DERR-2025-006190

195 North 1950 West • Salt Lake City, UT
Mailing Address: P.O. Box 144840 • Salt Lake City, UT 84114-4840
Telephone [phone] • Fax [phone] • T.D.D. 800 346-3128
www.deq.utah.gov
Printed on 100% recycled paper

Governor

DEIDRE HENDERSON
Lieutenant Governor
Department of
Environmental Quality

Tim Davis
Executive Director

DIVISION OF ENVIRONMENTAL
RESPONSE AND REMEDIATION

Brent H. Everett
Director
ERRC-185-25

August 21, 2025

Peter Brinton
Senior Reclamation Engineer, PacifiCorp
1407 West North Temple, Suite 110
Salt Lake City, Utah 84116

RE: Response to Memorandum - Former PacifiCorp Carbon Power Plant #C095
Helper, Carbon County, Utah

Dear Mr. Brinton:

The Division of Environmental Response and Remediation (DERR) received a memorandum
dated May 27, 2025, on the subject of: Characterization and Management of Coal and Coal Combustion
Residuals (CCR) at Former Carbon Plant (Memorandum), submitted in regards to the Former Carbon
Power Plant Voluntary Cleanup Program (VCP) Site (Site). The Memorandum outlines PacifiCorp’s
position that coal and CCR beneficially used at the Site are not subject to Resource Conservation and
Recovery Act (RCRA) regulatory requirements that would necessitate their testing, management, or
disposal as anything other than a non-hazardous solid waste.

Coal combustion residuals are “fly ash, bottom ash, boiler slag, and flue gas desulfurization
materials generated from burning coal for the purpose of generating electricity by electric utilities and
independent power producers.” Utah Admin. Code R315-319-53(10). Under Utah Admin. Code R315-
319-53(8)(i)-(iv), CCR is “beneficially used” if (1) the CCR provides a functional benefit; (2) the CCR
substitutes for the use of a virgin material; (3) the use of CCR meets relevant product specifications,
regulatory standards, or design standards if available, and if those standards are not available, the CCR
is not used in excess quantities; and (4) if unencapsulated use of CCR involves placing over 12,400 tons
on the land in non-roadway applications, the user shall demonstrate and keep records that environmental
releases will be at or below relevant regulatory and health-based benchmarks for human and ecological
receptors in accordance with Utah Admin. Code R315-101. Use of CCR that does not comply with Utah
Admin. Code R315-319-53(8)(i)-(iv), may constitute disposal. See 40 C.F.R. § 257.50(b). Notably,
beneficial use under Utah Admin. Code R315-319-53(8)(i)-(iv) is limited to CCR and does not include
use of coal, including those minerals classified as anthracite, bituminous, subbituminous, or lignite.

Pursuant to Utah Admin. Code R315-319-53(8)(i)-(iv), the DERR concurs that any CCR found
on the Site does not require additional sampling and can be “beneficially used” at the Site. However,
this concurrence is limited to PacifiCorp’s beneficial use of less than 12,400 tons of CCR within the
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legal boundaries of the VCP Site and does not include the beneficial use of coal. If PacifiCorp intends
to place over 12,400 tons of unencapsulated CCR on the land in non-roadway applications, it shall
comply with Utah Admin. Code R315-319-53(8)(iv). The location of CCR beneficially used at the VCP
Site should be accurately recorded to ensure proper materials management, such as with a Site
Management Plan and Environmental Covenant. Additionally, if PacifiCorp chooses to beneficially use
the CCR outside the legal boundaries of the VCP Site, PacifiCorp must comply with all applicable state
and federal beneficial use requirements. Finally, if PacifiCorp chooses to dispose of CCR or transport
CCR to another PacifiCorp facility, PacifiCorp must comply with all applicable state and federal
disposal and transportation requirements.

The DERR considers the Memorandum to be specific to the Materials Management Plan (MMP)
only, which currently requires the sampling and laboratory analysis of CCR found within the VCP to
guide management and disposal strategies. If PacifiCorp intends to deviate from the MMP’s current
requirements based on the Memorandum and this Response to the Memorandum, PacifiCorp shall
submit an amendment to the MMP for DERR review and acceptance. The DERR reserves the right to
require additional sampling, testing, and management requirements if conditions at the Site or legal
requirements change.

Thank you for your participation in the VCP. If you have any questions, please contact me at
[phone].

Sincerely,

Allison Stanley, Project Manager
Division of Environmental Response and Remediation

AS/jn

cc: Orion Rodgers, Environmental Health Director, Southeastern Utah District Health Department
Jonathan Dutrow, Southeastern Utah District Health Department
Curtis Page, District Engineer, Utah Department of Environmental Quality