.0)
Total Suspended Solids, mg/L
30.0
30.0
Ammonia Nitrogen, mg/L'
1.0 (2.0)
1.0 (2.0)
Total Nitrogen, Ibs/day
4002
Mass basedon
3.5 mg/L
Total Nitrogen, mg/L
----
5.0
Total Phosphorus, lb/day
133 3
Mass basedon
0.5 mg/L
Total Phosphorus, mg/L
----
0.75
Fecal Coliform, N100 mL
200
200
Dissolved Oxygen, mg/L
6.0
6.0
pH, units
6-9
6-9
' Season limits, summer April -October (winter November -March)
2 Mass limits based on 6 mg/L TN and the permitted flow
3 Mass limits based on 2 mg/L TP and the permitted flow
"Monthly maximum concentrations (April to October)
5 Mass based TN and TP limits (April to October)
2.3.2 New Infrastructure
Currently, the plant discharges treated effluent from the UV disinfection process through a gravity
outfall and cascade aerator into Utley Creek. To convey flow to the WWRWRF, an effluent pump
station and forcemain are required.
The new effluent pumping structure will be constructed west of the UV facilities. The effluent
structure will include four vertical turbine pumps for effluent transfer and three vertical turbine
reclaimed water supply pumps. The wetwell will be divided to allow the reclaimed water to be
shut down during periods of non-compliance with reclaimed standards. The reclaimed water
Town of Holly Springs 42
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chlorination facilities will also be relocated to the effluent pump station area, and chlorine contact
time will be provided to comply with reclaimed water standards.
All pumps will be provided with variable frequency drives to match flow rates and minimize
electrical operating costs. To meet reliability standards, a new standby diesel generator is
proposed for the effluent pumping system. A new building will be provided adjacent to the new
pump station to house chemical feed equipment, controls, and electrical switchgear.
The effluent forcemain will be a 36" diameter pipeline, with an overall length of 35,400 LF. As
shown in Figure 2-1, the majority of the forcemain route parallels existing public roads; however
temporary and permanent easements will be required in several locations due to stream
crossings, utility conflicts and topographic features.
Compliance with the more stringent phosphorus limits (0.5 to 0.75 mg/L TP) could be achieved by
chemical precipitation; however the lower summer nitrogen limits (less than 3.5 mg/L TN) will
require more extensive process modifications. To ensure compliance with the more restrictive
nutrient limits the following process modifications are recommended, as shown on Figure 2-3 and
described in more detail in Section 2.2:
• Replacement of existing Disc Filters with deep bed Denitrification Filters
• Supplemental Carbon Feed System
• Upgraded Coagulant Feed System
• Biosolids Handling Upgrades including the Decant Clarifier, additional Interchange Tank, and
Sludge Dewatering Facilities
The Western Wake Partners construction contracts would include the forcemain piping on Site 14
(north of Highway 1) and structures to receive the Holly Springs effluent. An effluent pump
station will be constructed by the Western Wake Partners to convey the combined effluents to the
Cape Fear River via about 11.75 miles of 60" diameter forcemain.
Town of Holly Springs 43
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Table 2-3
Alternative E-1: Cape Fear Discharge
Present Worth Cost Estimate
Estimated Costs
Pipe Material
$4,263,695
Valve Costs
$113,400
Air Release Valves
$72,000
Fitting Cost
$135,200
Equipment/Labor Cost
$1,188,000
Erosion Control
$177,000
Seed/Restoration
$122,0ff
Rock Excavation
$1,770,000;
Trenchless Cost
$625,000
Denitrification Filter Upgrades `.
$4,900,000
Supplemental Carbon & Coagulant Systems
$425,000
Biosolids Facility Upgrades
$2,339,000
Effluent Pump Station I
$2,250,0001
Subtotal
$18,380,300'
Contractor OH&P, Bonds, Insurance
$3,037,200 16.5%
Total Construction Estimate
$21,417,500
Professional Services
$3,212,600 15.0%
Contingencies
$2,141,800 10.0%
Western Wake Expenses
$12,967,400
Total Capital Cost
$39,739,300`
Present Worth Pipeline O&M
$675,600
Present Worth Effluent Pumping O&M
$2,069,300
Present Worth Advanced Treatment O&M
$4,602,700
Total Present Worth $47,086,900;
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WWREXWRF
M
AM
�HIQLY SPRINGS
w
�.
FORCIFPROPOSED 36"EFFLUENT
fORCF MAIN
1
\ IIMHIS -NII
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ih
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Engineering Alternatives Analysis Cape Fear Discharge Alternative E-1
dmp Discharge Alternatives Evaluation Proposed Forcemain Route

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Town of Holly Springs 48
Wastewater Discharge Alternatives Evaluation & Expansion
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Apex
l �
/ 9 _
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�J 1-15� yt sp �g
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,•�• dm Engineering Alternatives Analysis Alternative E-1. Cape Fear Discharge
P Discharge Alternatives Evaluation Overall Layout of Effluent System

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Town of Holly Springs 50
Wastewater Discharge Alternatives Evaluation & Expansion
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RECLAIMED
PUMP STA
v
i
i
i
TOWN OF HOLLY SPRINGS
ENGINEERING ALTERNATIVES ANALYSIS
DISCHARGE ALTERNATIVES EVALUATION
GRAPHIC SCALE
40 0 N
FIGURE 2-3
UTLEY CREEK WRF
UPGRADED SITE - ALTERNATIVE E-I

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Town of Holly Springs 52
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Legend n.
HOL SPRIN 'M' xrayM Ew,uu.Fc,.namnn
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Engineering Alternatives Analysis Alternative E-2: Lower Utley Creek Discharge
d- Discharge Alternatives Evaluation Proposed Oulfall Route

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Al'1
n
Town of Holly Springs 60
Wastewater Discharge Alternatives Evaluation & Expansion
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2.6 Alternative E-4: Wastewater Reuse
The Town of Holly Springs has implemented a new Reclaimed Water System, which was just
placed into service in the summer 2010. Reuse of treated effluent is an option that could relieve
the quantity of wastewater discharged into the waters of the states via NPDES discharge. An
overview of the current service area is shown in Figure 2-7.
Water reuse systems in the central region of North Carolina are predominately landscape
irrigation -based systems that experience high demands during the hot, dry summer season, and
little to no demands during the cool, wet winter season. To effectively reduce the volume of
NPDES discharge capacity on a year-round basis, commercial and industrial users are a
necessity.
The Town of Holly Springs Reclaimed Water System has been planned as a component of larger
planning initiatives of the Town, including the Comprehensive Land Use Plan and the Secondary
& Cumulative Impacts Master Mitigation Plan (SCIMMP). Both of these documents comprise a
140,11) comprehensive planning program aimed at allowing the Town to develop in a manner that
minimizes adverse environmental impacts and preserves the valuable environmental resources in
the Holly Springs area. Wastewater reuse is only one part of the overall program, which also
encompasses transportation planning, erosion and sediment control, storm water management,
potable water and wastewater planning, and open space and recreation planning.
A Wastewater Reuse Master Plan was developed in 2000 to guide the Town in the phased
construction of its reuse system. The specific objectives of the Master Plan are to support the
overall objectives of the SCIMMP by minimizing actual wastewater discharges, conserving
potable water supplies, and protecting potable water quality. Holly Springs' approach to
wastewater reuse is a part of a broadly focused, balanced planning process intended to conserve
high quality water supply sources as well as to minimize the volume of wastewater discharged.
Holly Springs, while predominately residential, is building an industrial and commercial customer
base, and actively promotes reclaimed water for process and cooling needs as much as practical.
Industrial and cooling water users are less subject to seasonal peaks than irrigation, and
therefore allow for consistent year-round utilization of reclaimed water. These type users will
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accomplish two goals, the minimization of wastewater discharges and conservation of potable
water supply.
The initial Holly Springs Reclaimed Water System was constructed from 2006-2010. This initial
phase, including supply pumps, chlorination, distribution piping and an elevated tank, provides
reclaimed water to a service area north of the UCWRF which includes the Holly Springs Business
Park, Twelve Oaks golf course, and Twelve Oaks residential development. Bulk Water will also
be available at the UCWRF site for contractors, landscapers, and other approved users. Initial
estimates for reclaimed water use have ranged from 90,000 gpd during winter months to 750,000
gpd on peak summer time days.
The Town plans to implement additional phases of Reclaimed Water distribution as economic and
customer demands allow. All of the newer and proposed subdivisions within the Reclaimed
Water Service Area are planned to include "purple pipe" distribution systems for future use. Holly
Springs is committed to maximizing the reclaimed water usage to the extent possible.
Since the Holly Springs' primary reclaimed water customer base at this time consists of ?0114N
residential seasonal users and irrigation systems, implementation of the Reclaimed Water
System will not significantly reduce the NPDES discharge volume. Discharge of the full treated
volume may be required during winter months; however, with the seasonal demand peaking in
summer, the effluent loading on the receiving waters will be significantly reduced during the more
sensitive warm weather months. Still, as a full alternative, wastewater reuse is not considered a
viable alternative at this time and no cost estimate can be provided.
W
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2.7 Alternatives Evaluation & Summary
Potential wastewater management alternatives were developed and evaluated in the preceding
pages. After initial review, Alternative E-4: Wastewater Reuse, and Alternative E-5: "No Action",
were determined not feasible as they are not capable of meeting the project purpose and need.
The present worth costs for the alternatives are summarized in Table 2-9 below.
A review of the present worth costs shows Alternative E-2: Lower Utley Creek Discharge, to be
the most economically and environmentally attractive and feasible alternative. .
Table 2-9
Present Worth Cost Summary
Alternative Capital Cost
Western Wake
Present Worth
Total Present Ranking
Expenses
O&M Cost
Worth
E-1 Cape Fear River $39,739,300
$12,967,400
$7,347,600
$47,086.900 2
Discharge
E-2 Lower Utley Creek $14,577,000
$837,000
$5,224,400
$19.801,400 1
Discharge
E-3 Land Application $88,082,000
$837,000
$5,218,100
$93,300,100 3
E-4 Wastewater Reuse —
$837,000
—
— NTF
Notes:
1) Present worth analysis based on 20 year planning period with a discount rate of 4.875%
2) NTF - Not Technically Feasible for this Project
3) Western Wake Expenses are based upon Partners Cost Estimates provided by the Town, and are
included in the Capital Cost shown
4) Land costs for Alternative E-3 are assumed to be 50% salvage value
The preferred Alternative for the Town's wastewater discharge is Alternative E-2: Lower Utley
Creek Discharge. Table 2-10 summarizes the project elements and impacts of the feasible
alternatives evaluated in this report and the accompanying Environmental Assessment.
Town of Holly Springs
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73

Table 2-12
Alternatives Summary
Preferred
Alternative
Alt. E-2 Lower Utley
Alt. E-1
Cape Fear River
Discharge
Alt. E-3
Land Application
Creek Discharge
Net Present
$19.8 M
$ 47.1 M
$93.3 M
Worth
Phosphorus
0.50 TP
0.75 winter
N/A
Limits, mg/L
0.27 OrthoP
0.50 summer
Nitrogen
5.0
5.0 winter
N/A
Limits, mg/L
3.5 summer
Denitriflcation
No
Yes
No
Filters
Phosphorus
Removal
Yes
No
No
Upgrade
Supplemental
Coagulation &
Yes
Yes
Yes
Carbon Feed
Biosolids
Upgrades
Yes
Yes
Yes
Effluent Pump
No
Yes
Yes
Station
Effluent Line
11,700
35,400
TBD
(LF)
Gravity
Forcemain
Wetland
0.10 temp
0.13 temp
TBD
impacts (ac)
0.06 perm
0.03 perm
Stream Impacts
3 intermittent
3 intermittent
TBD
4 perennial
3 perennial
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