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Site Visit Report 

Chesterfield Power Station 

 500 Coxendale Road 

 Chester, VA 23836 

March 10, 2009 

1.0 Background and Objectives 

The Environmental Protection Agency (EPA) is in the process of developing 

316(b) cooling water intake structure requirements that reflect the best technology 

available (BTA) for minimizing adverse environmental impact for all existing 

power plants and manufacturing facilities. As part of this process, EPA staff is 

visiting electric generators and manufacturers to better understand the cooling 

water intake structure (CWIS) technologies in use at typical facilities, including 

the site-specific characteristics of each facility and how these affect the selection 

and performance of CWIS technologies. EPA is also visiting facilities to better 

understand cooling water use and specific issues or technologies that can affect 

316(b) compliance. Chesterfield Power Station was selected for a site visit due to 

its proximity to EPA Headquarters and its use of combined cycle generation. 

2.0 Facility Description 

The Chesterfield Power Station is owned and operated by Dominion Virginia 

Power (Dominion). It is located on approximately 150 acres in Chester, Virginia 

just outside of Richmond. Chesterfield is the largest fossil-fueled power station in 

the Dominion System. It began operation in 1944 and employs approximately 

255 people. 

Chesterfield withdraws cooling water from the James River, a tidal river, and 

discharges to both the James River and the Farrar Gut Canal. Cooling and 

process water withdrawals and wastewater discharges are currently regulated 

under NPDES permit VA0004146 which will expire on December 9, 2009. 

3.0 Electricity Generation and Transmission 

Chesterfield has four pulverized coal-fired units and two combined cycle gas/oilfired units. Units 3, 4, 5 and 6 are coal-fired baseload units with generating 

capacities of 106 MW, 176 MW, 337 MW, and 690 MW, respectively (gross 

summer capacity). Unit 3, the oldest, began operation in 1952, followed by Unit 

4 in 1960, Unit 5 in 1964, and Unit 6 in 1969. Original Units 1 and 2 are 

permanently out of service. The fuel source for all four units is Eastern 

Bituminous Coal.1

 

1

 Chesterfield maintains a one month coal supply on-site. 
2

Chesterfield’s two combined cycle units are peaking units that cycle depending on 

fuel cost, demand, and other factors. Chesterfield is part of the PJM regional 

transmission organization which dictates the facility’s daily power generation. 

These units, referred to as Unit 7 and 8, have generating capacities of 200 MW 

and 204 MW (gross summer capacity), respectively and began operation in 1990 

and 1992.2

 While they can use natural gas or fuel oil, these units primarily use 

natural gas. 

Chesterfield performs routine maintenance on its generating units in the fall or 

spring. The facility typically maintains different units each time. The length of 

each shutdown period associated with maintenance varies with the type of 

maintenance or upgrade being performed. For example, facility representatives 

noted the outages have ranged from three to 90 days.3

The transmission system is also owned by Dominion but is operated by a different 

business unit. 

4.0 Cooling Water System and Intake Structure 

There are three CWISs providing once-through cooling water: Units 5-6 in one, 

Units 3-4 in a second, and Units 7-8 in the third (moving downstream).4 These 

CWISs are located on an “outer bend” curve in the James River downstream from 

Richmond and well below a smallmouth bass fishery. The James is a tidal river 

with approximately 3 foot tides in the summer. The river depth directly in front 

of the screens is approximately 85 feet, which is unusually deep for a riverine 

environment. The remainder of the river is more typical; because the James is a 

navigational river, the Army Corp of Engineers dredges to maintain a depth of at 

least 35 feet. Depending on seasonal rainfall, the salt wedge in the James River 

has moved past Chesterfield and into Richmond in the summer. 

Each CWIS is fitted with a trash rack and standard (i.e., coarse mesh 3/8”) 

traveling screen. The screens for Units 3, 4, 7, and 8 are eight feet wide and the 

screens for Units 5 and 6 are ten feet wide. The through-screen velocities range 

from 1.5 to 2.5 feet per second (fps). All of the screens are about 18-20 feet deep 

and rotate when the pressure differential across the screen reaches a specified 

amount. When the differential is reached, the screens rotate and are cleaned with 

a high pressure spray that flows into a debris trough which discharges to the 

James River. Each unit has two screens and one pump per screen. The design 

intake flow (DIF) for all units combined is calculated as 1245 MGD with an 

average actual intake flow (AIF) of 836 MGD. 

Facility representatives indicated they have had no issues with screen operation. 

Chesterfield does not have regularly scheduled overhaul or maintenance periods 

 

2

 Units 1 and 2 were replaced by Units 7 and 8. 

3

 A recent scrubber tie-in on Unit 6 required a 90 day outage. 

4

 The existing CWIS for the since-retired Units 1-2 was used for Units 7-8. 
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for the CWIS. Rather, it performs CWIS maintenance and overhaul on an asneeded basis. Plant outages in the fall and spring have historically provided 

adequate time for any CWIS maintenance. 

Units 4-6 discharge cooling water via a discharge canal into Farrar Gut which 

ultimately discharges back into the James River. Chesterfield is the only direct 

source of water to the Farrar Gut Canal; facility representatives indicated Farrar 

Gut Canal was closed off and would run dry without the cooling water discharge. 

Units 3, 7, and 8 discharge cooling water directly into the James River. 

5.0 Impingement and Entrainment Information 

Chesterfield collected impingement samples in 1977 and again in 2005/2006. In 

order to facilitate comparison of the data, Chesterfield used the same procedure 

and methodology during both sampling periods. During the sampling periods, 

Chesterfield conducted impingement sampling two times a month for a year for a 

total of 24 sampling events. During each 24-hour sampling event, 16, 10- minute 

screen-wash samples were collected at 0800, 0900, 1200, 1300, 1400, 1500, 1800, 

1900, 2000, 2100, 2400, 0100, 0200, 0300, 0600, and 0700 hours. Samples were 

collected in five baskets, consisting of 3/8-inch mesh, and one dip net in the 

screen-wash troughs for each unit. 

The table below shows results from the two impingement studies. The facility 

collected 14 common species during the two sampling periods. While the species 

generally remained the same, the dominant species changed between the first and 

second sampling period. During the 1970s, the dominant species was alewife, 

while the dominant species in the recent sampling was clupeids. Herring and 

alewife are not observed as often in the more recent sampling. 

 Sampling Period 

1977 2005/2006 

Number of species collected 23 21 + 3 shellfish1

Primary species Hogchoker 

Spottail shiner 

Alewife 

Blue catfish2 

Blueback herring 

Channel catfish 

Bluecrab 

Total number of fish collected 441 159 

1

 The facility did not sample for shellfish during the 1977 sampling period. 

2

 Due to stocking, the river has recently become a fishery for blue and flathead catfish. 

During the 2005/2006 sampling period, Chesterfield also collected entrainment 

samples and conducted ambient studies. Concurrent with the impingement 

sampling, Chesterfield collected entrainment samples for both fish and shellfish 

eggs and larvae in front of the screens for Unit 6.5

 During each sampling event, 

 

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 Since Unit 6 is the largest generating unit, it was selected as the “worst case” scenario for entrainment. 
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duplicate 10-minute samples were collected from near bottom, mid-depth, and 

near surface locations four times during the 24-hour period, centered around: 

1000, 1600, 2200, 0400 hours. Samples were collected with 1⁄2 m diameter mouth 

plankton nets constructed of 505-μm netting, each affixed in a double-net bongo 

frame. A mix of eggs and larvae with clupeids and Dorosoma (gizzard shad) 

representing 43% and 35%, respectively were collected. The facility also 

entrained a smaller percentage of Mysid Shrimp and blue crab. 

In conjunction with each entrainment sample, samples were also collected via 

tows from the James River upstream, downstream, and adjacent to the intake 

centered on the 1000, 1600, 2200, and 0400 hours. During ambient studies, the 

facility collected 1,106 fish during four surveys. The ambient ichthyoplankton 

tows mirrored the entrainment results. 

6.0 Cooling Tower Feasibility 

Chesterfield has not performed any cooling tower feasibility studies; facility 

representatives noted monetary and space concerns especially in light of its recent 

capital expenditures and facility expansion for air controls. Other factors that 

may affect cooling tower installation are an adjacent county park and the close 

proximity of the boilers to the river (reducing the available space for tie-in). 

7.0 Debris Handling 

Chesterfield does not have significant problems with debris loading. It 

experiences an influx of leaves in the fall, but facility representatives indicated 

this hasn’t negatively impacted facility operations. 

8.0 Repowering/Future Uses 

Chesterfield has no current plans for re-powering or upgrades other than 

additional air controls. See Section 13.0. 

9.0 Cooling Ponds 

 

There are no cooling ponds on site. 

10.0 Ownership 

Chesterfield is owned by Virginia Electric and Power Company d/b/a Dominion 

Virginia Power, a subsidiary of Dominion Resources, Inc., an investor-owned 

company. 
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11.0 316(a) 

Chesterfield has a 316(a) BTU heat rejection requirement, but has had no 

problems meeting its limit. No seasonal derating has been necessary. 

12.0 Ash Handling 

Bottom and fly ash from Units 3-6 are handled wet. A small portion of the 

bottom ash is sold, while the remainder is commingled with the fly ash and 

sluiced to the ash pond. 

Chesterfield has two ash ponds that began operation in the 1960s and 1980s, 

respectively. The older pond is unlined and is still active. The newer pond is 

unlined and is being closed with ash. The active newer pond is approximately 80 

feet above grade. The plant expects that when it is completely filled, in 

approximately 2020, it will be 160 feet above grade. In addition, flue gas 

desulfurization (FGD) wastewater treatment purge also discharges to this ash 

pond. The pond has a general nutrient discharge permit that requires monitoring 

of TSS, oil and grease, and nitrogen. 

 

13.0 Air Emissions Controls 

Chesterfield employs low NOx burners on Units 3-6 and SCRs year round on 

Units 4-6. The facility noted it achieves 90% NOx reductions during the ozone 

season (May 1-September 30) and 75 % NOx reductions during the remainder of 

the year. The facility also employs electrostatic precipitators on Units 3-5 and a 

baghouse on Unit 6 for PM (particulate matter) control that are 96-99% efficient. 

In 2008, Chesterfield began operating a limestone forced oxidation (LSFO) FGD 

on Unit 6 for SO2 removal. The facility noted the scrubber’s efficiency exceeds 

95% and prevents the emission of 30,000 tons of SO2 annually. The FGD 

blowdown is based on the level of chlorides in the absorber vessel, which are 

typically kept between 24,000-25,000 ppm (scrubber design may not exceed 

30,000 ppm chlorides). The FGD purge is sent to the wastewater treatment 

system. Gypsum is barged and sold off-site for beneficial reuse. 

The FGD wastewater treatment system consists of a DensaDeg clarifier, pH 

adjustment with lime and polymer addition for greater settling of solids. The FGD 

waste stream is an internal discharge that discharges to the ash pond. Proctor’s 

Creek (a nearby wastewater treatment plant) effluent is used as make-up water for 

the scrubber. 
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Chesterfield plans to install a single wet LSFO FGD scrubber for Units 3, 4, and 5 

in 2012.6 The facility projects this additional scrubber to reduce overall SO2

emission by at least 95%. 

Chesterfield’s 2008 enhanced environmental control system additionally included 

a fabric filtration baghouse (the largest in the U.S.) on Unit 6 that removes greater 

than 99% of PM. Chesterfield noted that the combination of the new scrubber 

and baghouse system is also expected to reduce mercury air emissions by 90%. 

Chesterfield noted that the enhanced environmental controls more than doubled 

the size of the power station and that the total costs of environmental expenditures 

associated with the existing SCRs, FGD, baghouse, and scrubber were $750 

million. It took the facility 4 years to complete installation of these systems. 

14.0 Additional Information 

With regard to the 2004 316(b) Phase II rule, Chesterfield completed its 

biological studies including impingement and entrainment estimates. Facility 

representatives indicated that determining the calculation baseline was 

straightforward because they are a shoreline facility with traveling screens. The 

facility did not complete technology feasibility evaluations nor did they come to 

conclusions as to how they would have complied with the 2004 rule. However, 

Chesterfield representatives indicated they liked the flexibility that the 2004 rule 

offered. They thought it was imperative that the new rule offer multiple 

compliance options to allow each facility to accommodate site-specific issues. 

Specifically, Dominion Power representatives would like to see rule options that 

provide credit for flow reductions, a suite of technology options that 

accommodate site-specific characteristics, and water body considerations. 

In the 1960s, a series of aerators were installed in the discharge for Units 4-6 (in 

Farrar Gut Canal) to improve water quality in the James River. However, these 

have not been used in many years. 

Attachments 

Attachment A List of Attendees 

Attachment B Aerial Photos 

Attachment C Site Visit Photos 

 

 

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 Facility representatives noted that the single scrubber for Units 3, 4, and 5 would be about the same size 

as the scrubber for Unit 6. 
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Attachment A--List of Attendees 

Paul Shriner, EPA 

Jan Matuszko, EPA 

Josh Hall, EPA 

Erik Helm, EPA 

Julie Hewitt, EPA 

Richard Witt, EPA OGC 

Shari Goodwin, Tetra Tech 

Kelly Meadows, Tetra Tech 

Peter Sherman, Tetra Tech 

Christine Wong, Tetra Tech 

John Sunda, SAIC 

Dawn Garber, Dominion 

Bill Bolin, Dominion 

Oula Shehab, Dominion 

Cathy Taylor, Dominion 
Copyrighted page/s removed. Copyrighted 

material is not available in Regulations.gov since 

it may not be reproduced without consent of the 

copyright holder. 

Please contact the EPA Docket Center, Public 

Reading Room to view this document. 

Address: 1301 Constitution Ave, NW 

Room 3334 

Washington, DC 20004 

Telephone: 202-566-1744 

Fax: 202-566-9744 

Email: docket-customerservice@epa.gov
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Attachment C—Site Visit Photos 

Please see the attached materials.