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ENVIRONMENTAL ASSESSMENT
FOR CITY OF BURLINGTON
SOUTH WASTEWATER TREATMENT PLANT
PLANT EXPANSION AND PHOSPHORUS REMOVAL FACILITIES
OLSEN ASSOCIATES, INC.
Engineers, Architects, Surveyors
Raleigh, North Carolina
Contract Number 8812.02
April 1989
Revised September 1989

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ENVIRONMENTAL ASSESSMENT FOR
CITY OF BURLINGTON
SOUTH WASTEWATER TREATMENT PLANT
PLANT EXPANSION AND PHOSPHORUS REMOVAL FACILITIES
Applicant: City of Burlington
P. 0. Box 1358
Burlington, North Carolina 27216
Responsible Agency: Department of Environment, Health, and
Natural Resources
Division of Environmental Management
P. 0. Box 27687
Raleigh, North Carolina 27611
[phone]
Prepared By: Olsen Associates, Inc.
P. 0. Box 31388
Raleigh, North Carolina 27622-1388
[phone]
* NOTE: A 201 Facilities Plan Amendment was submitted to the Division
of Environmental Management (Mr. Allen Wahab) in January 1989.
The 201 Amendment was approved through the Clearinghouse and a FNSI
was issued by the U.S.E.P.A. Burlington received a $2,400,000 grant
for modification/replacement of failed I/A facilities and a
-$3,600,000 low interest loan for phosphorus removal facilities for
the 9.5 MGD facility.

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7.
TABLE OF CONTENTS
Page Number
PROJECT NARRATIVE 1
EXISTING ENVIRONMENT 2
NEED 2
ALTERNATIVE ANALYSIS 3
ENVIRONMENTAL CONSEQUENCES 7
MITIGATING MEASURES 7
SECONDARY ENVIRONMENTAL IMPACTS 7

1. PROJECT NARRATIVE
The South Burlington Wastewater Treatment Plant is designed for a
total average daily flow of 9.5 MGD. The activated sludge plant was.
originally constructed in 1970. The plant was expanded in 1982 to its
current capacity, and a powdered activated carbon system (PACT) was
installed. The PACT process was shut down in June 1986, and the plant
returned to conventional activated sludge treatment. This plant is in an
area of Burlington experiencing rapid growth, and it is anticipated that
the capacity of this plant must be increased in the next few years to keep
up with growth. Plans are currently under design to increase the plant
capacity to 12.0 MGD. Currently, the plant flow rate averages 6.5 MGD.
The North Carolina Division of Environmental Management has mandated
a limitation on phosphorus discharged into the receiving waters of the Haw
River in this area affecting the required effluent discharge limits at
this plant. The new phosphorus limit of 2.0 mg/l will take effect
beginning in January 1990.
As a result of an alternative analysis submitted in the March 1989
revision to the 201 Facilities Plan Amendment, it was ascertained that the
modified University of Capetown (UCT) biological process plus a chemical
phosphorus removal back-up system was the least cost alternative.
Essentially, the UCT system will consist of one-( 1) anaerobic tank
(2 hour detention); two (2) anoxic tanks, each at 1-hour detention time;
and one (1) aeration tank to supplement the existing aeration basin
capacity for a total of 8 hours aeration detention time.
In addition, the system will include RAS pumps, MLSS pump,
denitrified RAS recycle pumps, and appurtenances. The chemical

phosphorus removal system will consist of alum and polymer feed equipment,
chemical storage tanks, and appurtenances.
2. EXISTING ENVIRONMENT
A. General Description: The proposed expansion and phosphorus
removal facilities are to be constructed on the site of the existing South
Wastewater Treatment Plant (WWTP). The City -owned property encompasses
approximately 86 acres.
The WWTP site is southeast of Burlington on the west side of the Haw
River. It is about 3.5 miles south of Interstate 85. The attached
vicinity and location maps depict the WWTP site.
B. Topography: Topography of the site is typical Piedmont rolling
land. The site has slopes in the range of 2 percent to 6 percent. The
elevation at the site is 535 feet above MSL.
C. Soils: Soils at the site are Enon (fine sandy loam) and
Georgeville (clayey loam). Percolation for Enon soil is moderate to
severe and good to moderate for Georgeville soil.
The drainability for both type soils is generally good to
moderate.
D. Surface Water: The receiving water of the Haw River in the area
affecting the required effluent discharge from the WWTP has been declared
Nutrient Sensitive Water (NSW) by the State of North Carolina. The new
phosphorus limit of 2.0 mg/l will take effect beginning in January 1990.
3. NEED
The proposed phosphorus removal facilities are needed to meet the
2.0 mg/l phosphorus limitation.
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The need for the expansion from 9.5 MGD to 12 MGD is for the purpose
of prudent anticipation of the adequacy of the City's wastewater
facilities. As stated in Item 7. (SECONDARY ENVIRONMENTAL IMPACTS), the
population of the City has increased significantly over the past two (2)
decades, and it is expected that similar growth will occur over the next
two (2) decades.
4. ALTERNATIVE ANALYSIS
The alternatives which are casted below include the following
biological phosphorus removal processes, plus a chemical process and a no
action alternative.
A. Modified UCT Process:
Construction Cost
Concrete Work
$1,019,000
Reactor Tank(s), Mixers, Baffles, Handrails,
and Grating
402,000
Recycle Pump Station
147,000
Denitrification RAS Pump Station
80,000
Metering Pumps
16,000
Piping, Fittings, and Valves
816,000
Roadwork
20,000
Site Work and Excavation
71,000
Alum and Caustic Storage Tanks
107,000
Tank Heaters and Pipe Insulation
54,000
Electrical
267,000
$2,999,000
Contingencies (10%) 299,900
Engineering (10%) 299,900
Estimated Project Cost $3,598,800
Operation and Maintenance Cost
Electricity (170 HP at 90% of time) $ 59,800
Chemicals (Alum and Polymer) 45,200
Maintenance (Supplies and Replacement) 16,000
Labor (1 Operator at $20,000/Year) 20,000
Total Annual Cost $ 141,000
- 3 -

IF
Present Worth (20 Years - 8-7/8%)
$3,598,900 + $141,000 x 9.215 = $4,898,215
A?/0 Process:
Construction Cost
License Fee
$ 536,000
Concrete Work
973,000
Reactor Tank(s),
Mixers, Baffles, Handrails,
and Grating
403,000
Recycle Pump Station
147,000
Metering Pumps
16,000
Piping, Fittings,
and Valves
816,000
Roadwork
20,000
Site Work and Excavation
71,000
Alum and Caustic
Storage Tanks
107,000
Tank Heaters and
Pipe Insulation
54,000
Electrical
268,000
$3,411,000
Contingencies (10%) 341,100
Engineering (10%) 341,100
Estimated Project Cost $4,093,200
Operation and Maintenance Cost
Electricity (145 HP at 90% of time) $ 51,000
Chemicals (Alum and Polymer) 45,200
Maintenance (Supplies and Replacement) 16,000
Labor (1 Operator at $20,000/Year) 20,000
$ 132,200
Present Worth (20 Years - 8-7/8%)
$4,093,000 + $132,200 x 9.215 = $5,311,223
- 4 -

C. Modified Bardenpho Process:
Construction Cost
License Fee
Concrete Work
Reactor Tank(s), Mixers, Baffles, Handrails,
and Grating
Recycle Pump Station
Metering Pumps
Piping, Fittings, and Valves
Roadwork
Site Work and Excavation
Alum and Caustic Storage Tanks
Tank Heaters and Pipe Insulation -
Electrical
Contingencies (10%)
Engineering (10%)
Estimated Project Cost
Operation and Maintenance Cost
Electricity (145 HP at 90% of time)
Chemicals (Alum and Polymer)
Maintenance (Supplies and Replacement)
Labor (1 Operator at $20,000/Year)
$ 536,000
1,841,000
944,000
147,000
16,000
1,172,000
20,000
71,000
107,000
54,000
335.000
$5,243,000
524,300
524,300
$6,291,600
$ 51,000
45,200
16,000
20.000
$ 132,000
- Present Worth (20 Years - 8-7/8%)
$6,291,600 + $132,200 x 9.215 = $7,509,823
As noted, the Modified UCT Process (Alternative 1) is the least
present worth and is therefore the selected alternative.
MiE

D. Chemical Phosphorus Removal:
Construction Cost
Concrete Work $ 40,000
Alum and Caustic Storage Tanks 107,000
Tank Heaters and Pipe Insulation 54,000
Metering Pumps 16,000
Piping, Fittings, and Valves 38,000
Electrical 40,000
$ 295,000
Contingencies (10%) 29,500
Engineering (10%) 29,500
Estimated Project Cost $ 354,000
Operation and Maintenance Cost (Assume 10% Use)
Electricity (2 HP) $ 100
Chemicals 45,200
Maintenance (Supplies and Replacement). 2,000
Labor (1 Operator at $20,000/Year x 0.10) 2,000
Total Annual Cost $ 49,300
Present Worth (20 Years - 8-7/8%)
$354,000 + $49,300 x 9.215 = $ 808,300
NOTES:
1. There are no reasonable alternatives for this requirement.
2. The construction costs, as well as the operation and maintenance
costs, are included in each of the 3 alternatives evaluated, that is
the Modified UCT, A?L, and Modified Bardenpho.
3. As stated previously, the State's mandated new phosphorus limit of
2.0 mg/l will take effect beginning January 1990. The chemical
phosphorus removal facilities can be completed by November 1989.
However, the selected alternative (UCT Process) cannot be completed
until November 1991. Therefore, it is necessary to proceed with the
chemical portion of the selected alternative if Burlington is to meet
the State mandated deadline. The chemical system will serve as a
backup to the selected alternative.

E. No Action Plan: A no action alternative is not a viable option.
If the new phosphorus limit of 2.0 mg/l is not achieved by January 1990,
the City would be out of compliance with its NPDES permit.
5. ENVIRONMENTAL CONSEQUENCES
A. Beneficial Impact: The removal of phosphorus to the 2.0 mg/l
limit will have a beneficial impact on the environment. The removal of
biological nutrients will improve the water quality of the receiving
stream and will aid in the prevention of eutrophication.
B. Short Term Impacts: Basically, the negative impacts to the
environment will occur only during the construction phase of this project.
These potential impacts during construction include soil erosion, noise,
and dust.
6. MITIGATING MEASURES
The prevention of soil erosion can be obtained by strict adherence to
a State approved erosion control plan.
Since the existing wastewater treatment site is not near any densely
populated areas, noise should not be a problem. However, should noise be
a problem, it can be mitigated by limiting construction to normal working
hours.
Dust can be controlled by water spraying or other approved dust
control methods.
7. SECONDARY ENVIRONMENTAL IMPACTS
At the present time, the City of Burlington does not have any project
being planned which will utilize the proposed 2.5 MGD capacity expansion
of the South Burlington Wastewater Treatment Plant on the existing site.
It is therefore unwise, and, in fact, not possible at this time to define
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or describe any developable land area(s) or outfall corridor(s) where
there is any reasonable current expectation of development or utilization.
To attempt any evaluation or assessment of "secondary environmental
impacts" related to such locations at this time would be pure conjecture.
The City of Burlington has always been committed to the proper
protection of environment and will continue to do so for all planned and
definable projects where compliance with state and federal statutes is
required.
During the past two (2) decades, North Carolina has experienced
steady and significant growth in population. Except for a flat period of
adjustment and redirection in the early 70's, the City of Burlington has
witnessed a similar pattern of population growth. With its strong
heritage and tax base in industry and predominant textile influence, the
City is accustomed to prudent anticipation of the adequacy of its water
and wastewater facilities. The city electorate and City Council have
consistently supported an advocacy for capital investment in water and
wastewater facilities well ahead of actual needs.
Within the past year, the City of Burlington has received a
$2,400,000 EPA grant to perform modification/replacement for a failed I/A
technology at its South Burlington Wastewater Treatment Plant. An EPA low
interest loan of $3,600,000 has also been approved for phosphorus removal
at the South Burlington 'Wastewater Treatment Plant in compliance with
State of North Carolina requirements.
The magnitude of these mandated improvements at the South Plant is
sufficient to establish a significant "economy of scale" for the
construction project. This creates a window of opportunity for

accomplishing the modest 2.5 MGD capacity expansion at a very favorable
(reduced) cost, in anticipation of future residential and/or industrial
growth. It is therefore a prudent and cost effective decision for the
City of Burlington to fund the expansion in this project even though there
is no planned utilization for the additional treatment capacity at this
time.
B:S

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