DERR-2024-010790

VCP/Brownfields Section - Site Visit Report

SITE NAME: Mayflower Mine

SITE LOCATION: Wasatch County

DATE OF SITE VISIT: 12 September 2024

PURPOSE OF SITE VISIT: DERR (David Bird) oversight of Phase 1 remedial action.

FIELD OBSERVATIONS: The DERR visited the Mayflower VCP site at ~10:45 am on 12 September to
meet with Extell personnel and their contractors and observe conditions at the site. The DERR met
with Extell (Kent Fawcett). Current progress of the work to address subsidence on the western portion
of the Repository and the moving of the stormwater detention pond further upstream in the Big Dutch
Pete Hollow (BDPH) drainage were discussed, as was a meeting between the parties to discuss
finalization of the Remedial Action Report for the site along with the accompanying Site Management
Plan and Environmental Covenant.
The DERR walked to the western end of the Repository to examine work being done for the subsidence
there. Roadbase type material was placed there to bring this area up to grade in preparation for the
replacement asphalt cap/parking lot surface. Extell has done the majority of the grading for the
stormwater detention pond moved ~100 yards up the BDPH drainage and away from the repository.
Excavation work for the piping and spillway is next. This is expected to be complete in about 3 weeks.
The DERR left the site at ~11:55 am.
SPLIT SAMPLES COLLECTED: N/A

IS THE WORK BEING PERFORMED IN A MANNER CONSISTENT WITH THE ACCEPTED WORKPLAN?
Yes

Looking south at the western end of the Repository where the grade is being raised because of
subsidence.