&EPA
Casper Winds, Wyoming
Case Study
RE-Powering America's Land:
Siting Renewable Energy on Potentially Contaminated Land and Mine Sites
The Casper Wind Project Uses a Collaborative Public Participation Process to
Successfully Site Renewable Energy on Contaminated Land in Wyoming
During an effort to remediate a former refinery, Chevron designated a different area of its property for the 16.5-megawatt
(MW) Casper Wind facility, creating a productive use for otherwise idle land. Though the project initially faced opposition in the
community, Chevron worked collaboratively through a public engagement process to respond to environmental and aesthetic
concerns and successfully complete the wind power-generating facility.
EPA's RE-Powering America's Land Initiative
Through its RE-Powering America's Land: Siting Renewable Energy on Potentially
Contaminated Land and Mine Sites initiative, the U.S. Environmental Protection Agency
(EPA) identified more than 11,000 EPA-tracked sites and nearly 15 million acres that
have potential for developing solar, wind, biomass and geothermal facilities. Using
potentially contaminated land and mine sites to develop renewable energy facilities
can:
Reduce development pressure on greenfields
Provide access to exisiting infrastructure, such as transmission lines and roads
Result in faster permitting and zoning times
Create jobs
Reduce blight and revitalize communities
In short, siting renewable energy on potentially contaminated sites contributes to
sustainable communities.
Ongoing Remediation of Refinery Site Limits Reuse Options
Casper, Wyoming, has a long history with the oil and gas industry; it has supported
petroleum refineries since 1895, with various refinery operations having been
established and closed over the years. The former Texaco Refinery was constructed
on the North Platte River near Casper in the early 1920s and was operational until
1982. It processed crude oil from local wells into gasoline, diesel fuel, asphalt and
petroleum coke, and at the time of closure, had a capacity of 21,000 barrels per
day. Decommissioning of the facility by Chevron began in 1995 and cleanup of
petroleum-contaminated soil and ground water has been ongoing since. Chevron
assumed responsibility for the refinery's cleanup in 1998, when the company merged
with Texaco. The site cleanup has been managed since by Chevron Environmental
Management Company (CEMC), In addition to the refinery that occupies the southern
portion of the site—the property includes 880 acres of industrial-zoned land
extending 3.5 miles north of the North Platte River. The property is divided into its
northern and southern portions by the River itself.
Under the Resource Conservation and Recovery Act (RCRA) Corrective Action Program,
Casper Wind's 17 turbines
What is RCRA Corrective Action?
The Resource Conservation and Recovery
Act (RCRA) Corrective Action Program is
run by EPA and 43 states and territories. It
is designed to investigate and guide the
cleanup of contaminated air, ground water,
surface water or soil from hazardous waste
management of spills or releases into the
environment. Releases of hazardous waste
and hazardous constituents are a result
of past and present activities at RCRA-
regulated facilities.
"Chevron's Casper, Wyoming, site not only
provided an excellent opportunity and location
for the company's first wholly owned wind
facility, but the Casper Wind Farm also brings
the former refinery site back into energy
production with renewable energy."
—Greg Vesey
President, Chevron Global Power Company
the entire property is subject to site-wide corrective action to clean up petroleum-
contaminated soil, ground water and surface water and protect the North Platte River from release of contaminants. CEMC is working
on the site's cleanup with the Wyoming Departmen t of Environmental Quality (WDEQ), the lead regulatory agency for the corrective
action under its Voluntary Remediation Program (VRP). Much of the site's contamination is confined to the southern portion, on
which refinery operations took place. The 880-acre northern portion was used for evaporation ponds that held treated refinery
wastewater. An investigation of sediment in the ponds on the northern portion of the property in 2006 showed levels of polynuclear
aromatic hydrocarbons (PAHs); however, it was determined that the ponds did not pose a threat to human health or ecology, and no

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Casper Winds, WY Case Study
Key Project Stakeholders
Site owner: Chevron Environmental
Management Company (CEMC)
Developer: Chevron Global Power
Financing: Chevron Global Power
Local government: Natrona County,
Wyoming
State agencies: Wyoming Department of
Environmental Quality (WDEQ)
EPA: RCRA, Region 8
Other federal agencies: U.S. Fish and
Wildlife Service
Utility: Rocky Mountain Power
A 1.5 MW wind turbine being installed
What are Renewable Energy
Credits (RECs)?
RECs are tradable certificates representing
electricity generated from renewable
resources. Renewable energy projects
create two products with value: 1) the
electricity generated, which can be
sold to utilities and consumers; and 2)
RECs, which often represent the avoided
emission of greenhouse gases (GHGs),
and can be sold, traded or bartered.
Utilities and other parties may purchase
RECs from renewable power generators
to comply with state requirements or
voluntary green power standards. Though
the market for RECs is still developing, the
sale of RECs can potentially help finance
renewable energy projects.
cleanup was necessary. WDEQ designated the property as a "Use Control Area"(UCA)
with institutional controls established to restrict the property's future use.
Based on human health and ecological risk assessments, the WDEQ agreed in June
2007 to develop a separate VRP remedy agreement for the site's northern portion in
order to facilitate its reuse. Making use of a separate VRP remedy agreement allowed
for remediation and reuse of this less-contaminated portion of the property in
ways that ensured the safety of human health and the environment. Selected non-
contaminated areas of the property's northern portion were identified as appropriate
for industrial use (including facilities for treating impacted ground water), while other
areas along the North Platte River were deemed safe for recreational use.
The Property's Northern Portion is Evaluated for its Wind
Power Potential
Chevron Global Power Company (CGP) develops, generates and sells power and
associated services and currently operates over a dozen power generation facilities
worldwide. CGP saw promise in the property's northern portion for a small-scale,
commercial wind project because of its excellent wind energy potential.
The Casper site was CGP's first wind power project. Chevron began assessing
the area for its wind power potential in 2006 using three metrological towers
erected around the site. The site's average potential for wind energy production
of 500-600 watts per square meter of land at a height of 50 meters puts the site
in the top 10% of locations in the United States for wind speed and reliability. The
company identified the optimal location for 13 planned 1.5 MW turbines, including
connecting power lines and a substation, based on wind speed, constancy and
proximity to existing power lines (from the site's industrial past).
Many sites with excellent wind potential are located in remote areas far from
existing infrastructure, and the high cost of building electrical transmission
infrastructure can be prohibitive for new wind projects. The Casper site's existing
electrical transmission infrastructure gave the project built-in capacity for installing
the wind turbines and connecting them to the electrical grid. Chevron cited this
property's location as a significant driver for wind power development, as it enabled
the company to avoid the substantial cost of constructing roads and power lines.
Financing for the Project is Provided by Chevron Global Power and by a
PPA with PacifiCorp
Chevron secured a long-term a power purchase agreement (PPA) with the local
utility, Rocky Mountain Power for the electricity it would generate. PPA agreements
between utilities and developers are contracts to purchase the electricity and
Renewable Energy Credits (RECs) generated at the site. PPAs significantly reduce the
risk associated with renewable energy projects by creating a long-term market for
the electricity generated.
As is the case with many renewable energy developers, Chevron's financial feasibility
data inputs are considered proprietary information and cannot be disclosed
publicly. For most projects, the search for investors and lenders can be a time-
consuming element of the renewable energy development process, as investors
have their own financing criteria to consider in addition to those of the developer.
In this case, financing was expedited because Chevron Global Power was able to
carry the full financial risk of the Casper Wind project and independently evaluate
the project based on its own criteria for return on investment. The project qualified
for the federal Renewable Energy Production Tax Credit, which provides a 2.1 C
per kilowatt-hours (kWh) tax credit for electricity generated, generally for 10 years
after the date the facility is placed in service. In lieu of the Production tax credit,
1 WMErieiqy.moumMmQftheUnmdS1xim pub. No..DSE?CH 10093-4 National Renewable Energy Laboratories, U.S. D©E, T986. w«w:nrel.g»?gls/\fl/ind
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Casper Winds, WY Case Study
the facility also qualified for an Investment Tax Credit, or a grant in place of either tax credit, under the American Recovery and
Reinvestment Act of 2009.
Chevron Addresses Environmental Concerns in the Permitting and Approval Process
The project required approval from WDEQ to disturb soil by excavating tower
foundations at the site. In addition, a conditional use permit from the Natrona
County Planning and Zoning Commission was required to begin construction
and develop the land as a wind farm.The site's UCA status prohibited Chevron
from disturbing the soil, but in 2007, WDEQ provided a determination that soil
on the northern portion of the property was not contaminated,
permitting Chevron to excavate for improving roads and erecting
turbines and electrical feeder lines. Permission from County
authorities was more difficult to obtain, as this was the first
proposed wind farm in Natrona County and there was some
opposition from nearby residents based on aesthetic and health
concerns.
The portion of Chevron's property considered for wind power
development is adjacent to Brookhurst and Sandy Lakes,
neighborhoods zoned for rural residential and urban agricultural
use. While the entire refinery site had always been industrial land
and an energy transmission corridor, the part of the site adjacent
to Sandy Lakes was undeveloped. While several neighbors were
supportive of the project, others were concerned about the visual
impact of the towers and the noise they would generate. Some
residents with property adjacent to the site questioned the safety
of the towers and voiced concerns that buffer zones around each
turbine would prevent them from being able to develop their
land.
"We've seen here in Casper that community
involvement early is necessary and beneficial."
—Bill Reese
Project Manager, Chevron Global Power
Timeline of Key Project Steps
1982: Texaco CasperWorks Refinery closes
1986: Refinery is decommissioned and environmental
remediation begins
1998: CEMC assumes liability for cleanup following Chevron-
Texaco merger
2006: CEMC proposes wind power development on the North
North Property
2006: An ecological risk assessment for the North Property
shows no evidence of contamination in the area being
considered for wind power
2006: Chevron installs meteorological towers to evaluate the
site's suitability for wind power; begins meeting with local
government and community members
2007: WDEQ allows separate VRP remedy agreement for
less contaminated North Property, allowing reuse subject to
institutional controls
March 2008: USFWS evaluates potential avian mortality from
wind turbines
December 2008: Natrona County grants permission for
redevelopment of former refinery property as industrial/
commercial site
February 2009: Natrona County grants a conditional use
permit allowing the installation of 11 wind turbines
June 2009: Construction of the CasperWinds Facility begins
December 2009: CasperWinds begins generating electricity
The public's environmental concerns included the project's
effect on vegetation, birds and wildlife habitat, in addition to the
potential for releasing contaminants and dust from excavation.
Ponds on the property provide a source of water to aquatic birds
in an otherwise arid landscape. Concern over potential bird and
bat mortality led to an avian and bat study by a Chevron Global
Power subcontractor. A three year wildlife study was conducted
prior to construction. The studies determined that potential
impacts on birds and wildlife from the project would be minimal
because of the wide spacing between the turbines. To reduce
the potential effect on birds, CEMC adjusted the locations of the
turbines, eliminating two of the 13 proposed turbines nearest
to the ponds. Scaling back the project was not required, but the concession to this environmental issue increased the project's
feasibility in the planning and permitting process.
Addressing public concern over the project's impact was essential to the viability of the project. Before funding was approved by
Chevron and building permits were issued, CGP began seeking community input. Chevron Global Power Company began holding
public meetings in 2006 to open dialogue with the community and gather input on environmental, social and community issues
associated with the proposed wind farm. Chevron involved representatives from the local government and WDEQ, and presented
wind and environmental impact studies. Over a three-year period, 25 public meetings were held to discuss and resolve these
aspects of the project.
The project had the support of local officials, including the mayor of nearby Evansville, who saw Casper Winds as a win for the
community in providing clean energy and an increased tax base. Two additional proponents of the project included the Casper
Area Chamber of Commerce and Casper College, which created a renewable energy program that could provide a skilled
workforce for the Casper Wind Farm and other wind power projects in the state.
2 Chevron Environmental Management Company Former Texaco Casper Refinery Draft Remedy Agreement. WDEQ, 2009
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Casper Winds, WY Case Study
Natrona County Clarifies Zoning for Wind Power and Approves the Project
The Casper Wind project was the first proposed commercial wind project in Natrona
County; there were no existing county zoning regulations regarding wind turbines.
Responding to the community's concern over the Casper Wind project, the county
adopted regulations for wind energy in September 2008. According to the amended
zoning rules, developers must apply for a conditional use permit and meet the
regulation's siting guidelines. Under the regulations, each turbine is required to have
a buffer zone with a radius 10 percent wider than the tower height (e.g., a 440-foot
radius for Casper Wind's 400-foot towers) and be located at least a quarter mile from
any structure. The regulations also require an interior buffer around the edge of the
property. While the amended zoning rules did not substantially change the design
of the project, Chevron modified the placement of the tower to conform to the
buffer requirement and mitigate potential impacts on birds.
In February 2009, the Natrona County Board of Commissioners granted Chevron's
request to permit the installation. The Board's decision took the objections of neighbors into account, but granted the conditional
use permit, reasoning that the land had been an energy corridor and that the project now conformed to the new county
regulations on wind farms. The Casper Wind project as planned had met all the zoning requirements, but complaints from nearby
landowners revealed a need for more comprehensive zoning regulations. Anticipating a growing need for clarity in its wind power
zoning to help avoid disputes between landowners and developers in the future, the county amended the regulations it had
adopted in response to the Casper Wind Power project. The revised regulations give the Board of Commissioners more control
over granting conditional use permits and enable the public to better participate in the permitting process. The regulations
establish a half-mile buffer between wind turbines and established municipalities, require the developer to provide studies on
noise from turbines, and provide for decommissioning projects and land reclamation.
Technical Specifications
•	RE technology installed: GE Energy 1.5 MW
SLE Model Wind Turbines on 60m towers
•	Maximum generating capacity:
1.5 MW per turbine (16.5 MW total)
•	Expected system life: 20-25 years
•	Reduction in GHG emissions:
40,827 tons of carbon dioxide annually
•	Jobs leveraged: Approximately 20
construction jobs, 1.5 permanent jobs
Construction Begins on Casper Wind Project
The project broke ground in June 2009, when Chevron began building and improving access roads and constructing tie-in lines to an
existing substation. In the fall of 2009, eleven GE 1.5 MW turbines were installed on the property's northern portion. Other structures
on the site include one permanent meteorological tower and an operations and maintenance building. The wind farm began
commercial operations in December 2009. According to Chevron, the 16.5 MW-capacity wind farm generates enough electricity
to meet the annual need of approximately 4,000 homes. During construction, Chevron used approximately 20 local contractor
companies. After completion, a Casper native became the operations and maintenance manager of the site, a full-time position
created by the Casper Wind Farm. The project also created one full time and one part-time operations and maintenance position.
Casper Wind Benefits Chevron and the Community
The Casper Wind project took three years to go from planning to operation: the
monitoring towers were installed in 2006, environmental site preparation was
completed in 2007, and 25 public meetings were held from 2007 through 2009.
Though the project initially faced some opposition on environmental and aesthetic
grounds, the developers'transparency and engagement with local authorities and the
public were key contributors to its eventual success.
This formerly idle and environmentally degraded land is now a symbol of
environmental stewardship that benefits Chevron, the community and the
environment. While cleanup options are still being explored for the southern portion
of the property where refinery operations took place, Chevron was able to return the
property's northern portion to productive and sustainable use, diversify the company's energy assets with renewable wind energy,
and enhance their capacity for developing wind power projects at other Chevron facilities. Natrona County benefits from expansion
of its power grid with an emissions-free energy source, new jobs and an expanded tax base due to the increased property value
of the developed site. While development of the county's first wind power project caused contention among some neighbors, the
county used the experience to clarify its regulations for managing future renewable energy development. The completed project
highlights the value of collaboration between business, government and community stakeholders for successful renewable energy
development.
Contacts For More Information
Chevron Global Power Company:
(877) 240-4446, power@chevron.com
WDEQ Voluntary Remediation Program:
Paige Smith: (307) 777-2440,
psmith@state.wy.us
EPA Region 8: Nathaniel Miullo,
Revitalization/Clean Energy Advisor:
(303) 312-6233, Miullo.Nat@epa.gov
For more information, visit www.epa.gov/renewableenergyland or contact deanenergy@epa.gov
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