The Casper Perchloroethylene (PCE) Plume Orphan Site is approximately 150 acres in an area that is bound to the north by the North Platte River, the south by East 5th Street, the west by Center Street, and the east by Bryan Stock Trail. The area is comprised of residential, commercial and industrial neighborhoods. Environmental testing in the late 1980s revealed the presence of PCE in groundwater in downtown and north Casper, as well as in the indoor air of some homes.
The Wyoming Department of Environmental Quality (DEQ) has designated the Casper PCE Plume Orphan Site as a high priority orphan site. The designation is due to the number of people in proximity to the plume, the discharge of the plume into the North Platte River, and the carcinogenic nature of PCE. When funding has been available the DEQ has continued to investigate, monitor, and remediate the plume.
Currently, the DEQ is monitoring the effectiveness of the remedies implemented to remediate the PCE plume. If you have any questions about the project, please contact the Project Manager, Matt Buchholz at 307-777-8937 or at firstname.lastname@example.org.
Recent Public Meetings:
- March 28, 2017: The DEQ held a public meeting to inform concerned parties about the plan to remediate the PCE plume.
Site Investigation Milestones:
- November – December 2009: The DEQ installed groundwater monitoring wells and soil vapor sampling points throughout the study area.
- March 2010 – March 2011: The DEQ tested indoor air and subslab soil gas at potentially affected properties.
- June 2010 – August 2011: The DEQ installed indoor air mitigation systems at residential and commercial buildings.
- August 2011: Installation of additional groundwater wells along the northern portion of the plume.
- Spring 2014: The DEQ used High Resolution Site Characterization (HRSC) techniques to investigate a source area to acquire information that would allow a Remedial Alternatives Evaluation to be completed. During this work the DEQ was able to show another PCE plume (further upgradient) was contributing to the Casper PCE plume.
- Spring 2015: The DEQ approved the Source Characterization Report (1/9/15), allowing the DEQ to evaluate remedial alternatives.
- May 2016: The DEQ approved the Remedial Alternatives Evaluation Report (RAER) (5/9/16), which included a recommendation to do additional HRSC at the furthest upgradient source. The RAER suggested implementing Soil Vapor Extraction (SVE) in conjunction with Enhanced In-Situ Bioremediation (EISB) for the source of the plume, and Monitored Natural Attenuation (MNA) for the rest of the plume.
- July 2016: The DEQ completed the HRSC investigation (7/11/16) at the furthest upgradient source.
- November 2016: The DEQ approved the SVE work plan (11/1/16).
- May 2017: The DEQ approved the EISB work plan (5/3/17).
- July 2017: The DEQ received the SVE installation report (7/10/17).
- July 2017: The DEQ approved the MNA work plan (7/13/17).
- October 2017: The DEQ received the EISB remedy completion report (11/17/17).
The Cheyenne Airport Addition is located at 112 East 8th Avenue in the City of Cheyenne. At one time, the site served as the location for the original Cheyenne airport hangars. It later became the United Airlines maintenance/overhaul facility until 1947. The site remained vacant for many years until Blood Systems Inc. (DBA United Blood Services) purchased the property in 1994. A Phase I Environmental Site Assessment indicated the potential for contamination related to historic site use. A subsequent Level II Environmental Site Assessment (Empire Laboratories, Inc. 1994) documented chlorinated solvent impacts to groundwater above maximum contaminant levels (MCLs).
The Cheyenne Airport Addition has been evaluated as a high priority site for the Wyoming Department of Environmental Quality/Orphan Site Remediation Program (WDEQ/OSRP). Existing groundwater contamination at the site and the risks that it may pose to human health and the environment are the basis for additional investigation. Recent state funds, allocated to the WDEQ/OSRP, made the 2014 site investigation possible.
WDEQ/OSRP Project Manager:
Site Investigation Updates:
- Prior to the purchase of the property by Blood Systems, Inc., a Phase I Environmental Site Assessment was conducted.
- October 1994: An investigation confirmed environmental contamination related to historic site use.
- July and August 2014: A field investigation was conducted to delineate site soil and groundwater investigation, and evaluate the vapor intrusion pathway.
- December 2014: 2nd quarterly groundwater, subslab, and indoor air data were collected.
- March 2015: 3rd quarterly groundwater, subslab, and indoor air data were collected.
The Cheyenne Perchloroethylene (PCE) Plume orphan site is an area approximately 20 acres in size within a roughly 5 block by 3 block area of downtown Cheyenne, Wyoming. The site is centered 1 block directly west of the Herschler Building, 122 West 25th Street, Cheyenne and consists of a mixture of single and multi-home residential properties, government buildings, and commercial businesses. The chlorinated solvent contamination was first discovered in soil and shallow groundwater (5 to 15 feet below ground surface) following a Limited Subsurface Investigation conducted in December 2002 by ERM on behalf of the former Safeway Store located at 2512 Pioneer Ave, Cheyenne.
Wyoming Department of Environmental Quality (DEQ) Project Manager:
Carol Stark, Project Manager, 307-777-8759, email@example.com
February 17, 2010 held at the Herschler Building, 122 West 25th Street, Cheyenne, WY
Site Investigation Update:
- October 2009: Site investigation began with the sampling of existing groundwater supply wells and sumps
- November -December 2009: The DEQ installed 17 groundwater monitoring wells and 44 permanent soil vapor sampling points throughout the study area
- January 2010: Public notice was initiated using mailings to residents within the study area and newspaper notices
- February 2010: A public meeting was held at the Herschler Building, Cheyenne on the 17th to notify residents of site investigation results
- March 2010: The DEQ began indoor air testing of potentially affected properties (43 locations)
- May 2010: Installation of indoor air mitigation systems began (12 properties)
- July 2010: The site investigation of groundwater and soil gas was expanded along the western edge of the study area, and source investigation into an abandoned underground storage tank was begun
- February - May 2011: DEQ continued indoor air testing of potentially affected properties (27 additional properties)
- February - June 2011: Installation of indoor air mitigation systems continued (10 properties)
- July 2011: Site investigation of soil gas was further expanded along the western edge of the previous expanded area as well as to the south.
- November 2011: Completion of indoor air testing of potentially affected properties (4 additional properties)
- March 2012: Site Investigation Report completed. Initial site investigation activities completed. DEQ begins evaluation for additional investigation requirements and/or remediation of groundwater.
- Spring 2017: Anticipate development of a Remedial Alternatives Evaluation, including additional data collection as needed
Deluxe Cleaners and Tailors (Site) is located at 1614 House Avenue in Cheyenne, Laramie County, Wyoming. The Site is an 8,712 square foot parcel bordered on the east by House Avenue, on the north by East 17th Street, on the west by a vacant parcel and on the south by an alley.
A July 25, 2007 investigation revealed the presence of the volatile organic compounds (VOCs) perchloroethylene (PCE), trichloroethene (TCE) and dichloroethene (DCE) in the soil and the groundwater samples taken from the Carl’s Jr. Restaurant property, south of the Site. These VOCs are commonly associated with dry cleaning operations. Furthermore, the direction of groundwater flow suggests the Deluxe Cleaners and Tailors dry cleaning business as the likely source. In 2008, the Department of Environmental Quality (WDEQ) Voluntary Remediation Program (VRP) recommended the Site be entered into the VRP to address impacts from contamination of chlorinated solvents. The Site was entered into the VRP on September 15, 2009. On November 30, 2011, the Site was withdrawn from the VRP after determination that Deluxe Cleaners and Tailors was not viable and therefore eligible for the Orphan Site Remediation Program (OSRP).
Wyoming Department of Environmental Quality (DEQ) Project Manager: P.J. Wilber, Senior Project Manager, 307-777-7746, firstname.lastname@example.org