NC0039594_Plan of Action_20010621

NPDES DOCUWENT SCANNING: COVER SHEET
NC0039594
Maiden WWTP
NPDES Permit:
Document Type:
Permit Issuance
Wasteload Allocation
Authorization to Construct (AtC)
Permit Modification
Complete File - Historical
Engineering Alternatives (EAA)
Correspondence
Owner Name Change
P74f4 oP f 4.,
Instream Assessment (67b)
Speculative Limits
Environmental Assessment (EA)
Document Date:
June 21, 2001
This document is printed on reuse paper - ignore any
coritent on the reYerse side

PhO e-evo4 NC0039sqi
TOWN OF MAIDEN
NORTH CAROLINA
28650
P.O. BOX 125 • [phone]
FAX [phone] • TDD 800-735-2962
June 21, 2001
NCDENR
NPDES Unit
1617 Mail Service Center
Raleigh, NC 27699-1617
RE: WASTEWATER MANAGEMENT PLAN
To Whom It May Concern:
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Enclosed is the wastewater management plan for the Town of Maiden which was required by our NPDES permit. Per the
permit, the following items were to be included: Facility Needs Assessment and Rehab/Optimization Strategy. The
following is an outline of steps the Town has taken or will be taking.
1. Facility Needs Assessment. The Town contracted with McGill & Associates to perform a Needs Assessment on
the wastewater treatment plant. This report was completed and presented to Town Council in June. Copies of
the report are included for State review. The report covered the inflow/infiltration problems the Town is
experiencing, clarifier skimming device repairs, and the sludge storage issues. The study provided three
alternatives to address these problems. The Town is currently moving forward with the recommended alternative
(#2) from the study. As the Town moves forward with these plans over the next FY budget, letters to keep the
State NPDES Unit up-to-date will be sent.
2. Clarifier skimming device. One of the two skimming devices on our treatment modules has already been
replaced with a new stainless steel version. Jim Meyers & Sons (Charlotte, NC) designed the new version and
installed the device. Our next budget (FY 2001-2002) includes money to replace the second one if the
modifications to the plant (Needs Assessment Altemative #2) aren't started.
3. Inflow/Infiltration. Our next budget (FY 2001-2002) includes money for the following areas to begin to address
the Town's inflow/infiltration problems: $18,000 to have flow monitoring performed on the system to determine
areas where the inflow is coming from, $26,100 to purchase a camera system to view and determine repairs on
lines which have been identified as problem areas, and $26,000 for a new position on the Sewer line crew which
will enable the Town to improve the collection system preventative maintenance program.
If there are any questions or comments concerning the plan, please give me a call at [phone].
Best reg
CC; z�`'C
Michael Lingerfelt
WWTP Superintendent
Enclosure

PRELIMINARY ENGINEERING REPORT
MAIDEN WASTEWATER
TREATMENT PLANT
MAIDEN, NORTH CAROLINA
DOUGLAS CHAPMAN, P.E.
EASSOCIATES
Engineering • Planning • Finance
222 Union Square, Suite 306
Hickory, North Carolina 28601
MAY, 2001
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Introduction
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Overview
he Town of Maiden is located in the foothills of North Carolina, in southern
Catawba County. The Town owns and operates a wastewater collection and
treatment system primarily serving the Town's incorporated areas. Wastewater from the
system is treated at the Town's wastewater treatment plant, located on Clarks Creek, at the
end of West Finger Street.
The wastewater plant, built in 1981, has a permitted capacity of 1.0 million gallons per day
(MGD). The plant utilizes the activated sludge method of biological treatment, with
aeration provided by pure oxygen. The plant, which discharges into Clarks Creek,
currently has a current average daily flow of 0.3 MGD.
Purpose of this study
ue to several factors which affect plant performance and compliance, the North
Carolina Department of Environment and Natural Resources, Division of Water
Quality (DWQ) has required that Maiden perform a needs assessment of the treatment
plant capacity and operations. The purpose of this report is to analyze the Maiden
wastewater treatment plant process, operation, projected wastewater flows, and proposed
treatment technologies. This analysis will also identify possible funding sources, and
includes a financial analysis of the proposed improvements.
McGi11IATES
Page 1 Engineering • Planning ■ Finance

Current Wastewater Flows
The Town of Maiden's current wastewater flow is approximately 95% domestic,
with only 5% being industrial. For the purposes of this report, all influent and
effluent data, including parameters such as biological oxygen demand (BOD), total
suspended solids (TSS), total suspended residuals (TSR) and flow, have been taken from
monthly treatment plant reports from January 1999 through December 2000. During this
period the average daily flow was 0.361 MGD.
Based on conversations with Town staff, and review of monthly reports, the wastewater
collection system has a significant amount of infiltration and/or inflow. Daily flow surges
during wet weather periods have been recorded as high as 4.7 times the average daily flow.
Also, the daily flow total exceeded the permitted limit of 1.0 MGD, on 8 separate days
during the two-year study period. In contrast, during the last six (6) months of the year
2000, which had abnormally dry weather, the average daily flow was only 0.25 MGD, or
0.111 MGD lower than the two-year average. The Town is implementing a program to
address infiltration/inflow problems, including clearing of right-of-ways, visual
inspections, and smoke testing. Despite Maiden's efforts to reduce this problem, it still
exists.
With flows during the last six months of the study period 30% below the two-year average,
the current average daily flow is assumed to be 0.30 MGD, for the purposes of this report.
Also, the average influent concentrations of selected constituents are assumed to be as
follows: BODS — 225 mg/land TSS — 300mg/1.
0. McGill
ASSOCIATES
Page 2 Engineering ■ Planning ■ Finance

Existing Wastewater Treatment Plant
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onstruction of the existing wastewater treatment plant was completed in 1981. The
.. plant has a rated design and permit capacity of 1.0 MGD. Treatment of wastewater
entering the plant is accomplished by the activated sludge process. The plant has been
adequately maintained since construction, with only minor equipment being replaced
Flow from the collection system enters the plant at the headworks, where screenings are
removed by a mechanical bar screen. Following screening, grit is removed from the flow
through an air lift and cyclone separator. Screenings and grit are discharged into 50 gallon
containers, lifted out of the headworks structure, and discarded into a dumpster nearby.
The dumpster is periodically emptied, and residue is transported to the Catawba County
Solid Waste Landfill. Following preliminary treatment, wastewater is pumped to the
treatment modules by two dry well centrifugal pumps. The pumps are located in a small
prefabicated steel structure, which is 27-feet deep, adjacent to the headworks.
From the influent pump station, wastewater flows to two treatment modules, each with a
treatment capacity of 0.5 MGD, that operate parallel to each other. The treatment modules
utilize pure oxygen for aeration of the wastewater. Liquid oxygen is delivered from a
chemical supplier, and stored on site. As needed, liquid oxygen is vaporized to form
gaseous oxygen, which flows independently to the two modules. Aeration is accomplished
through a two -stage process, with wastewater then flowing to a final clarifier. Treated
wastewater is disinfected with chlorine gas, and is discharged to Clarks Creek by gravity.
The plant is designed for biosolids (sludge) to be wasted as needed to a digester, which is
also aerated with pure oxygen. Each treatment module contains the two stages of aeration,
clarifier, chlorine contact basin, and sludge digester in a single 58'-6" diameter round
concrete structure.
Sludge drying beds are available for thickening of waste sludges prior to disposal, but are
used only for drying of water plant residuals. Liquid sludge is hauled to and disposed of at
the Regional Compost Facility, in Hickory. The compost facility is jointly owned by
McGill
ASSOCIATES
Page 3 Engineering ■ Planning ■ Finance

Existing Wastewater Treatment Plant
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several local governments; Hickory, Conover, Catawba County, and Newton. Maiden
disposes of waste in the facility under capacity owned by Catawba County.
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The existing facility has a number of areas where improvements can be made. First, to
reduce the risk of confined space entry and potential damage due to flooding, the existing
influent pump station could be replaced with submersible pumps mounted in a precast
concrete wet well. Second, the existing sludge digesters, at design flow, only provide
approximately 10 days of sludge storage, well below the 30 days of liquid sludge storage
required by state regulations. Therefore a new biosolids storage and processing unit is
needed at the plant.
Currently, only one treatment module is used to treat wastewater, with the remaining
module used for sludge storage. Consequently, the plant has an effective treatment
capacity of 0.5 MGD. With the plant essentially operating at half the rated capacity, the
treatment capacity of 0.5 MGD was exceeded 93 times, or 13.5% of the days from January
McGill
ASSOCIATES
Page 4 Engineering ■ Planning ■ Finance

Existing Wastewater Treatment Plant
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1999 to December 2000. Furthermore, during the study period the plant exceeded 0.4
MGD, or 80% of the 0.5 MGD effective capacity, on average, one out of every three days.
Following review of the data, it appears that flow surges are related to infiltration and/or
inflow. Two items that amplify the flow problem are lack of flow equalization prior to the
treatment module, and constant speed influent pumps, thus causing intermittent and
increased flow to the treatment system. Finally, the existing chlorine contact basins were
designed for 15 minutes of detention time, half of the current standard. These items, in
addition to the age of the treatment plant equipment, are the major factors contributing to
the poor performance of the facility.
Though the treatment plant has been out of compliance on several occasions in the past two
years, operators do a commendable job at meeting discharge permit limits. Most of the
violations appear to be a result of excessive flow either overloading the plant, or "washing
out" the established biological mass in the clarifier and aeration basin. Considering the time
necessary to plan, design, and construct the proposed improvements, an interim solution is
needed to improve compliance. The solution that is simplest and most cost effective to
implement is operation of both treatment modules for treatment of influent wastewater.
Currently the clarifier in one basin is inoperable due to solids removal mechanism failure.
This mechanism is scheduled for repair in June, 2001. Following this repair, both treatment
modules will be capable of accepting and treating influent wastewater. The difficulty with
operating both modules is lack of nutrient loading during dry weather periods. With the low
detention time of the pure oxygen process, operating both treatment modules will remain
difficult with the fluctuating flow due to infiltration/inflow. Another problem with operating
both modules is lack of adequate sludge storage, which is only 10 days at design capacity.
Such operation will require more operator attention for sludge flow control, manual
decanting of supernatant, drying bed operation, and residual hauling to the regional compost
facility. Finally, operation of both modules will increase operating cost due to higher liquid
oxygen demand from multiple basin operation.
McGill
ASSOCIATES
Page 5 Engineering • Planning ■ Finance

Projected Wastewater Flows
aiden is located in one of the fastest growing areas of North Carolina. The
current population of 3,282, taken from 2000 census data, is an increase of
27.5% over the 1990 population. Based on the Maiden 2020 Vision, the
population is expected to increase another 52%, and exceed 5,000 by the year 2020.
As a part of this report, we have identified several areas for industrial/commercial growth,
as well as areas of residential growth. A map of the current Town limits, and targeted
growth areas is included as Appendix A.
Industrial and commercial growth has been identified for areas currently zoned as such in
the vicinity of US 321, Startown Road, West Maiden Road, and Prison Camp Road. These
areas consist of approximately 2,000 acres, which if growth occurred according to the
Maiden 2020 Vision Plan and 40% were developed with 12 employees per acre, would
generate 9,600 jobs and consequently 0.24 MGD in wastewater flow by the year 2021.
Residential growth areas for the wastewater system have been identified to the south near
Glen Oaks Country Club, and to the north near the US 321 Business corridor. Wastewater
flows, from this 3,000 acres, developed at a rate of 50% and one dwelling unit per two
acres, are estimated at 0.27 MGD in the next 20 years. Development at this rate, 750
dwelling units, at a density of 2.6 persons per household, will result in a population
increase of 1,950. When added to the current population of 3,282, closely mirrors
population projections of 5,000 in the Maiden 2020 Vision Plan.
In 1996, the Town of Maiden entered into an agreement with Lincoln County to provide
wastewater collection and treatment to an industrial park located in northern Lincoln
County. Subsequently, the Town's collection system was extended to serve the area. In
the agreement, Maiden committed to accept and treat up to 0.2 MGD of wastewater from
the industrial park and surrounding areas. Currently there is only one customer in the park,
whose usage is less than 1,000 gpd.
McGill
ASSOCIATES
Page 6 Engineering • Planning ■ Finance

Projected Wastewater Flows
Estimated residential, industrial and commercial growth, when combined with allocations
to the Lincoln County Industrial Park and existing dry weather flows, brings the projected
20-year wastewater flow to 1.01 MGD. Based on an average growth rate of 6.6% over the
20-year period, the wastewater plant will reach 80% of the current permitted capacity in
year 2016. Though the current permitted capacity is sufficient to accept projected growth
for a number of years, infiltration/inflow, limited sludge storage, and aging treatment
equipment warrant the need for improvements to the facility.
McGill
ASSOCIATES
Page 7 Engineering • Planning ■ Finance

Proposed Alternatives
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ollowing a review of the current treatment facilities, the need for improvements to
retct
the treatment process is evident. With the current operation scheme, the plant
cannot adequately treat the permitted capacity of 1.0 MGD. At this time, an expansion of
the permitted flow capacity is not needed, yet improvements must be made to the existing
facility to treat that permitted capacity. Improvements are needed to adequately treat waste
during high flow periods that result from infiltration/inflow, as well as addressing the
sludge management problem, and easing plant operations. The following alternatives will
be evaluated:
1. Upgrade and improve the existing plant facilities.
2. Convert the existing treatment modules to sequencing batch reactors.
3. Constructing an oxidation ditch aeration basin with clarifiers.
MOCIATES
cGill
Page 8 En��ineering ■ Planning ■ Finance

Evaluation of Alternatives
''''12" his section of the report will describe the three alternatives and list the advantages
� and disadvantages of each.
Improvements Common to All Alternatives
ne improvement common to all of these alternatives is replacement of the existing
influent pump station. The station is equipped with non -clog centrifugal pumps
housed in a prefabricated steel structure. The controls and electrical equipment are located
with the pumps in the lower section of the 27-foot deep pump station. Upper sections of
the steel structure have visible rusting and are beginning to leak when the ground water
level is high. The existing pump station dry well will be replaced with a new precast
concrete wet well and submersible, non -clog, centrifugal pumps. The pumps will be
mounted on rails and removable with a mechanical hoist. Electrical equipment and
controls would be mounted in weatherproof enclosures at the top of the proposed pump
station. Therefore, no confined space entry would be necessary. Consequently, with
replacement of the influent pump station, operations will be safer and more reliable. To
improve plant operation, variable speed pumps, or multiple (three) pumps will be installed
to achieve a more consistent pumping rate, and reduce regular flow spikes.
Several other advantages over the existing treatment facilities are common to each of the
three alternatives listed. First, each alternative includes a sludge holding tank to provide
for adequate sludge storage volume, and allow the operators the ability to thicken the waste
residuals by gravity. Additional sludge holding will allow each alternative the ability to
fully utilize the treatment units for activated sludge biological treatment. Second,
increased chlorine contact time for disinfection will be provided with each alternative.
Last, and most importantly, each alternative will improve the plant's ability to treat peak
flows due to infiltration/inflow. The need to reduce wet weather infiltration/inflow is
paramount to the long-term success of the Maiden wastewater system. These peak flow
EMcGill
ASSOCIATES
Page 9 Engineering ■ Planning ■ Finance

Evaluation of Alternatives
provisions will allow the facility to treat intermittent peak flows, for periods of time, and
meet the current permitted limits.
One item common to all the listed alternatives, is the need to remove a portion of the
existing sludge drying beds. Considering the sparse use of the drying beds, any impact of
a 50% reduction in drying bed capacity is minimal.
Alternative 1 - Upgrade and Improve Existing Plant
Facilities
lternative 1 consists of improving the existing treatment system, with no change in
the wastewater treatment process. The combustible gas detection system,
associated alarms and emergency shut -down controls have been inoperable for a number of
years, and need to be replaced. The valves which operate the oxygen feed system and
maintain correct oxygen levels in the aeration stages operate off of oxygen tank pressure,
and have been in service for 20 years. These valves will be replaced with electric valves
that are controlled by an electric control signal.
Both clarifiers have a rotating, sludge scraper and scum removal mechanism that is in need
of repair and/or replacement. The Town staff has engaged the services of an equipment
supplier to repair the scum removal portion of one of the two mechanisms. As part of the
proposed plant upgrade, the two mechanisms will be completely rehabilitated to improve
sludge and scum removal.
With both treatment modules in operation, the existing sludge digester volume equates to
approximately 10 days of storage at a solids concentration of 2%. Therefore, a new sludge
holding basin, with 30 days of storage will be required with associated piping and diffused
aeration. The existing sludge digester chambers within the treatment modules will be
converted to additional chlorine contact basins to achieve a 30 minute contact time for
disinfection.
McGill
ASSOCIATES
Page 10 Engineering ■ Planning ■ Finance

Evaluation of Alternatives
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The above improvements and modifications will allow both 0.5 MGD treatment modules
to operate on a continuous basis. For the existing pure oxygen, activated sludge process to
effectively treat wastes over a flow range substantially higher than 1.0 MGD, an
equalization basin will be required. The equalization basin, with a capacity of 500,000
gallons, will balance intermittent peak flows, while maintaining a more manageable
constant flow to the treatment units.
The following is a site layout of alternative 1:
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PROPOSED SHE PLAN — ALTERNATIVE 1
The estimated cost for this alternative is $1,835,600, and will allow the plant to adequately
treat the permitted flow of 1.0 MGD. A detailed cost estimate is provided in Appendix B.
McGill
ASSOCIATES
Page 11 Engineering • Planning ■ Finance

Evaluation of Alternatives
In addition to increasing the facility's capacity to 1.0 MGD, by simply improving the
existing equipment reliability and operation flexibility, the plant upgrade will take place
with minimal interruption to plant operations. Also, these improvements will allow the
plant to assimilate intermittent peak influent flows and provide for adequate sludge storage
and handling to meet current State standards.
This alternative has several disadvantages which affect long-term operations of the
wastewater treatment plant. The pure oxygen process has a higher operational cost, due to
liquid oxygen purchases, as well as more complex equipment to maintain. Therefore the
20-year present worth value will be greater than that of Alternative 2. Another concern
with the pure oxygen process is it's sensitivity to variations in influent characteristics such
as flow, BOD, solids and nutrient levels. The pure oxygen system provides very little
contact time for the wastewater with the aeration for biological treatment. Therefore,
maintaining a consistent, and compliant effluent quality will continue to present
challenges.
Alternative 2 — Convert Existing Treatment System to
Sequencing Batch Reactor
A , lternative 2 converts the existing treatment modules to sequencing batch reactors
A(SBR). The SBR is a batch process which uses one single basin for aeration and
clarification, and is a variation of the activated sludge process. The wastewater is aerated
and mixed while influent enters the reactor. The influent flow is then directed to the other
reactor using automatic valves. After influent flow ceases to the reactor, mixing and
aeration also cease, and the wastewater is allowed to settle, with solids moving to the
bottom of the reactor during quiescent conditions. After a predetermined period of
settling, the treated water in the upper level of the reactor is removed by means of
subsurface withdrawal. Once a predetermined volume is removed, the reactor is ready to
accept another batch of influent wastewater. This batch treatment process is repeated on a
timed schedule. The plant will operate with two batch reactors, which are setup to receive
McGill
ASSOCIATES
Page 12 Engineering ■ Planning ■ Finance

Evaluation of Alternatives
influent flow on an alternating basis. This alternative uses the existing concrete treatment
modules and modifies these tanks by adding aeration and mixing to produce a modified
activated sludge treatment process.
To allow the existing treatment modules to be converted to sequencing batch reactors, the
existing interior walls, and top slabs of the treatment modules must be removed, and the
outer walls raised 5'-6". Once these basin modifications are made, the two treatment
modules can be utilized as SBRs capable of treating an average daily flow of 1.0 MGD.
By varying the batch cycle times, the SBR is capable of treating intermittent peak flows,
while meeting the permitted effluent limits. This eliminates the need for an influent
equalization basin. However, intermittent, varying effluent flow will result from the batch
process and thereby require a post equalization basin to reduce the size of the proposed
chlorine contact basin, and to avoid surcharging the existing discharge outfall. The new
chlorine contact basin will be constructed, with 30 minutes of detention time, utilizing the
existing chlorination equipment.
A small amount of biosolids (sludge) will be removed from the reactor during each batch.
This waste sludge will be pumped to a sludge holding tank, equipped with diffused
aeration. The sludge tank will be equipped with the necessary piping, such that the
aeration can be turned off, the tank allowed to settle, and relatively clean water decanted to
the influent pump station. The sludge decant process will be manually performed by the
plant operators. The sludge tank will have sufficient capacity to hold 30 days of sludge
production, assuming regular decanting and an average sludge concentration of 2% solids.
The following is a layout of the proposed site for Alternative 2.
McGill
ASSOCIATES
Page 13
Engineering ■ Planning ■ Finance

Evaluation of Alternatives
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PROPOSED SITE PLAN - ALTERNATIVE 2
The estimated cost for this alternative is $1,987,600. Conversion of the existing facility to
a sequencing batch reactor will allow the plant to adequately treat the permitted flow of 1.0
MGD. A detailed cost estimate is provided in Appendix B.
Several advantages can be realized with this option. First, the sequencing batch reactor is
more effective than the pure oxygen system at treating varying influent characteristics.
Thus, plant operations are simplified, and discharge compliance should improve.
Alternative 2 can be more easily expanded in the future, and with less cost than the other
alternatives. The proposed sludge holding tank will be sized so that it can be converted to
an additional sequencing batch reactor for a future capacity of 1.5 MGD, average daily
flow. Conversion to the SBR process, with lower operation and maintenance cost than the
pure oxygen system, has a lower 20-year present worth than either of the other two
alternatives.
McGill
ASSOCIATES
Page 14 Engineering ■ Planning ■ Finance

Evaluation of Alternatives
Also, this alternative has a few minor disadvantages. This alternative has a slightly higher
capital cost that alternative 1, yet is significantly less than alternative 3 discussed later in
this report. This alternative will have minimal impact on current operations allowing the
plant to be fully operational during the construction of the SBR process.
Alternative 3 — Construct an Oxidation Ditch Aeration
Basin with Clarifiers
his final alternative evaluates construction of an oxidation ditch aeration basin,
along with circular secondary clarifiers. The oxidation ditch utilizes three
concentric, oval rings, or zones, to provide biological treatment of the raw wastewater
influent. Each zone, based on detention time, or aeration time, provides a higher level of
biological breakdown. Following this aeration, flow is diverted to secondary circular
clarifiers where the wastewater is allowed to settle under controlled conditions. Treated
effluent is discharged from the clarifiers, and flows to a chlorine contact basin, while waste
sludges are removed from the base of the clarifier. Waste sludges follow two paths, a
portion is returned to the oxidation ditch to maintain a certain level of biological mass in
the treatment basin, while the remainder is diverted to a sludge holding tank.
With the limitations in size and piping of the existing pure oxygen treatment modules,
entirely new concrete structures are required to house the oxidation ditch, as well as the
circular clarifiers, and waste sludge pump station. Aeration for the oxidation ditch will be
accomplished by use of rotating surface aerators, mounted on horizontal shafts. The
clarifiers will be constructed with scum removal equipment, and sludge scrapers to
maximize solids concentration in waste sludge flows. The oxidation ditch system will be
designed for treatment of an average daily flow of 1.0 MGD. With the large surface area
and volume of the oxidation ditch itself, this system is capable of treating wastewater
influent flows in excess of design capacity for intermittent time periods within the existing
discharge permit limits. Therefore, flow equalization is not necessary. In addition, a new
EMcGill
ASSOCIATES
Page 15 Engineering ■ Planning ■ Finance

Evaluation of Alternatives
chlorine contact basin will be constructed, with 30 minutes of detention time, utilizing the
existing chlorination system.
Waste sludges will be removed from the proposed system on a regular basis. The existing
pure oxygen treatment modules will have interior walls removed, as well as top slabs to
prepare the tanks for utilization as sludge holding basins. The basin will be piped for
gravity thickening, and will have diffused aeration. The modified tanks used for sludge
holding basins will have adequate capacity for storage of the sludges produced by the
system over a period of 30 days. As proposed for the other alternatives, the holding basin
will be manually decanted with a solids concentration goal of 2%.
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�\ j LIQUID OXYGEN TANK /
G- 7d1 _ IT_TO REMOVED_ //
-���� !+-'DEB-T-C�--- _ _- __� .__ �— --- %•
PROPOSED SITE PLAN - ALTERNATIVE 3
This alternative has an estimated cost of $3,065,200. Construction of a new oxidation
ditch/clarifier system will allow the plant to adequately treat the permitted flow of 1.0
MGD. A detailed cost estimate is provided in Appendix B.
McGill
Page 16 Engineering • Planning ■ Finance

Evaluation of Alternatives
Several advantages can be realized with alternative 3. Like the SBR process, the oxidation
ditch is more effective than the pure oxygen system at treating varying influent
characteristics. Thus, emergency conditions will occur less often, and discharge
compliance is increased.
Disadvantages also exist with the oxidation ditch alternative. Most significantly is the
higher "up -front" capital cost for this option, coupled with a higher 20-year present worth.
Additionally, the plant cannot be as easily expanded as the SBR process discussed in
alternative 2. This alternative, as shown in the proposed layout, will occupy most of the
usable land area remaining on the site, thus limiting future expansions. Finally, a larger
portion of the sludge drying beds must be removed, to allow for the increased treatment
structure construction.
Summary of Alternatives
he following chart will summarize the proposed alternatives, and their related
costs:
Alternative
Estimated
Capital Cost
Estimated Annual
Operating Cost
20-year
Present Worth
1 - Pure Oxygen
$1,835,600
$428,000
$10,259,850
2 - SBR
$1,987,600
$395,000
$9,609,237
3 - Oxidation Ditch
$3,065,200
$395,000
$10,686,837
Present worth value is used for comparison purposes to evaluate all alternatives in terms of
current dollars. Operating costs listed are for the initial year after start-up, and are
projected to increase at a rate of 4 percent per year for fixed cost, and 8 percent for variable
cost that increase as the flow increases. The present worth analysis is based on a 20-year
study period, and at a discount rate of 5 percent.
McGill
ASSOCIATES
Page 17
Engineering • Planning ■ Finance

Financial Analysis and Funding Alternatives
Financial Analysis
he Town of Maiden Financial Analysis illustrates the funding of wastewater
treatment plant improvements, described earlier in this report as Alternative 2,
which has an estimated total project cost of $1,987,600.
In the preparation of this Analysis, certain assumptions have been made with respect to
conditions which may occur in the future. While these assumptions are reasonable for the
purpose of this report, they are dependent upon future events and actual conditions may
differ from those assumed. The Financial Analysis has been constructed based on financial
trends presented in the Town's audited financial statements, the 2000-2001 annual
operating budget for the water and sewer program, and detailed information and data
provided by the Town. To the extent that actual future conditions differ from those
assumed herein, the actual results may vary from those forecasted.
This Analysis spans a ten year time frame and consists of the following forecasting
components for revenues and expenditures:
• Projections of revenue are based on normal increases for existing levels of
water and sewer sales.
• The expenditure component is divided into operation and maintenance costs,
annual capital outlay and debt service.
The Analysis assumes that water and sewer revenue will increase annually at a predictable
average rate and that program operating expenditures will increase due to inflation. Normal
capital outlay is addressed annually at $50,000 per year over the ten year period. The
capital required for the wastewater treatment plant improvements is assumed to be
acquired through financing.
McGill
ASSOCIATES
Page 18 Engineering ■ Planning ■ Finance

Financial Analysis and Funding Alternatives
The anticipated cash flow requirements will be accomplished without expenditures
exceeding revenues. Also, an important goal of the Analysis is to ensure an unappropriated
fund balance of at least 10% of annual revenues is maintained. A copy of the Financial
Analysis is included in Appendix C.
Funding of the Proposed Improvements
he Financial Analysis prepared for the project assumes that funding is secured from
the State Revolving Loan program at the market interest rate, as this is the most
conservative approach upon which to base the financial assumptions and the State's
Revolving Loan programs are worthy funding alternatives for the Town. The necessary
cash flow has been demonstrated in the Financial Analysis and the debt service payments
appear to be feasible. The nature of the improvements justify the 20 year term assumed for
the debt repayment and the project would be eligible for either the regular or the low
interest program. Applications for either program are subject to the State's priority rating
procedures. The low -interest program is more competitive and the demonstration of critical
health need is essential to success. The next application deadline is September, 2001.
Documentation of critical need generally requires time and the applicant must receive a
high priority rating before the application can be considered for funding. Further, the
applicant must demonstrate "readiness to proceed", which means the plans for the project
must have achieved a certain level of completion in order to be successful.
Borrowing capital from private sources is also a viable option for the Town. This can be
accomplished by either installment debt or revenue bonds. In this case, the installment debt
option may be preferred, providing that debt service payments based on an amortization
period that does not exceed 15 years is feasible for the Town. The interest rates will be
quite comparable or even lower than those offered by the State Revolving Loan program.
OMeGill
ASSOCIATES
Page 19 Engineerinz • Plannin�� ■ Finance

Financial Analysis and Funding Alternatives
At this point in time, potential grant resources for the proposed wastewater treatment plant
improvements are quite limited. Federal grant resources are limited principally to the Rural
Development, USDA programs. These funds are competitive and are linked to the relative
financial status of the population of the applicant local governments by family income
levels and water and sewer rates. The grant funds are consumed early in the federal fiscal
year, which begins in October, therefore applications must be initiated well in advance of
these annual appropriations. Further, the grants are complemented with accompanying
loans. Since the loans are made by way of general obligation bonds, the applicant must
have a successful referendum in North Carolina.
The North Carolina Rural Center's Supplemental Grant program also represents a potential
source of grant funds; however, the awards may not exceed $400,000. Also, as Catawba
County is a Tier 5 County, the probability of receiving grant funds from this resource is
very slight. The potential of funding from the High Unit Cost program is also remote,
since the grant resources will likely be exhausted with the current round of applications.
The State is currently attempting to find a permanent source of grant funds for water and
sewer infrastructure. Therefore, funding similar to the High Unit cost program may be
available in the near term.
The final mix of potential grant and/or loan resources should be carefully considered by the
Town and decisions made to pursue various funding alternatives after full evaluation of the
Town's objectives, costs and benefits.
McGill
ASSOCIATES
Page 20 Engineering • Planning ■ Finance

4
9
Proposed Implementation Schedule
nitiating a project such as this one often takes a considerable amount of time. Prior
to beginning design, the owner must determine the best method of financing, and
secure the funds. Therefore, the following schedule outlines the time necessary for the
various stages of project completion.
Interim Revisions to Existing Facility
Repairs to Existing Clarifier Mechanism 1 month
Revise Operations to Activate Both of the Existing
Reactors for Treatment of Raw Influent
2 months
Proposed Improvements
Design Proposed Improvements 7 months
Permitting and Approvals 3 months
Bidding and Award 2 months
Construction of Proposed Improvements 12 months
As the schedule indicates, design, approval, and construction of the proposed
improvements is a 24-month process, following the decision to proceed with the project,
and authorization of design.
0McGill
ASSOCIATES
Page 21 Engineering ■ Planning ■ Finance

Summary
his report has evaluated the performance of the existing pure oxygen treatment
I facility, the impact of wet weather flow infiltration/inflow on the hydraulic
capacity of the existing plant, and evaluated treatment options for wastewater treatment
plant upgrade and expansion, which affect performance, permit compliance, and future 20-
year projected flow requirements.
Infiltration/Inflow
First, and most importantly, infiltration/inflow within the wastewater collection system must
be reduced. During the study period, wet weather flows have been as high as 5 times current
dry weather flow. Most of the compliance, and some of the operational problems are a direct
result of infiltration/inflow. The Town is currently developing a program to address
infiltration/inflow problems, including clearing of right-of-ways, visual inspections, and
smoke testing. Though the improvements proposed in this report will aid in the treatment of
high flows, the infiltration/inflow problem must be addressed. McGill Associates
recommends that the Town increase the efforts currently being made to reduce
infiltration/inflow in the wastewater collection system. A study should be performed if not
already undertaken to identify segments of lines that contribute significantly to
infiltration/inflow, and an associated capital improvement plan should be developed, which
will prioritize projects, and include an implementation and cost schedule.
Current Plant Operations
Next, plant operations, commendable as they are, could be altered as a potential method to
increase regulatory compliance. We recommend that both treatment modules of the
existing plant be utilized for treatment, when the average daily flow is sufficient to support
both modules. This change in operations may increase costs associated with pure oxygen
aeration. Also, operation of both modules will drastically limit the sludge holding capacity
within the system. Reduced biosolids capacity would require additional operator attention,
0. McGill
ASSOCIATES
Page 22 Engineerina • Piannina ■ Finance

Summary
and should only be implemented for a brief period of time, while permanent improvements
are planned, designed, and constructed.
Technical Alternatives/Recommendations
Finally, this report has evaluated several available technical and financial alternatives, for
treatment and construction of wastewater facilities for the Town of Maiden. These
alternatives include (1) the existing pure oxygen operations, (2) sequencing batch reactors,
and (3) oxidation ditch/clarifier system.
Alternative 1, even with the proposed flow equalization basin, has much less detention
time for aeration and clarification, and therefore is more sensitive to peak flows resulting
from infiltration/inflow than Alternatives 2 and 3. It will also be much more difficult to
add treatment for biological nutrient removal to Alternate 1, if future permit changes
warrant such a change.
Expansion costs in the future to increase hydraulic capacity or provide nutrient removal
will be much less with the sequencing batch reactor than either of the other two
alternatives, due to its modular design and alternating batch cycles. Also, Alternate 2
adjusts to wide variations in flow and provides adequate treatment for waste water systems
experiencing heavy loads during wet weather conditions. Treatment takes place in one
basin requiring limited equipment to aerate and decant waste flows during each batch
cycle, resulting in less operator attention than most conventional activated sludge plants.
This alternative provides the lowest present worth value.
Alternative 3 provides essentially the same benefits in design for treatment and flow
equalization as Alternative 2 but offers limited plant expansion options for future growth
due to site constraints, cost and construction requirements.
0. McGill
ASSOCIATES
Page 23 Engineering ■ Planning ■ Finance

Summary
Alternative 2 appears to offer the most cost effective solution for plant expansion, flow
equalization and treatment compliance while dealing with the infiltration/inflow in the
collection system. Additionally the 1.0 MGD sequencing batch reactor will meet the
projected wastewater flow requirements based on population projections outlined in the
Maiden 2020 Vision Land Development Plan.
Based on the aforementioned factors, McGill Associates recommends that the existing
treatment system be converted to a sequencing batch reactor (SBR) process. Knowing that
the process to secure funding could be time consuming, we recommend that the Town
begin the design and approval process of the proposed improvements, to help expedite the
project.
McGill
ASSOCIATES
Page 24 Engineering ■ Planning ■ Finance

APPENDIX A
TARGETED GROWTH AREA MAP
McGill
ASSOCIATES
Page 25 Engineering ■ Planning ■ Finance

TOWN LIMITS
RESIDENTIAL GROWTH
INDUSTRIAL GROWTH
LINCOLN COUNTY
INDUSTRIAL PARK _
ARGETED GROWTH AREAS
WASTEWATER SYSTEM
TOWN OF MAIDEN
McGill
u - ASSOCIATES
ENGINEERING • PLANNING • FINANCE
222 UNION SQUARE • HICKORY, NORTH CAROLINA • 28601

APPENDIX B
PRELIMINARY COST ESTIMATES
EMcGill
ASSOCIATES
Page 27 Engineering ■ Planning ■ Finance

PRELIMINARY COST ESTIMATE
MAIDEN WASTEWATER TREAMENT PLANT - ALTERNATIVE 1
MAIDEN, NORTH CAROLINA
ITEM
UNITS
QUANTITY
UNIT PRICE
TOTAL COST
1
Mobilization
LS
3%
N/A
$39,500
2
New Influent Pump Station
LS
1
$150,000
$150,000
3
Demolition of Pump Station
LS
1
$20,000
$20,000
4
Treatment Equipment Repairs
LS
1
$180,000
$180,000
5
Flow Equalization Basin
CY
420
$500
$210,000
6
Clarifier Equipment Repairs
LS
1
$130,000
$130,000
7
Chlorine Contact Basin Conversion
LS
1
$40,000
$40,000
8
Chlorine Equipment Modifications
LS
1
$10,000
$10,000
9
Yard Piping
LS
1
$75,000
$75,000
10
Site Work
LS
1
_
$100,000
$100,000
11
Demolition of Sludge Beds
LS
1
$50,000
$50,000
12
Sludge Holding Basin
CY
350
$500
$175,000
13
Sludge Holding Equipment
LS
1
$100,000
$100,000
14
Electrical
LS
1
$175,000
$175,000
15
Miscellaneous Metals
LS
1
$50,000
$50,000
SUBTOTAL
$1,504,500
Contingencies (10%)
$150,500
Design Engineering
$112,900
Construction Administration
$52,700
Administrative
$15, 000
TOTAL PROJECT COST
$1,835,600
McGill
ASSOCIATES
Page 28
Engineering ■ Planning ■ Finance

PRELIMINARY COST ESTIMATE
MAIDEN WASTEWATER TREAMENT PLANT - ALTERNATIVE 2
MAIDEN, NORTH CAROLINA
ITEM
UNITS
QUANTITY
UNIT PRICE
TOTAL COST
1
Mobilization
LS
3%
N/A
$43,000
2
New Influent Pump Station
LS
1
$150,000
$150,000
3
Demolition of Pump Station
LS
_
1
$20,000
$20,000
4
Extend Treatment Basin Walls
CY
150
$600
$90,000
5
SBR Equipment
LS
1
$375,000
$375,000
6
Blower and Control Building
SF
1,200
$40
$48,000
7
Post Equalization Basin
CY
190
$500
$95,000
8
Chlorine Contact Basin
CY
90
$500
$45,000
9
Chlorine Equipment
LS
1
$10,000
$10,000
10
Yard Piping
LS
1
$100,000
$100,000
11
Site Work
LS
1
$75,000
$75,000
12
Demolition of Sludge Beds
LS
1
$50,000
$50,000
13
Sludge Holding Basin
CY
350
$500
$175,000
14
Sludge Holding Equipment
LS
1
$100,000
$100,000
15
Electrical
LS
1
$150,000
$150,000
16
Miscellaneous Metals
LS
1
$100,000
$100,000
SUBTOTAL
$1,626,000
Contingencies (10%)
$162,600
Design Engineering
$122,000
Construction Administration
$57,000
Administrative
$20,000
TOTAL PROJECT COST
$1,987,600
EMcGill
ASSOCIATES
' Page 29
Engineering ■ Planning ■ Finance

PRELIMINARY COST ESTIMATE
MAIDEN WASTEWATER TREAMENT PLANT - ALTERNATIVE 3
MAIDEN, NORTH CAROLINA
ITEM
UNITS
QUANTITY
UNIT PRICE
TOTAL COST
1
Mobilization
LS
3%
N/A
$69,300
2
New Influent Pump Station
LS
1
$150,000
$150,000
3
Demolition of Pump Station
LS
1
$20,000
$20,000
4
Oxidation Ditch Treatment Basin
CY
1,450
$500
$725,000
5
Treatment Equipment
LS
1
$300,000
$300,000
6
Clarifier Basins
CY
370
$500
$185,000
7
Clarifier Equipment
LS
1
$200,000
$200,000
8
Chlorine Contact Basin
CY
90
$500
$45,000
9
Chlorine Equipment
LS
1
$10,000
$10,000
10
Yard Piping
LS
1
$150,000
$150,000
11
Site Work
LS
1
$150,000
$150,000
12
Demolition of Sludge Beds
LS
1
$50,000
$50,000
13
Demolition of Treatment Basins
LS
1
$100,000
$100,000
14
Sludge Holding Equipment
LS
1
$50,000
$50,000
15
Electrical
LS
1
$175,000
$175,000
16
Miscellaneous Metals
LS
1
$150,000
$150,000
SUBTOTAL
$2,529,300
Contingencies (10%)
$252,900
Design Engineering
$177,100
Construction Administration
$75,900
Administrative
$30,000
TOTAL PROJECT COST
$3,065,200
McGill
ASSOCIATES
Page 30 Engineering ■ Planning ■ Finance

cipolot — finAliciayof A C-Ori 0 FA .ffiliOt Wei
)4ei aim J Ct
w t eefti4til
TOWN OF MAIDEN re .46,1;
NORTH CAROLINA
28650
P.O. BOX 125 • [phone]
FAX [phone] • TDD 800-735-2962
June 21, 2001
NCDENR
NPDES Unit
1617 Mail Service Center
Raleigh, NC 27699-1617
RE: WASTEWATER MANAGEMENT PLAN
To Whom It May Concem:
`rbfr6tee' C4i/41140a4,,
Enclosed is the wastewater management plan for the Town of Maiden which was required by our NPDES permit. Per the
permit, the following items were to be included: Facility Needs Assessment and Rehab/Optimization Strategy. The
following is an outline of steps the Town has taken or will be taking.
1. Facility Needs Assessment. The Town contracted with McGiII & Associates to perform a Needs Assessment on
the wastewater treatment plant. This report was completed and presented to Town Council in June. Copies of
the report are included for State review. The report covered the inflow/infiltration problems the Town is
experiencing, clarifier skimming device repairs, and the sludge storage issues. The study provided three
alternatives to address these problems. The Town is currently moving forward with the recommended altemative
(#2) from the study. As the Town moves forward with these plans over the next FY budget, letters to keep the
State NPDES Unit up-to-date will be sent.
2. Clarifier skimming device. One of the two skimming devices on our treatment modules has already been
replaced with a new stainless steel version. Jim Meyers & Sons (Charlotte, NC) designed the new version and
installed the device. Our next budget (FY 2001-2002) includes money to replace the second one if the
modifications to the plant (Needs Assessment Altemative #2) aren't started.
3. Inflow/Infiltration. Our next budget (FY 2001-2002) includes money for the following areas to begin to address
the Town's inflow/infiltration problems: $18,000 to have flow monitoring performed on the system to determine
areas where the inflow is coming from, $26,100 to purchase a camera system to view and determine repairs on
lines which have been identified as problem areas, and $26,000 for a new position on the Sewer line crew which
will enable the Town to improve the collection system preventative maintenance program.
If there are any questions or comments concerning the plan, please give me a call at [phone].
Best reg - 'a
Michael Lingerfelt
WWTP Superintendent
Enclosure

N
Mr. D. A. Freeman, Town Manager
Town of Maiden
P. 0. Box 125
Maiden, North Carolina 28650
SUBJECT:
Dear Mr. Freeman:
DIVISION OF ENVIRONMENTAL MANAGEMENT
June 9, 1978
Permit No. NC0039594
Authorisation to Construct
Town of Maiden
Wastewater Treatment Facilities
Catawba County, North Carolina
Final plans and specifications for the subject project have been reviewed
and found to be satisfactory. Authorization is hereby granted for the construction
of 1.0 MGD wastewater treatment facilities including mechanical screening, grit re-
moval, flow recording and monitoring facilities, influent pumps, dual 0.50 MGD pure
oxygen units with aeration basins, clarifiers, aerobic digesters, and chlorination
facilities, 11,000 gallon liquid oxygen storage facilities, standby power, sludge
drying beds, laboratory facilities and approximately 1,000 lineal feet of 12 and
18-inch effluent outfall.
Landfilling of dried sludge must be in accordance with the North Carolina
Division of Health Services or the Division of Environmental Management requirements.
This is a Class III Wastewater Treatment Plant which requires the operator
in responsible charge to hold a valid Grade III Certificate.
This Authorization to Construct shall be subject to revocation unless the
wastewater treatment facilities are constructed in accordance with the conditions
and limitations specified in Permit No. NC0039594.
One (1) set of approved plane and specifications is being forwarded to you
and one (1) set to the Environmental Protection Agency for review and approval.
Upon review and approval of the plans and specifications the Environmental Protection
Agency will advise the Town of Maiden when to advertise for bids for construction of
this project.
cc: Environmental Protection Agency
Catawba County Health Department
O'Brien & Gere, Inc.
Mr. D. Rex Gleason /
Mr. W. S. Hoffman v
Mr. Coy Batten
Planning and Management Section
Sincerelyypurs ,/
. F. McRorie
Director