DERR-2024-011477

SITE VISIT REPORT
DATE: 09/26/2024
SITE: Former PacifiCorp Carbon Power Plant C#095
SITE ADDRESS: 75th Avenue, Helper, UT
PREPARED BY: Allison Stanley
Utah Department of Environmental Quality
Division of Environmental Response and Remediation
195 North 1950 West
Salt Lake City, UT 84116

ATTENDEES: Allison Stanley (DERR)
Bill Rees (DERR)
Boyd Breeding (AECOM)
Scott Wetzel (PacifiCorp)
Peter Brinton (PacifiCorp)
ARRIVAL TIME: 12:30 PM - DEPARTURE TIME: 3:30 PM
Is the work being performed in a manner consistent with the accepted workplan? NA
SUMMARY:
DERR arrived on-site at 12:30 PM and met with Boyd, Scott, and Peter. A safety briefing was
conducted before walking the site. For the site visit, we walked through four of the areas of the
site: the former coal storage area (FCS), power house (PH), coal storage area (CS), and the waste
water ponds (WWP). The site is located just off Highway 6 and Highway 191 near Helper, Utah.
The Site is located in a canyon with no nearby neighbors and little exposure. Tracks from the
Union Pacific Rail Road (UPRR) run along the south of the VCP site near the CS and WWP
areas.
The FCS berm is approximately 10-15 feet high and follows the Willow Creek. Lithological logs
show that this berm contains residual coal that was likely pushed up, along with rocks and other
vegetation, near the time of the development of the plant. At the time of the visit, the creek had
very little to no water. While walking the creek, larger boulders were found along the side of the
berm defining the path of the stream. While walking the creek, attempts were made to try and
estimate the height of streamflow and very fine sand, likely from deposition, was found along the
bank a few feet up from the bottom of the creek. It is believed that this berm was created to help
contain flood waters from the Willow Creek from entering the FCS area and/or keeping runoff
that may have passed through any coal in the FCS area from entering the creek.
The PH area is fenced off with a locked gate for access. We discussed the foundations, which are
still in place and covered with a few feet of fill. Soil samples from 2019 were sampled beneath
the concrete slab where the building used to stand.
The CS area is an open field with some vegetation. Monitoring well CS-1 was located and is
intact. This well marks the location for the underground storage tank (UST) which received a No
Further Action Letter dated January 23, 1998, and is currently managed by the DERR leaking
underground storage tank (LUST) program. The UST is not part of the VCP. A wooden stake,
believed to mark the location of CS-UPRR33, identifies the location for the commercial
exceedance of lead in soil. Peter and Scott identified that this area is leased by PacifiCorp from
UPRR, who are not applicants under the VCP. Both the DERR and PacifiCorp are working to
come to a solution for this lease area.
The entrance to the WWP area is fenced off with a gate. Before the VCP, up to five feet of coal
combustion materials were excavated from the bottom of the ponds and backfilled with concrete
and approximately 2 feet of fill. The decision to leave the WWP berm in place was made by
PacifiCorp in consultation with the United States Army Corps of Engineers as it helps control the
Price River during flood stages. Lithological logs show that approximately 6-8 feet of the berm
contain coal ash. During the visit, it was unknown the exact point where the coal ash in the
berms starts. The berm is located along a flat stretch of the river with no major curvature of the
river that would heavily increase erosion to the berms. The berm is relatively steep with some
larger boulders and vegetation. At one point along the berm, it appears that there was some
overhang as the river has cut underneath. The WWP berms that do not border the Price River
have been removed, except for a small portion of a berm located between the two ponds. This
section of the berm was exposed with possible coal ash.
Other items that were discussed during the visit include some asbestos-cement transite piping
still present at the site. This piping is buried and the locations are mapped. Higher levels of
arsenic in soil at the site was also discussed. Additionally, PacifiCorp informed the DERR that
Helper City has plans to install a water line this fall that would run through the VCP site. The
DERR asked PacifiCorp to involve the DERR with this process. PacifiCorp and AECOM are
currently working on a remedial action plan (RAP) and a materials management plan (MMP) for
the site.

PHOTO LOG:

Photo 1: Looking north-east along Highway 191. FCS berm to the left and Power House to the
right (out of the picture).

Photo 2: Area of the former Power House.

Photo 3: View of Willow Creek looking west. Little to no water was present in the creek at the
time of the site visit.

Photo 4: Larger boulders found along the inside berm of Willow Creek.

Photo 5: Very fine-grained sand located on the bank in the Willow Creek, a few feet above the
lowest point of the creek bed.

Photo 6: The Coal Storage area consists of a field with some vegetation. The site is located in the
Price Canyon with no nearby neighbors for exposure.

Photo 7: Monitoring well CS-1 located near the UST managed under the DERR LUST program.

Photo 8: Wooden stake in the CS area to indicate the location of CS-UPRR33 where there is a
commercial RSL exceedance of lead in soil.

Photo 9: Bend of the Price River in the WWP area (looking from the bridge). Further down the
river when it straightens out is where the confirmed coal ash berm is located.

Photo 10: The Price River flows beneath the bridge which marks the entrance to the WWP area.
In the upper right-hand corner of the image, there is a sharp turn of the river which is marked by
a concrete wall. The speed of flow was observed to be higher in this section than the stretch
along the WWP berm.

Photo 11: The Price River looking east. The WWP berm is located to the right along a relatively
straight section of the river. Just before the river starts to curve again marks the end of the berm.

Photo 12: Looking directly at the WWP berm. The incline is steep with some vegetation and
larger rocks/boulders.

Photo 13: Looking at area of WWP berm where the water has started to erode underneath the
berm to create a small overhang.

Photo 14: Exposed berm between the two ponds in the WWP area. This is believed to be coal ash
but there is no lithological data for this location.

Photo 15: View of the second former waste water pond.