NC0037508_WWTP Expansion Guidance_20060720

North. Carolina Department of Environment and Natural Resources
Division of Water Quality
Michael F..Easley, Govemor
Dennis L. Brobst
Moore County.Public Utilities
P.O. Box 1927::
Carthage, NC28327
Dear Permittee:
Recognizing that many local governments face the need of planning for expansions of wastewater
treatment plants, the Division has developed the enclosed guidance document. The purpose of this
document is to assist local governments in the planning process by summarizing the steps needed
to obtain all the permits necessary for an expansion.
William G. Ross, Jr., Secretary ..
Alan W. Klimek, P.E., Director
July. 20, 2006
Subject: Guidance Document. for WWTP Expansions
Moore County WPCF
Moore County
The Division track s average flows on a calendar -year basis for all permitted facilities. Those
approaching 80 % of the design hydraulic load of the treatment system are encouraged to start the
planning process to address the increasing flows.
The average flow for calendar year 2005 at your facility was 71% of the hydraulic permitted flow.
Please review this document and consider its applicability to your particular treatment system.
If you need more detailed information or assistance identifying the steps needed to address an
expansion, please contact the .NPDES or Planning Units at [phone].
cc:
Sincerely,
4
Matt Matthews
Point Source Branch
Central Files
tiFayetteville Regional Office'/ Surface Water Protection
NPDES file.
1617 Mail Service Center, Raleigh, North Carolina 27699-1617
512 North Salisbury Street, Raleigh, North Carolina 27604
Phone: [phone] / FAX [phone] / Internet: h2o.enr.state.nc.us
An Equal Opportunity/Affirmative Action Employer-50% Recycled/10% Post Consumer Paper
One
Nor thCarolina
aturallf/

Looking Ahead:.planrang• •
For An' Expansion At Your
Wastewater Treatment
Plant
North Carolina Department of Environment, and Natural Resources
Division of Water Quality
Surface Water Protection
July .2006

TABLE OF CONTENTS
BACKGROUND
PURPOSE
SECTION I - EXPANSION PROCESS
A. KEY STEPS
B. NEEDS ASSESSMENT
C. SPECULATIVE LIMITS
D. ENGINEERING ALTERNATIVES ANALYSIS (EAA)
E. _ SEPA REQUIREMENTS
F. NPDES PERMIT MODIFICATION
G. AUTHORIZATION TO CONSTRUCT PERMIT
SECTION R - FACTORS THAT COULD AFFECT EXPANSION
A. ZERO FLOW STREAM
B. STREAM CLASSIFICATION . -.
C. BASIN PLAN RESTRICTIONS
D. ASSIMILATIVE CAPACITY
E. INFLOW AND INFILTRATION
F. IMPAIRED WATERS/303(D) LIST
SECTION III - APPENDICES
A. POTENTIAL SOURCES OF OUTSIDE FUNDING
B. CONTACTS
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Background
According to statistics released in 2005 by the 'U.S. Census Bureau, in 2005 North Carolina was
ranked as the fifth fastest -growing state in the country. Between 1990 and 2000 the state's
population increased by 23 %. Because of this population growth many public wastewater treatment
systems are approaching their design Capacity. The process of obtaining a permit for a wastewater
treatment plant expansion can be lengthy and complicated therefore careful planning is important to
complete the process on time • . -.‘ -
Purpose
The Division has developed this guidance to provide local governments with information describing
the process involved in obtaining approval for a capacity expansion. As a general rule, 2 1/2 years
should be allowed to complete the permitting process. By helping municipal. utility :managers and
other readers understand the process more clearly, this document will: " _ •
• Help Permittees to prepare approvable submittals, submit those at the proper time, and avoid
requests from the DWQ and other regulators for additional information,
• Speed up the review and approval processes for the project, and
• Reduce the time and money they must spend on project planning and regulatory approvals.
The document is divided into" three parts. Section I describes the key steps required for a treatment
plant expansion. Section II describes some of the potential obstacles the utility manager may face
that are outside the "normal" approval 'proeesses. Section III contains the Appendices that provide.
additional information on sources of funding and contacts. . -

Section I. Expansion Process
A. Key Steps
Certain steps must be completed when planning a treatment plant expansion. Figure 1 shows the key
steps in this process in general terms, the usual sequence of the steps, and typical timeframes for
completing each one. As projects will vary, so will the process and. timing.
Figure 1. Key Steps for WWTP Expansion
Obtain
Speculative Limits
Prepare Engineering
Altematives
Analysis
Conduct
Environmental Review,
Obtain FONSI
Obtain NPDES
Permit Modification
es gn WWTP
;improvements-
e n391,1t(is
rOlarissue
B. Needs Assessment
Utility managers must anticipate when wastewater flows will exceed the capacity of their treatment
system and recognize the need to complete an expansion before increasing flows result in permit
violations. An attentive manager monitors indicators such as:
• Long-term increases in wastewater flow
• Expansion of service area
• New phases of development
• Connection of new customers -
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When a utility does not act proactively to address flow increases, the State may prompt it to take
action. The Division tracks yearly average flow for all permitted facilities. Based on these average
`flows the Division can impose sewer moratoriums as per regulation.15A. NCAC 02H .0223, known
as the "80/90" rule. When the average flow of any calendar year is above 80 % of the permitted
hydraulic capacity of the treatment system, the permittee must complete "an approvable engineering
evaluation of its treatment needs": This report must address either the expansion of the treatment
system, the elimination of extraneous flow or reduction of flow by water conservation. Prior to
exceeding 90 % the permitteee must obtain all permits needed for expansion of the treatment system
and submit plans and specifications for the expansion.
The Division encourages any Permittee operating at 65% or more
of its treatment capacity to familiarize itself with the information
presented here and prepare itself for expansion as soon as
realistically possible.
It is also possible that new permit limits or other conditions will
require major facility improvements. While these improvements
may not include expansion per se, much of the process described
here may apply to them as well.
When the . utility determines that an expansion is necessary, it must develop estimates of the
following factors before proceeding to the next step:
80/90 Rule (2H .0223)
80%: Evaluation of needs and
planning completed
90%: Permitting and design
completed
• Future flows
• Rate of growth (time frame for expansion)
• Probable nature of improvements
C. Speculative Limits
Speculative limits are provided to publicly owned facilities to establish performance criteria for the
design of the wastewater treatment plant improvements. Limits are developed based on the
established uses. of the receiving water body, the capacity of the water body to accept the additional
wastewater loads or current management strategies at the time the speculative limits are developed.
Many issues can influence these permit limits conditions: impairment of the stream, over allocation
of loads, or stream classification restrictions (i.e. High Quality Waters). These and other issues that
could affect the development of speculative limits are discussed in Section II.
Modeling is generally required to develop limits for BOD and ammonia. Different modeling tools
are used depending on the complexity of the situation. The NPDES Unit will perform Level B
models, which are simple models. The. Modeling and TMDL Unit is asked to review or perform
complex models. A permittee may opt to perform the modeling of the stream. The DWQ must grant
approval of such modeling propositions.
To obtain speculative limits submit a letter to DWQ's NPDES Unit describing the proposed flow
and discharge location. DWQ will provide speculative limits to' publicly owned treatment works for
up to two flows scenarios per year. Allow 30 to 60 days for issuance of speculative limits. If
complex modeling is required an additional 60 to 90 days may be required.
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D. Engineering Alternatives Analysis (EAA)
North Carolina regulations require permit holders to complete an Engineering Alternatives Analysis
(EAA) for expansions of a wastewater treatment system. The EAA shall include a justification and
demonstration of need for the expected flow volume (15A NCAC 2H.105 (c)(1)). It should also
include a summary of waste treatment and disposal alternatives options that were considered and
.'why the proposed system and proposed alternative were selected (15A NCAC 2H.105 (c)(2)). The
NPDES Unit developed a detailed guidance for the. preparation of EAAs. The document can be
found at http://h2o.enr.state.nc.us/NPDES/documents/EAAGuidance.DOC.
If the project is subject to the State Environmental Policy Act (SEPA) review, the requirements of
the EAA must be folded into. the Environmental Assessment (EA) or Environmental .Impact
Statement (EIS). SEPA applicability and requirements are discussed in the following section. If the
project is funded by the Construction Grants and Loans Section, the EAA requirements shall be
incorporated in the Engineering Report. Guidance for the preparation of the Engineering report can
be found at http://www.nccgl.net/fap/Guidance for Engineering Reports.pdf.
The EAA for a proposed
NPDES expansion must
provide complete justification
for a direct discharge to surface
water and demonstrate that the
direct discharge is the most
environmentally sound cost
effective alternative.
For projects not subject to SEPA, the EAA shall be submitted to
the .NPDES Unit with the permit modification request. • The
NPDES Units will review the EAA. for completeness. A document
that doesn't include all required elements will be returned to the
applicant. The review process.takes 90 to 180 days. Only after the
NPDES Units concurs with the EAA can, the permitting process
proceed. See Part F. NPDES Permit Modification for more
information on the permit modification process..
E. State Environmental Policy Act (SEPA) Review
Prior to submitting a permit application to DWQ's NPDES Unit to 'expand a wastewater discharge
facility, the applicant must determine if the project will require a North Carolina Environmental
Policy Act review. SEPA, as it is commonly referred, requires the State's agencies, such as DENR,
to review and report on the environmental effects of certain activities for which it issues permits.
SEPA is implemented througha comprehensive written description of a project and its impacts in
either an environmental . assessment (EA) or environmental impact statement (EIS). These
documents are meant to disclose the project's direct, secondary and cumulative impacts to the
environment and natural resources, provide an analysis of project alternatives considered, and
describe mitigation for any impacts noted. Both
documents must report on the effects of the, project on
surface and groundwater, floodplains, wetlands, air
quality, land use, wildlife resources, noise, scenic and
recreational areas, shellfish and finfish; forestland,
cultural and historical resources, and toxic substances.
Which document to proceed with depends on the
magnitude of a project's potential environmental
impacts, but public interest could be a factor as s well.
An EA is generally prepared if the project is not
anticipated to produce significant adverse
environmental impacts, if impacts can be mitigated to
level of insignificance, or if the magnitude of impacts is
uncertain. A determination to require an EIS can be
Environmental documentation under
SEPA is generally required for:
• New discharge facilities with a
proposed permitted flow of 500,000
gallons or more per day or producing
an instream waste concentration equal
or exceeding 33 percent during the 7-
day 10-year. low flow conditions
• Expansion of an existing discharge
facility. of 500,000 gallons or more per
day additional flow
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expiration date, DWQ may choose to renew and modify the permit at the same time and so must
have the application to proceed.
When DWQ receives a satisfactory request, the NPDES staff reviews the project proposal and past
documents and prepares a draft permit with the new effluent page. The new permit mayalso include..
special conditions, such as to requiremitigative measures- indentified in the project's SEPA
document. The Division publishes notice of .the draft permit, as with permit renewals, and invites
public .comments for. 30. days. At the end of the comment period, DWQ. considers any comments
received, and issues the permit, if appropriate. The process of modifying a permit usually takes 180
days.
G. Authorization to Construct Permit
An Authorization ,to Construct (ATC) Permit is required prior to constructing or, substantially
modifying a wastewater treatment plant. This includes the addition, deletion, or modification of
equipment, components, or processes at an existing discharging facility that has the potential to
affect the treatment process and also the upgrading or replacing of equipment with a . different
capacity.
The Division's. Construction Grants and Loans Section is responsible for reviewing .and approving
all ATCs that are issued in ,the State of North Carolina. After obtaining: an .NPDES permit for a
capacity .expansion. an ATC permit must be obtained before beginning construction. Torequest an
ATC submit any. application, plans and specifications and all
applicable information. Once .a complete submittal..pacicage is
received the review process can begin. Depending on the time it
takes' for the receipt of additional information, ATCs are typically
issued within 90 calendar days from receipt- of a complete
submittal. The ATC permit does not undergo public review. As
soon as the Permittee receives the ATC permit, it can advertise for
bids on the construction project. Requesting bids before receiving, the
permit is a violation of state regulations. Further, the Permittee runs
the risk that it may have to change its design to get its ATC permit —
after it has requested bids on the unapproved design.
Detailed information about the Authorization To Construct process can be obtained at
http://www.necgl.net/.
After an NPDES permit has
been issued, construction of
wastewater treatment
facilities or additions thereto
shall not begin until final
plans and specifications
have been submitted and
and ATC has been issued to
the permittee.

made from the onset of project planning or at any time during review of an EA:
To be subject to a SEPA review, a project or activity must meet each of the following conditions or
triggers:
1. Require an action by a state agency (issuance of permits);
2. Involve. an expenditure of public money or private use of public land; and
3. Have a potential detrimental environmental effect upon natural resources, public health and
safety, natural beauty, or historical or cultural elements of the State's common heritage [NC
General Statute 113A, sections 1 to 13].
Due to the difficulty of determining a project's potential effect on the environment; DENR has
developed rules (15A NCAC .O1C .0408) toidentify those projects requiring a SEPA document.
According to these rules, the expansion of an existing discharge facility of 500,000 or more gallons
per day additional flow will require preparation of a SEPA document: For a 'description of the SEPA
program and requirements please refer to DWQ's SEPA website: http://h2o.enr.state.nc.us/sepal.
Document Review
DENR has delegated management of SEPA to its agencies according to their permitting authority.
Thus, for wastewater discharge expansion projects, because it has the,primary responsibility, DWQ
will serve as the lead agency. In this role, DWQ is responsible for the scope, objectivity, content and
accuracy of the environmental document. SEPA documents are submitted to DWQ's Planning Unit,
who coordinates DENR agencies review.'
The review time for a SEPA document will vary depending on the magnitude of the project,
sensitivity of natural resources it may impact, the document's overall quality and legal compliance,
and public interest. EA reviews average five months but could take a year or longer. EIS reviews
will generally require a minimum of a year.
If subject to SEPA, permits for the proposed expansion cannot be submitted to DWQ's NPDES Unit
until the EA or EIS review process is deemed completed by the North Carolina_. Department of
Administration's Environmental Clearinghouse (SCH). To proceed to the SCH, the EA or EIS must
first receive a satisfactory review by DENR agencies and applicable DWQ staff.
DENR is currently preparing guidance to assist environmental document preparers. Until this
material is finalized, please refer to DWQ SEPA website http://h2o.enr.state.nc.us/sepa/index.htm
for additional information or contact our SEPA coordinator directly at [phone].
F. NPDES Permit Modification -
A facility's NPDES permit contains the approval for expansion, in the form of a new effluent page,
which authorizes and sets discharge limits for the increased design flow. Thus, an expansion request
requires a major permit modification.
DWQ can modify an NPDES permit only after the State Clearinghouse approves a FONSI for the
project. The request for modification can be in the form of a letter, signed by the same official who
would normally sign the permit renewal application. The letter can refer back to previous documents
— the speculative limits letter, the Environmental Assessment, etc. — for the specifics of the proposal.
In some cases, DWQ will require the Permittee to complete the usual permit application form (Form
2A for large or complex municipal plants). For example, if the permit is within a year of its
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Section II. Factors That. Could Affect Expansions
A. Zero-Flow:Stream . _ Flow design criteria are used by the DWQ to develop water quality based effluent limitations. The
summer 7Q10 (s7Q10) flow and 30Q2 flow are two flow criteria used to determine effluent
limitations. No expansions or new discharges ofoxygen consuming wastes are allowed when the
summer 7Q10 and 30Q2 flows are below 0.05 cfs. If the summer 7Q10 flow is below 0.05 cfs and
the 30Q2 flow is greater than .0.05 cfs the expansion may be allowed if limitations of BOD5 = 5
mg/l,. NH3-N = 2 mg/I and DO = 6 mg/1 protect water quality. standards. Flow characteristics are
usually estimated by the US Geological Survey.
B. Stream .classification
Surface Water. Classifications are designations applied to surface water bodies, such as streams,
rivers and lakes, which :define . the best uses to . be protected .within these waters (for example
swimming, fishing, drinking water supply) and carry with them an associated set of water quality
standards to protect those uses. Surface water classifications are one tool that state and federal
agencies use to manage and protect all streams, rivers, lakes, and other surface waters in North
Carolina.
Many of the classifications, especially those designed to protect drinking water supplies and certain
high quality `waters; have protection rules which regulate activities, such as wastewaters discharges
that may impact surface water quality. No expansions of domestic wastes are allowed on waters
classified as $A, WS I & II, or ORW to preserve the uses of these waters. Other classifications may
require the discharger to meet stringent limits. More information on stream classification can be
found at http://h2o.enr.state.nc.us/csu/index.htm.
C. Basin Plan Restrictions
Basinwide water quality plans are•prepared by the DWQ for each of the 17 major river basins in.the
state. Preparation of a basinwide water quality plan is a five-year process. Basinwide planning is a
tool to identify water quality problems and restore full use to impaired waters, identify and protect
high value resource waters, and protect unimpairedwaters,. yet allow for reasonable economic
growth.
A basin plan presents water quality initiatives and recommendations for each subbasin in a river
basin. The recommendations presented in the basin plan will be implemented when developing a
permit or evaluating a permit expansion request. More information on the Basinwide Planning
Program can be found at http://h2o.enr.state.nc.us/basinwide/basinwide wq planning.htm
D. Assimilative Capacity
The DWQ utilizes analytical models to determine the maximum amount of wastewaterr that can be
discharged into a body of water and still meet the water quality standards. If such study shows that
the receiving stream can't assimilate additional oxygen consuming wastes, expansion of an existing
discharge is not allowed.

E. Inflow & Infiltration (1/1)
In some instances high flows are attributed to infiltration and inflow (I/1). The amount of I/I present
in the collection system shall be calculated and compared to EPA's excessive I/I criteria. When
excessive I/I is present further evaluation is necessary for economic feasibility of reducing the I/I.
Generally, request for additional flow will not be permitted if the facility is experiencing excessive
I/I.
F. Impaired Waters - 303'(d) List and TMDLs
Section 303(d) of the Clean Water Act (CWA) requires states to develop a list of waters not meeting
water quality standards or which have impaired uses. Listed waters must be prioritized, and a
management strategy or total maximum daily load (TMDL) must subsequently be developed for all
listed waters.
The DWQ evaluates waters. for multiple uses in each basinwide management plan. These uses
include aquatic life support, primary and secondary recreation, fish consumption, water supply, and
for coastal waters, shellfish harvesting. If data indicate that any one of these is impaired, the water
body is included in the Section 303(d) list. _Waterson .the 303(d) list are scheduled for additional
study and/or development of a TMDL.
A TMDL is a calculation of the maximum amount of a pollutant that a waterbody can receive and
still meet water quality standards, and an allocation of that amount to the pollutant's sources. An
implementation plan outlines the steps necessary to reduce pollutant loads in,a certain body of water
to restore and maintain designated uses. The development of TMDLs and implementation plans are
often the best method to improve water quality. Federal regulations prohibit the addition of certain
new sources and new discharges of pollutants to waters listed on the North Carolina 303(d) List until
a TMDL is established. The terms and conditions of the TMDL will be followed at the time a
request for speculative limits is made. More information on the TMDL Program can be found at
http://h2o. enr. state.nc. u s/tmd1/

Section III. Appendices
A. Potential Sources of Outside Funding
Division of Water Quality, Construction Grants and Loans Section
The Construction Grants & Loans Section has funds available for the construction of wastewater treatment and
transmission facilities. The .Clean Water State Revolving Fund is a low interest federally funded program. The
Wastewater Reserve Account has several low interest loan and/or grant accounts available to fund wastewater collection,
treatment works, and emergency situations. Currently only loan funds are available through the various programs.
In order to receive funding through the Clean. Water State: Revolving Fund an owner must be on the State's priority list. -
To get on the list a letter of ''request should be submitted prior . to ` March 315t each year.
To receive funding through the Wastewater Reserve account an application and all supporting information should be
submitted on or before March, 315t and September 30th ' of each year. More information can be found at:
http://www. ncc gl. net/.
USDA Rural Development in NC
Rural Development announces availability of money for its programs in the Federal Register, through ,a Notice of Funds
Availability (NOFA). Each NOFA lists the application deadlines; eligibility requirements and places you can get help
applying. More information can be found at: http://www.rurdev.usda.gov/nc/.
NC Department of Commerce - Community Development Block Grant
NC Department of Commerce through the Division of Community Assistance administers the NC Small Cities
Community Development Block Grant. All NC small cities are eligible except entitlement cities that get funds directly
form HUD. There are. 7 Program Categories: Community Revitalization, Scattered. Site. Housing, Infrastructure,
Economic Development, Housing Development, Urgent Needs, Capacity Building. More information can, be found at'
their website: http://www.dca.commerce.state.nc.us/cdbg/.
Clean Water Management Trust Fund (CWMTF)
CWMTF makes grants to local governments, state agencies and conservation non -profits for projects that specifically
address water pollution problems. CWMTF accepts grant applications during 2 cycles. The cycles close June 1 and
December 1. More information can be found at the website: http://www.cwmtf.net/. -
Appalachian Regional Commission
ARC awards grants and contracts from funds appropriated to. the Commission annually by Congress to nonprofit
organizations for projects that further the four goals identified by the Commission:
1. Increase job opportunities and per capita income to reach parity with rest of nation.
2. Strengthen the capacity of the people of Appalachia to compete in the Global economy.
3. Develop and improve the Appalachia's infrastructure to make the region economically competitive.
4. Build the Appalachian Development Highway System to reduce Appalachia's isolation.
Local development district serving the county the project is located in may be able to provide guidance on a project's
eligibility for funding and assistance in preparing the grant application.
North Carolina Rural Economic Development Center
The Rural Economic Development Center offers the following -water and sewer grant programs: North Carolina
Economic Infrastructure Program, Supplemental Grants Program, Capacity Building Grants Program, and Unsewered
Communities Grant Program. Local governments is rural counties are eligible.
Applications are taken on a rolling basis, first -come, first -serve. An applicant must first submit a pre -application.. More
information can be found at the website: http://www.ncruralcenter.org/. -

B. Contacts
Division of Water Quality
NPDES Program (NPDES East and West Units)
1617 Mail Service Center, Raleigh, NC 27699-1617
919-733-5083
Website: http://h2o.enr.state.nc.us/NPDES/
Modeling and TMDL Unit
1617 Mail Service Center, Raleigh, NC 27699-1617
919-733-5083
Website: http://h2o.enr.state.nc.us/tmdll
Community Development Block Grant
Vanessa Tunstall
Senior Development Specialist
[phone]
Website: http://www.dca.commerce.state.nc.us/cdbg/
email: [e-mail]
Planning Section
State Environmental Policy Act (SEPA) Program
DWQ Planning Branch
1617 Mail Service Center, Raleigh, NC 27699-1617
919-733-5083
Website: http://h2o.enr.state.nc:us/sepa/index.html
Construction Grants and Loans Section
1633 Mail Service Center, Raleigh, NC 27699-1633
919-763-6900
Website: http://www.nccel.net/
Other Agencies
Clean Water Management Trust.Fund _
1651.Mail Service Center, Raleigh, NC, 27699-1651.
[phone]
Website: http://www.cwmtf.net/
North Carolina Rural Economic Development Center
Thomas W. Lambeth, Chairman
Billy Ray Hall, President
4021 Carya Drive
Raleigh, NC 27610
Website: http://www.ncruralcenter.org/index.asp
USDA Rural Development in NC
Community Programs Division, Roger B. Davis, Director
4405 Bland Road .
Raleigh, North Carolina 27609
919-873-2061
919-873-2075(FAX)
Website: http://www.rurdev.usda.eov/nc/ -
email: [e-mail]
Appalachian Regional Commission
Sara Stuckey, Appalachian Program Manager
4313 Mail Service Center
Raleigh, NC 27699-4313
919-733-2853
email: mailto: sstuckey @nccommerce.com
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