City of Raleigh Corrective Action Plan (Neuse River Waste Water Treatment Plant) ENSR International

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February 8, 2005
S. Jay Zimmerman, L.G.
Aquifer Protection Section
NC Division of Water Quality
NC DENR Raleigh Regional Office
1628 Mail Service Center
Raleigh, NC 27699-1628
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Re: Corrective Action Plan (CAP) for Neuse River
Wastewater Treatment Plant Biosolids Application Fields
Dear Mr. Zimmerman:
Please find enclosed three (3) copies of the subject CAP that the City's consultants
(ENSR and others) has prepared regarding the issue of nitrate nitrogen levels in the
ground water at the biosolids application fields at the City's Neuse River Wastewater
Treatment Plant (NRWWTP). You requested the City prepare and submit the CAP by
January 31, 2005 in your Supplemental Site Assessment (SSA) comment letter dated
August 11, 2004.
The CAP represents a significant amount of work and time investment by City staff
and by the City's consultants in order to develop a plan to address the nitrate nitrogen
groundwater concern at some of the NRWWTP fields. We very much appreciate the
additional days that you provided us in order to finish preparation of the CAP.·
I would propose that once you have had an opportunity to review the CAP, that we
schedule a meeting to review the plan with you and other DENR staff, as we have
held after submitting the CSA and SSA for your review.
We look forward to meeting with you soon to discuss the CAP and to receiving final
approval by DWQ of the previously submitted Comprehensive Site Assessment
(CSA), the SSA and now the CAP.
If you have any immediate questions concerning this report or need additional copies,
please do not hesitate to contact me or Jack Moyer (857-4540), Tim Woody at the
NRWWTP (662-5700), Bill Doucette at ENSR (872-6600) or Steve Levitas (420-
1 707). Thank you.
Sincerely,
~
H. Dale Cris
Raleigh Public Utilities Director
Enclosure
cc: J. Russell Allen, City Manager
Jack Moyer, Deputy Public Utilities Director
Tim Woody, Reuse Superintendent
T.J. Lynch, Wastewater Treatment Plant Superintendent
Steven J. Levitas, Esq. -Kilpatrick Stockton
Bill Doucette -ENSR
CITY OF RALEIGH
Ne use River Waste Water Treatment Plant
Raleigh, North Carolina
Corrective Action Pla n
Prepared by:
IN TERNA TIONA L
ENSR Consulting and Engineering (NC), Inc.
7041 Old Wake Forest Road, Suite 103
Raleigh, North Carolina 27616
February 2005
CITY OF RALEIGH
Neuse River W aste W ater Treatment Plant
Raleigh, N orth Carolina
Prepared by:
INTERNATIONAL
ENSR Consulting and Engineering (NC), Inc.
7041 Old Wake Forest Road, Suite 103
Raleigh, North Carolina 27616
February 2005
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TABLE OF CONTENTS
1.0 INTRODUCTION ................................................................................................................................ 1-1
1.1 Report Organization .... .-............................................................................................................ 1-1
1.2 Site Background and History ................................................................................................... 1-2
1.2.1 Site Description ............................................................................................................. 1-2
1.2.2 Site History .................................................................................................................... 1-2
1.2.3 Site Physiography, Geology and Hydrogeology .......................................................... 1-2
1.3 ECS Investigation ..................................................................................................................... 1-4
1.4 Receptor Information ................................................................................................................ 1-5
1.5 CSA and SSA Investigations ................................................................................................... 1-5
1.5.1 Soil Analytical Results .................................................................................................. 1-6
1.5.2 Groundwater Analytical Results ................................................................................... 1-6
1.5.3 Surface Water Results .................................................................................................. 1-7
1.5.4 Soil PAN Evaluation ...................................................................................................... 1-7
1.5.5 Groundwater Flow and Fate and Transport Modeling ................................................ 1-7
1.6 Corrective Action Objectives .................................................................................................. 1-10
2.0 EVALUATION OF CORRECTIVE ACTION ALTERNATIVES ....................................................... 2-1
2.1 Technology Screening and Remediation Alternatives Evaluation ......................................... 2-1
2.1.1 Technology Screening for Groundwater ...................................................................... 2-1
2.2 Evaluation of Corrective Action Alternatives ........................................................................... 2-2
2.2.1 Groundwater Corrective Action Alternatives ................................................................ 2-2
2.3 Rationale for Selection of Groundwater Corrective Action Alternative ................................ 2-11
3.0 PROPOSED CORRECTIVE ACTION .............................................................................................. 3-1
3.1 Design Criteria .......................................................................................................................... 3-1
3.2 Groundwater Extraction System Implementation ................................................................... 3-2
3.2.1 Extraction Well and Monitoring Well Layout.. .............................................................. 3-2
3.2.2 Extraction Well and Monitoring Well Installation .......................................................... 3-2
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LIST OF TABLES
Table 1-1: Private Well Nitrate Nitrogen Results and Water Supply/Service Status
Table 1-2: Soil Analytical Results
Table 1-3: Groundwater Analytical Results -City Test Wells
Table 1-4: Groundwater Analytical Results-CSA-SSA Monitoring Wells
Table 1-5: Surface Water Analytical Results
Table 2-1: Screening of Groundwater Remediation Technologies and Process Options
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Table 2-2: Opinion of Probable Costs to Install and Operate a Groundwater Extraction System along
the Site Compliance Boundary with Discharge to the NRWWTP for treatment (Alternative 1) .
Table 2-3: Opinion of Probable Costs to Install and Operate a Groundwater Extraction System in .Field
#50, #500 and '1160 with Discharge to the NRWWTP or Land Application and Long-term
Monitoring in Other Areas (Alternative 2)
Table 2-4: Opinion of Probable Costs to Install and Operate a Groundwater Extraction System in Fields
#50, #500 and '1160 with On-site Treatment and Discharge, and Long-Term Monitoring in
Other Areas (Alternative 3)
Table 2-5: Opinion of Probable Costs for Enhanced Denitrifcation (EON) in Fields #50, #500 and #60
and Long-term Monitoring in Other Areas {Alternative 4)
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..
Figure 1-1:
Figure 1-2:
Figure 1-3:
Figure 2-1:
Figure2-2:
Figure 2-3:
Figure 2-4:
Vicinity Map
Site Map
Nitrate Analytical Data
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LIST OF FIGURES
Conceptual Layout of Extraction Wells along Compliance Boundary, with Discharge to
NRWWTP (Alternative 1)
Conceptual Layout of Extraction Wells in Field #50, #500 and #60, with Discharge to
NRWWTP or Land Application and Long-term Monitoring (Alternative 2)
Conceptual Layout of Extraction Wells in Field #50, #500 and #60, with On-site
Treatment and Discharge, and Long-term Monitoring (Alternative 3)
Conceptual Layout of Enhanced Denitrification System in Field #50, #500 and #60 and
Long-term Monitoring (Alternative 4)
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1.0 INTRODUCTION
ENSR Consulting and Engineering (NC), Inc. (ENSR) prepared this Corrective Action Plan (CAP)
Report on behalf of the City of Raleigh Public Utilities Department (CORPUD) to address nitrate
contamination in groundwater at the biosolids application fields serving the Neuse River Waste Water
Treatment Plant (NRWWTP). The NRWWTP (the Site) is located at 8500 Battle Bridge Road in
Raleigh, Wake County, North Carolina. The location of the Site is shown in Figure 1-1. The CAP has
been prepared at the request of Raleigh Regional Office (RRO) of the North Carolina Department of
Environment and Natural Resources (NCDENR) Division of Water Quality (DWQ), Aquifer Protection
Section (APS). The CAP was requested by the RRO in a letter to the CORPUD, dated August 11,
2004.
ENSR completed a Comprehensive Site Assessment (CSA) on behalf of the CORPUD and submitted
a CSA Report to NCDENR in December 2002. In January 2003, the NCDENR requested further
assessment to meet the requirements of Title 15A North Carolina Administrative Code (NCAC)
Subchapter 2L Section .0106(d) relating to the conditions at the NRWWTP. A Supplemental Site
Assessment (SSA) was completed and the report was submitted in September 2003 (ENSR, 2003).
Data collected during the CSA and SSA was used to evaluate groundwater flow patterns, nitrate
concentrations in groundwater and soil nitrogen profiles at the Site. Results obtained during the CSA
and SSA are summarized in Section 2.0.
Following review of the SSA Report, . the NCDENR requested preparation of a CAP to address
groundwater contamination and mitigate the hazards posed by the contamination in areas where it has
spread beyond the Site's compliance boundary. The CAP was prepared in accordance with Title 15A
NCAC Subchapter 2L Section .0106(d)(2). The primary objective of this CAP is to evaluate soil and
groundwater corrective action alternatives and propose an appropriate remedy for the Site.
1.1 Report Organization
The CAP Report is organized as follows:
• Section 1:
• Section 2:
• Section 3:
• Section 4:
Introduction and Site Investigation Summary
Evaluation of Corrective Action Alternatives
Proposed Corrective Action
References
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1.2 Site Background and History
1.2.1 Site Description
The NRWWTP consists of approximately 1,030 acres of mostly contiguous farmland owned or leased
by CORPUD and divided into numbered fields. Properties surrounding the Site consist of residential
properties, farmland, and state owned forestland . The northern and eastern Site boundaries border a
3.6-mile section of the Neuse River. Beddingfield Creek bounds the Site to the south. Topographically,
the Site ranges in elevation from an approximate high of 270 feet above mean sea level (ft msl) in
upland areas to an approximate low of 140 ft msl at the Neuse River (ENSR, 2002). A layout of the
facility, associated biosolids application fields and the current compliance boundary are depicted on
Figure 1-2.
The Neuse River is classified as a Class C NSW (nutrient sensitive water) from the Falls Lake Dam to
the mouth of Beddingfield Creek. From the mouth of Beddingfield Creek to approximately 0.2 miles
downstream of Johnson County State Road 1700, the Neuse River is classified as Water Supply V
Nutrient Sensitive Water (NSW). Beddingfield Creek is classified as C NSW from the source to the
Neuse River. No nitrate water quality standard has been established for class C NSW surface water.
For surface waters classified as Water Supply V NSW, nitrate water quality standard is 10 milligrams
per liter (mg/L).
1.2.2 Site History
The wastewater treatment plant (WWTP) has been operated since 1976 and has land-applied
biosolids since 1980 under a land application permit (Permit# WQ0001730). During this period, fields
have been added and removed from biosolids application. Fields 1, 2 and 3 were removed from
biosolids application in 1998 and converted into a police training facility. Fields 100, 101, 102, 200,
201, 500, 512, 513, 522, 523 and 524 were formerly leased for biosolids application. Currently leased
fields include 600, 601, 602 and 603. The remaining fields are owned by CORPUD. The permit allows
for application of 7,000 total dry tons of Class B Biosolids per year on fields listed in the permit.
Groundwater quality monitoring required under the permit revealed exceedances of NCAC Subchapter
2L nitrate groundwater standard in proximity to the compliance boundary of CORPUD owned biosolids
application fields. According to CORPUD personnel, land application of biosolids was suspended in
September 2002 (ENSR, 2003).
The property containing former leased Fields 100, 101,102,522,523, and 524 is currently owned by
Material Recovery, LLC (Material Recovery). This property has been developed as a construction and
demolition (C&D) landfill.
1.2.3 Site Physiography, Geology and Hydrogeology
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Regional Physiography
The Site is situated within the eastern Piedmont Physiographic Province of North Carolina. Area
topography consists of rolling hills dissected by narrow v-shaped drainage ways and perennial streams
that drain into Neuse River. Localized steep bluffs exist to the south along Beddingfield Creek and
along the Neuse River to the east and north of the Site (May and Thomas, 1965). Localized bluffs in
this area plateau to narrow bench cut alluvial floodplains that are nearly flat with incised drainage ways
to the Neuse River.
Site Geolo gy
The Site is within the Raleigh Geologic Belt and the underlying bedrock consists of massive granitic
rock of the Rolesville series. The granitic bedrock is part of an intrusive series described as
megacrystic to equigranular and is dated between 270 and 320 million years old (Pennsylvanian to
Permian). Mafic dikes have been identified regionally and generally have a northwest to southeast
alignment. According to published literature, these dike features may be up to 100 to 200 ft wide.
Smaller dikes plays may be 10 to 20 ft wide (Parker, 1979). Details of the dikes and geologic maps
can be found in the SSA (ENSR, 2003).
Lithologic units identified at the Site are typical of the piedmont and include the following:
• Topsoil and weathered parent rock material, referred to as saprolite tends to be moderately
thick in locations without visible rock outcropping. Site saprolite consists of yellow brown to
orange sandy silts (ML) to silty sands (SM) with the coarser material at depth. Regionally,
saprolite can vary in thickness from a few feet to up to hundreds of feet. Saprolite typically
contains relict structures and fabric from the parent rock from which it has weathered.
Saprolite thickness at the Site commonly ranges between 30 and 60 feet below surface grade
(bsg).
• Partially weathered rock (PWR), often referred to as the transition zone between saprolite and
the parent unweathered bedrock, often exhibits the same properties as deeper saprolitic soils
(SM) but with higher occurrence of rock and rock fragments. PWR thickness often ranges from
0 to 10 ft thick on ridges and uplands to 10 to 20 ft thick along slopes and low-lying areas
(Wilson and Carpenter, 1981 ).
• Bedrock in this area typically consists of granitic rock with fractures near the interface of PWR
and bedrock. The number and size of the fractures generally dissipate with depth while voids
and vugs are common in shallow rock zones when weak exfoliation soil zones are
encountered near PWR.
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Hydrogeology
Hydrogeologically, the Site is situated in a meta-igneous hydrostratigraphic unit of the eastern
Piedmont of North Carolina (Daniel and Payne, 1990). Two general hydrostratigraphic units (saprolite
and PWR/upper bedrock) characterize the regional hydrogeology. The upper saprolite unit is an
unconfined storage aquifer that transmits water downward to the lower semi-confined PWR and
fractured confined crystalline bedrock aquifer unit. Groundwater yields often range from 2 to 20 gallons
per minute (gpm) within the unit (Daniel and Payne, 1990). Groundwater occurs where saprolite and
localized sedimentary/alluvial deposits along the Neuse River overlie bedrock. Groundwater
movement in the saprolite is controlled by groundwater divides associated with ridges and streams.
The typical flow of groundwater occurs from upland areas (ridgelines) to perennial streams. The
underlying granitic rocks are known to have lower hydraulic conductivities than either saprolite or PWR
and controls deep groundwater or regional groundwater flow conditions. The PWR lies between
saprolite and bedrock units and groundwater movement flows both within the material matrix and
through fractures. Groundwater movement in bedrock is restricted to intersecting sets of water-bearing
fractures and joints (Harned and Daniel, 1989).
Hydraulic properties of the saprolite and PWR zones were evaluated using rising and falling head slug
test methods. Hydraulic conductivity (K) values for the shallow aquifer ranged from 1.3 x 10-6 to
6.4 x 10-3 centimeters per second (cm/sec). K values for PWR wells ranged from 4.4 x 10-5 to
1.1 x 10-3 cm/sec. A transmissivity of 4.6 x 10-5 square centimeters per day (cm 2/day) (1.3 square feet
per day [ft2/day]) was obtained for well MW-126d (ENSR, 2003).
1.3 ECS Investigation
In April 2002, Engineering Consulting Services, Ltd. (ECS) was contracted by CORPUD to investigate
the occurrence of nitrate in groundwater at the Site. The findings of the ECS investigation are
summarized in the Report of Investigations (ECS, 2002a). The investigation focused on seven
biosolids land application areas (including Fields 4, 5, 11, 12, 17-22, 47, 48, 74, 75, 519, and 520).
Results of the soil analysis indicated that in general, ammonia, total organic carbon {TOC) and total
Kjeldahl nitrogen (TKN) concentrations decreased with depth, while nitrate concentrations increased
with depth to the maximum sampling depth of 6.0 ft. In general, groundwater samples collected from
the investigation areas indicated nitrates exceeding the 2L groundwater standard at locations where
nitrate concentrations in soil increased in depth. ECS concluded that not all of the nitrogen being
applied to the Site is assimilated by cover crop in the year of application and that a portion of the
unused nitrogen accumulates in the soil with each application to become plant available in subsequent
years. ECS concluded that plant available nitrogen (PAN) applications during the period from 1996 to
2000 exceeded the maximum annual permit limit of 250 pounds PAN/acre/year (lbs PAN/acre/yr) in
the older fields. The report noted that PAN applied in excess of crop needs is mobilized below the root
zone and migrates to the water table (ECS, 2002a).
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1.4 Receptor Information
The key receptors of groundwater migrating from the Site are the Neuse River and its tributaries.
Water supply wells at nearby residences determined to be potential receptors in the CSA and SSA
have been replaced with public water supply and the former water supply wells have been abandoned.
In 2002, CORPUD sampled thirty-six private water supply wells located in the vicinity of the Site.
Analytical data indicated that seven wells had nitrate concentrations in excess of 10 mg/L (refer to
Table 1-1). CORPUD subsequently initiated a quarterly sampling program of private water supply wells
located within ½ mile of the biosolids application field boundaries. Forty-five private and/or community
water supply wells were identified and included in the sampling program. A summary of the wells
identified within proximity of the Site and associated analytical results (from CORPUD sampling
program) are listed in Table 1-1. The locations of the water supply wells are depicted on Figure 1-3.
Thirty-nine of the forty-five properties included in the sampling program were subsequently connected
to the public water supply system. These thirty-nine properties were served by thirty-eight water supply
wells, of which thirty-seven wells have been decommissioned consistent with the NCAC Subchapter
2L requirements. Per the information provided by CORPUD, the residential property with the remaining
private water supply well has been connected to the public water supply system; however, the well will
not be abandoned as requested by the property owner.
Based on the information provided by CORPUD, currently there are six private water supply wells
(identified as PW-24, PW-25, PW-27, PW-38, PW-42, and PW-43 in Table 1-1) that are still in use
(active) and remain in the CORPUD sampling program. It should be noted that CORPUD is in the
process of purchasing two properties owned by Ms. Lucy Moore. These properties include water wells
PW-27 and PW-28. Once they purchase these properties, these water wells will be abandoned. The
other water supply wells listed in Table 1-1 have been abandoned. Nitrate concentrations for the six
currently active water supply wells were below 10 mg/L during the four 2004 sampling events (refer to
Table 1-1). These si>< wells are not likely receptors for nitrate impacted groundwater migrating from the
biosolids application fields. CORPUD will continue to monitor the six remaining wells as long as
required under the land application permit.
1.5 CSA and SSA Investigations
A CSA was conducted between October and December 2002. Additional assessment was conducted
following the CSA work and was summarized in the SSA Report. The focus of CSA and SSA was to
provide data necessary for evaluating groundwater flow patterns, compliance boundary nitrate
concentrations in groundwater and soil nitrogen profiles at the Site.
Soil and vadose zone characterization focused on determining if soil nitrate profiles observed
previously by ECS in the vicinity of known problem fields were also reflected in other application fields
that have not been part of the biosolids application program for some time. The groundwater
assessment included installation and sampling of twenty-two shallow temporary monitoring wells,
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twenty-three shallow permanent monitoring wells constructed in saprolite zone, four wells in partially
weathered rock (PWR) zone, four permanent wells in the bedrock. In addition, two private water supply
wells (i.e., PW-8 and PW-39) were also sampled during the groundwater assessment. Surface water
samples were collected along Beddingfield Creek, an unnamed tributary to the Neuse River along the
western boundary of the Site, and springs and seeps within the application boundaries to assess
surface water quality. In addition, three monitoring wells (i.e., MW-1, MW-3, and MW-5) installed by
Material Recovery for compliance monitoring of the C&D landfill were also sampled. The groundwater
monitoring wells, CORPUD sampled test wells, and soil and surface water sampling locations are
depicted in Figure 1-3. In addition, as part of SSA, an incubation study was conducted to estimate the
amount of residual PAN in topsoil for the 2003 growing season. A brief summary of CSA and SSA
results is provided in the following sections.
1.5.1 Soil Analytical Results
Results of the soil samples collected from Fields 3, 100, and 500 are summarized on Table 1-2. Soil
sample locations are also illustrated on Figure 5 of the CSA. The data indicate concentrations of nitrate
generally peak in 4 to 8 ft depth interval, referred to as 'bulge' (ENSR, 2002). The soil profile nitrate
concentrations are expected to change over time, but the bulge is likely to stay in approximately same
depth interval. The implication of this feature is that nitrates are accumulating at the bulge through
mechanisms such as infiltration redistribution (some water takes a rather slow pathway through the
soil) and anion exchange (nitrate is an anion).
The maximum soil nitrate concentrations in Field 100 were 3 to 4 times above the maximum
concentration found in Fields 3 and 500. The soil results indicated that after a fallow period of 2 to 4
years the TKN in the top layer apparently had not decreased to pre-application levels as reported by
ECS (ENSR, 2002). The implication is that the top soil residual organic nitrogen will likely continue as a
source of PAN for a longer period in both active and inactive application fields. However, the subsoil
data from the inactive Fields 3 and 500 suggested that four to eight years after ceasing biosolids
application, significant reductions in soil nitrate concentrations could occur. Nitrates accumulated in the
subsoil, while retarded to some extent will likely continue to migrate to groundwater for several years
(ENSR, 2002).
1.5.2 Groundwater Analytical Results
Groundwater analytical data for the CORPUD test wells and the CSA-SSA wells is provided in Tables
1-3 and 1-4, respectively. The groundwater analytical data is depicted in Figure 1-3. The data indicated
that nitrate exceeded its 2L groundwater standard at locations near the compliance boundary in the
areas of Fields 6, 12, 18, 19, 41, 47, 50, 60, 61, 62 63, 74,100,201,500, and 503. The deep saprolite
well (MW-113d) and bedrock wells (MW-101d, MW 105d and MW-111d) also exceeded nitrate
groundwater standard (ENSR, 2002).
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Analytical results suggest a potential for nitrates from biosolids application in Field 50 to have impacted
groundwater on the residential property to the east and in the former private water supply well
(PW-22). Field 50 received biosolids routinely between 1982 and 2002 and has been reported to have
received excess PAN applications in 8 of those years (ENSR, 2002). Results from assessment of Field
500 suggested a more limited potential for nitrate impacts from biosolids application.
Off-site nitrate impacts to groundwater associated with biosolids application in the vicinity of the
intersection of Old Baucom Road and Mial Plantation Road does not appear to extend significantly
east of Shotwell Road or Mial Plantation Road. Nitrates in groundwater exceeded the nitrate
groundwater standard within Field 500 in the vicinity of former private water supply wells PW-8,
PW-12, PW-30, and PW-36. The application history for Field 500 indicates that biosolids application to
Field 500 ceased in 1994 and that biosolids application rates were generally less than other application
fields such as Field 50. Field 500 apparently has been cropped several years before and after biosolids
application. The SSA concluded that detected nitrates in groundwater in Field 500 were not due to
biosolids application alone (ENSR, 2003).
Analytical data from wells located across major streams such as Beddingfield Creek indicated that
migration of nitrate impacted groundwater under the stream is likely not occurring (ENSR, 2003).
1.5.3 Surface Water Results
Surface water analytical results are tabulated in Table 1-5 and depicted on Figure 1-3. The surface
water data from several samples collected in first order tributaries and seeps within the application
areas had nitrate concentrations above 1 O mg/L. Nitrate in surface water suggests groundwater
discharges to the streams and tributaries (ENSR, 2002). Nitrate in samples collected from Beddingfield
Creek and the Neuse River were lower and did not exceed 10 mg/L.
1.5.4 Soil PAN Evaluation
An incubation study was conducted as part of SSA to estimate the amount of PAN in soils from fields
at the NRWWTP and the residual PAN for the 2003-growing season. The details of PAN evaluation
were included in the SSA Report (ENSR, 2003). The soil PAN evaluation indicated that many of the
fields in the study area could supply adequate to excessive amounts of PAN for crop production. The
evaluation indicated that approximately 38 fields would supply PAN in excess of the amount required
for anticipated crop production in 2003 (ENSR, 2003).
1.5.5 Groundwater Flow and Fate and Transport Modeling
Groundwater flow and transport models were constructed to assess the distribution of nitrate in
groundwater and the discharge of nitrogen from groundwater to the Neuse River. Design criteria,
inputs, and results for the models are summarized in SSA Report (ENSR, 2003). The models were
constructed using the following four layers: Layer 1 -saprolite unit; Layer 2 -PWR unit;
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Layer 3 -upper fractured bedrock zone; and Layer 4 -lower unfractured bedrock zone. Key
conclusions derived from the construction, testing and application of the nitrate transport model are
listed below:
• Steady-state groundwater flow patterns and the historical location and rates of biosolids
application to CORPUD fields determine the distribution and magnitude · of nitrate in
groundwater .in the vicinity of the fields.
• The methodology used to estimate nitrate concentrations in recharge that were used as input
to Groundwater Transport Model uses available and pertinent records of PAN for the
NRWWTP fields, includes the use of a mineralization rate for organic nitrogen of 30%, and
accounts for the build up of carryover PAN not removed by crop harvest and volatilization.
• The groundwater flow and transport models are consistent with the available data. The flow
model recreates the observed distribution of groundwater head. Importantly, the transport
model generally captures the nitrate concentration as well as its pattern of temporal change.
This supports the ability of the model to represent the factors driving the transport of nitrate at
the Site.
• The transport model simulates historical concentrations in monitoring wells that are generally
greater than observed values, particularly for observed values that are greater than 10 mg/L.
As a result the simulated extent of nitrates in groundwater and associated loading to surface
water are likely overestimated.
• The approximate nitrogen concentration in the Neuse River as a result of the simulated peak
groundwater to surface water loading from biosolids application computed using an average
annual flow of 1,053 cubic feet per second (ft3/sec) is 0.12 mg/L. The peak concentration is
predicted to occur in 2006. Because this concentration is so low and because of nitrogen
discharge to the Neuse River from the NRWWTP, from upstream and non-CORPUD sources,
the impact of nitrogen discharge to the Neuse River via groundwater discharge cannot reliably
be monitored by sampling in the Neuse River.
• The simulated 1 O mg/L nitrate iso-concentration line at the end of 2002 in the southeast portion
of the CORPUD Site, in the vicinity of Fields 200, 201, and 500 (along Shotwell Road) extends
approximately 500 ft south and east the boundaries of CORPUD Fields . The principal direction
of migration in this area is south and east towards Beddingfield Creek.
• Nitrate concentrations in groundwater and private water supply wells in the area along Old
Baucom Road and along Shotwell Road are likely the result of a combination of pre-CORPUD
and non-CORPUD agricultural operations on upgradient fields .
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• Nitrates in private wells east of Mial Plantation and Shotwell Road in the vicinity of the
intersection with Old Baucom Road are the result of additional sources of nitrate such as
leaking septic systems. It is unlikely that private wells north of Fields 60 to 63 have been
impacted by nitrates from CORPUD fields because they are hydraulically upgradient.
• Assuming a maximum nitrate concentration in groundwater of 6 mg/L for CORPUD and
non-CORPUD agricultural fields from 2003 to 2053, simulated concentrations in model layers 1
and 2 are reduced to less than 10 mg/L in the offsite area between Field 600 and Shotwell
road in approximately 1'5 years. In approximately 23 years, under this condition, nitrate
concentrations beneath Field 500 are predicted to be less than 10 mg/L.
• Simulations from 2003 to 2053 show that levels of nitrates less than 10 mg/L are not likely to
be achieved after 30 to 40 years in areas between CORPUD fields and the Neuse River,
Beddingfield Creek and the tributary that drains the northwest portion of the CORPUD fields,
even if biosolids are managed such that that the maximum leached nitrate concentration in
recharge is less than 6 mg/L or less.
• Intrusive diabase dikes have been mapped at the Site and in its vicinity. Evidence of the dikes
was independently obtained as part of the SSA investigation. The hydraulic impact of the
dikes is not fully understood. However, the groundwater flow model was modified to provide a
representation of the dikes that would have the greatest potential impact on groundwater flow
as follows: each dike was simulated as a low conductivity vertical barrier with zones of
relatively high conductivity on either side to simulate country rock fracturing by intrusion of the
dike material. Each dike is assumed to fully penetrate all model layers. The net effect of this
representation is that groundwater flow and nitrate transport, will be impeded across the dike
but will be accelerated along the edges of the dike. Despite this representation, simulated
nitrate transport is not greatly affected at the Site and its environs. There are several locations
where the nitrate plume is changed slightly in the vicinity of a simulated dike but the
conclusions described above (i.e., nitrate transport is limited to migration to surface waters
located in valleys and that many private wells are not greatly affected by CORPUD activities)
are unchanged by the presence of the dikes.
The following are the key conclusions and recommendations provided in the CSA and SSA reports:
• Groundwater impacted with nitrates from biosolids application is likely contained within the
area bordered by the major streams and Neuse River. The potential for nitrate impacted
groundwater to migrate into areas of human water supply use of groundwater was limited to
the eastern boundary of the Site in the general vicinity of the intersection of Mial Plantation,
Shotwell, and Old Baucom Roads.
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• Surficial soil (topsoil) with elevated organic nitrogen was likely to continue to release PAN as
part of normal biodegradation processes and unless the crop utilized the nitrogen, would most
likely continue to impact groundwater quality.
• Subsurface soil data suggested that the accumulation of nitrates that occurred during past
biosolids application was temporary. Within four to eight years, a significant reduction in soil
nitrate concentrations appeared possible.
• The extent of nitrate contamination of water supply wells was limited to the vicinity of Old
Baucom Road and Mial Plantation Road south of the Neuse River. The source of nitrates
detected in these wells was likely a combination of septic systems, fertilization of upgradient
fields and biosolids application to upgradient fields and the properties containing the water
supply wells, and biosolids application.
A recommendation was made that CORPUD revise its biosolids management program to include soil
sampling for residual top soil PAN, routine PAN measurements in biosolids and creation of a decision
model incorporating such measurements to better match biosolids application to expected crop
nitrogen uptake.
1.6 Corrective Action Objectives
The combined CSA and SSA demonstrate that Site hydrogeologic conditions will contain the biosolids
nitrate-impacted groundwater within a relatively short distance of the application fields. The extent of
biosolids nitrate-impacted groundwater is not likely to increase laterally or vertically. Surface water
impacts have been conservatively quantified and risks to human health from nitrate impacted
groundwater have been mitigated. The transport model predicts that nitrate concentrations in
groundwater and surface water will decline over time since excess biosolids application has ceased
(ENSR, 2003).
The media of concern at the Site are soil and groundwater impacted with nitrate. The corrective action
objectives for the Site are to:
• Implement measures to minimize leaching of residual soil nitrogen in the biosolids application
fields;
• Implement measures that address areas where an exceedance of nitrate groundwater
standard has occurred at or beyond the Site's compliance boundary and where the current use
of the downgradient property is residential; and,
• Monitor nitrate levels in other areas where an exceedance of nitrate groundwater standard has
occurred at or beyond the Site's compliance boundary.
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Based on available data and groundwater flow and transport modeling, exceedances of nitrate
groundwater standard have occurred at or beyond the compliance boundary for Fields 50, 500 and 60
and there are existing residential properties immediately downgradient of these fields (although the
residential properties have been connected to the public water supply system). As noted above, active
remediation measures are being proposed in these locations. With respect to the remaining areas of
the Site where exceedances of nitrate groundwater standard have occurred at or beyond the
compliance boundary, there are no downgradient residential properties between the fields and a
surface water hydraulic boundary. Long-term monitoring only is proposed for those areas and
CORPUD proposes to seek a variance from the Environmental Management Commission to allow for
such monitoring in lieu of active remediation.
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2.0 EVALUATION OF CORRECTIVE ACTION ALTERNATIVES
This section of the CAP identifies and screens potentially applicable technologies and evaluates
alternatives for containing/treating nitrate impacted groundwater within the Site's compliance boundary.
The CSA/SSA documented the presence of residual organic nitrogen in the topsoil of select application
fields at levels likely to result in the release of PAN as nitrate greater than crop needs. Specifically the
2003 incubation study performed under the direction of Dr. Larry King indicated an organic nitrogen
mineralization rate of up to approximately 5 to 7 percent in approximately 17 weeks (ENSR, 2003). In
38 fields, PAN from residual organic nitrogen mineralization was estimated to exceed 200 lbs/acre
during the 2003 growing season. CORPUD is completing development of a biosolids land application
operations plan, as required under the new land application permit, which will encompass protocols for .
routine evaluation of PAN from residual organic nitrogen mineralization and a cropping system to
enhance the uptake of residual soil PAN.
2.1 Technology Screening and Remediation Alternatives Evaluation
Technologies potentially applicable for addressing nitrated impacted groundwater and those that would
assist in meeting corrective action objectives were reviewed. A preliminary screening was performed to
identify applicable technologies for groundwater. The preliminary screening criteria used in this
evaluation are technology effectiveness, implementability and relative costs.
2.1.1 Technology Screening for Groundwater
This section describes the initial steps in development of corrective action alternatives for addressing
nitrate impacted groundwater. Based on the preliminary screening process, technologies retained were
assembled into potential corrective action alternatives. Since groundwater contamination is limited to
nitrate, the technology screening process was limited to technologies that can address nitrate
contaminated groundwater. Table 2-1 presents a summary of screening of potential groundwater
technologies. Based on the screening, the following technologies were retained for formulation of
corrective action alternatives.
• Groundwater extraction
• Ion exchange
• Filtration
• Natural attenuation processes
• Denitrification (abovegrade)
• In-situ denitrification (biological reduction)
• Institutional controls such as alternative water supply and use restrictions
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• Discharge to stream (surface water)
• Land application/spray irrigation
• Discharge to POTW
These technologies were used to develop potential corrective action alternatives to address nitrate
contaminated groundwater at the Site . In addition, consideration was given to a monitoring only
variance request from the NCAC Subchapter 2L for portions of the Site where environmental and
human health risks were very low.
2.2 Evaluation of Corrective Action Alternatives
This section of the CAP evaluates potential corrective action alternatives for remediating the impacted
groundwater using the following two criteria:
• Feasibility and,
• Limitations.
Based on these criteria, four potential groundwater corrective action alternatives were assembled for
further evaluation. These alternatives are briefly discussed below along with a rationale for selecting
the suitable alternative to meet the corrective action objectives. Because the conceptual processes
described for each corrective action alternative are not based on final engineering designs, the
probable costs presented for each alternative are intended only as comparative estimates in this
evaluation process.
2.2.1 Groundwater Corrective Action Alternatives
2.2.1.1
System Process Descri ption
Alternative 1: Groundwater Extraction along the Compliance
Boundary and Discharge to NRWWTP
This alternative would involve collection of groundwater contaminated with nitrates at locations where
the nitrate groundwater standard is exceeded arid/or estimated to be exceeded based on groundwater
modeling at the compliance boundary (along the perimeter of the Site). Recovery wells would be
installed at various locations and depths to allow extraction of groundwater impacted with nitrate and
contain the plume from migrating either into off-site properties or into Neuse River or its tributaries.
Extracted groundwater would be pumped through a network of extraction piping to the NRWWTP
where it would be treated and discharged. This alternative assumes that a small volume of residual
nitrate in portions of the plume that have migrated beyond the Site's compliance boundary and which
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may not be captured by the recovery wells would be discharged into the Neuse River and its
tributaries.
Based on hydrogeologic data and results of groundwater flow modeling, it is anticipated that
approximately 426 extraction wells (100-ft spacing) would be installed along the portions of the
compliance boundary where nitrate groundwater standard has exceeded and/or is estimated to be
exceeded based on groundwater modeling. Figure 2-1 depicts a conceptual layout of the extraction
wells. The depth of extraction wells would most likely vary in different areas of the Site based on
elevation and water table; however, the probable cost for this alternative is based on an average depth
of 70 ft bsg. For the purpose of this evaluation, · an average groundwater yield from each well is
assumed to be 2 gpm (1,226,880 gallons per day). Based on locations of the current monitoring wells
(installed by ENSR) and test wells (monitored by CORPUD), it is anticipated that four additional
monitoring wells would be installed as part of the monitoring program. The piping required to convey
water to the NRWWTP is assumed to be installed underground (i.e., in trenches) along the roads and
fields;
To monitor effectiveness of this corrective action alternative, it is assumed that approximately 12
monitoring wells and 10 surface water locations would be sampled three times per year and analyzed
for nitrate for the life of the project. In addition, 88 recovery wells are assumed to be sampled annually
for nitrates. It should be noted that currently, the CORPUD samples the test wells three times a year as
part of the compliance monitoring for the Site. Analytical data from these test wells would be used to
evaluate the effectiveness of this alternative. For the purpose of costing and comparison, it is assumed
that the project life of this alternative is 30 years.
Feasibility
This full containment alternative has the potential to be effective at preventing the majority of the
groundwater with nitrate concentrations exceeding 10 mg/L from migrating beyond the Site's
compliance boundary. Groundwater extraction is a proven technology for plume containment. As long
as the extraction system is operational, this alternative can effectively contain the nitrate impacted
groundwater from migrating beyond the Site's compliance boundary at concentrations exceeding 10
mg/L. Treatment of water at the NRWWTP is expected to be effective in reducing nitrate
concentrations to below discharge requirements.
The extraction wells for this alternative can be installed utilizing standard drilling techniques. No special
equipment or specialists other than a driller and a construction contractor are anticipated during
implementation. The periodic groundwater sampling associated with the groundwater extraction
system can be easily implemented.
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Limitations
This alternative would require significant long-term maintenance of the extraction system. The
extracted water would be approximately 1,226,880 gallons per day (based on 426 recovery wells and
flow rate of 2 gpm per well) and will have to be treated at the NRWWTP. Use of currently available
capacity would reduce the plant's capability to accommodate projected growth. Therefore, the
NRWWTP may have to be expanded beyond what is currently planned (incurring additional
construction costs) to handle the additional hydraulic and nitrate loading from the recovery wells. Due
to significant length of trenching and piping and number of extraction wells required, this option would
be very expensive. Large scale groundwater extraction along streams can deplete significant stream
base flow which could subsequently result in disrupting stream aquatic habitats.
Probable Costs
The present worth of opinion of probable costs for this alternative is approximately $25,246,300. The
present worth value was calculated using a discount rate of 5.125 percent. Details of the opinion of
probable costs and key assumptions are included in Table 2-2. These costs include costs for capital
and operational tasks . It should be noted that costs to monitor compliance wells (test wells) required
under the biosolids permit are not included in this estimate. In addition, these probable costs are for
evaluation of alternatives and actual costs of implementation may . vary (typically around -30 to +50
percent).
2.2.1.2
S ystem Process Descri ption
Alternative 2: Groundwater Containment in Field 50, 500 and 60,
Discharge to NRWWTP or Land Application, and Long-Term
Monitoring in Other Areas
Based on the available information, and groundwater flow and transport modeling, exceedances of the
nitrate groundwater standard have occurred at or beyond the compliance boundary for Fields 50, 500,
and 60 and there are existing residential properties immediately downgradient of those fields (although
the properties have been connected to the public water supply system and the wells have been
abandoned). This alternative is intended to control further off-site migration of nitrate impacted
groundwater in the above-mentioned fields only. With respect to the remaining areas of the Site where
exceedances of nitrate groundwater standard have occurred at or beyond the compliance boundary,
there are no downgradient residential properties between the field boundaries and a surface water
hydraulic boundary. Under this alternative, long-term monitoring only is proposed for those areas and
CORPUD proposes to seek a variance from the Environmental Management Commission to allow for
such monitoring in tieu of active remediation.
This alternative involves collection of nitrate impacted groundwater using appropriately spaced
extraction wells in Fields 50, 500 and 60. The groundwater extraction (recovery) wells would be
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installed within the compliance boundaries in the three fields listed above to allow containment of the
dissolved nitrate plume exceeding nitrate groundwater standard. These extraction wells are expected
to be installed to depths ranging from 60 to 80 ft (in partially weathered rock/fractured bedrock).
Based on hydrogeologic data and results of the groundwater capture zone modeling (see Appendix A),
it is anticipated that approximately 7 extraction wells will be installed near the eastern compliance
boundary of Field 50 to a depth of approximately 80 ft bis. In addition, approximately 22 extraction
wells would be installed near the eastern compliance boundary of Field 500, and 11 extraction wells
will be installed near the southern compliance boundary of Field 60. The depth of extraction wells in
Fields 500 and 60 is approximately 60 ft bsg. Figure 2-2 presents a conceptual layout of the proposed
extraction wells. For the purpose of this evaluation, yield from each well is assumed to be
approximately 2 gpm.
Approximately 115,200 gallons per day of extracted groundwater will be pumped to the NRWWTP for
treatment or application to selected fields as irrigation. In the long-term, CORPUD intends to irrigate all
of the application fields as a best management practice to optimize crop growth/yields and nitrogen
uptake. CORPUD is currently permitted to irrigate reclaimed wastewater to approximately 105 acres of
biosolids application fields. CORPUD will soon request a permit modification to add 140 more acres to
the irrigation program. Under this alternative, CORPUD will have the option to irrigate the extracted
nitrate impacted groundwater provided an appropriate land application permit modification is approved.
The extracted groundwater will be stored in existing digesters that are discontinued for wastewater
treatment (6,500,000 gallons capacity) prior to irrigation or treatment. A conservative estimate is that
the currently permitted 105 acres will be more than sufficient to absorb the extracted groundwater flow.
As discussed earlier, under this alternative, long-term monitoring only is proposed for the remaining
areas of the Site, where exceedances of the nitrate groundwater standard have occurred at or beyond
the Site's compliance boundary. Based on locations of the current monitoring wells and test wells at
the Site, it is anticipated that four additional monitoring wells would be installed as part of the
monitoring program. The areas in question are hydraulically bound by Neuse River and/or its
tributaries. No known water supply wells are located in these areas. CORPUD and North Carolina
Division of Forest Resources own a majority of the land in these areas. Institutional controls (i.e., deed
restrictions) may be placed to prevent future use of groundwater as a drinking water source. As
previously noted, CORPUD will seek a variance pursuant to 15A NCAC 2L .0113 to allow monitoring in
lieu of active remediation in these areas.
Considering the locations of the current land application permit compliance wells, it is anticipated that
four additional monitoring wells would be required to monitor the groundwater nitrate plume. It is
assumed that approximately 12 monitoring wells and 10 surface water locations will be sampled three
times a year and analyzed for nitrate for the life of the project. In addition, 40 extraction wells will be
sampled and analyzed for nitrates annually for the life of the project. Groundwater data from these
extraction wells, monitor wells, and surface water samples will be used to monitor the performance of
this alternative. It should be noted that currently, the CORPUD samples the compliance wells three
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times a year as part of the compliance monitoring (for the biosolids application permit) for the Site .
Analytical data from these test wells would be used to evaluate the effectiveness of this alternative~ For
the purpose of costing and comparison, it is assumed that the project life of this alternative is 30 years.
The costs to monitor compliance wells (test wells) required under the biosolids permit are not included
in this estimate.
Feasibility
The partial containment alternative is expected to be effective at controlling groundwater containing
nitrates in excess of NCAC 2L groundwater standard from migrating beyond the compliance
boundaries of Fields 50, 500 and 60. As indicated earlier, groundwater extraction is a proven
technology for plume containment in unconsolidated and fractured rock aquifers. As long as the
extraction syst~m is operational, this alternative can effectively contain the nitrate impacted
groundwater in Fields 50, 500 and 60 from migrating beyond the Site's compliance boundary at
concentrations greater than 10 mg/L. Adequate biosolid fields are available for field application (spray
irrigation) of extracted groundwater (except during winter season and during rainfall; irrigation volume
is assumed to be 70 percent). The water that will be field applied (irrigated) is expected to be taken up
by crops (beneficial use of extracted groundwater). During times when irrigation is not practical, the
extracted groundwater will be treated at the NRWWTP. Treatment at the NRWWTP is expected to be
effective in reducing nitrate concentration to discharge limits. Nitrate concentrations in groundwater at
areas considered for variance are expected to decrease over time due to natural processes (such as
dilution, dispersion, and biodegradation).
The extraction system for this alternative can be constructed utilizing standard drilling methods,
equipment and construction techniques. The periodic groundwater sampling associated with the
groundwater extraction system can be easily implemented.
Limitations
This alternative would require long-term maintenance of the extraction system. Some of the extracted
water, estimated to be 115,200 gpd (based on 40 recovery wells and flow rate of 2 gpm per well), may
have to be stored and treated at . the NRWWTP. Due to large length of trenching and piping
(approximately 21,200 ft) to convey water to the treatment plant, construction cost would be high. This
alternative is dependent on approval of a variance request, as described above. It also requires a
modification of CORPUD's residual permit to allow for irrigation of the extracted water. Due to
groundwater withdrawal, this option could reduce base flow to the Neuse River and/or its tributaries.
Probable Costs
The present worth of opinion of probable costs for this alternative is approximately $4,704,200. The
present worth was calculated using a discount rate of 5.125 percent.. Details of the probable cost and
key assumptions are included in Table 2-3. These costs include capital and operational tasks. It should
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be noted that costs to monitor compliance wells (test wells) required under the biosolids permit are not
included in this estimate. It should be noted that these probable costs are for evaluation of alternatives
and actual costs of implementation may vary (typically around -30 to +50 percent).
2.2.1.3
System Process Descri ption
Alternative 3: Groundwater Containment in Fields 50, 500, and 60,
On-Site Treatment and Discharge, and Long-term Monitoring in
Other Areas
This partial containment alternative is similar to the previous alternative and involves containment of
nitrate contaminated groundwater in selected fields using appropriately spaced extraction wells and
aboveground treatment and disposal. The key difference between this alternative and Groundwater
Alternative 2 is that in this alternative, extracted groundwater would be treated on-site using an anion
exchange treatment system.
The number, locations and depths of wells are identical to those of Groundwater Alternative 2. Figure
2-3 presents conceptual layout of the proposed extraction wells and the treatment unit. For the
purpose of CAP, yield from each well is expected to be approximately 2 gpm. Extracted groundwater
will be treated for nitrate using an anion exchange system. The anion exchange unit would be installed
in Field 500. Prior to the anion exchange unit, the extracted water will be passed through a greensand
filter to remove iron and manganese which could potentially foul the anion resin. The effluent from
greensand filter will then be passed through ion exchange resins where nitrate anion (NO3-1 ) will be
exchanged with chloride anion (Cr1). In this alternative, the treated water will be discharged to
Beddingfield Creek through an outfall located near Field 500. A NPDES permit would be required to
discharge the treated water into the Beddingfield Creek. The ion exchange resin will require periodic
regeneration. The regenerant containing high concentration of nitrate is assumed to be periodically
transported to NRWWTP for further treatment and disposal.
As discussed earlier, a variance from 2L requirements to allow for long-term monitoring in lieu of active
remediation would be requested for the remaining areas of the Site, where exceedances of the nitrate
groundwater standard have occurred at or beyond the Site's compliance boundary.
Considering the locations of the current land application permit compliance wells, it is anticipated that
four additional monitoring wells would be required to monitor the groundwater nitrate plume. In addition
to groundwater data from compliance wells, approximately 12 monitoring wells and 10 surface water
locations will be sampled three times a year and analyzed for nitrate for the life of the project. In
addition, 40 extraction wells will be sampled and analyzed for nitrates annually for the life of the
project. Groundwater data from these extraction wells, monitor wells, and surface water samples will
be used to monitor the performance of this alternative. It should be noted that currently CORPUD
samples the test (compliance) wells three times a year as part of compliance monitoring under the
biosolids application permit. Analytical data from these test wells would be used to evaluate the
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System Process Descri ption
This alternative involves injection (pressure or gravity feed) of biodegradable carbon electron donor
(e.g., com syrup or sodium lactate) via injection wells to create in situ anaerobic zones that will denitrify
nitrate in groundwater from Fields· 50, 500 and 60 at the Site. The electron donor (food) injection allows
the populations of native microorganisms to multiply to the point where microbial respiration consumes
the available dissolved oxygen in groundwater. In the absence of dissolved oxygen the microbes will
use nitrate as an electron acceptor and produce nitrogen gas, a process referred to as denitrification.
Nitrate impacted groundwater from the application fields that migrates into the anoxic zone will be
denitrified and exit the anoxic zone with little to no nitrate. In situ denitrification by injecting electron
donor solution has been successfully demonstrated in the field. Examples of field scale demonstration
have been described by Interstate Technology Regulatory Council (ITRC) in their document on
enhanced in-situ biodenitrification of nitrate contaminated groundwater (ITRC, 2000).
Prior to implementing a full-scale in-situ denitrification system,.a pilot test would have to be conducted
to evaluate the effectiveness at the Site and to collect data for full-scale design. Injection wells will be
constructed within the compliance boundaries of the above-referenced fields to reduce nitrate
concentrations in the impacted groundwater. It is anticipated that approximately 195 injection wells
would be required to achieve this control. Injection wells will be properly spaced to allow establishment
of anaerobic zones to support denitrification. A conceptual layout of the proposed injection well
locations is presented in Figure 2-4. It is anticipated that the injection wells will be installed to depths
ranging from 65 to 85 ft using conventional drilling techniques. This process would involve preparing
the electron donor solution by mixing the required amount of electron donor (e.g., com syrup, sodium
lactate) with appropriate amounts of potable water. The electron donor solution would then be
manually injected into injection wells by either gravity feeding or pumping. The remaining areas of the
Site where exceedances of the nitrate groundwater standard have occurred at or beyond the
compliance boundary would be addressed as described in Alternatives 2 and 3 (i.e., long-term
monitoring only).
A field-scale pilot study would be required to estimate the quantities of electron donor solution and to
determine the design parameters (e.g., area of influence, spacing and number of injection wells/points,
frequency of injection) prior to designing a full scale system. The number of injection wells and their
locations will be · adjusted in the implementation phase based on the results of the field-scale pilot
study. For the purpose of costing, it is anticipated that electron donor solution will be injected biweekly
for the first six months of this project. Thereafter, the donor solution will be injected monthly from the
seventh month through to the end of year 5, and semiannually thereafter from year 6 though to year
30.
To monitor effectiveness of this corrective action alternative, approximately 20 monitoring wells,
20 injection wells, and 10 surface water locations will be sampled three times a year and analyzed for
nitrate for the life of the project. In addition, 20 samples will be analyzed annually for biogeochemical
parameters (i.e., ferrous iron, total organic carbon etc.) required to evaluate denitrification/anaerobic
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conditions. It should be noted that currently, the CORPUD samples the compliance wells three times a
year as part of the compliance monitoring. The data from test well sampling will be used for evaluating
performance of this alternative. For the purpose of costing and comparison, it is assumed that the
project life of this alternative is 30 years.
Feasibili ty
This alternative is expected to be effective at reducing nitrate concentrations in groundwater as it
passes through the anoxic reactive zones. Since nitrates are reduced to innocuous compounds (i.e.,
nitrogen and oxygen) in the denitrification process, this remedy optimally provides permanence.
Periodic injections of carbohydrate solution would be required to address dissolved nitrate migration
from the fields. This technology has been used in the wastewater treatment industry and also currently
being used for in-situ remediation of nitrate contaminated groundwater. Nitrate concentrations in
groundwater at areas considered for variance are expected to be reduced due to natural processes
(such as dilution, dispersion, and biodegradation). A field-scale demonstration performed by the
University of New Mexico researchers at a site in Albuquerque, New Mexico, by injecting sodium
acetate (electron donor source) and trimetaphosphate (nutrient) indicated significant nitrate reduction
(to near zero concentration in nearby monitoring well) due to in-situ biodenitrification (ITRC, 2000).
The construction activities required to install injection wells are easily implemented. The process of
injecting the reagents is relatively simple and requires a trained technician. Availability and scheduling
of equipment and supplies are not anticipated to pose problems. Since no groundwater is extracted in
this alternative, no permanent piping would be required as in the other alternatives.
Limitations
Since these processes are in-situ, subsurface biogeochemical conditions will control their
effectiveness. A pilot study would be required to evaluate field effectiveness and to collect site-specific
information to develop design parameters (e.g., area influence, injection well spacing, electron donor
requirements, etc.) for full-scale application of this remedy. This alternative is dependent on approval of
a variance request as described above. This alternative potentially requires new skills and special
training of CORPUD personnel for its operation and maintenance.
Probable Costs
The present worth of opinion of probable costs for this alternative is approximately $3,800,600. The
present worth was calculated using a discount rate of 5.125 percent. Details of the probable cost and
key assumptions are included in Table 2-5. These costs include capital and operational tasks. It should
be noted that costs to monitor compliance wells (test wells) required under the biosolids permit are not
included in this estimate. It should be noted that these costs are for evaluation of alternatives and
actual costs of implementation may vary (typically around -30 to +50 percent).
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2.3 Rationale for Selection of Groundwater Corrective Action Alternative
The key objective of the corrective action is to address groundwater in areas where an exceedance of
nitrate groundwater standard has been observed at or beyond the compliance boundary and where the
current use of the downgradient property is residential. Section 2.2 described four alternatives and
discussed their feasibility, limitations and probable costs. Alternatives 1, 2, and 3 are expected to
provide hydraulic containment of the dissolved nitrate plume, while Alternative 4 is expected to create
an in-situ treatment zone (reactive zone) to reduce dissolved nitrates as the nitrate-impacted
groundwater passes through.
The alternatives evaluated in Section 2.2 are expected to provide similar levels of protectiveness. The
potential for human exposure has been reduced/limited through supply of public or bottled water to
residences and abandonment of water supply wells. The alternatives provide extra protection for
residential areas by containing or treating the nitrate impacted groundwater migrating toward those
residential areas. Nitrate levels in surface water are below the state water quality standard with the
exception of two intermittent drainage swales within Fields 60 and 61 that drain to a· portion of the
Neuse River classed as Water Supply V. The detected nitrate concentrations are not known to be toxic
to aquatic organisms. The primary environmental concern with the elevated nitrate in groundwater is
the added loading of nitrogen to the nutrient sensitive Neuse River. However, even with the additional
loading of nitrogen resulting from exceedances of nitrate standard at or beyond the compliance
boundary, the Site is well within the permit limit of 676,411 lbs/year. The alternatives evaluated are
thus protective of human health and the environment.
Alternative 1 provides containment of the nitrate plume along the portion of the compliance boundary
where nitrate levels exceed 10 mg/L. However, this option is significantly more expensive than the
other alternatives and does not provide significant environmental benefits compared to the other
alternatives. Therefore, this alternative is not cost effective.
Alternatives 2, 3, and 4 involve active containment or in-situ treatment in those areas where
exceedances of the nitrate groundwater standard have occurred at or beyond the compliance
boundary and there are existing residential properties immediately downgradient of those fields (even
though the properties have been connected to the public water supply system). These alternatives
also involve long-term monitoring and a request for variance in the remaining areas where
exceedances of the nitrate groundwater standard have occurred at or beyond the compliance
boundary, but where there are no downgradient residential properties between the fields and a surface
water hydraulic boundary. This approach is not expected to increase potential risks to human health
and environment.
The key difference between Alternatives 2 and 3 is the treatment method for the extracted
groundwater. Nitrate contaminated groundwater will be used for crow growth when irrigated when
treated using biological treatment when applied as irrigation water (crop growth) or at the NRWWTP in
Alternative 2, while on-site treatment system (ion exchange system) will be used in Alternative 3.
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Alternatives 2 and 3 use a conventional approach of hydraulic containment (extraction wells), while
Alternative 4 is an innovative, in-situ treatment method. Alternatives 2 and 3 involve labor intensive
approaches for groundwater extraction and treatment methods and will require significant maintenance
by skilled and certified operators. Alternative 2 has the benefit of allowing flexibility for either irrigation
of the application fields or treatment at the NRWWTP. As stated previously, CORPUD intends to
irrigate all of application fields as a best management practice to enhance crop growth/yields. Since
CORPUD already has operators to manage irrigation and treatment at the NRWWTP, no significant
training would be required to operate the system. Alternative 3 commits CORPUD to a new point of
discharge on Beddingfield Creek and to operation of a new treatment plant with a unique treatment
train very different from the NRWWTP operation.
Alternative 4 involves manual mixing and injection of electron donors which would require trained
personnel (not skilled or certified). However, Alternative 4 is an in-situ method and a pilot test would
be required to evaluate its effectiveness and development of design data prior to implementing a full-
scale system. Alternative 4 has the benefit of not generating new discharge water, but will require
development of new, specialized skills and operating procedures to maintain the in situ treatment zone.
Alternative 1 has the highest probable implementation costs. Alternative 3 would cost more than
Alternatives 2 and 4, since it involves on-site treatment of the extracted water using anion exchange
system. The estimated present worth cost for implementation of Alternative 4 is the lowest among the
alternatives evaluated.
Based on the discussion presented above, Alternative 2, Groundwater Containment in Fields 50, 500
and 60, Discharge to NRWWTP or Land Application and Long-Term Monitoring in Other Areas
appears to be the most appropriate groundwater corrective action alternative. This alternative is
expected to mitigate the dissolved nitrate plume at Field 50, 500, and 60 where migration into
residential areas may occur. It is most consistent with the goal of implementing the irrigation best
management practice and allows for flexibility for treating the excess water at the NRWWTP. No new
technology, special training or unique treatment will be needed to implement this alternative
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2-12
3.0 PROPOSED CORRECTIVE ACTION
The proposed corrective action alternative for treatment of nitrate impacted groundwater at the Site is
Alternative 2, i.e., Groundwater Extraction in Fields 50, 500, and 60 with Discharge to NRWWTP or
Land Application (irrigation) and Long-term Monitoring. This alternative is expected to control migration
of nitrate impacted groundwater on to the off-site residential properties from the above-mentioned
fields. With respect to the remaining areas of the Site where exceedances of the nitrate groundwater
standard have been observed at or beyond the compliance boundary, there are no downgradient
residential properties between the fields and a surface water hydraulic boundary. Under this
alternative, long-term monitoring only is proposed for those areas and CORPUD proposes to seek a
variance from the Environmental Management Commission to allow for such monitoring in lieu of
active remediation.
Groundwater extraction is a proven technology for plume containment in unconsolidated and fractured
rock aquifers. The extracted groundwater from Fields 50, 500, and 60 will be applied to selected fields
as irrigation water or pumped to the NRWWTP for treatment. CORPUD will soon request a permit
modification to add 140 more acres for irrigation. A conservative estimate is that the currently
permitted 105 acres for irrigating the reclaimed wastewater would be sufficient to absorb the extracted
groundwater. For the purposes of this evaluation it is assumed CORPUD will irrigate 70% of the
extracted groundwater and route the remaining 30% to the NRWWTP on an annual basis. Nitrate
concentrations in groundwater in areas considered for variance are expected to decrease over time
due to natural processes (such as dilution, dispersion, and biodegradation).
The key components of this remedy are a network of extraction wells and monitoring wells, and the
associated piping/pump system for pumping the extracted wastewater to NRWWTP for treatment or to
selected fields for irrigation. Details of the design criteria, groundwater extraction well network, and
monitoring program are described in the following sections:
3.1 Design Criteria
The groundwater extraction system proposed in this CAP is based on the following design criteria:
• Based on the information collected during CSA and SSA, the Site is located in the eastern
Piedmont of North Carolina. The nitrate contamination in groundwater appears to be limited to
the saprolite and partially weathered rock (PWR) zones and upper fractured bedrock zone of
the aquifer system at the Site. Therefore, the proposed extraction wells and monitoring wells
will be installed to penetrate these two zones. The lower unfractured bedrock zone does not
appear to have been impacted with nitrates.
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• The groundwater flow modeling used to determine the capture zone and design the extraction
well network assumes that the groundwater flow rate from each extraction well is 2 gpm
(Appendix A).
• The number and locations of the proposed extraction wells are based on the capture zones
estimated in the groundwater flow and transport modeling to provide proper hydraulic
containment of nitrate impacted groundwater at Fields 50, 500 and 60. Conceptually, the ·
extraction well spacing is estimated to be approximately 100 feet.
3.2 Groundwater Extraction System Implementation
To implement and properly evaluate the groundwater extraction system, extraction wells and
monitoring wells will be required. Extraction wells and monitoring wells will be installed in accordance
with applicable regulations of NCDENR. Extraction wells will be installed in Fields 50, 500, and 60 at or
near their compliance boundaries to provide hydraulic containment of the dissolved nitrates in these
fields and mitigate their migration on to the off-site residential properties. A piping system will be
installed along roads or through fields for discharge of the extracted groundwater to the NRWWTP.
The extracted water will be used for irrigation and/or treated at the plant.
Existing groundwater monitoring wells in the three fields will be used for performance monitoring of the
extraction system. Analytical data from the compliance wells along with some selected existing
monitoring wells and proposed monitoring wells would be used for long-term monitoring of the areas
included under the variance request. Figure 2-2 presents a conceptual layout of the proposed
groundwater extraction wells and the associated piping/pump system. Details of the proposed system
are outlined in the following sections.
3.2.1 Extraction Well and Monitoring Well Layout
The proposed extraction wells would be installed linearly and along the compliance boundaries in the
active treatment fields (i.e., Fields 50, 500, and 60) (see Figure 2-2). As indicated in Section 3.1,
number and spacing of extraction wells is based on the groundwater flow modeling analysis. The
spacing between extraction wells is estimated to be approximately 100 ft. It is estimated that
approximately 7 extraction wells would be installed in Field 50, 22 extraction wells would be installed in
Field 500, and 11 extraction wells would be installed in Field 60. In addition, four additional monitoring
wells would be installed in selected fields/areas for long-term monitoring of the areas included in the
variance request. Actual number of extraction and monitoring wells, spacing, location, depth, and
screened intervals may be adjusted based on Site conditions.
3.2.2 Extraction Well and Monitoring Well Installation
Extraction wells and monitoring wells will be installed by a North Carolina licensed driller. The wells will
be installed using hollow stem auger or mud-rotary. It is estimated that the extraction wells in Field 50
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would be installed to a depth of approximately 80 ft bsg and extraction wells in Fields 500 and 60
would be installed to a depth of approximately 60 ft bsg to penetrate layers 1 and 2 of the aquifer
system. The proposed monitoring wells used for long-term monitoring of certain areas included under
variance request may have to be installed beyond the Site's compliance boundary. The depth of the
proposed monitoring wells is estimated to be approximately 70 ft bsg. Individual well depths will be
determined based on actual Site conditions (e.g., soil lithology).
The wells would be designed to minimize the aquifer material (fines) from entering the well by properly
sizing the well screen and filter pack material. The extraction wells would be constructed of Schedule
40, 6-inch diameter polyvinyl chloride (PVC) wire-wrapped or equivalent screen and casing. The
proposed monitoring wells would be constructed of Schedule 40, 2-inch diameter PVC wire-wrapped
or equivalent screen and casing. The extraction well screens will have a 0.020-inch slot size and the
monitoring well screens will have a 0.010-inch slot size. The extraction and monitoring wells will have
an approximately 20-foot screen. The annular space between the well screen and the borehole will be
backfilled with an appropriately sized silica sand filter pack to one foot above the screen. A 2-foot thick
bentonite seal will follow the filter pack. The balance of the annular space will then be backfilled with a
cement grout. Following installation, . all wells will be identified with permanent well identification
markings or tags. It is anticipated that the extraction and monitoring wells will be completed flush
grade and protected with steel vaults.
3.2.3 Collection Piping System Layout
The conceptual layout of the proposed piping system from the extraction wells to NRWWTP is
depicted in Figure 2-2. It is anticipated that the piping system will be installed underground along Old
Baucom Road, Mial Plantation Road, and along selected roads/driveways between certain fields. The
preliminary design of piping system is such that it avoids most of the wooded areas located between
the application fields (determined from the aerial photograph provided by CORPUD). It is estimated
that 1 equalization tank and 2 lift stations/booster stations may be required to convey the extracted
groundwater to the NRWWTP. The piping system layout will be modified based on the field conditions
during the detailed design phase and during field implementation. The detailed design phase will also
include design and specifications of the equalization tank and lift stations, if required.
The main collection pipe is estimated to be a 6-inch diameter Schedule 40 PVC pipe installed along
Old Baucom Road between . Fields 50 and 500. The individual collection pipes carrying extracted
groundwater from Fields 50 and 500 would be connected to the central collection pipe at select
locations on Old Baucom Road. In addition, it is anticipated that the individual collection pipe carrying
extracted groundwater from Field 60 would be installed along Mial Plantation Road and would be
connected to central pipe at the intersection of Mial Plantation Road and Old Baucom Road. It is
estimated that the individual collection pipes Will be 2-inch diameter Schedule 40 PVC pipes. The
layout of the central collection pipe from Old Baucom Road to the discharge point in NRWWTP is
approximately as depicted in Figure 2-2.
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Prior to construction of the collection piping system, a Right-of-Way Encroachment Agreement Form,
may have to be submitted to North Carolina Department of Transportation (NCDOT), Wake County,
Raleigh Office, for approval along with detailed collection system design plans. The implementation of
the proposed collection piping system will be subject to the approval of NCDOT.
It should be noted that this alternative also involves land application of the reclaimed wastewater in
selected application fields. In order to retain the flexibility for CORPUD to use any of the available
application fields for irrigation, this preliminary design does not include the layout of proposed piping
system for spray irrigation to any individual field.
3.2.4 Recovery Pump Selection
Groundwater will be extracted from extraction wells using submersible electric pumps. It is . estimated
that the extraction wells can be pumped at a rate of 2.0 gpm. The proposed layout of the piping system
as depicted in Figure 2-2 was subdivided into sections for calculation of estimated friction losses.
Preliminary calculation of friction losses, estimation of total dynamic head and pump selection are
provided in Appendix B. Based on the required dynamic head and the estimated flow rates, a Grundfos
Redi-flo 5E12 submersible pump with 0.5 HP is proposed to be used in the extraction wells. The
pumps will be operated based on water level in the well and controlled by individual level switches.
3.3 Proposed Groundwater Monitoring and Reporting
A groundwater monitoring program will be implemented to evaluate performance of the extraction
system and the variance areas. The program will involve sampling groundwater from key existing
monitoring wells as well as the additional monitoring wells installed as part of the variance request. In
addition, approximately 40 extraction wells and surface water locations (approximately 10 surface
water locations) will be included in the sampling program to evaluate the effectiveness of the system.
The following section discusses the proposed groundwater monitoring strategy including parameters to
be monitored both in the field and in the laboratory.
Monitoring and Reportin g Freq uency
Prior to start up of the extraction system, a baseline monitoring well sampling event be performed.
Performance monitoring will be performed periodically. As discussed earlier, existing selected
monitoring wells (e.g., MW-105, MW-108, MW-109) located in Field 50, 500, and 60 will be used for
performance monitoring in these fields. Four proposed monitoring wells that will be installed for long-
term monitoring of the areas included in variance request will be included in the monitoring program
(refer to Figure 2-2). In addition, 40 extraction wells and 10 surface water locations will be sampled
during the monitoring program. During the sampling events, field parameters (e.g., dissolved oxygen,
pH, temperature) would be collected from the sampled wells using a · multi-parameter meter.
Groundwater and surface water samples collected during baseline and performance monitoring events
will be analyzed for nitrate. The sampling events will be performed three times a year to coincide with ,
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3-4
the CORPUD groundwater compliance sampling program under land application permit (sampling of
test wells). The extraction well sampling would be performed only once a year (annually). Table 3-1
presents a summary of the proposed groundwater sampling program.
The field and laboratory data obtained during .each sampling event will be compiled into groundwater
monitoring report that will be submitted to NCDENR three times a year. This report will include a
general description of the overall performance of the treatment-system, and a description of any major
or proposed changes to improve the performance of treatment system.
3.4 Permitting
A groundwater extraction well installation permit will be obtained from NCDENR. To use extracted
groundwater for irrigation of selected fields, a modification to the existing land application permit will be
required. The permit modification process will be initiated upon approval of the CAP. The corrective
action would be initiated after approval of the permit modification.
3.5 Notifications/Access Agreements
A Right-of-Way Encroachment Agreement Form may have to be submitted to NCDOT for their
approval of the proposed collection piping system. The corrective action would be initiated after
approval of the notification.
In addition, CORPUD may require access agreements to install the proposed monitoring wells beyond
the Site's compliance boundary. These monitoring wells will be used for long-term monitoring of select
areas included in the variance request.
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4.0 REFERENCES
Daniel, Ill, C.C. and P.R. Dahlen, 2002. Preliminary Hydrogeologic Assessment and Study Plan for a
Regional Ground-Water Resource Investigation of the Blue Ridge and Piedmont Provinces of
North Carolina. U.S. Geological Survey Water-Resources Investigations Report 02-4105.
Daniel Ill, C.C. and Payne, R.A., 1990. Hydrogeologic Unit Map of the Piedmont and Blue Ridge
Provinces of North Carolina. US Geological Survey Water-Resources Investigations Report
90-4035, Raleigh, NC.
ECS, 2002a, Report of Investigations, Neuse River Wastewater Treatment Plant.
ECS, 2002b, Results of Drinking Water Supply Well Sampling.
ENSR, 2002, Comprehensive Site Assessment, City of Raleigh, Neuse River Waste Water Treatment
Plant, December.
ENSR, 2003, Supplemental Site Assessment, City of Raleigh, Neuse River Waste Water Treatment
Plant, December.
Hamed and Daniel, . 1989, The Transition Zone Between Bedrock and Regolith: Conduit for
Contamination?, Proceedings of a Conference on Groundwater in the Piedmont of the Eastern
United States, October 1989.
ITRC, 2000, Technology Overview, Emerging Technologies for In-Situ Biodenitrification (EISBD) of
Nitrate Contaminated Groundwater, prepared by Interstate Technology and Regulatory
Cooperation Work Group.
May, V. J., and Thomas, J. D., 1965, North Carolina Department of Water and Air Resources, Division
of Groundwater and the United States Department of the Interior, Geological Survey.
Groundwater Bulletin 15 Groundwater Geology and Groundwater Resources in the Raleigh Area
North Carolina, Raleigh, NC.
NCDENR, July 2002, Groundwater Section Guidelines for the Investigation and Remediation of Soil
and Groundwater.
Parker, J.M., 1979, Geology and Mineral Resources of Wake County, North Carolina Department of
Natural Resources and Community Development, Geological Survey Section, Bulletin 86, 122
pp.
S:\PUBS\PROJECnRIRaleigh_City of\CAP Work\CAP Report\Text\Flnal CAP Report 020805.doc February, 2005
4-1
Wilson, W. F., and Carpenter, P.A., 111, 1981. Region J Geology: A Guide to North Carolina Mineral
Resource Development and Land Use Planning. Regional Geology Series 1. North Carolina
Department of Natural Resources and Community Development, Geological Survey Section,
Raleigh, NC.
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February, 2005
( TABLE 1-2
Soil Analytical Results
City of Raleigh, Neuse River Wastewater Treatment Plant
Raleigh , North Carolina
Sample ID/ Field Sample Ammonia Nitrate Nitrite Solids
Depth Location Date (m g /kg) (mg/kg) (mg/kg) (%)
SB-1 0-7" Field 3 12/12/02 1.3 2.9 <1.0 82
SS-1 0-4' Field 3 11/14/02 1.1 9 <1 80
SS-1 4-8' Field 3 11/14/02 <0.1 9.4 <1 82
SS-1 8-12' Field 3 11/14/02 0.14 16 <1 79
SS-1 12-16' Field3 11/14/02 0.1 18 <1 90
SS-116-22' Field 3 11/14/02 <0.1 16 <1 89
SB-2 0-7" "Field 3 12/12/02 1.1 4.1 <1.0 82
SS-2 0-4' Field3 11/14/02 0.6 7 .9 <1 84
SS-2 4-8' Field 3 11/14/02 <0.1 24 <1 72
SS-2 8-12' Field 3 11/14/02 <0.1 8.1 <1 93
SS-2 12-14' Field3 11/14/02 <0.1 5.9 <1 94
SB-3 0-7" Field 100 12/12/02 1.1 8.1 <1.0 81
S83 0-4' Field 100 11/15/02 0.58 23 <1 81
S83 4-8' Field 100 11/15/02 0.43 58 <1 67
S83 8-12' Field 100 11/15/02 3.1 51 <1 77
S83 12-16' Field 100 11/15/02 0.32 24 <1 84
S8316-20' Field 100 11/15/02 0.36 26 <1 86
S83 20-24' Field 100 11/15/02 0 .29 17 <1 90
SB-4 0-7" Field 100 12/12/02 2.2 5.6 <1.0 82
S84 0-4' Field 100 11/15/02 1 .. 1 26 <1 84
S84 4-8' Field 100 11/15/02 0.37 61 <1 75
S84 8-12' Field 100 11/15/02 0.94 30 <1 83
S84 12-16' Field 100 11/15/02 0.39 19 <1 72
S8416-20' Field 100 11/15/02 <0.1 27 <1 84
SB-5 0-7" Field 500 12/23/02 2.5 <1.0 <2.0 83
S85 0-4' Field 500 11/15/02 0.67 3.5 <1 78
S85 4-8' Field 500 11/15/02 <0.1 25 <1 84
S85 8-12' Field 500 11/15/02 <0.1 8.9 <1 84
S85 12-16' Field 500 11/15/02 <0.1 14 <1 85
S85 16-24' Field 500 11/15/02 <0.1 9.4 <1 80
SB-6 0-7" Field 500 12/12/02 0.98 2.4 <1.0 88
S86 0-4' Field 500 11/15/02 0.6 5 <1 88
S86 4-8' Field 500 11/15/02 <0.1 16 <1 82
S86 8-12' Field 500 11/15/02 0.6J 10 <1 82
D-S86 8-12' Field 500 11/15/02 0.23J 9.9 <1 83
S86 12-16' Field 500 11/15/02 <0.1 11 <1 83
S86 16-20' Field 500 11/15/02 <0.1 12 <1 79
Notes:
TKN -Total Kjeldahl Nitrogen
TOC -Total Organic Carbon
mg/kg -Milligrams per kilogram
J -Estimated value
NA -Not Analyzed
Tables 1-2 through 1-5.xls\T1-2 Soil Results
TKN TOC
(m g /kg) (m g /kg)
1600 NA
920 NA
14 NA
9.3 NA
5.1 NA
2.2 NA
1800 NA
480 NA
24 NA
9.2 NA
6.5 NA
1800 NA
80 870
28 400
27 8530
18 400
8.8 383
<0.06 296
1600 NA
69 2260
32 209
14 522
9.2 3130
3.1 331
1800 NA
460 6310
37 296
9.6 278
<0.06 70
<0.06 90
650 NA
670 3860
51 783
20 679
16 278
31 574
<Q .06 350
Page 1 of 1
Field
Sam p le ID ID
TestWell 1 Field 12
TestWell2 Field 28/32
TestWell 3 Field 49
TestWell 4 Field 50
TestWell 9 Field 39
TestWell 11 Field 3
TestWell 13 Field 42
TestWell 14 Field 33
TestWell 15 Field 16
TestWell 16 Field 35
TestWell 18 Field 27
TestWell 20 Field 20
TestWell 22 Field 16
TestWell 23 Plant
TestWell 24 Plant
TestWell 25 Field 44/45
TestWell 29 Field 29
TestWell 30 Field 602
TestWell30.1 Field 602
TestWell 31 Field 602
TestWell 32 Field 602
TestWell 33 Field 602
TestWell 34 Field 602
TestWell 35 NA
Test Well 36 Field 602
TestWell 37 Field 602
TestWell 41 Field 3
TestWell 42A Field 18/19
Test Well 43 Field 25
TestWell 44 Field 26
TestWell 45 Field 47
TestWell 46 Field 61
TestWell 47 Field 61
TestWell 48 Field 60
Test Well 49 Field 74
TestWell 50 Field 75
Test Well 51 (1) Field 12
Test Well 52 /1 l Field 41
Test Well 53 11) Field 62
Test Well 54 (1) Field 503
TestWell 641 Field 602
TestWell 642 Field 602
TestWell 31A Field 602
TestWell 32A Field 602
TestWell 45A Field 47
TestWell 61B Field 61
TestWell 61C Field 61
15A NCAC 2L Standard
Notes:
TABLE 1-3
Groundwater Analytical Results -City Test Wells
City of Raleigh, Neuse River Wastewater Treatment Plant
Raleigh, North Carolina
Nitrate Concentration (ma ll)
March 2003 Julv 2003 November 2003 March 2004
ns 32.0 13 .0 ns
ns 16 .7 9.8 ns
<0.01 <0.1 0.1 <0.1
ns 0.6 ns ns
ns 168.6 ns ns
ns 9.5 9.9 ns
0.1 3.4 2 .1 <0.1
ns 0.6 5 .5 ns
ns 37.3 27.8 ns
ns 8.7 3.1 ns
ns 179.5 130.6 ns
1.9 2.2 8.3 2.5
0.1 0.2 0.2 ns
ns ns 12 .8 ns
ns ns 5.8 ns
ns ns 0.1 ns
ns 21.8 ns ns
ns 5.8 7 .5 ns
ns 5.8 ns ns
0.1 <0 .1 0.2 0 .2
ns 3.8 4.8 ns
ns 5.8 6.1 ns
ns 49.6 ns ns
ns 26.6 ns ns
ns 4.3 3.2 ns
ns 2.4 0.4 ns
0.6 87.8 15.5 82.7
107.8 87.2 2.3 114.7
0.1 <0.1 3.5 ns
7 .5 2.9 2 .3 5 .6
15.4 9.6 74 .8 9 .6
15 .2 1.8 1.6 1.7
30.9 31 .2 32.2 35.3
50 .6 43.0 51.9 56.8
0 .5 0.4 0.7 1.4
5.6 37.7 7.5 31.2
ns ns ns ns
ns ns ns ns
ns ns ns ns
ns ns ns ns
ns 62.8 ns ns
ns 79.4 ns ns
ns 33.6 ns ns
ns 15.8 ns ns
ns 5.4 ns ns
ns 2.2 ns ns
ns 3.5 ns ns
10
1) Test Wells 51, 52, 53, 54 were previously identified as GP-2, GP-7, GP-11, and GP-20, respectively .
mg/L -Milligrams per Liter
na -not analyzed .
ns -not sampled .
NA -Information Not Available
Tables 1-2 through 1-5.xls\T1-3 City Test Wells
July 2004 November 2004
ns ns
ns ns
ns ns
ns ns
ns ns
ns ns
4 .7 1.9
ns ns
ns ns
ns ns
ns ns
3.4 9.3
0.7 <0.1
ns ns
ns ns
ns ns
ns ns
ns ns
ns ns
ns ns
ns ns
ns ns
ns ns
ns ns
ns ns
ns ns
87.1 /84.9 77 .3 / 77.4
120.8/ 111.7 113 .2 / 113.6
ns ns
4.9 5.0
17.7 / 24.7 34 .4/ 24.1
4 .0 1.2
36.353/34.743 34 ;1 / 35.9
57.3 / 55.7 54.2 / 53.
4 .2 1.4
34.9/ 34.5 28.7 / 28.5
107.8 / 101 .4 101 .8 / 95.7
79.9/ 75.4 79 .1 / 74.5
92.3 / 68 .4 78.6/63.3
67.7 / 73.8 56 .1 / 60 .2
ns ns
ns ns
ns ns
ns ns
ns ns
ns ns
ns ns
Page 1 of1
TABLE 1-4
Groundwater Analytical Results -CSA-SSA -Monitoring Wells
City of Raleigh, Neuse River Wastewater Treatment Plant
Raleigh, North Carolina
Nitrate (mg/L)
Well ID Location November/
December June 2003 July 2003
2002
MW-100 Field 18 12 15 NA
MW-101 Field 31 160 120 NA
MW-101D Field 31 100 J 97 NA
MW-102 Field 37 86 72 NA
MW-103 Field 46 49 36 NA
MW-104 Field 70 24 35 NA
MW-105 Field 50 11 17 NA
MW-105D Field 50 28J 23 NA
MW-106 Field 75 2.5 17 NA
MW-106 (Du o) Field 75 NA 18 NA
MW-107 Field 75 <0.1 0.12 NA
MW-108 Field 75 4.4 18 NA
MW-109 Fiel.d 500 54 52 NA
MW-110 Field 500 33 29 NA
MW-111 Field 500 28 17 NA
MW-111D Field 500 18 see packer test results below
.MW-112 Field 201 15 11 .NA
MW-113D Material Recov. 21 J 53 NA
MW-114 Field 63 NA 2.6 NA
MW-115 Field 62 NA 22 NA
MW-116 Field 62 NA 5.5 NA
MW-117 Belvin NA 0.26 NA
MW-118 St. James Sub. NA NA 4.3
MW-119 St. James Sub. NA NA 0.65
MW-120 King NA <0.05 NA
MW-121 Field 600 NA 0.38 NA
MW-122 Field 70 NA 5 NA
MW-122D Field 70 NA 1.7 NA
MW-123D Field 12 NA 120 NA
MW-124D Field 26 NA 0.29 J NA
MW-124D (Du p) Field 26 NA 0.18 J NA
MW-125D Field 600 NA 12 NA
MW-126D Field 61 NA 6.5 NA
MW-127 Field 71 NA <0.05 NA
GP-1 Field 19 22 18 NA
GP-2 Field 12 77 110 NA
GP-2 (Duo) Field 12 74 NA NA
GP-3 Field6 44 6.6 NA
GP-5 Field 11 29 46 NA
GP-6 Field 6 54 35 NA
GP-7 Field 41 58 70 NA
GP-8 Field 63 96 93 NA
GP-9 Field 43 6.7 NA NA
GP-10 Field 48 0.8 0.55 NA
GP-11 Field 63 40 78 NA
GP-12 Field 62 0.12 <0.05 NA
GP-16 (1) Field 500 60 NA NA
GP-17 Field 500 <0.1 6.8 NA
GP-18 (1) Field 500 0.87 NA NA
GP-19 (1) Field 500 <0.1 NA NA
Tables 1-2 through 1-5.xls\T1-4GW -Nitrate
March/April
2004
15.1
164.1
NS
96.1
36.4
43.8
NS
NS
NS
NS
NS
27.2
NS
31.8
16.7
NS
7.8
NS
2.4
32.1
7.9
NS
NS
3.1
0.4
NS
NS
NS
70.0
NS
NS
NS
NS
NS
NS
84.2
NS
NS
55.5
NS
69.0
42.3
24.7
0.4
78.7
0.2
NS
NS
NS
NS
Page 1 of2
TABLE 1-4
Groundwater Analytical Results -CSA-SSA -Monitoring Wells
City of Raleigh, Neuse River Wastewater Treatment Plant
Raleigh, North Carolina
Nitrate (mg/L)
Well ID Location November/
December June 2003 July 2003
2002
GP-20 Field 503 180 62 NA
GP-21 Field 75 2.2 1.9 NA
GP-22 Field 74 130 6.9 7.3
MW-1 (MAT REC ) Material NA NA 2.2
MW-3 Recovery NA 53 NA
MW-5 Property NA 0.1 NA
TW-1 Field 12 NS NS NS
TW-11 Field 3 NS NS NS
TW-18 Field 27 NS NS NS
TW-44 Field 26 NA 2.3 NA
TW-48 Field 60 NA 47 NA
TW-30 Field 601-602 NS NS NS
TW-30.1 Field 601-602 NS NS NS
TW-31A Field 601-602 NS NS NS
TW-32 Field 601-602 NS NS NS
TW-32A Field 601-602 NS NS NS
TW-33 Field 601-602 NS NS NS
TW-34 Field 601-602 NS NS NS
TW-35 Field 601-602 NS NS NS
TW-36 Field 601-602 NS NS NS
TW-37 NS NS NS
PZ-1 Neuse River 0.43 NA NA
PZ-2 Neuse River <0.1 NA NA
PZ-3 Neuse River 22 NA NA
PZ-4 Neuse River 0.12 NA NA
Packer Testing Results
MW-111 D-60-90FT Field 500 NS 19 NS
MW-111 D-90-120FT Field 500 NS 20 NS
PW-39: HEATER-1-40-70Fl St. James Sub . NS 11 NS
=>W-39: HEATER-1-70-100F St. James Sub. NS 6.7 NS
PW-8: {53-72') B. Blowe Res . 20 NS NS
PW-8: (105-135) 8. Blowe Res . 20 NS NS
PW-8: (230-290) 8 . Blowe Res . 20 NS NS
15A NCAC 2L Standard 10
Notes:
1) Well decommissioned.
March/April
2004
NS
NS
NS
NS
NS
NS
38.5
4.9
181.8
NS
NS
11.0
5.7
43.9
2.6
16.4
5.4
64.8
37.4
3.5
2.3
NS
NS
NS
NS
NS
NS
NS
NS
NS
NS
NS
MW -monitoring well; TW -test well; GP -geoprobe point: PZ -piezometer; PW -private well.
J -Estimated value
Dup -Field duplicate sample
NA -Not analyzed / NS -Not sa mp led
Tables 1-2 through 1-5.xls\T1-4GW -Nitrate Page 2 of2
TABLE 1-5
Surface Water Analytical Results
City of Raleigh , Neuse River Wastewater Treatment Plant
Raleigh, North Carolina
Nitrate (mg/L)
Location November 2002 June2003
SW -1 52 49
SW-2 0.39 13
SW-3 52 50
SW-4 54 47
SW-5 0.69 2
SW-6 54 46
SW-7 77 83
SW-8 1.2 1.6
SW-9 34 36
SW-10 48 19
SW-11 19 47
SW-12 52 41
SW-13 0.46 1.3
SW-14 0.21 0.16
SW-15 20 20
SW-16 1.7 6.2
SW-17 5.5 0.97
SW-18 3 1.7
SW-19 16 21
SW-20 3.8 3.3
SW-20 du p 3 .5 NS
SW-21 0.15 0.18
SW-22 0.25 1.5
SW-23 0.72 NS
SW-24 0.53 0.52
SW-25 NS 4.6
SW-26 NS 9.8
SW-27 NS 14
SW-28 NS 46
Notes:
mg/L -Milligrams per Liter
NS -Not Sampled
Dup. -Duplicate sample
Tables 1-2 through 1-5.xls\T1-5 SW -Nitrate Page 1 of 1
Table2-2
Opinion of Probable Costs to Install and Operate a Groundwater Extraction System along the Site Compliance Boundary
with Discharge to the NRWWTP (Alternative 1)
Corrective Action Plan
Neuse River Wastewater Treatment Plant
Raleigh, North Carolina
DESCRIPTION NOTES UNITS QTY UNIT COST TOTAL COST
($) {$)
I. Design Services
1. Project Management/Coordination al Is $13,900 $13,900
2. Additional Groundwater Modeling (to finalize recovery wells) bf Is $10,000 $10,000
3. Engineering Design/Work Plan/Contract Docments Preparation/HASP c/ Is $75,000 $75,000
4. Regulatory Negotiations/Meetings Is $5,000 $5,000
5. Access Agreements/Negotiations Is $30,000 $30,000
6. Pre-bid Meeting/Contractor Selection/Contracting Is $5,000 $5,000
Subtotal Design Services Costs $138,900
7. Contingency (20% of Design Services Costs) Is $27,800 $27,800
Total Design Services Costs $166,700
PW of Total Design Services Costs d/ $158,600
(Distribution in Year 1)
II. Construction and Startup Costs
1. Construction Costs
1. Mobilization/Demobilization/Setup Is $25,000 $25.000
2. Site Clearance/Temporary Road Construction e/ Is $75,930 $75,930
3. Installation of GW Ews along Comp. Boundary (where required) fl ea 426 $5,950 $2,534,700
4. Additional Groundwater Monitoring Wells Installation g/ ea 4 $2,450 $9,800
5. IDW Disposal (drilling cuttings/non-hazardous) cy 982 $55 $54,010
6. Extraction Well vaults (abovegrade) and guardposts ea 426 $1,210 $515,460
7. Extraction Well pumps and Level Switches h/ ea 426 $2,320 $988,320
8. Well Head Fittings, and Valves, and Instrumentation i/ ea 426 $750 $319,500
9. Trenching {for groundwater recovery pipe installation) j/ If 60000 $3 $174,730
1 o. Backfilling trenches cy 8890 $2 $17,780
11. Extraction well piping If 29820 $7 $208,740
12. Equalization Tank (polyethylene) and Transfer Pump k/ Is 10 $4,400 $44,000
13. Lift-stations/Booster Stations V Is 6 $23,000 $138,000
14. GW Piping to Treatment Plant ml If 60000 $20 $1,200,000
15. Expansion of NRWWTP for treatment of extracted water aa/ gal 1226880 $3.50 $4,294,080
16. As-built survey Is $50,000 $50,000
17. Site Cleanup/Restoration Is $10,000 $10,000
18. Electrical hookup/wiring nl Is $270,000 $270,000
19. Electrical Control Panel (groundwater extraction/discharge system) ac/ ea 10 $25,000 $250,000
Subtotal Construction Costs $11,180,050
2. Engineering Services
1. Record Drawings/Construction Report/O&M Manual Is $60,000 $60,000
2. Engineering Oversight (labor and expenses) o/ Is $171,000 $171,000
3. System startup/shake down Is $50,000 $50,000
4. Project Management/Coordination al Is $28,100 $28,100
Subtotal Engineering Services Costs $309,100
3. Contingency (20% of Capital Costs) $2,297,830
Total Construction and Engineering Services Cost $13,786,980
PW of Construction and Engineering Services Cost d/ $12,476,500
(distribution in Yr.2)
Probable Cost Estimates for GW Alternatives.xis Page 1 of3
Table 2-2
Opinion of Probable Costs to Install and Operate a Groundwater Extraction System along the Site Compliance Boundary
with Discharge to the NRWWTP (Alternative 1)
Corrective Action Plan
Neuse River Wastewater Treatment Plant
Raleigh, North Carolina
DESCRIPTION NOTES
Ill. Operation, Maintenance, and Monitoring (OMM)Costa
a. Annual O&M and Monitoring (30 years)
1. System O&M (Yr.1 through 30)
a. Project Management/sub oversight a/
b. System O&M labor/expenses p/
C. Treatment of extracted water at NRWWTP ab/
d. Electrical Power qi
e. Equipment Repair/Replacement
f. Data review/engineering support
Subtotal Annual O&M Cost
2. Triennial Groundwater and Surface water Monitoring
a. Project Management/Coordination a/
b. Labor -sampling r/
C. Analyticals: 26 samples including QNQC samples per event rl
d. Analyticals: BB EW samples + QNQC (annual) r/
e. Equipment rental/Reimbursable
f . Monitoring report to Agency
g. Regulatory Negotiations/Meetings
Subtotal Annual Monitoring Cost (annual)
3. Contingency (20% of Annual O&M and Monitoring Costs)
Total Annual OMM Cost
PW of Annual OMM for Years 1 thru' 30 d/
(distribution in Yrs .2 thru' 32)
V, Decommissioning Costa
1. a. Project Management/Coordination a/
b. Abandon Extraction Pumps/discharge piping s/
C. Abandon Extraction and Monitoring Wells s/
C. Labor/expenses
d. Regulatory Negotiations/Meetings
e. Closure Report
Subtotal Decommissioning Costs
2. Contingency (20% of Annual Decommissioning Costs)
Total Decommissioning Costs
PW of Decommissioning Costs (Years 30) di
(distribution in Yr. 32)
PW OF TOTAL PROBABLE COSTS d/
Noles/Key Assumpstions:
a/ Project management and coordinating all project related activitities.
b/ Requires additional capture zone & fate and transport modeling to design well locations.
cl Detailed design of the remediation system for equipment selection and construction.
UNITS
Is
ea
MG
kw-hr
Is
ea
Is
ea
ea
ea
ea
Is
Is
Is
Is
If
Is
Is
Is
QTY UNIT COST TOTAL COST
($) ($)
$57,300 $57,300
28 $2,550 $71,400
448 $750 $335,860
958,075 $0.10 $95,810
$25,000 $25,000
12 3,740 $44,BBO
$630,250
$8,500 $8,500
3 $8,000 $24,000
78 $15 $1,170
100 $15 $1,500
3 $2,500 $7,500
3 $15,000 $45,000
1 $5,000 $5,000
$94,000
$144,850
$869,100
$12,529,800
$48,600 $48,600
$100,000 $100,000
27900 $6 $167,400
1 $9,000 $9,000
$5,000 $5,000
$10,000 $10,000
$340,000
$68,000
$408,000
$82,400
$25,246,300
d/ Present worth costs were estimated based on a net annual discount rate of 5.125% (normaly used by the City), assuming year-end distribution.
e/ Assume 1 O acre of tree/shrub clearance for piping/weft Installation and 2500 feet of gravel road for access to drill rig.
fl Assume 426 Extraction Wells (EW) in areas where nitrates exceeds 2L standards beyond the compliance boundary (100-ft spacing)
baaed on flow modeling. Wells are assumed to be constructed of 6-in dia PVC casing and screen.
The avg. depth of wells is considered to be 70 ft with 40-ft screen.
g/ Assume 4 additional 2-lnch dia. monitoring wells (MWs) wiU be required in some areas where monitoring wells is not available and where nitrate
plume has crossed comp. boundary.
hi Assume electric submersible pumps with level controls. Assume pumps to operate continuously at 0.5 BHP and 70% efficiency.
II Instrumentation includes gauges and totalizer for flow recording.
jl Shallow trenching (2 ft deep) for recovery well piping and discharge piping (assumed to be a total of 60000 ft based on topography and aocessible areas)
No pavement removal or site clearing assumed along trenching locations. Use excavated soil for backfilling.
k/ Assume 10 separate pumping stations with equalization tanks and controls.
Probable Cost Estimates for GW Altematives.xls Page 2 of 3
Table 2·2
Opinion of Probable Costs to Install and Operate a Groundwater Extraction System along the Site Compliance Boundary
with Discharge to the NRWWTP (Alternative 1)
DESCRIPTION
Corrective Action Plan
Neuse River Wastewater Treatment Plant
Raleigh, North Carolina
NOTES UNITS QTY UNIT COST
($)
V Assumes installation of 6 boosternift stations between the extraction system and discharge to NRWWTP (effluent discharge).
These stations are assumed to include a small pre-fabricated fiberglass buidling, polyethylene tank w/pump and controls.
ml Assumes 12-inch diameter HOPE pipe to convey water to the treatment plant installed in trenches.
n/ Electrical hookup to extraction wells and control panels.
TOTAL COST
($)
o/ Assumes 35 weeks for installation. Includes labor and expenses for a full--time construction oversight and project management/coordination.
p/ Assumes three-day visits, twice a month plus 4 contingent visits by a qualified technician.
q/ Assumes 0 .5 hp/extraction pump, 10 transfer/effluent pumps and 6-10 hp pumps in the lift/booster stations operating at 75% efficiency and $0.1/kw-hr ul
r/ Assume sampling of 12 MWs + 1 O surface water locations three times a year. In addition 88 extraction wells will be sampled once a year.
Assume 4 days to sample by 2 technicians plus travel related expenses. The samples wm be analyzed for nitrates and field parameters.
4 days to sample by 2 technicians plus travel related expenses.
s/ Assumes in-place abandonment of recovery & monitor wells and discharge piping (no excavation/removal).
aa/ The NRWWTP will have to be expanded to handle treatment of extracted water. Assumes 2 gpm per well and calculated for gpd .
ab/ The extracted water will be treated at the NRWWTP along with the other wastewater. Assumes 2 gpm per well with continuous operation.
The rate used is $750/MG as provided by the City personnel.
ac/ Assume 1 o separate collection system with individual control panels to operate recovery wells In that system.
-The recovery system is assumed to be operated for approximately 30 years.
-Contingency used for each item varies and is based on information available at the time of preparing these costs and previous with similar projects .
-Costs are based on vendor information, contractors' estimate, cost estimation manuals, and past experience. Actual costs can vary depending
upon the final design and project/site conditions.
-Abbreviations: ea = each; Is = lump sum; hr= hours; CY= cubic yards; LF = linear feet; gal -gallons; wk = week; MG = Million Gallons
-Total Costs are rounded to nearest $10 and the present worth costs are rounded to nearest $100.
Probable Cost Estimates for GW Alternatives.xis Page3 of 3
Table 2-3
Opinion of Probable Costs to Install and Operate a Groundwater Extraction System in Field #50, #500, and #60
with Land Application or Discharge to the NRWWTP, and Long-term Monitoring in Other Areas {Alternative 2)
Corrective Action Plan
Neuse River Wastewater Treatment Plant
Raleigh, North Carolina
DESCRIPTION NOTES UNITS QTY UNIT COST TOTAL COST
($} ($}
I. Design Services
1. Project ManagemenVCoordination al Is $6,100 $6,100
2 . Engineering Design/Work Plan/Contract Documents Preparation/HASP b/ Is $30,000 $30,000
3 . Regulatory Negotiations/Meetings Is 1 $5,000 $5,000
4. Access Agreements/Negotiations cl Is 1 $20,000 $20,000
5. Pre-bid Meeting/Contractor Selection/Contracting Is 1 $5,000 $5,000
Subtotal Design Services Costs $66,100
6. Contingency (20% of Design Services Costs) Is 1 $13,200 $13,200
Total Design Services Costs $79,300
PW of Total Design Services Costs d/ $75,400
(Distribution in Year 1}
II. Construction and Startup Costs
1. Construction Costs
1. Mobilization/Demobilization/Setup Is $10,000 $10,000
2. Site Clearance/Temporary Road Construction et Is $30,370 $30,370
3. Installation of GW Extraction Wells in Field #50 (7 wells} fl ea 7 $6,800 $47,600
4. Installation of GW Extraction Wells in Field #500, #60 (33 wells} fl ea 33 $5,100 $168,300
5. Additional Groundwater Monitoring Wells Installation fl ea 4 $2,450 $9,800
6. IDW Disposal (drilling cuttings/non-hazardous} gt cy 87 $55 $4,790
7. Extraction Well vaults (abovegrade) and guardposts ea 40 $1,210 $48,400
8. Extraction Well pumps and Level Switches h/ ea 40 $2,320 $92,800
9. Well Head Fittings, and Valves, and Instrumentation i/ ea 40 $750 $30,000
10. Trenching (for groundwater recovery pipe installation} j/ If 21186 $3 $61,700
11. Backfilling trenches jl cy 3140 $2 $6,280
12. Groundwater Extraction piping k/ If 2540 $7 $17,780
13. GW Piping to NRWWTP II If 21186 $20 $423,720
14 . Equalization Tank (polyethylene} and Transfer Pump ml Is $4,400 $4,400
15. Lift-stations/Booster Stations rt Is 2 $23,000 $46,000
16. As-built survey Is 1 $15,000 $15,000
17. Electric hookup/Wiring/Power Drop pl Is $117,080 $117,080
18. Electrical Control Panel (groundwater extraction system) Is $40,000 $40,000
19. Site Cleanup/Restoration Is $7,500 $7,500
Subtotal Construction Costs $1,181,520
2. Engineering Services
1. Record Drawings/Construction ReporVO&M Manual Is $25,000 $25,000
2. Engineering Oversight {labor and expenses) qi Is $68,000 $68,000
3. System startup/shake down Is $20 ,000 $20,000
4 . Project ManagemenVCoordination al Is $11,300 $11 300
Subtotal Engineering Services Costs $124,300
3. Contingency (20% of Capital Costs} $261,160
Total Construction and Engineering Services Cost $1,566,980
PW of Construction and Engineering Services Cost d/ $1,417,900
(distribution in Yr.2}
Probable Cost Estimates for GW Alternatives.xis Page 1 of 3
Table 2-3
Opinion of Probable Costs to Install and Operate a Groundwater Extraction System in Field #50, #500, and #60
with Land Application or Discharge to the NRWWTP, and Long-term Monitoring in Other Areas (Alternative 2)
Corrective Action Plan
Neuse River Wastewater Treatment Plant
Raleigh, North Carolina
DESCRIPTION NOTES UNITS QTY UNIT COST TOTAL COST
($) ($)
Ill, Operation, Maintenance, and Monitoring (OMM) Costs
a. Annual O&M and Monitoring (30 years)
1. System O&M
a. Project Management/sub oversight al Is $11 ,200 $11,200
b. System O&M Labor/expenses ti ea 28 $1,350 $37,800
C. Electrical Power u/ kw-hr 435,489 $0.10 $43,550
d . Equipment Repair/Replacement Is 1 $5,000 $5,000
e. Data review/engineering support ea 12 2,140 $25,680
Subtotal Annual O&M Cost $123,230
2. Triennial Monitoring (12 MWs + 40 EWs + 10 surface water samples+ 6 QNQC samples)
a. Project Management/Coordination al Is $6,100 $6,100
b. Labor -sampling (triennial) vi ea 3 $5,000 $15,000
C. Analyticals : 12 MWs + 10 surface water samples+ 4 QNQC samples xi ea 78 $15 $1,170
d. Analyticals: 40 EW samples + 6 QNQC samples (annual) xi ea 46 $15 $690
e . Equipment rental (annual)/Reimbursable ea 3 · $1,000 $3,000
f. Monitoring report to Agency (triennial) Is 3 $10,000 $30,000
g . Regulatory Negotiations/Meetings Is $5,000 $5 000
Subtotal annual Monitoring Cost (annual) $61,000
3. Contingency (20% of Annual O&M and Monitoring Costs) $36 ,850
Total Annual OMM Cost $221,080
PW of Annual OMM for 30 Years di $3,187,300
(distribution in Yrs.2 thru' 31)
V. Decommissioning Costs
1. a. Project Management/Coordination al Is $13,900 $13,900
b. Abandon Extraction Pumps/discharge piping zl Is $20,000 $20,000
C. Abandon Extraction and Monitoring Wells zl If 4940 $8 $39,520
C. Labor/expenses Is $9,000 $9 ,000
d. Regulatory Negotiations/Meetings Is $5,000 $5,000
e. Closure Report Is $10,000 $10,000
Subtotal Decommissioning Costs $97,400
2. Contingency (20% of Annual Decommissioning Costs) $19,480
Total Decommissioning Costs $116,880
PW of Decommissioning Costs (Years 30) di $23,600
(distribution in Yr. 32)
PW OF TOTAL PROBABLE COSTS di $4,704,200
Notes/Key Assumpstions·
al Project management and coordinating all project related activitities.
bl Detailed design of the remediation system for equipment selection and construction including possible small scale treatability study for ion exchange.
cl Access agreement for piping installation; Existing NPDES permit may have to be modified or new NPDES permit may be required for discharge of
treated water into Neuse River.
di Present worth costs were estimated based on a net annual discount rate of 5.125%, assuming year-end distribution.
el Assume 4-acre of tree/shrub clearance for piping/well installation and 1000 feet of gravel road for access to drill rig.
fl Based on groundwater modeling, 40 Extraction Wells (EW) is assumed to be required in Fields 50, 500, and 60. Wells will be constructed
of 6-in dia PVC casing and screen. The depth of wells in Field 50 will be approx. 80 ft with 20-ft screen and depth of wells in Fields 500 and 60 will
be approx. 60 ft with 20-ft screen. In addition four 2-inch diameter MWs will be installed in select areas for long-term monitoring.
gl Assume that the waste material is non-hazardous .
h/ Assume electric submersible pumps with level controls. Assume pumps to operate continuously at 0.5 BHP and 70% efficiency.
i/ Instrumentation includes gauges and totalizer for flow recording.
j/ Shallow trenching (2 ft deep) for recovery well piping and collection piping all the way to the digesters (assumed to be a total of 21186 ft based
on topography and accessible areas. No pavement removal or site clearing assumed along trenching locations . Use excavated soil for backfilling.
Probable Cost Estimates for GW Alternatives.xis Page 2 of 3
Table 2-3
Opinion of Probable Costs to Install and Operate a Groundwater Extraction System in Field #50, #500, and #60
with Land Application or Discharge to the NRWWTP, and Long-term Monitoring in Other Areas (Alternative 2)
Corrective Action Plan
Neuse River Wastewater Treatment Plant
Raleigh, North Carolina
DESCRIPTION NOTES UNITS QTY UNIT COST
($)
TOTAL COST
($)
k/ Assumes 2" dia . PVC/HOPE piping for extracting groundwater to a treatment system.
I/ Groundwater piping to the NRWWTP (assumes 4-inch dia. PVC pipe). Assumes heating tape for insulating recovery piping and effluent piping.
m/ Assume 1000-gal equalization tank + 5hp transfer pump to pump to the NRWWTP (discharge).
p/ Electrical hookup to extraction wells and control panel.
q/ Assumes 15 weeks for installation. Includes labor and expenses for a full-time construction oversight and project management/coordination.
r/ Assumes installation of 2 booster/lift stations between the extraction system and discharge to Neuse River Treatment Plant (effluent discharge).
These stations are assumed to include a small pre-fabricated fiberglass buidling, polyethylene tank w/pump and controls.
U Assumes two-day visits, twice a month plus 4 contingent visits by a qualified technician.
u/ Assumes 0.5 hp/extraction pump, 3 -10 hp pumps in the lift stations operating at 70% efficiency and $0.1/kw-hr utility cost.
vi Assumes 3 days for sampling of 12 monitoring wells and 44 extraction wells and system sampling triennially for the life of the project plus travel-related
xi Analysis of 12 GW samples + 1 O surface water samples + 4 QA/QC samples/event triennially for nitrate. Analysis of 42 EW samples annually for nitrate
These costs do not include sampling compliance (test) wells required under the biosolids permit.
'll Assumes in-place abandonment of recovery & monitor wells and discharge piping (no excavation/removal).
during crop growing season. Assume 2 gpm per well with continuous operation
-The recovery system is assumed to be operated for approximately 30 years.
-Contingency used for each item varies and is based on information available at the time of preparing these costs and previous with similar projects.
-Costs are based on vendor information, contractors' estimate, cost estimation manuals, and past experience. Actual costs can vary depending
upon the final design and project/site conditions.
-Abbreviations: ea = each; Is = lump sum; hr= hours; CY= cubic yards; LF = linear feet; gal -gallons; wk = week; MG = million gallons
-Total Costs are rounded to nearest $10 and the present worth costs are rounded to nearest $100.
Probable Cost Estimates for GW Alternatives.xis Page 3 of3
Table 2-4
Opinion of Probable Costs to Install and Operate a Groundwater Extraction System In Fields #50, #500, and #60
with On-site Treatment and Discharge, and Long-term Monitoring in other Areas (Alternative 3)
Corrective Action Plan
Neuse River Wastewater Treatment Plant
Raleigh, North Carollna
DESCRIPTION NOTES UNITS QTY UNIT COST TOTAL COST
($) ($)
I. Detailed Design Services
1. Project Management/Coordination a/ Is $6,500 $6,500
2. Engineering Design/Work Plan/Contract Docments Preparation/HASP b/ Is $30,000 $30,000
3. Regulatory Negotiations/Meetings Is 1 $5,000 $5,000
4. Access Agreements/Negotiations/Permitting cl Is 1 $20,000 $20,000
5. Pre-bid Meeting/Contractor Selection/Contracting Is 1 $3,500 $3,500
Subtotal Design Services Costs $65,000
6. Contingency (20% of Design Services Costs) Is $13,000 $13,000
Total Design Services Costs $78,000
PW of Total Design Services Costs d/ $74,200
(Distribution in Year 1) $2
II. Construction and Startup Costs
1. Construction Costs
a. Mobilization/Demobilization/Setup Is $10,000 $10,000
b. Site Clearance/Temporary Road Construction e/ Is 1 $26,800 $26,800
c. instalation of GW Extraction Wells in Field #50 (7 wells) fl aa 7 $6,800 $47,600
d. Installation of GW Extraction Wells in Field #500, #60 (33 wells) fl ea 33 $5,100 $168,300
e. Additional Groundwater Monitoring Wells Installation g/ ea 4 $2,450 $9,800
f. IOW Disposal (drilling cuttings/non-hazardous) cy 87 $55 $4,790
g. Extraction Well vaults (abovegrade) and guardposts ea 40 $1,210 $48,400
h. Extraction Well pumps and Level Switches h/ ea 40 $2,320 $92,800
i. Well Head Fittings, and Valves, and Instrumentation j/ ea 40 $750 $30,000
j. Trenching (for groundwater recovery pipe installation} j/ If 5400 $3 $15,730
k. Backfilling trenches j/ cy BOO $2 $1,600
Groundwater Extraction piping k/ If 2540 $7 $17,780
m. GW Recovery pipe and Effluent piping installation V If 4800 $20 $96,000
n. Equailization Tank (polyethylene) and Transfer Pump ml Is $4,400 $4,400
0 . Ion Exchange System (includes green sand filter for iron removal) nl Is $90,000 $90,000
p . Spent Regenerant Storage Tank aa/ Is $40,000 $40,000
q. Expansion of NRWWTP ab/ gal 3000 $3.5 $10,500
r. As-built survey Is 1 $20,000 $20,000
s. Lift-stations/Booster Stations r/ ea 2 $23,000 $46,000
t. Site Cleanup/Restoration Is $5,000 $5,000
u. Buildings w/HVAC, Lighting and treatment system plumbing of ea $50,000 $50,000
V. Electrical hookup/wiring p/ Is $112,080 $112,080
w. Electrical Control Panel (groundwater extraction/discharge system) Is $50,000 $50,000
Subtotal Construction Costs $997,580
2. Engineering Services
a. Record Drawings/Construction Report/O&M Manual Is $20,000 $20,000
b. Engineering Oversight (labor and expenses) q/ Is $47,000 $47,000
C. System startup/shake down Is $20,000 $20,000
d. Project Management/Coordination a/ Is $8,700 $8,700
Subtotal Engineering Services Costs $95,700
3. Contingency (20% of Capital Costs) $218,660
Total Construction and Engineering Services Cost $1,311,940
PW of Construction and Engineering Services Cost di $1,187,100
(distribution in Yr.2)
Ill. Operation, Maintenance, and Monitoring (OMM) Costs
a. Annual O&M and Monitoring (30 years)
1. System O&M
a. Project Management/sub oversight a/ Is $12,900 $12,900
b. System O&M Labor/expenses s/ ea 28 $1,050 $29,400
C. Electrical Power ti kw-hr 217,744 $0.10 $21,770
d. Regenerant for Ion Exchange System u/ ea 365 $150 $54,750
e. Neutralization, denitrification and disposal of regenerant ac/ MG 0.55 $750 $410
f . Equipment Repair/Replacement Is $2,500 $2,500
g. Data review/engineering support ea 12 1,340 $16,080
h. Quarterly Reporting for NPDES Permit ea 4 $1,000 $4,000
Probable Cost Estimates for GW Alternatives.xis Page 1 of3
Table2-4
Opinion of Probable Costs to Install and Operate a Groundwater Extraction System in Fields #50, #500, and #60
with On-site Treatment and Discharge, and Long-term Monitoring in Other Areas (Alternative 3)
Corrective Action Plan
Neuse River Wastewater Treatment Plant
Raleigh, North Carolina
DESCRIPTION NOTES UNITS QTY UNIT COST TOTAL COST
($) ($)
2 . Triennial Groundwater and Surfacewater Monitoring
a . Project Management/Coordination al ls $5,300 $5,300
b. Labor -sampling vi ea 3 $5,000 $15,000
C. Analyticals: 12 MW+ 10 surface water samples+ 4 QNQC samples w/ ea 78 $15 $1,170
d . Analyticals: 40 EW samples + 6 QNQC samples (annual) w/ ea 46 $15 $690
e . Analyticals: Monthly treatment effluent xJ ea 12 $15 $180
f . Effluent Toxicity Testing/NP DES Sampling (quarterly) y/ ea 4 $350 $1,400
g . Equipment rental (triennial)/Reimbursable ea 3 $1,000 $3,000
h. Monitoring report to Agency (triennial) Is 3 $10,000 $30,000
i. Regulatory Negotiations/Meetings Is $2,500 $2,500
Subtotal annual Monitoring Cost (annual) $59,000
3. Contingency (20% of Annual O&M and Monitoring Costs) $40,160
Total Annual OMM Cost $240,970
PW of O&M and Monitoring (30years) di $3,474,100
V. Decommi&&ioning Costs
1. a . Project Management/Coordination a/ Is $13,900 $13,900
b. Abandon Extraction Pumps/discharge piping zJ Is $20,000 $20,000
C. Abandon Extraction and Monitoring Wells z/ If 4940 $8 $39,520
d . Labor/expenses Is 1 $9 ,000 $9,000
e . Regulatory Negotiations/Meetings Is $5,000 $5,000
f. Closure Report Is $10,000 $10,000
Subtotal Decommissioning Costs $97,400
2. Contingency (20% of Annual Decommissioning Costs) $19,480
Total Decommissioning Costs $116,BB0
PW of Decommissioning Costs (Years 30) d/ $23,600
(distribution in Yr. 32)
PW OF TOTAL PROBABLE COSTS d/ $4,759,000
Notes/Key Assum pstions:
a/ Project management and coordinating all project related activitities.
bl Detailed design of the remediation system for equipment selection and construction including possible small scale treatability study for ion exchange.
c/ Access agreement for piping installation; Existing NPDES permit may have to be modified or new NPDES permit may be required for discharge of
treated water into Neuse River.
d/ Present worth costs were estimated based on a net annual discount rate of 5.125%, assuming year-end distribution.
e/ Assume 1 acre of tree/shrub clearance for piping/well installation and 1000 feet of gravel road for access to drill rig .
f/ Based on groundwater modeling, 40 Extraction Weis (EWs) is assumed to be required in fields 50, 500, and 60. Wells will be constructed
of 6-in dia PVC casing and screen. The depth of wells in Field 50 will be approx. 80 ft with 20-ft screen and depth of wells in Fields 500 and 60 will
be approx. 60 ft with 20-ft screen .
g/ Assume 4 additional 2-inch dia. monitoring wells (MWs) will be required in some areas where monitoring wells is not available and where nitrate
plume has crossed comp. boundary.
h/ Assume electric submersible pumps with level controls. Assume pumps to operate continuously at 0.5 BHP and 70% efficiency.
i/ Instrumentation includes gauges and totalizer for flow recording.
j/ Shanow trenching (2 ft deep) for recovery well piping and discharge piping (assumed to be a total of 5400 ft based on topography and accessible areas)
No pavement removal or site clearing assumed along trenching locations. Use excavated soil for backfilling.
k/ Assumes 2" dia. PVC/HOPE piping for extracting groundwater to a treatment system.
V Effluent piping to Neuse River or Beddingfield Creek (assumes 4-inch dia. PVC pipe). Assumes to be underground (2 ft deep).
m/ Assume 1000-gal equalization tank+ 5hp transfer pump to pump through ion-exchange to the river (discharge).
n/ Assumes that green sand filter would be required to treat iron/manganese in the extracted GW prior to treating for nitrates. Ion exchange system
for treatment of nitrate is assumed lo be leased and therefore no capital costs included.
o/ Wiring to extraction wells along with the control wiring including a power drop.
pf Electrical hookup to extraction wells, treatment system and treatment building including power drop.
q/ Assumes 1 o weeks for installation. Includes labor and expenses for a full-time construction oversight and project management/coordination.
s/ Assumes one-day visits, twice a month plus 4 contingent visits by a qualified technician.
ti Assumes 0.5 hp/extraction pump, 5hp transfer pump operating at 70% efficiency and $0.1/kw-hr utility cost.
u/ Assumes regeration ot ion exchange every day with an approximate volume of 2500 gallons of regenerant.
v/ Assumes 3 days for sampling of 12 monitoring wells and system sampling triennially for the rite of the project plus travel-related expenses.
w/ Analysis of 12 GW samples + 10 surface water samples+ 4 QNQC samples/event triennialfty for nitrate. Analysis of 42 EW samples annualy for nitrate
These costs don't include costs for sampling compliance (test) wells required under the biosofids permit.
Probable Cost Estimates for GW Alternatives.xis Paga2 of3
Table 2-4
Opinion of Probable Costs to Install and Operate a Groundwater Extraction System in Fields #SO, #500, and #60
with On-site Treatment and Discharge, and Long-tenn Monitoring in other Areas (Alternative 3)
Corrective Action Plan
Neuse River Wastewater Treatment Plant
Raleigh, North Carolina
DESCRIPTION NOTES UNITS QTY UNIT COST
($)
TOTAL COST
($)
xi Monthly effluent analysis for nitrates.
y/ Quater1y bioassays required by the NPDES permit for the groundwater remediaton system.
z/ Assumes in-place abandonment of recovery & monitor wells and discharge piping (no excavation/removal).
aa/ Assumes 2-6000gal fiberglass tanks on foundation for storage of regenerant. Also assumes that regenerant will be neutralized at NRWWTP
ab/ Upgrading NRWWTP to handle around 3000 gal of spent regenerant every other day (neutralization and denitrification).
ac/ Assumes neutralization of regenerant solution and hauling it to the NRWWTP for denitrifcation and disposal once every 2 days.
Treatment Plant and disposes the nitrate concentrated regenerant at their treatment plant.
-The recovery system is assumed to be operated for approximately 30 years.
-Contingency used for each item varies and is based on information available at the time of preparing these costs and previous with similar projects.
-Costs are based on vendor information, contractors' estimate, cost estimation manuals, and past experience. Actual costs can vary depending
upon the final design and project/site conditions.
-Abbreviations: ea = each; Is= lump sum; hr= hours; CY= cubic yards; LF = linear feet; Gal -gallons; wk= week;
-Total Costs are rounded to nearest $10 and the present worth costs are rounded to nearest $100.
Probable Cost Estimates for GW Alternatives.xis Page 3 of 3
Table 2-5
Opinion of Probable Costs for Enhanced Denitriflcation (EON) in Fields #50, #500, #60 and Long-term Monitoring in Other Areas
(Alternative 4)
Corrective Action Plan
Neuse River Wastewater Treatment Plant
Raleigh, North Carolina
DESCRIPTION NOTES UNITS QTY
I. Design Services
1. Project ManagemenUCoordination a/
2. Pilot Test of Enhanced Denitrification b/
3. Engineering DesignMlork Plan/Contract Docments Preparation/HASP cl
4. Regulatory Negotiations/Meetings
5 . Access Agreements/Negotiations/Permitting el
6 . Pre-bid Meeting/Contractor Selection/Contracting
Subtotal Design Services Costs
6. Contingency (20% of Design Services Costs)
Total Design Services Costs
PW of Total Design Costs d/
(distribution in year 1)
II. Construction and Startup Costs
1. Construction Costs
1 Mobilization/Demobilization
2 Site Clearance/Temporary Road Construction
3 Injection well installation
4 Injection System (portable mixing tank/storage/pumps/piping)
5 Additional Groundwater Monitoring Wells Installation
6 IDW disposal
Subtotal Construction Costs
2. Engineering Services
1 . Record Drawings/Construction· Report/O&M Manual
2 . Engineering Oversight (labor and expenses)
3. Project ManagemenUCoordination
Subtotal Engineering Services Costs
3. Contingency (20% of Construction and Engineering Costs)
Total Construction and Engineering Services Costs
fl
g/
hi
i/
j/
PW of Total Construction and Engineering Services Costs d/
(distribution in year 2)
Ill. Operation, Maintenance, and Monitoring (OMM) Costs
a. O&M and Monitoring (Year 1)
1. O&M -Enhanced Denitrication (biweekly/monthly)
a . Project ManagemenUsub oversighUtroubleshooting
b. Carbon Source (assumes com syrup for pricing purposes)
c. Potable Water (for making reagent solution)
d . O&M labor
e. Piping/Fittings/Mixing Tank/Pump Repair/Replacement
f . Truck Rental
g. Project Expenses (gasoline/per diem)
h. Engineering Support/Data Review
al
k/
k/
I/
Is
Is
Is
Is
Is
Is
Is
Is
ea
Is
ea
ea
Is
Is
Is
1
1
1
1
1
1
1
1
195
1
10
230
Is 1
gal 37,050
gal 333,450
hr 1870
Is 1
ea 19
Is 19
ea 12
2. Triennial Monitoring (20 MWs + 20 lnj. wells+ 10 surface water samples+ 6 QA/QC samples)
a. Project ManagemenUCoordination a/ Is 1
b. Labor -sampling ml ea 3
c. Analytical: 50 samples plus 6 QA/QC samples n/ ea 168
d. Analytical: Biogeochemical Parameters (20 samples -annual) of ea 20
f. Equipment rental/expenses (triennial) p/ ea 3
g. Monitoring report to Agency (triennial) Is 3
Subtotal Annual O&M and Monitoring Cost (Year 1)
3. Contingency (20% of Annual O&M and Monitoring Costs)
Total Annual O&M and Monitoring Cost (Year 1)
PW of Annual O&M and Monitoring (Year 1 O&M) d/
Probable Cost Estimates for GW Alternatives.xis
UNIT COST
($)
$5,800
$80,000
$25,000
$5,000
$20,000
$2,000
$5,000
$26,800
$2,800
$45,000
$2,450
$55
$25,000
$39,000
$6,400
$14,800
$2.50
$0.010
$40
$1,500
$300
$300
$3,540
$9,900
$15,000
$15
$350
$1,500
$10,000
TOTAL COST
($)
$5,800
$80,000
$25,000
$5,000
$20,000
$2,000
$137,800
$27,600
$165,400
$149,700
$5,000
$26,800
$546,000
$45,000
$24,500
$12,650
$660,000
$25,000
$39,000
$6,400
$70,400
$146,080
$876,480
$793,100
$14,800
$92,625
$3,300
$74,800
$1,500
$5,700
$5,700
$42,480
$9,900
$45,000
$2,520
$7,000
$4,500
$30,000
$339,800
$68,000
$407,800
$369,000
1 of 3
Table 2-5
Opinion of Probable Costs for Enhanced Denitrification (EON) in Fields #50, #500, #60 and Long-term Monitoring in Other Areas
(Alternative 4)
Corrective Action Plan
Neuse River Wastewater Treatment Plant
Raleigh, North Carolina
DESCRIPTION
Pa ment Year 2
Years 2 - 5 O&M and Monitoring
1. O&M -Enhanced Denitrification (monthly)
a. Project Management/sub oversight/troubleshooting
b . Carbon Source (assumes com syrup for pricing purposes)
c. Potable Water
d. O&M labor
e . Piping/Fittings/Mixing Tank/Pump Repair/Replacement
f . Truck Rental
g. Project Expenses (gasoline/per diem)
h. Engineering Support/Data Review
NOTES UNITS
al
k/
kl
II
Is
gal
gal
hr
Is
ea
Is
ea
QTY
23 ,400
210,600
1180
1
12
12
4
2 . Triennial Monitoring (20 MWs + 20 inj. wells+ 10 surface water samples+ 6 QNQC samples)
a. Project Management/Coordination a/ Is 1
b. Labor -sampling (triennial) p/ ea 3
c. Analytical: 50 samples plus 6 QNQC samples n/ ea 168
d. Analytical: Biogeochemical Parameters (20 samples -annual) o/ ea 20
f . Equipment rental/expenses (triennial) r/ ea 3
g. Monitoring report to Agency (triennial) Is 3
Subtotal Annual O&M and Monitoring Cost
3. Contingency (20% of Annual O&M and Monitoring Costs)
Total Annual O&M and Monitoring Cost
PW of Annual O&M and Monitoring (Year 2-5)
Payment Years 3 -6
Year 6-30 O&M and Monitoring
1. O&M -ERD (semi-annual)
a. Project Management/sub oversight/troubleshooting
b. Carbon Source (assumes com syrup for pricing purposes)
c. Potable Water
d. O&M labor
e . Piping/Fittings/Mixing Tank/Pump Repair/Replacement
f. Truck Rental
g. Project Expenses (gasoline/per diem)
h. Engineering Support/Data Review
2. Triennial Groundwater and Surfacewater Monitoring
a. Project Management/Coordination
b. Labor -sampling (triennial)
c. Analytical: 50 samples plus 6 QNQC samples
d . Analytical : Biogeochemical Parameters (20 samples -annual)
f. Equipment rental/expenses
g. Monitoring report to Agency
Subtotal Annual O&M and Monitoring Cost
10 . Contingency (20% of Annual O&M and Monitoring Costs)
Total Annual O&Mand Monitoring Cost
di
al
kl
kl
II
al
ml
nJ
ol
PW of Annual O&M and Monitoring (Year 6-30) di
Payment Years 7-31
Probable Cost Estimates for GW Alternatives .xis
Is 1
gal 7,800
gal 35,100
hr 200
Is 1
ea 2
Is 2
ea 2
Is 1
ea 3
ea 168
ea 20
ea 3
Is 3
UNIT COST
($)
$14,900
$2 .00
$0.010
$40
$1,500
$300
$300
$7,350
$9,900
$15,000
$15
$350
$1,500
$10,000
$4,900
$2.00
$0 .010
$40
$1,500
$300
$300
$8,700
$7,200
$7,000
$15
$350
. $1,500
$10,000
TOTAL COST
($)
$14,900
$46,800
$2,100
$47,200
$1,500
$3,600
$3 ,600
$29,400
$9,900
$45,000
$2 ,520
$7,000
$4,500
$30,000
$248,000
$49,600
$297,600
$952,100
$4,900
$15,600
$400
$8,000
$1,500
$600
$600
$17,400
$7,200
$21,000
$2 ,520
$7,000
$4,500
$30,000
$121,200
$24,200
$145,400
$1,499,500
2 of 3
Table 2-5
Opinion of Probable Costs for Enhanced Denltriflcatlon (EON) in Fields #50, #500, #60 and Long-term Monitoring in Other Areas
(Alternative 4)
Corrective Action Plan
Neuse River Wastewater Treatment Plant
Raleigh, North Carolina
DESCRIPTION NOTES UNITS QTY UNIT COST
($)
TOTAL COST
($)
IV. Decommissioning Costs
1. a. Project Management/Coordination
b. Abandon Extraction and Monitoring Wells
c. Labor/expenses
d. Regulatory Negotiations/Meetings
e. Closure Report
Subtotal Closure Costs
2. Contingency (20% of Annual Monitoring Costs)
Total Annual Monitoring Costs
a/
r/
PW of Decommissioning Costs (Years 30) di
{distribution in Yr. 32)
PW OF TOTAL PROBABLE COSTS di
Notes/Key Assum pstions:
a/ Project management and coordinating all project related activities.
b/ Assumes 6 months pilot test. These wells will be used for full-scale application ;
Is
If
Is
Is
Is
d Detailed design of the remediation system for equipment selection and HASP preparation .
1
17775
1
1
1
$21,900
$6
$4,720
$5,000
$15,000
di Present worth costs were estimated based on a net annual discount rate of 5.125%, assuming year-end distribution.
el Access agreement for well installation and injection permitting.
fl Assume 1 acre of tree/shrub clearance for piping/well installation a·nd 1000 feet of gravel road for access to drill rig .
$21,900
$106,650
$4,720
$5,000
$15,000
$153,300
$30,660
$183,960
$37,200
$3,800,600
gl Assumes installation of 195 2" PVC wells to a depth of 80 ft in Field 50, 500 and 60. This is assuming a 25 ft between wells would
be required to establish reactive {denitrification) zones . Actual well locations and spacing will be based on a pilot test.
h/ Includes 6000-gallons syrup storage tank, a mixing tank/trailler, pumps, and misc. piping/equipment.
ii Assume 10 additional 2-inch dia . monitoring wells (MWs) will be required in some areas where monitoring wells is not available and
where nitrate plume has crossed comp. boundary and to monitor denitrification performance.
jl Assumes 8 weeks for installation. Includes labor and expenses for a full-time construction oversight and project management/coordinatio
k/ Assume injection of 100 gallons of 10% solution per well per event; biweekly first 6 months, monthly from 6 months to 5 years; and
semiannually thereafter. Water is assumed to be available locally.
II Assumes 0.6 hr for mixing and injection of approximately 100 gallons of electron donor solution per injection event per well .
m/ Assumes 8 days of sampling by 2 technicians collecting nitrate and other geochemical data .
n/ Analysis of 40 groundwater samples + 10 surfacewater samples + 6 QA/QC samples/event for nitrate. These costs
do not include sampling compliance (test) wells required under the biosolids permit.
ol Limited biogeochemical analysis : electron acceptors, TOC, BOD, COD, altkalinity, metabolic acids and dissolved gases.
pl Assumes in-place abandonment of injection & monitor wells.
-Costs are based on vendor information, contractors' estimate, cost estimation manuals, and past experience .
-Abbreviations: ea = each; Is= lump sum; hr= hours; CY= cubic yards; LF = linear feet; gal -gallons; MG= million gallons; wk= week;
Probable Cost Estimates for GW Alternatives.xis 3 of 3
Analytical Requlrememta
Table 3-1
Proposed Performance Monitoring Requirements
Corrective Action Plan
Neuse River Wastewater Treatment Plant
Raleigh, North Carolina.
Eatrmafed Y,earlv Schedole ol Pull-S"tale Ooe_ration~
Mcli1m 'M !illllh M.o.nth ~OAlh Month Mentn Mo nth Month Month Mon\h-Month SampHng Parameter Analytfcal Mefttod 1 2 ~ 4 5 6 7 8 ~ 10 11 tv,onth 12
Field Parameters
Dissolved Oxygen Horiba U-22 X X
Redox Horiba U-22 X X
pH Horiba U-22 X X
Temperature Horiba U-22 X X
Specific Conductance Horiba U-22 X X
Anal :i!ical Parameters
Nitrate USEPA 353 .2/300.0 X X
NOTES:
USEPA United States Environmental Protection Agency
SM Standard Methods
• = The yearly schedule is based on triennial sampling events and may be revised based on performance of the groundwater extraction system.
Proposed monitoring wells for performance monitoring include MW-105, MW-108, MW-109, MW-110, MW-111 , MW-1110, MW-112 and proposed
!additional MWs in selected fields included in variance request.
X
X
X
X
X
X
Analysis' of Groundwater Capture by Proposed Remedial
Wellfields
City of Raleigh Biosolids Application Fields
January 25, 2005
Eric G. Lappala, P .E.
Advocacy ,.Sound Science--lnncvation · .. Solutions
4005 Lake Springs Court
Raleigh, NC 27613
Contents
1 Introduction ................................................................................................................. 3
1.1 Purpose and Objective ........................................................................................ 3
1.2 Approach ............................................................................................................. 3
1.3 Disclaimer ........................................................................................................... 3
2 Pumping Rate Estimation ........................................................................................... 4
3 Updated Groundwater Transport Model.. ................................................................... 6
4 Capture Analysis ......................................................................................................... 8
List of Figures
Figure 1.--Drawdown vs Pumping Rate .................................................................. '. ......... 5
Figure 2.--Water level calibration check of updated model. ............................................. 7
Figure 3.--Captured pathlines from fields 50, 60, and 500 .............................................. 10
List of Tables
Table 1.--Location, depth, open intervals, and yield of simulated groundwater
interception wells ................................................................................................................ 9
11
1 Introduction
This report documents the results of groundwater interception and capture analyses for
potential remedial groundwater migration control systems for areas where offsite
historical migration of nitrate has likely occurred from the City of Raleigh biosolids
application fields. These fields have historically been used by the City of Raleigh Public
Utilities Department (CORPUD) to dispose ofbiosolids from the Neuse River
Wastewater Treatment Plant (NRWWTP). This study was performed by Eagle
Resources P.A. under subcontract to ENSR Consulting and Engineering Inc (ENSR).
1. 1 Purpose and Objective
The purpose of this study was to assess the likely number, spacing, and steady state
pumping rate for groundwater interception wells necessary to preveI!-t future migration of
nitrate in groundwater across CORPUD property lines where such migration has likely
occurred historically.
The objective was to provide ENSR conceptual design information for their evaluation of
potential remedial alternatives as part of the Corrective Action Plan (CAP) for the
NEWWTP.
1.2 Approach
The general approach used to meet the objectives of this study comprised the following
• Update and refine of the groundwater flow model developed as part of the
Comprehensive Site Assessment (CSA) (ENSR, 2003) and the Supplemental Site
Assessment (SSA) (ENSR, 2004) to provide better spatial resolution in the areas
where groundwater capture was to be evaluated.
• Use the updated model to determine the likely spacing and yield for wells
necessary to capture all groundwater containing nitrates in excess of 2L standards
that has historically migrated, or is likely to migrate onto adjacent properties that
lie between CORPUD property and the Neuse River or its major tributaries.
1.3 Disclaimer
The work described herein was authorized by ENSR Purchase Order 2011435 dated April
16, 2003 to which was attached the agreed to scope of services for the work. All analyses
contained in this report relied upon data and information provided by others. Eagle
Resources P.A. makes no representations regarding the completeness, accuracy and
reliability of that data and information.
3
2 Pumping Rate Estimation
The groundwater flow model used for this study (MODFLOW) computes the head in the
33 ft x 33 ft square grid cell in which the well is located, it does not extrapolate the head
to the radius of the well screen or gravel pack. Consequently the maximum sustainable
pumping rate, Q that would not produce drawdown, s greater than the depth of the well
screen was estimated using solutions to the Theis equation for a confined aquifer:
Where: s = drawdown at distance, rand time, t ;
W(u) = The Theis Well function;
r 2 S u=-·
4Tt'
S= Storage Coefficient, L 0;
T= Transrnissivity of the aquifer, L 2/T = K*b
K = Hydraulic conductivity, LIT; and
b = Thickness of aquifer.
(1)
This equation was used to approximate the steady state drawdown because solutions for
drawdown in an unconfined aquifer approach the Theis solution for long pumping times
with S equal to the specific yield of the aquifer. A pumping time of 10,000 days was
used for the analysis .
The value of Tin equation 1 was taken as the sum of layers 2 and 3 from the CSA
groundwater flow model:
Where K; = hydraulic conductivity of layer i; and
b; = thickness of layer i.
To be conservative in well yield design a value of T of 10 ft/day was also evaluated.
Figure 1 shows the drawdown vs distance solution to equation 1 for pumping rates of 1.5,
2, and 3 gallons per minute. From this analysis extraction well pumping rates to achieve
capture cannot likely exceed 3 gallons per minute without causing drawdown that may be
in excess of well depths.
4
4 Capture Analysis
The updated groundwater flow model was used to assess the likely spacing and minimum
steady state pumping rates necessary to capture groundwater flow in five areas. These
areas are those where nitrates have likely moved on to property not owned or controlled
by CORPUD before being discharged to the Neuse River or its major Beddingfield
Creek. The five areas are downgradient of fields 50, 60, and 500.
Capture of groundwater migrating from these fields was simulated by placing particles in
lines across each field, or in some cases by placing a particle in the center of every model
cell where a field was located. Particles were placed in all layers. Pathlines traced out by
each particle were then computed using the U.S. Geological Survey MODPATH code.
MODPATH computes pathlines based upon the hydraulic head distribution that is
determined with the U.S. Geological Survey MODFLOW code used for the CSA and
SSA. All model components were run with the commercial modeling shell, Visual
MODFLOWTM.
Capture analyses runs with the updated model were made using extraction well spacing
of 100 and 200 feet, and pumping rates ranging from 1.5 to 3 gallons per minute each.
Adequate capture was achieved using a well spacing of generally 100 ft and pumping
rates of 2 to 3 gallons per minute. The close well spacing and low pumping rates are
required to achieve adequate capture and to keep all pathways on CORPUD property.
Table 1 shows the simulated depth, screened interval and pumping rates for each of the
extraction wells. The capture analysis results are shown on Figures 2 and 3.
The depths shown in Table 1 are based upon the layer depths and thicknesses in
conceptual and numerical groundwater flow model. The pumping rates were determined
to be he lowest amount to achieve adequate capture so as to minimize the amount of
water that the remedial program will have to dispose of. The design depths and pumping
rates should be based upon field-specific well logs and pumping tests.
8
Project Number:
Project Name:
Calculation By:
Subject:
Checked By:
Assum ptions:
Desi g n Calculations:
10724-003-300
Corrective Action Plan
Nanjun V. Shetty and Amol Keskar
Recovery Well Pumping System
Nanjun V. Shetty
Page2 of 2
Date: 02/08/05
Date: 02/08/05
Once the pipe size is determined then the total head at the pump outlet can
be determined from the Bernoulli equation. The pump can then be
specified from tables or pump design curves.
• The fluid being pumped is incompressible.
• Kinetic losses due to changes in velocity are negligible.
The design calculations were based on the following design criteria:
• The flow rate from each extraction well is assumed to be 2 gallons
per minute (2 gpm).
• The depth of extraction well farthest from the central collection
pipe is estimated to be 60 feet below surface grade (ft bsg).
• The friction losses were calculated using the proposed
conceptual layout of the collection piping system (as depicted in
Figure 2-2).
• Parallel pipe flow was assumed for pipes between extraction wells
and the main collection pipe.
• The change in elevation in the piping system was approximately
estimated using the Site topographic map and the proposed
layout of the piping system.
The pipe sizing and friction loss calculations were done using the unit
friction loss data as provided in the book, Cameron Hydraulic Data, Edited
by C. C. Heald. The attached spreadsheet shows the preliminary
calculations for the friction losses for various sections of the piping and the
total design head. The pump was specified for the total design head using
pump design curve and/or table or some similar information supplied by the
pump manufacturer.
I PRIVATE WELLS SAMPLED IN VICINITY OF NRWWTP ON DATES NOTED TO RIGHT
2
3
4
5
6
7
8
9
10
OWNER'S NAME
Adams, Dalton
Adams, Diane
Adams, Jimm y
Adams, Shirley
Baucom Julian I Clifton
Baucom William
Belvin Dann v
Blowe, Bobby
Brown, Svbil
Carroll, Kath y
1 Clark, John
12 Ross, Clee
3 Cowin o, Betty
,4 Daniels, Earl
15 Debnam Catherine
16 Debnam Clarence
1 7 Debnam. Judson &Shirley
1 8 Debnam, Renella
9 Debnam Retha 1
2
2
o Dunstan Ollie
1 Frison, Brenda
2 2 Hash, David
3 Ho okins, John
4 Howen, Kenny
2
2
2 s Hunter. Teri ·
6 McKinnon, Charles 2
2 7 Moore , Lu cv
2 8 Perkins Marvin
2 9 Rhodes William
Home#
772-6706
772-2348
772-6376
772-5956
772-1647
772-2242
772-7898
779-1399
773-2467
779-0683
662-5504
772-0428
772-1226
266-3581
266-3616
266-1923
266-1708
266-2387
266-4548
266-1829
773-1171
772-7049
772-0739
661-5785
553-5667
266-3073
553-5936
771-0714
553-7008
Draft Table 1-1 • Water Supply Wells.xi s
Work# Address
8401 Old Baucom Road
787-0125 8513 Old Baucom Road
8428 Old Baucom Road
8404 Old Baucom Road
3021 I 3005 Hickorv Tree Pl
-8004 7920 Old Baucom Road
6208 Mia/ Plantation Rd
2853 Shotwell Rd
8529 Old Baucom Road
8500 Old Baucom Road
8416 Old Baucom Road
2823 Shotwell Rd
8100 Old Baucom Road
5716 Mial Plantation Rd
5717 Mia! Plantation Rd
5525 Mia! Plantation Rd
5700 Mia/ Plantation Rd
5616 I 5620 Mial Plant Rd
5600 Mial Plantation Rd
5520 Mia/ Plantation Rd
546-4197 8549 Old Baucom Road
6216 Mial Plantation Rd
8321 Old Baucom Road
773-7184 2820 Brown Field
1340 Pine trail
5708 Mia! Plantation Rd
8208 Old Baucom Road
6200 Mia/ Plantation Rd
553-7008 6205 Firecracker
August 815
NO3 mg/l
3.8
1.5
1
4.4
2.6
4.1
20.9
2.1
0.1
1.6
24
0.7
2.8
2.7
1.7
4.7
4.6
7.1
2.5
5.2
12.4
1.3
13
0.3
4.7
6.3
4.1
TABLE 1-1
Private Well Nitrate Nitrogen Results and Water Supply/Service Status
Neuse River Waste Water Treatment Plant
Raleigh, North Carolina
DWQ 8123 Confirm 9111 January 118 Confirm 2120 April July Oct Jan'04
NO3 mg/L NO3 mg/L N03 mg/L NO3 mglL NO3 mg/L NO3 mgll NO 3 mglL NO3 mglL
6 .3 3 .4 N/A NIA NIA
3 1.4 1.6 1.6 N/A
0 .9 1.0 N/A NIA N/A
10.9 4 .3 4 .4 4 .8 NIA N/A
0.1 0.5 0.5 0.5 0.5 0.5
6 2.4 2.4 2.7 2.5
3.9 7.5 3.7 3.8 4.1 5.7
21 20 23.4 19.7 20.3 19.5 N/A
2.1 5 2 .2 2 .4 2.3 NIA
0.5 0 .5 NIA NIA NIA
1.7 1.4 NIA NIA NIA
23 23.5 52.9 20.3 23.1 20.3 NIA
0 .5 0.5 0.9 NIA NIA
5.9 2.5 3.1 3.2 3.5
6.4 3.1 3 .3 3.9 3.9
2. 1 2.1 2.1 2.1 2.3
10.3 4.4 4.7 4.7 5.1 5.6
8.4 3.8 4.6 3.9 3.7 4.4
7 15 6.2 7.3 6.6 5.7 7.2
1.9 2.9 3.0 3.1 3.2
5.2 13.5 6.5 7.4 7.7 6.9 NIA
9.7 11.6 16.2 15.2 14.4 18.0 NIA
7.4 2 .6 2 .9 NIA NIA
8.9 20.5 6-.9 8.5 8.7 8.7
0.Q o.s 0 .5 0.5 0.6
9.6 5 4.3 5.5 5.5 5.4
M 0,5 o.s 0.5 0.5
5.8 13.3 10.8 11.2 12.5 13.8 14.2
4.1 8.7 4.1 4.2 5.0 5.5 5.9
April'04 July'04 Oct'04 Bottle Water Bold indicates results greater GWQ std
Currently
NO 3 mglL NO3 mg/L N03 mglL STATUS
agreement rec 4/22, CONNECT 6/10/03, Well
N/A N/A NIA abandoned 11/26/2003
N/A NIA NIA
agreement rec 7/17, CONNECT 10/14/03, Well
abandoned 11/18/2003
NIA NIA NIA
agreement rec 4/25, CONNECT 6/10/03, Well
abandoned 11/17/2003
agreement rec 7/24, CONNECT 10/1/03, Well
N/A N/A NIA NL abandoned 11/26/2003
0.5 NIA NIA
agreement rec 12129/03, CONNECT 6/22/04,
Well abandoned 9/14/2004
2.6 2.5 1.3 aareement rec 4/16/04 CONNECT9/28/04
4.2 NIA NIA
agreement rec 12120/03, CONNECT6/1/04,
Well abandoned 09/09/2004
N/A N/A N/A
agreement rec 7/24, CONNECT 10/21/03, Well
NL abandoned 4/30/2004
agreement rec 10/28, CONNECT 11/18/03,
NIA NIA NIA Well abandoned 01/28/2005
agreement rec 4/25, CONNECT 5/29/03, Well
NIA NIA NIA abandoned 11/18/2003
City property, CONNECT5/29/03, Well
NIA NIA NIA ,. abandoned 11/18/2003
NIA N/A NIA
agreement rec 7/24, CONNECT 10/21/03, Well
NL abandoned 4/29/2004
agreement rec 4/30, CONNECT 7/14/03, Well
NIA NIA NIA abandoned 11/26/2003
3.2 NIA NIA
agreement rec 12/31/03, CONNECT6/2/04,
Well abandoned 9/13/2004
agreement rec 9/13/04,,CONNECT 10/13/04,
3 .7 3.7 6.4 Well abandoned 1/27/05
2 2.1 2.4
agreement rec 9/20/04, CONNECT10/19/04,
Well abandoned 12/06104
5.4 4.5 2.1
agreement rec 9/13/04, CONNECT10/12/04,
NL Well abandoned 1/27/05
3.9 2.9 1.0
agreement rec 9/20/04, CONNECT10/20/04,
Well abandoned 1/26/05
agreement rec 9/13/04,,CONNECT10/12/04,
6.5 7.4 7.3 NL Well abandoned 1126/05
agreement rec 11/29/04, CONNECT, Well
3.9 4.9 4.1 abandoned 1/26/05
NIA NIA NIA
agreement rec 7/24, CONNECT 10/22/03, Well
abandoned 4/28/04
NIA NIA NIA
agreement rec 7/24, CONNECT 12/2/03, Well
NL abandoned 4/28/04
agreement rec 5/14, CONNECT 8/13/03, Well
NIA NIA NIA abandoned 11/26/03
7 .8 4.4 6.1. X Active Well
0 .. 5 Q.5 0.5 not annlicable -water $ervice not 1:iv;,1ilabJe,
agreement rec 9/20/04,CONNECT11/16/04,
5.4 7.2 4.8 Well abandoned 1/26/05
0.5 0 .5 0 .. 5 declined water service 5/1 /03 (Active Well)
agreement rec 6/10/04, CONNECT9/16/04,
12.1 13.9 NIA NL Well abandoned 1/27/05
6.6 NIA NIA
agreement rec 12/07/03, CONNE.CT5/28/04,
Well abandoned 9/8/04
1 of2
WATE WELLS SAMPLED IN VICINITY OF NRWWTP ON DATES NOTED TO RIGHT
30
31
32
33
34
35
36
OWNER'S NAME
"
"
n
"
Debman Marda
Seawell, Virainia
Wheeler.. Pamela
Young, Evelyn
Belvin, Larry 37
38
39
. Mo-ore. l..ucv
40
41
42
43
44
HEATER UTILITIES
Mattress Albert
Wood,Wendv & Gerrv
Doremus, Stanlev & Joan
Mcfarlino, Mike & Beth
Norbera, Eric & Linda
Allemand Carlton & Lisa
Henderson Shanon
Coward Shirle v & Bill
High, Johnnie
Watkins, Glenda
Kina, Ronald
Debnam, Rene/la 45
~ ES:
Horne# Work# Address
" " 6309 Mial Plantation
" " 6317 Shotwell/ Mial Plant.
II II 28 62 Shotwell Road
II " 4608 Roads Hill
5532 Mia/ Plantation
266-1823 5529 Mia/ Plantation Rd
219-2629 6029 Mia/ Plantation Rd
772-4762 8537 Old Baucom Road
553-7188 291-0520 2757 Shotwell Rd
553-5936 823.2 Old 6aucorn Road
467-7854 St JAMES SUBDIVISION
119 Jamison Dr Ral
127 Jamison Dr Ral
143 Jamison Dr
165 Jamison Dr
546-3318 186 Jamison Dr
269 Jamison Dr
773-9843 2750 Shotwell Road
266-3935 5509 Mia/ Plantation Road
266-2496 5409 Mia/ Plantation Road
13 01-292-~221 5115 Mia/ Plantation Road
773-2303 2834 Shotwell Road
266-2387 5605 Mia/ Plantation Road
August 8/5
NO3 mg/L
15.4
7.6 .
5.5
4.3
3.1
5.8
17.8
31.8
1.~
These test wells are sampled triennially by the City and these analytical results have been provided by the City.
NL
NO3 Nitrate
mg/L milligrams per liter
Private water supply wells currently active (not abandoned)
TABLfl1•1 ' ·,' · · Private Well Nitrate Nitrogen Resutti and Wat,i Supply/Sorvlce Status
Neuse River Waste Water Treatrriont Plant
Raleigh, No~ Carolina ,..
DWQ 8/23 Confinn 9111 January 118 Confirm 2/2C April July Oct Jan'04
NO3 mg/L NO3 mg/L NO3 mg/L NO 3 mg/L NO~mg/L _ NO3 mg/L NO3 mg/L NO3 mg/L
18 17.2 37.4 18,4 21 .. 3 NIA NIA
7.8 13.9 7 4.8 8.5 NIA NIA
II . " . .. NIA NIA N/A
5.3 14.1 4.8 5.3 5.7 6.3 5.9
10.8 4.1 5.4 4.8 4.4 5.3
6 3.7 3.3 3 .0 3.1
5.2 15.1 7.7 8.5 11.5 11.9 14.5
16 15.1 38.5 12.5 18.4 18.5 NIA
3.2 2.8 2 4.7 2 .7 2 .2 NIA
2,.2 .2 1.8 0.5 1.1 1.0
16.7 8.1 8 .0 NIA NIA NIA
5 .3 0.5 0 .5 NIA NIA
3.2 6.2 10.417.1 5.2
6.4 3.6 3.5 4.0
6.4 2.6 2.6 3.2
5 5.6 5 .0 5.6
4.4
April'04 July'04
NO3 mg/L NO3 mg/L
NIA NIA
NIA NIA
NIA NIA
5.1 NIA
5.0 NIA
3.7 4.1
15.0 NIA
NIA NIA
NIA NIA
0.6 2 ,6
NIA NIA
NIA NIA
4.3 NIA
4.8 7 .. 5
3.3 2.5
5.9 2.7
NIA NIA
City of Raleigh is currently in the process of purchasing properties located on 8208 and 8232 Old Baucom Road (Lucy Moore). Upon purchase, the City will abandon the water wells located on these properties.
Oct'04 Bottle Water Bold indicates results greater GWQ std Currently
NO3 mg/L STATUS
N/A NL
agreement rec 6/9, CONNECT 8/4/03, Well
abandoned 11/17/03
NIA NL
agreement rec 6/9, CONNECT 8/7/03, Well
abandoned 11 /17 /03
N/A . served by 6317, CONNECT 817/03
NIA NL
agreement rec 12107/03, CONNECT5/25104,
Well abandoned 919104
NIA NL
agreement rec 3/11/04, CONNECT6/4/04, Well
abandoned 1/26105
0.6
agreement rec 718104, CONNECT9/24/04, Well
abandoned 1/26105
NIA NL
agreement rec 12130/03, CONNECT6/9/04,
Well abandoned 9/7/04
NIA NL
agreement rec 8/21, CONNECT 10/21/03, Well
abandoned 11 /26/03
NIA NL
agreement rec 8/14, CONNECT 10/22/03, Well
abandoned 4/29/04
1.2 declined water service 5/1/03 (A~tive Well), NIA NL agreement rec 4/12, CONNECT 4/25/03
NL see above
NL see above
NL see above
NL see above
NL see above
NL see above
NIA
agreement rec 5/9, CONNECT 8/14/03, Well
abandoned 11/18/03
agreement rec 12130/03, CONNECT6/9/04,
NIA NL Well abandoned 9114104
3.7 Active Well
1.9 Active Well
NIA
agreement rec 1/21/04,CONNECT 9/2/04, Well
abandoned 12/06/04
NIA agreement rec 9/20/04, CONNECT10/21/04,
Well abandoned1/26/05
2of 2
I
PIPE Flow Rate
SECTION GPM
Discharge Hose 2
A1-A2 6
A2-A3 4
A3-A4 6
A4-A5 8
A5-A6 10
A6-A7 12
A7-A8 14
A8-A9 16
A9-A10 18
A10-A11 20
A-11-A12 22
A-12-A13 22
A-13-B 22
B-D 44
D-E 66
E-F 80
F-G 80
G-H 80
H-1 80
1-J 80
J-K 80
K-L 80
L-M 80
M-N 80
N-0 80
0-P 80
PRELIMINARY PIPING HYDRAULICS
Groundwater Containment System
CORPUD -Neuse River Wastewater Treatment Plant
Raleigh, NC
EQUIVALENT LENGTHS OF PIPE FITTINGS
(NOTE: The spreadsheet is setup to calculate friction losses in 0.75, 1, 2, 3, 4, and 6-inch diameter pipes only)
PIPE PIPE NO. OF FITTINGS (FOR EQUIVALENT LENGTH CALC.)1 EQUIVALENl
DIAMETER LENGTH Check Valve Globe Valve 45EL 90 EL "T" RUN 'T"SIDE LENGTH(ft)
1 60.0 1 0 0 3 0 0 19.66
2 100.0 0 1 0 1 0 0 64.20
2 100 .0 0 0 0 0 0 1 10.30
2 100.0 0 0 0 0 0 1 10.30
2 100.0 0 0 0 0 0 1 10.30
2 100.0 0 0 0 0 0 1 10 .30
2 100.0 0 0 0 0 0 1 10.30
2 100.0 0 0 0 0 0 1 10.30
2 100.0 0 0 0 0 0 1 10.30
2 100.0 0 0 0 0 0 1 10.30
2 100.0 0 0 0 0 0 1 10.30
2 160.0 0 0 0 0 0 1 10.30
2 400.0 0 2 0 1 0 0 123.20
2 1360.0 1 1 0 0 0 0 82 .20
4 1080.0 0 0 0 1 0 0 10.10
4 600.0 1 0 0 0 0 0 45.20
4 2200 .0 0 0 0 0 0 0 0 .00
6 400 .0 0 0 0 1 0 0 15.10
6 600.0 0 0 4 0 0 0 32.40
6 600.0 0 0 1 0 0 0 8 .10
6 400.0 0 0 1 0 0 0 8.10
6 1000.0 0 0 1 0 0 0 8.10
6 800.0 0 0 1 1 0 0 23.20
6 1200.0 0 0 1 0 0 0 8.10
6 1000.0 0 0 2 1 0 0 31 .30
6 800.0 0 0 0 0 0 0 0.00
6 3600.0 0 1 0 6 0 0 262.60
TOTALEQ. Friction Loss 1
LENGTH (ft) (ft per 100 ft)
80 0.385
164 0.074
110 0.074
110 0.102
110 0.170
110 0.252
110 0.349
110 0.461
110 0.586
110 0.725
110 0.878
170 1.050
523 1.050
1442 1.050
1090 0.161
645 3.660
2200 0.470
415 0.057
632 0.057
608 0.057
408 0.057
1008 0 .057
823 0.057
1208 0 .057
1031 0.057
800 0 .057
3863 0.057
Total Loss=
NOTES:
1 = Equivalent lengths for fittings and valves and unit friction loss were obtained from Cameron Hydraulic Data , Edited by C.C . Heald, 19th Edition, Flowserve.
DISCHARGE HEAD
Friction losses 69 ft. of WC
Static pressure 15 ft. ofwc
Elevation head 126 ft. ofwc
DISCHARGE HEAD = 210 ft. of WC
Factor of Safety (25%) 52 ft. of WC
TOT AL DESIGN HEAD = 262 ft. Of WC
Total Loss
per Section
0~31
0.12
0.08
0.11
0.19
0.28
0.38
0.51
0.65
0.80
0.97
1.79
5.49
15.14
1.76
23.61
10.34
0.24
0.36
0 .35
0.23
0 .57
0.47
0.69
0.59
0.46
2.20
69