DSHW-2025-000730

February 10, 2025
Andrew W. Steinberg
Vice President
LE PETOMANE, Inc
35 East Wacker Dr. Suite 690, Chicago, IL 60601
RE:Approval of Vertellus Corrective Action PlanUTD009087644
Dear Mr. Steinberg:
The Division of Waste Management and Radiation Control (Division) has reviewed the Corrective Action Plan (CAP) for the former Vertellus Site (Site), dated November 26, 2024. The CAP
provides a summary of the activities that have occurred at the Site, remediation activities planned under this CAP, a completion report that will include a site human health and ecological
risk assessment (HHERA), as well as a groundwater long-term monitoring plan.
The CAP established corrective action objectives (CAOs) for the Site. These CAOs are:
Reduce the post-corrective action risk to below the threshold criteria of 1 x 10-4for carcinogens and a hazard index greater than one for noncarcinogens for all receptors.
Protect future on-site construction and industrial workers through implementation of a site management plan to mitigate risks for remaining materials ranging from 1 x 10-6 to 1 x 10-4for
carcinogens, where site management controls can be implemented to protect receptors.
Remove source materials to reduce contaminant mass, impacts to the environment, and the potential for further groundwater degradation.
To accomplish these CAOs, the CAP proposes to remove and transport and dispose of offsite 7,680 cubic yards (cy) of soil from the site. These removals are designed to target soils with
the highest concentrations of volatile organic compounds (VOCs) and polycyclic aromatic hydrocarbons (PAHs) as well as areas with visible tar derived materials (TDM). These soil removals
include:
Excavating approximately 1,222 cy down to two feet deep from Exposure Area (EA)-6 and Solid Waste Management Unit (SWMU) #7.
Excavating approximately 2,322 cy of soil to three feet deep from hot spots and visible impacts at EA-2
Excavating approximately 20 cy from hot spots and visible impacts at EA-4
Excavating approximately 2.089 cy of soil to three feet deep at EA-4 near SWMU #12.
Removing the approximately 2,000 cy that was moved during the time critical removal action (TCRA).
Removing approximately 1 cy at each of 30 surface TDM locations for a total of 30 cy.
The CAP states that the excavations are designed to be shallow to achieve the CAOs and avoid excavations into the shallow water table, which is typically encountered from 4 to 7 feet
below ground surface. Should dark staining be observed at depths below those listed in the CAP, additional limited excavations will be performed to remove the discolored soils. A flame-ionization
detector (FID) and photoionization detector (PID) will also be used to make required adjustments to excavation extents. All excavated soil will be direct loaded into trucks and sent
to Clean Harbors Grassy Mountain Landfill Facility.
Following removal of contaminated soils, the CAP states that verification samples are to be collected from the bottom of the excavation, or if the bottom of the excavation is below groundwater,
then confirmation samples will be collected from the sidewalls. The CAP calls for a total of 20 verification samples to be collected, with one sample for every 5,000 square feet of
excavation area, with a minimum of one sample per small hotspot area or three samples per larger area. Samples will be analyzed for VOCs by Environmental Protection Agency (EPA) Method
8260 and semi-volatile organic compounds (SVOCs) including PAHs by EPA Method 8270.
While the CAP states that verification samples will be collected at a maximum frequency of one sample for every 5,000 sf, the Division feels that this sample frequency should be the
minimum expected, not the maximum. Soil confirmation samples should be representative of the entire soil excavation and should indicate that the extent of the impacted soil has been
adequately addressed.
Following soil removal and verification sampling, the excavations will remain open until laboratory results are reviewed for comparison against the corrective action screening levels
in the CAP. If necessary, the excavations will be expanded until contaminant concentration necessary for the HHERA are reached. All excavations greater than six inches deep will be backfilled
using clean, imported common backfill soils.The backfilled material will be proof-rolled and mounded slightly to account for possible future settlement.
The CAP states that following completion of soil removal, site risk will be recalculated using the existing HHERA approach and data combined with the corrective action verification results
where soil excavations were performed. As discussed in the meeting on January 29, 2025, and outlined in the provided talking points for that meeting, a screening level human health and
ecological risk assessment performed in accordance with Utah Administrative Code R315-101-5 and the TGRA will be required.Since the 2013 risk assessment (DSHW-2013-003888) was not finalized
nor approved, using methodology inconsistent with current methodology will not be acceptable.An ecological screening risk assessment must be performed as the Site is currently, and portions
of it will remain a viable habitat for ecological receptors in accordance with R315-101-5(j).
Corrective action for groundwater at the Site is not part of this CAP as the Division has already indicated that monitored natural attenuation (MNA) and long-term monitoring (LTM) are
appropriate corrective actions for the impacted groundwater (DSHW-2024-007052). Included in this CAP as Appendix L is a Groundwater Long-Term Monitoring Plan (LTMP). The LTMP lists
six wells (MW-9, MW-32, MW-34, MW-10, MW-18, and MW-33) to be used for future analysis as well as six wells (MW-19, MW-33, MW-1, MW-11, PZ-4 and PZ-6) that will be gauged to aid in the
interpretation of groundwater gradient and flow direction. The wells sampled for analysis would be sampled yearly for VOCs using EPA Method 8260C and for PAHs using EPA Method 8270D
with one field duplicate for each VOCs and PAHs, one matrix spike/matrix spike duplicate for each VOCs and PAHs, one equipment blank for each VOCs and PAHs, and one trip blank for VOCs
only. Sampling will occur according to the schedule shown in Section 5.0 of the LTMP. Following completion of the fifth annual LTM event, the data will be evaluated to determine if
LTM should continue as established, or if it should be modified or terminated.
With the understanding that an HHERA will need to be completed based on requirements found in the Utah Administrative Code R315-101 and the Technical Guide for Risk Assessments, and
with the understanding that verification samples in addition to those stated in the CAP may be required, this CAP is hereby approved.
If you have any questions, please contact Jasin Olsen by email at [e-mail] or by phone at 385-499-0494.
Sincerely,
Douglas J. Hansen,Director
Division of Waste Management and Radiation Control
DJH/JO/wa
c:Eric Edwards, Health Officer, Utah County Health Department
Tyler Plewe, Deputy Director, Utah County Health Department
Jason Garrett, Environmental Health Director, Utah County Health Department

Andrew W. Steinberg, Vice President, LE PETOMANE, INC ([e-mail])
Brian Loffman, Senior Program Manager, LE PETOMANE, INC ([e-mail])