DERR-2024-004957

REMEDIAL ALTERNATIVES EVALUATION
Lelis Transmissions
845 South Main Street
Salt Lake City, Utah
EPA Cooperative Agreement # 96896101
EPA ACRES Property ID # 273101
July 20, 2020
Terracon Project No. 61197491 Task 19
Prepared for:
Salt Lake County
Salt Lake County, Utah
Prepared by:
Terracon Consultants, Inc.
Salt Lake City, Utah
Terracon Consultants, Inc. 6949 So. High Tech Drive Midvale, Utah 84047
P [phone] F [phone] terracon.com
July 20, 2020
Salt Lake County
2001 S. State St., Suite S2-100
P.O. Box 144575
Salt Lake City, Utah 84114-4575
Attn: Mr. Ruedigar Matthes
P: [phone]
E:[e-mail]
Re: Remedial Alternatives Evaluation
Lelis Transmissions
845 South Main Street
Salt Lake City, Utah
Terracon Project No. 61197491 Task 19
EPA Cooperative Agreement #96896101
EPA ACRES Property ID# 237101
Dear Mr. Matthes:
Terracon Consultants, Inc. (Terracon) presents to Salt Lake County this Remedial Alternatives
Evaluation for the above-referenced Site. This document is intended as a brief preliminary
document summarizing known environmental impacts and remedial alternatives based on Site-
specific conditions, technical feasibility and preliminary cost/benefit analyses. Specific cleanup
alternatives and associated recommendations are presented in the applicable sections of this
report.
Terracon appreciates this opportunity to continue to provide environmental consulting services
for Salt Lake County in support of Brownfields redevelopment. Should you have any questions or
require additional information, please do not hesitate to contact our office at [phone].
Sincerely,
Terracon Consultants, Inc.
Andy R. King Benjamin B. Bowers
Senior Project Manager Environmental Department Manager
Responsive ■Resourceful ■Reliable i
TABLE OF CONTENTS
1.0 INTRODUCTION AND BACKGROUND...................................................................................... 1
1.1 Summary of Identified Impacts to Soil, Groundwater, and Soil Gas ................................. 2
1.2 Project Goal ................................................................................................................... 5
2.0 APPLICABLE REGULATIONS AND CLEANUP STANDARDS .................................................. 5
2.1 Cleanup Oversight Responsibility ................................................................................... 5
2.2 Cleanup Standards ......................................................................................................... 6
2.3 Laws & Regulations Applicable to Cleanup Activities ...................................................... 6
3.0 REMEDIAL ALTERNATIVES EVALUATION .............................................................................. 7
3.1 Cleanup Objectives ........................................................................................................ 7
3.2 Cleanup Alternatives Considered .................................................................................... 9
3.2.1 Alternative 1: No Action .................................................................................... 10
3.2.2 Alternative 2: Remove Contaminant Source Structures .................................... 10
3.2.3 Alternative 3: Mobile Dual-Phase Extraction (MDPE) ........................................ 11
3.2.4 Alternative 4: Remove Impacted Soils ............................................................. 11
3.2.5 Alternative 5: TPH Fractionation and Development of SSCLs .......................... 12
3.3 Recommended Cleanup Alternative .............................................................................. 13
4.0 REFERENCES ......................................................................................................................... 14
APPENDICES
APPENDIX A – Exhibits
Exhibit 1 – Topographic Map
Exhibit 2 – Site Diagram
Exhibit 3 – Soil and Groundwater Sampling Points
Exhibit 4 – Soil Gas Sampling Points
Exhibit 5 – Soil Sample Results
Exhibit 6 – Groundwater Sample Results
Exhibit 7 – Groundwater Gradient Map
APPENDIX B – Tables
Table 1 – Brownfield Cleanup Alternatives Balancing Factor Evaluation
Table 2 – Estimated Comparative Costs for Cleanup Alternatives
Responsive ■Resourceful ■Reliable 1
1.0 INTRODUCTION AND BACKGROUND
The site is located at 845 South Main Street, Salt Lake City, Utah and is occupied by the Lelis
Transmissions shop (Exhibits 1 and 2, Appendix A). The property is used as an auto repair facility.
Commercial improvements at the site include an L-shaped 1-story building with mezzanine and
approximately 7,400 square-foot automotive service/repair facility. The office/warehouse was
used for storage of automotive parts and reference materials, the eastern part of the building is
used for conducting automotive repair.
Terracon had previously conducted a Limited Site Investigation (LSI) on the site in 2015 to
evaluate the source of diesel contamination reported on the south-adjoining property. Soil and
groundwater samples were collected in the vicinity of the former gasoline underground storage
tank (UST) that was removed from the Lelis Transmissions site in 1991. Diesel-range and
gasoline-range petroleum hydrocarbons were reported on the Lelis site, but at concentrations less
than those reported present on the south-adjoining property. The observed distribution and type
of contaminant reported on the Lelis site was determined to likely have originated from an off-site
source.
In 2019, Terracon conducted a Phase I Environmental Site Assessment (ESA) on the site as part
of the Salt Lake County Brownfields Assessment Grant (Terracon, July 25, 2019). The Phase I
ESA was compliant with Brownfields All Appropriate Inquiry and was performed in conformance
with the scope and limitations of American Society for Testing and Materials (ASTM) Practice
E1527-13 for the parcel located at 845 South Main Street in Salt Lake City, Salt Lake County,
Utah. The purpose of the Phase I ESA was to identify Recognized Environmental Conditions
(RECs) in connection with the site at the time of the reconnaissance. The following RECs were
identified in connection with the site:
n Long term use as auto repair:The facility has operated as an auto repair shop since the
mid to late-1940s. The historic use of in-ground lifts, long-term chemical use associated
with automotive repair, floor drains and sump, and an oil/water separator tied to a possible
French drain were identified as a REC to the site.
n Historical USTs: According to a historical research, there was one former gasoline UST
on the site. During a previous subsurface investigation conducted by Terracon for the
property owner, contaminated groundwater and soil were encountered but believed to
originate from an off-site source. The release from the off-site source that has impacted
the site was identified as a REC.
n Former Nearby Dry-Cleaning Operations: The potential for historical releases from dry
cleaning operations previously conducted in a facility located to the north, in a presumed
up-gradient location, was considered a REC for the site.
Remedial Alternatives Evaluation
Lelis Transmissions ■ 845 South Main Street, Salt Lake City, Utah
ACRES ID#237101 ■ Terracon Project 61197491 ■July 20, 2020
Responsive ■Resourceful ■Reliable 2
Terracon subsequently completed a Phase II Environmental Site Assessment to assess potential
soil and groundwater impacts originating from the identified RECs. The Phase II ESA (Terracon,
September 30, 2019) was completed with funding from the Salt Lake County Brownfields
Assessment Grant, in accordance with an approved site-specific Sampling and Analysis Plan and
Quality Assurance Project Plan.
The Phase II ESA scope of work included advancement of 16 investigation borings for collection
of soil and groundwater samples near the following features of concern.
n eight hydraulic lift hoists,
n one used-oil aboveground storage tank (AST);
n five interior floor drains;
n one interior sump;
n one exterior drain;
n one oil/water separator; and
n in the southeastern and south-central portions of the site to evaluate potential
impacts from the south-adjoining property.
Four sub-slab soil gas sampling points were also installed inside the building to allow for the
collection of soil gas samples to assess the potential for vapor intrusion.
The Phase II ESA also included the completion of four of the borings as temporary piezometers
to allow evaluation of the local groundwater flow conditions. Based on groundwater elevation
measurements from the piezometers, the groundwater flow direction is to the northwest.
Exhibits 3 through 7 (Appendix A) from the Phase II ESA show the locations of key site features
and sampling locations, and convey pertinent information including sampling results and
groundwater flow direction.
1.1 Summary of Identified Impacts to Soil, Groundwater, and Soil Gas
Laboratory analyses of soil and groundwater samples included volatile organic compounds
(VOCs); total recoverable petroleum hydrocarbons (TRPH); total petroleum hydrocarbons -diesel
range organics (TPH-DRO), total petroleum hydrocarbons-gasoline range organics (TPH-GRO),
and metals. Laboratory analyses of soil gas samples were focused on VOCs.
Constituent concentrations in soils were compared to current EPA Regional Screening Levels
(RSLs) for residential and industrial use scenarios, and to Utah Department of Environmental
Quality (UDEQ) Leaking Underground Storage Tank (LUST) Initial Screening Levels (ISLs) and
Tier 1 Screening Levels.
Remedial Alternatives Evaluation
Lelis Transmissions ■ 845 South Main Street, Salt Lake City, Utah
ACRES ID#237101 ■ Terracon Project 61197491 ■July 20, 2020
Responsive ■Resourceful ■Reliable 3
Constituent concentrations in groundwater were compared to EPA Maximum Contaminant Levels
(MCLs), UDEQ-LUST ISLs and Tier 1 Screening Levels, Utah Ground Water Quality Protection
Standards (UGWQPS; UAC-R317-6-2.1), and EPA Vapor Intrusion Screening Levels (VISLs) for
residential and industrial use (with target cancer risk of 1X10-6 and target hazard quotient of 1).
Constituent concentrations in soil gas were compared to EPA VISLs for residential and industrial
use (with target cancer risk of 1X10-6 and target hazard quotient of 1).
Soil Impacts
n Widespread soil impacts were identified by petroleum hydrocarbons, primarily in
the form of TRPH and TPH-DRO. A localized occurrence of TPH-GRO was also
identified during the 2015 LSI.
o A total of eight soil sampling locations identified TRPH concentrations
exceeding the ISL of 1,000 milligrams per kilogram (mg/kg), and four
sampling locations identified TRPH concentrations above the Tier 1
Screening Level of 10,000 mg/kg.
o A total of nine soil sampling locations identified TPH-DRO concentrations
exceeding the ISL of 500 mg/kg, and three sampling locations identified
TPH-DRO concentrations above the Tier 1 Screening Level of 5,000
mg/kg.
o Three soil sampling locations identified TPH-GRO concentrations above
the ISL of 150 mg/kg; each location was adjacent to the former onsite
gasoline UST.
o None of the soil samples identified individual Utah-regulated petroleum
hydrocarbon compounds [benzene, toluene, ethylbenzene, toluene,
naphthalene (BTEXN) and methyl-tert-butyl ether (MTBE)] at
concentrations above ISLs or Tier 1 Screening Levels. One soil sample
reported a naphthalene concentration above the residential RSL of 3.8
mg/kg, but below the industrial RSL of 17 mg/kg and below the ISL and
Tier 1 Screening Level of 51 mg/kg.
n Soil impacts by VOCs were not identified, other than one soil sample with a
reported naphthalene concentration above the residential RSL but below all other
screening levels.
n A total of ten (10) soil samples collected from five (5) soil borings were analyzed
for the 13 Priority Pollutant Metals. All soil samples reported arsenic
concentrations above the EPA Industrial RSL. However, such exceedances are
common throughout the Salt Lake Valley area where background values
reportedly range from non-detect to 97 mg/kg (U.S. Geological Survey
Professional Paper 1270; 1984). The arsenic concentrations reported in site soil
samples ranged from 4.02 to 41.1 mg/kg. Based on these results, the reported
Remedial Alternatives Evaluation
Lelis Transmissions ■ 845 South Main Street, Salt Lake City, Utah
ACRES ID#237101 ■ Terracon Project 61197491 ■July 20, 2020
Responsive ■Resourceful ■Reliable 4
arsenic concentrations in soil appear to be representative of natural background
levels.
n The concentration of lead reported at one soil boring (LT-B-15, near the oil/water
separator) exceeded the EPA Industrial RSL. This same boring also reported the
above-referenced naphthalene exceedance of the residential RSL.
Groundwater Impacts
n Free product was observed within the soil profile at two boring locations in the
eastern and central portions of the site. The observed product exhibited a viscous
oily appearance and did not appear to be associated with diesel fuel or gasoline.
n Widespread groundwater impacts were identified by petroleum hydrocarbons,
primarily in the form of TRPH and TPH-DRO. A localized occurrence of TPH-
GRO was also identified during the 2015 LSI.
o Two groundwater sampling locations identified TRPH concentrations
exceeding the Tier 1 Screening Level of 10 milligrams per liter (mg/l).
o A total of three groundwater sampling locations identified TPH-DRO
concentrations exceeding the ISL of 1 mg/l, and four sampling locations
identified TPH-DRO concentrations above the Tier 1 Screening Level of
10 mg/l.
o One groundwater sampling location identified a TPH-GRO concentration
above the ISL of 1 mg/l, adjacent to the former onsite gasoline UST.
o None of the groundwater samples identified any BTEXN or MTBE
constituent concentrations above ISLs or Tier 1 Screening Levels.
n Groundwater impacts by VOCs were not identified above screening levels, other
than two samples that reported concentrations of a VOC that were higher than
the corresponding groundwater VISL.
n Two groundwater samples identified dissolved arsenic at a concentration above
the MCL, and one of these also exceeded the UGWPS.
Soil Gas
Sub-slab soil gas sample points were installed four locations throughout the site. Multiple VOCs
were detected at concentrations above the laboratory method detection limits, but at
concentrations below the corresponding residential and commercial VISLs. Although two of the
groundwater samples reported concentrations of a VOC that were than the corresponding
groundwater VISL, the sub-slab soil vapor sample results did not indicate a potential vapor
intrusion issue.
Remedial Alternatives Evaluation
Lelis Transmissions ■ 845 South Main Street, Salt Lake City, Utah
ACRES ID#237101 ■ Terracon Project 61197491 ■July 20, 2020
Responsive ■Resourceful ■Reliable 5
1.2 Project Goal
This Remedial Alternatives Evaluation has been prepared to support redevelopment of the site
by prospective developers by providing preliminary cleanup planning information. It is Terracon’s
understanding that the current owner seeks to perform sufficient cleanup to sell the property for
redevelopment while retaining the existing buildings. The buildings would incorporated into a
future re-development for commercial/industrial use and could potentially include residential use.
2.0 APPLICABLE REGULATIONS AND CLEANUP STANDARDS
2.1 Cleanup Oversight Responsibility
Terracon believes the most appropriate regulatory programs to oversee remediation of the Site
within the Utah DEQ are 1) the Division of Environmental Response and Remediation (DERR) –
Leaking Underground Storage Tank (LUST) Program, or 2) the DERR - Voluntary Cleanup
Program (VCP). Either program may require further investigation to more fully delineate the
extent of impacts. Either program may be appropriate if cleanup is funded privately, but the VCP
would likely be required if Brownfield funds were to be used.
The DERR - LUST program currently includes a listing of the site with an open LUST release case
file. The release (case file GTS) was previously granted “no further action” (NFA) status in 1996
with the following qualification:The information you have submitted indicates that petroleum
contamination remaining at the site complies with state underground storage tank rules. Based
upon current land use, there appears to be no pathway for exposure to the contamination. In the
future, if there is a change in land usage, or if other evidence indicates a spread of contamination
from the facility which may cause a threat to human health or the environment, further corrective
action may be required. The case file for this release was re-opened, however, in April 2015
following the discovery of petroleum contamination beneath the south-adjoining property.
Terracon’s 2015 LSI was conducted in response to the re-opening of the release case file, which
required further investigation in the vicinity of the former onsite gasoline UST. Closure of the
LUST case file and reinstatement of NFA status will likely require removal of the free product,
along with cleanup to ISLs 1 Screening Levels (or to site-specific cleanup levels) and/or
demonstration that no exposure pathways are complete with contamination remaining in place.
Under the DERR - VCP Program, a Certificate of Completion would be issued following cleanup
to agency-specified levels (likely RSLs and ISLs or alternate site-specific cleanup levels) with
VCP oversight. Once issued, the VCP Certificate of Completion provides a limited release of
liability to qualified applicants as specified in the statute, and the liability release is transferable to
subsequent property owners.
Remedial Alternatives Evaluation
Lelis Transmissions ■ 845 South Main Street, Salt Lake City, Utah
ACRES ID#237101 ■ Terracon Project 61197491 ■July 20, 2020
Responsive ■Resourceful ■Reliable 6
All work plans, including sampling and analysis plans and quality assurance project plans, and
reports related to environmental investigations and remediation activities conducted at the Site
will be submitted to the selected agency for review and approval.
2.2 Cleanup Standards
Terracon understand that the property will be re-developed for commercial use with the possibility
of residential development. With this anticipated exposure scenario, Terracon anticipates the
following screening levels will be used as the Cleanup Standards for the Site.
n Soil: For petroleum products, Utah DEQ’s ISLs and Tier 1 Screening Levels or
site-specific risk-based standards in accordance with the DERR - LUST program.
For non-petroleum contaminants, EPA’s most recent RSLs for residential soil with
a target cancer risk of 1x10-6 and a hazard quotient of 1.
n Groundwater: For petroleum products, Utah DEQ’s ISLs and Tier 1 Screening
Levels or site-specific risk-based standards in accordance with the DERR - LUST
program. For non-petroleum contaminants, EPA’s most recent Maximum
Contaminant Levels (MCLs) for drinking water or EPA’s most recent Target
Groundwater Concentration Vapor Intrusion Screening Levels for residential
exposure scenarios with a target cancer risk of 1x10-6 and a hazard quotient of
1.
n Soil Vapor: EPA’s most recent Target Sub-slab and Near-source Soil Gas
Concentration Vapor Intrusion Screening Levels for residential exposure
scenarios with a target cancer risk of 1x10-6 and a hazard quotient of 1.
2.3 Laws & Regulations Applicable to Cleanup Activities
Laws and regulations that are applicable to cleanup activities include:
n Occupational Safety and Health Act, Hazardous Waste Operations and
Emergency Response Standard (40CFR1910.120) and applicable Safety and
Health Regulations for Construction (29CFR1926).
n National Emissions Standards for Hazardous Air Pollutants (NESHAP) (40CFR61
– Subpart M: National Emission Standard for Asbestos).
n Department of Transportation, Hazardous Materials Regulations (49CFR Subtitle
B, Chapter 1, Subchapter C).
n Resource Conservation and Recovery Act (42 U.S.C. § 6901, et. seq.).
n National Historic Preservation Act of 1966, Section 106.
n Utah Code Ann. 19-6-401 et. seq. (Underground Storage Tank Act and rules
promulgated there under (Utah Admin Code, R311)) and the Corrective Action
Remedial Alternatives Evaluation
Lelis Transmissions ■ 845 South Main Street, Salt Lake City, Utah
ACRES ID#237101 ■ Terracon Project 61197491 ■July 20, 2020
Responsive ■Resourceful ■Reliable 7
Cleanup Standards Policy Per UST and CERCLA Acts, Utah Admin. Code, R311-
211.
n Utah Code Ann. 19-6-101 et. seq. (Solid and Hazardous Waste Act and rules
promulgated there under (Utah Admin Code, R315)).
n Utah Code Ann. 19-5-101 et. seq. (Water Quality Act and rules promulgated there
under (Utah Admin Code, R317)).
n Utah Code Ann. 19-2-101 et. seq. (Air Conservation Act and rules promulgated
there under (Utah Admin Code, R307)).
n Utah Code Ann. 57-25-101 et. seq. (Uniform Environmental Covenants Act).
n Salt Lake City, Salt Lake County, and State building codes and construction
requirements.
n Utah Code Ann. Title 19, Chapter 6, Part 3 et seq. (Hazardous Substances
Mitigation Act).
n Utah Code Ann. Title 19, Chapter 8 et seq. (Voluntary Cleanup Program), if the
Site cleanup is conducted under the VCP.
n Federal Small Business Liability Relief and Brownfields Revitalization Act, if
Brownfields or other Federal funding is used.
n Federal Davis-Bacon Act, if Brownfields or other Federal funding is used.
In addition, all appropriate permits and notifications (e.g., Blue Stakes of Utah Utility Notification
Center, soil disposal acceptance notification, soil transport/disposal manifests, etc.) will be
obtained as appropriate for the type(s) of cleanup activities implemented.
3.0 REMEDIAL ALTERNATIVES EVALUATION
A discussion of the cleanup objectives and an evaluation of remedial alternatives for the Site are
provided below.
3.1 Cleanup Objectives
n Free product was observed within the soil profile at two boring locations in the
eastern and central portions of the site. The observed product exhibited a viscous
oily appearance and did not appear to be associated with diesel fuel or gasoline.
Removal of the free product would be a primary remedial goal to eliminate an
ongoing source of impact to groundwater.
n Petroleum-related TRPH and TPH-DRO have been identified in groundwater
samples at concentrations above DERR Tier 1 Screening Levels and/or ISLs, with
groundwater typically encountered at depths ranging from approximately 8 to 14
feet. However, the same groundwater samples did not report elevated
Remedial Alternatives Evaluation
Lelis Transmissions ■ 845 South Main Street, Salt Lake City, Utah
ACRES ID#237101 ■ Terracon Project 61197491 ■July 20, 2020
Responsive ■Resourceful ■Reliable 8
concentrations of individual regulated BTEXN or MTBE petroleum constituent
compounds or other VOCs. A remedial goal would be to manage, reduce or
eliminate exposure potential to the TRPH and TPH-DRO in groundwater.
n Petroleum-related TRPH and TPH-DRO have been identified in soil samples
throughout much of the site at concentrations above DERR Tier 1 Screening
Levels and/or ISLs, at depths ranging from approximately 7.5 to 10 feet. A
localized area with ISL exceedances for TPH-GRO in soil was also identified
onsite in the area of the former UST basin in a previous (2015) investigation.
However, the same soil samples did not report elevated concentrations of
individual regulated BTEXN or MTBE petroleum constituent compounds or other
VOCs. A remedial goal would be to manage, reduce, or eliminate exposure
potential to the TRPH, TPH-DRO, and TPH-GRO in soils.
n An elevated lead concentration (exceeding the EPA industrial RSL) was reported
from one soil sample collected at a depth of 10 feet in the central portion of the
site (beneath pavement). A remedial goal would be to manage, reduce, or
eliminate exposure potential to the lead in soils.
n Sub-slab soil vapor samples collected from four locations throughout the site
identified low levels of multiple VOCs at concentrations above the laboratory
reporting limits, but well below the corresponding residential and commercial
VISLs. Although two of the groundwater samples reported concentrations of a
VOC that were higher than the corresponding groundwater VISL, the sub-slab soil
vapor sample results did not indicate VISL exceedances or a corresponding
potential vapor intrusion issue.
The primary conditions driving a need for cleanup are petroleum impacts including the presence
of free product, which requires removal, and elevated concentrations of TPH-DRO and TRPH in
soil and groundwater. Petroleum-impacts to soil and groundwater are typically assessed in terms
of individual compounds including benzene, toluene, ethylbenzene, xylenes and naphthalene
(BTEXN) and methyl-tert-butyl ether (MTBE), along with TPH-DRO, TPH-GRO, and TRPH
(collectively, “TPH”). Risk-based assessment of TPH in soil and groundwater is well established,
as BTEXN and MTBE comprise a small fraction of the numerous other non-specific aliphatic and
aromatic compounds that make up the majority of petroleum constituents that are collectively
quantified and reported as “TPH.”
The UDEQ – DERR employs a risk-based corrective action (RBCA) process with generic risk-
based screening levels (RBSLs) that include ISLs and Tier 1 Screening Levels. The DERR’s
RBCA process also includes an option for development of non-generic, site-specific cleanup
levels (SSCLs). For TPH, the DERR’s RBCA process for development of SSCLS includes use of
a fractionation process that generally involves resolving TPH petroleum-based constituents into
specific fractions or mass ranges based on similar chemical and physical fate and transport
characteristics, and then assigning representative toxicity criteria to each fraction by using a
specific chemical surrogate. TPH fractionation analyses have not been conducted on soil or
Remedial Alternatives Evaluation
Lelis Transmissions ■ 845 South Main Street, Salt Lake City, Utah
ACRES ID#237101 ■ Terracon Project 61197491 ■July 20, 2020
Responsive ■Resourceful ■Reliable 9
groundwater samples from the Lelis Site, but TPH fractionation was previously conducted on
several groundwater samples from the northern portion of the south-adjoining property, where the
overall groundwater impacts are chemically similar to those observed at the Lelis site. Review of
results from the previous TPH fractionation analyses suggest that for the Lelis site, SSCLs for
most or all TPH fractions may already be met, in which case the need to remediate TPH would
be reduced or eliminated. Collection of additional soil and groundwater samples from the Lelis
site, with analyses for TPH fractionation, would be necessary to assess whether SSCLs are met.
3.2 Cleanup Alternatives Considered
Terracon has discussed proposed redevelopment scenarios with the property owner and has
incorporated information from those conversations into this Remedial Alternatives Evaluation.
The assumptions behind the consideration of cleanup alternatives include the following.
n The owner intends to perform sufficient cleanup to sell the property for
redevelopment while retaining the existing buildings.
n The Site will be redeveloped for commercial/industrial use and could potentially
incorporate residential development in the future. The current buildings will
remain in place and be incorporated into a future re-development.
n At a minimum, site cleanup will require removal of free product, along with
removal of the apparent on-site contaminant sources including lift hoists, floor
drains, a sump, and a waste-oil AST.
n Impacts to onsite groundwater at concentrations above regulatory screening
levels are limited primarily to TPH-DRO and TRPH. Similar levels of TPH-DRO
also exist in groundwater beneath the south-adjoining (upgradient) property,
where previous land uses appear to have contributed to the local groundwater
impacts. Onsite groundwater is also locally impacted by arsenic, which was
identified at concentrations above regulatory screening levels at two onsite
borings.
n It is unknown whether the identified impacts in groundwater extend offsite to the
north and west (downgradient) of the site, and additional investigative efforts may
be required to determine if such off-site impacts have occurred.
n Impacts to onsite soils at concentrations above regulatory screening levels are
limited to TPH-DRO and TRPH, along with a localized occurrence of TPH-GRO
and a localized occurrence of lead. All of these soil impacts were identified at
depths ranging from 7.5 feet to 10 feet.
n The generic screening level exceedances for TPH (including TPH-DRO and
TRPH) can be addressed through development of non-generic SSCLs following
additional analyses for TPH fractionation and semivolatile organic compounds
(SVOCs).
Remedial Alternatives Evaluation
Lelis Transmissions ■ 845 South Main Street, Salt Lake City, Utah
ACRES ID#237101 ■ Terracon Project 61197491 ■July 20, 2020
Responsive ■Resourceful ■Reliable 10
n Vapor mitigation is not needed based on the results of sub-slab vapor sampling
and the nature of the impacts to soil and groundwater.
n An Environmental Covenant will likely need to be recorded on the title of the
property to place institutional controls on the property. The Environmental
Covenant will likely restrict groundwater uses (i.e., no use of groundwater) and
may incorporate additional measures to address potential exposure to the
contaminants in subsurface soils.
n This evaluation does not consider the potential presence of asbestos-containing
materials (ACM) or hazardous materials such as mercury-containing thermostats
and fluorescent light fixtures; PCB-containing light fixture ballasts or transformers;
refrigeration units containing chlorofluorocarbons; containers of liquid or
hazardous substances; vehicle batteries and tires, etc. The potential presence of
these types of materials would need to be assessed prior to structure renovation
or potential removal as part of future redevelopment, via a Building Material
Survey to assess whether the site structures contain ACM and/or hazardous
materials that may require abatement or specialized management.
Five cleanup alternatives are outlined below, and Table 1 provides a comparative evaluation of
these alternatives with respect to effectiveness, long-term reliability, implementability, and relative
costs. The final solution may involve a combination of multiple alternatives to achieve project
goals. More detailed comparison of potential implementation costs is provided in Table 2. The
tables can be found attached to this report in Appendix A.
3.2.1 Alternative 1: No Action
The No Action alternative is included as a baseline comparison to other remedial alternatives and
assumes no action is taken.
3.2.2 Alternative 2: Remove Contaminant Source Structures
This alternative is a stand-alone action to remove ongoing sources of impact to subsurface soils
and groundwater. This alternative would generally include the following components:
n Remove (eight) existing hydraulic lift hoists from the site
n Remove existing used-oil AST
n Remove existing sump
n Remove existing oil/water separator
n Remove existing floor drains (five interior, one exterior)
The removed items and their contents would be disposed offsite at an appropriately-permitted
facility. If any of the materials are characterized as a RCRA regulated hazardous waste, the
Remedial Alternatives Evaluation
Lelis Transmissions ■ 845 South Main Street, Salt Lake City, Utah
ACRES ID#237101 ■ Terracon Project 61197491 ■July 20, 2020
Responsive ■Resourceful ■Reliable 11
wastes will be segregated, and the hazardous waste portions would be sent to an approved
hazardous waste disposal facility. For the purpose of this evaluation, it is assumed that all
removed materials can be disposed of as a non-hazardous waste. In addition, a cleanup
completion report would be prepared to document the cleanup activities, and the final condition
of the site following the removal action. This alternative does not include removal of impacted
soils or groundwater.
3.2.3 Alternative 3: Mobile Dual-Phase Extraction (MDPE)
This alternative involves using high-vacuum equipment to remove free product, where present at
the site, and petroleum-impacted groundwater along with vapor-phase hydrocarbons. With a
large-scale application of this option, a series of approximately 12 temporary extraction wells
would be installed throughout the eastern and central portions of the site, including the eastern
building and the central open area. The MDPE vacuum extraction equipment would be connected
to the extraction wells for simultaneous extraction of free product (where present) and
groundwater, along with vapor-phase hydrocarbons. Extracted vapors would be treated by
carbon adsorption through the use of carbon canisters, while the extracted liquids would be
transferred to a holding tank, from which the free product would be removed for offsite disposal.
The extracted groundwater would be pre-treated within the holding tank by sparging, followed by
discharge to the sanitary sewer system. Under this large-scale MDPE scenario, the MDPE
equipment would be staged for operation at the site for a period of approximately 30 days. Pre-
approval is required to discharge the treated water to the sanitary sewer system, and pre-
discharge sampling would be required to confirm compliance with discharge standards. However,
obtaining approval to discharge treated water to the Salt Lake City sewer system can be
problematic due to the City’s discharge policies, and other (more costly) means for disposal of
treated water may become necessary.
A smaller-scale MDPE application may also be used to focus primarily on removal of free product.
In this scenario, approximately four temporary extraction wells would be installed at and between
the two locations where free product was observed. A vacuum truck would be used to extract the
free product from these wells, along with impacted groundwater and hydrocarbon vapors. The
extracted liquids would be disposed offsite at an appropriately-permitted facility. Extracted vapors
would be discharged to the atmosphere, following notification and approval by the Utah Division
of Air Quality. Under this small-scale MDPE application scenario, the MDPE vacuum truck would
operate onsite for a single day, after which the extraction wells would be monitored for potential
return of free product. If necessary, one or more additional MDPE vacuum-extraction events
could be conducted until it is confirmed that no free product returns.
3.2.4 Alternative 4: Remove Impacted Soils
Alternative 4 targets the subsurface petroleum-impacted soils throughout the site, along with the
localized soils that contain elevated lead concentrations. Soils with exceedances of Tier 1
Screening Levels and/or ISLs for non-specific petroleum constituents (TRPH and TPH-DRO)
Remedial Alternatives Evaluation
Lelis Transmissions ■ 845 South Main Street, Salt Lake City, Utah
ACRES ID#237101 ■ Terracon Project 61197491 ■July 20, 2020
Responsive ■Resourceful ■Reliable 12
have been identified throughout much of the site including beneath the eastern building and the
central open area, with localized ISL exceedances of TPH-GRO near the former onsite gasoline
UST basin. The affected area also includes locally elevated lead concentrations near the oil/water
separator. The impacted soils were identified at depths ranging from 7.5 to 10 feet below grade.
Removal of impacted soils would require removal of existing concrete, asphalt, and non-impacted
overburden soils prior to excavation of the impacted soils at depth. This alternative would
generally include the following components:
n Remove existing concrete and asphalt surfaces including interior building floor
slabs, transport offsite for disposal as construction debris;
n Excavate approximately 8 feet of non-impacted overburden soils, transport offsite
for disposal or potential re-use offsite;
n Excavate petroleum-impacted soils and lead-impacted soils within an estimated
average depth range of 8 to 10 feet, transport offsite for disposal at an
appropriately-permitted facility;
n Collect cleanup confirmation samples of remaining non-impacted soils from the
floors and sidewalls of excavated areas;
n Backfill and compact excavations, restore concrete and asphalt surfaces; and
n Prepare a report documenting the soil removal and disposal activities,
confirmation sampling results, and final condition of the site.
Keeping the buildings in place will complicate the excavation logistics of soil removal, and will limit
the extent to which soils can be removed without compromising the structures’ integrity. Impacted
soils will require waste characterization to identify an appropriate disposal facility and to generate
a waste profile for the facility. For the purpose of this evaluation, it is assumed the impacted soil
can be disposed of as non-hazardous waste. If any of the impacted soil is characterized as a
RCRA regulated hazardous waste, the wastes will be segregated, and the hazardous waste
portions will be sent to an approved hazardous waste landfill.
3.2.5 Alternative 5: TPH Fractionation and Development of SSCLs
This alternative seeks to use a risk-based approach to eliminate or reduce the need for
remediation of soil and groundwater at the site, due to the fact that the primary contaminant of
concern in these media is “TPH” (i.e., TPH-DRO, TPH-GRO, and/or TRPH). This risk-based
approach involves additional assessment of site-specific conditions and exposure pathways,
additional analyses including TPH fractionation, and evaluation of concentrations of the various
TPH fractions against calculated SSCLs rather than the DERR’s generic ISLs and Tier 1
Screening Levels. Depending on the results, the SSCLs may already be met for the potentially
complete exposure pathways, in which case remediation would not be necessary for protection
of human health. This alternative would generally include the following components:
Remedial Alternatives Evaluation
Lelis Transmissions ■ 845 South Main Street, Salt Lake City, Utah
ACRES ID#237101 ■ Terracon Project 61197491 ■July 20, 2020
Responsive ■Resourceful ■Reliable 13
n Collect additional soil and groundwater samples at locations where maximum
concentrations of TPH-DRO, TPH-GRO, and TRPH were identified in previous
investigations;
n Analyze the additional soil and groundwater samples for Utah TPH Fractionation
and for Semi-volatile Organic Compounds (SVOCs);
n Enter the resulting data and results from previous investigations, along with site-
specific physical parameters, in the DERR SSCL calculator; and
n Assess whether the calculated SSCLs are exceeded for any TPH fractions or
SVOC constituents. For SSCL exceedances, if any, evaluate whether the
corresponding exposure pathways are potentially complete or are not applicable
for the site.
With favorable TPH fractionation results and SSCLs, the remaining TPH in soil and groundwater
can be managed in place with controls such as restrictions on groundwater use, maintenance of
existing physical barriers over the impacted soils at depth, and establishment of soil management
procedures to be followed in the event of future excavation activity.
3.3 Recommended Cleanup Alternative
To achieve the Cleanup Objectives listed in Section 3.1, a multiple-component approach is
recommended as discussed below.
The “No Action” option (Alternative 1) is not considered a viable option since it does not meet the
redevelopment objectives and does not allow for a regulatory “No Further Action” status, nor does
it adequately protect from future exposure to site contaminants. At a minimum, attainment of “No
Further Action” status would likely require removal of onsite contaminant sources (Alternative 2)
and free product (a component of Alternative 3). Although full-scale application of Alternative 3
could likely remove most of the impacted groundwater, the benefit to groundwater quality may be
temporary as contaminated groundwater beneath upgradient properties will likely migrate
beneath the site over time. The impacted soil removal option (Alternative 4) could effectively
address the impacted soils (above generic screening levels) to a large extent, although this is the
most expensive and intrusive option evaluated. TPH fractionation and development of SSCLs
(Alternative 5) appears to offer a means of addressing the petroleum impacts in both soil and
groundwater without conducting extensive remediation of these media, assuming favorable
fractionation results and calculated SSCL values.
A multiple-component approach involving Alternatives 2, 3, and 5 is recommended. With this
approach, ongoing and/or future contaminant releases are prevented by removing the primary
contaminant sources (Alternative 2), and targeted free product removal (Alternative 3) eliminates
the remaining onsite source of groundwater contamination. Petroleum impacts to soil and
groundwater are addressed with TPH fractionation and development of SSCLs, and remaining
Remedial Alternatives Evaluation
Lelis Transmissions ■ 845 South Main Street, Salt Lake City, Utah
ACRES ID#237101 ■ Terracon Project 61197491 ■July 20, 2020
Responsive ■Resourceful ■Reliable 14
impacts are managed in place with appropriate controls such that no complete exposure
pathways exist.
Following implementation of a remedial strategy, a cleanup completion report would be generated
to document that the appropriate cleanup activities were completed and any residual
contaminants are controlled by meeting SSCLs or by incomplete exposure pathways. If needed,
a Site Management Plan (SMP) would also be developed to specify controls for the remaining
impacts, along with an Environmental Covenant to ensure that the controls are maintained during
future site use.
4.0 REFERENCES
Terracon Consultants, Inc. (Terracon)
2015 Limited Site Investigation Report, Lelis Transmissions, 845 South Main Street, Salt Lake
City, Utah, Terracon Project No. AL157378,August 18, 2015.
2018 Community Wide Quality Assurance Project Plan, Salt Lake County Brownfields
Assessment, EPA Cooperative Agreement No. 96835701, Salt Lake County, Utah,
Revision 2, May 24, 2018.
2019 Phase I Environmental Site Assessment, Lelis Transmissions, 845 South Main Street, Salt
Lake City, Salt Lake County,July 25, 2019.
2019 Sampling and Analyses Plan, Salt Lake County Brownfields Assessment, EPA
Cooperative Agreement No. 96835701, Hazardous Materials and Petroleum Grant for Salt
Lake County, Lelis Transmissions, 845 South Main Street, Salt Lake City, Salt Lake
County, Utah,August 19, 2019.
2019 Phase II Site Assessment,Sampling and Analyses Plan, Salt Lake County Brownfields
Assessment, EPA Cooperative Agreement No. 96835701: ACRES ID No. 237101,
Hazardous Materials and Petroleum Grant for Salt Lake County, Lelis Transmissions, 845
South Main Street, Salt Lake City, Salt Lake County, Utah,September 24, 2019; Revised
September 30, 2019.
U.S. Geological Survey Professional Paper 1270; Element Concentrations in Soils and Other
Surficial Materials of the Conterminous United States, 1984.
APPENDIX A
Exhibits
TOPOGRAPHIC MAP IMAGE COURTESY OF
THE U.S. GEOLOGICAL SURVEY
QUADRANGLES INCLUDE: SALT LAKE CITY
NORTH, UT (1/1/1998), FORT DOUGLAS, UT
(1/1/1998), SALT LAKE CITY SOUTH, UT
(1/1/1999) and SUGAR HOUSE, UT (1/1/1998).
TOPOGRAPHIC MAP
LELIS TRANSMISSIONS
845 South Main Street
Salt Lake City, UT6949 S High Tech Dr, Ste 100
Midvale, UT 84047-3707
61177082
DIAGRAM IS FOR GENERAL LOCATION ONLY,
AND IS NOT INTENDED FOR CONSTRUCTION
PURPOSES
Project Manager:
Drawn by:
Checked by:
Approved by:
AT
ABF
ABF
ABF
Exhibits
Sept 2019
Project No.
File Name:
Date:
1
Exhibit
1”=2,000’Scale:
SUBJECT
PROPERTY
SITE DIAGRAM
6949 S High Tech Dr, Ste 100
Midvale, UT 84047-3707
61177082AERIAL PHOTOGRAPHY PROVIDED BY
MICROSOFT BING MAPS
LELIS TRANSMISSIONS
845 South Main Street
Salt Lake City, UTDIAGRAM IS FOR GENERAL LOCATION ONLY,
AND IS NOT INTENDED FOR CONSTRUCTION
PURPOSES
Project Manager:
Drawn by:
Checked by:
Approved by:
AT
ABF
ABF
ABF
Exhibits
Sept 2019
Scale:
Project No.
File Name:
Date:
AS SHOWN 2
Exhibit
Legend
Drains
Hoists
Sump
Oil-Water Separator
APPROXIMATE
SITE BOUNDARY
Fo
r
m
e
r

U
S
T

B
a
s
i
n
AS
T
Undocumented UST
Removal (Adjoining
Property)
Sump
Oil-Water Separator
Parts Washing
LT-B-8
LT-B-9
LT-B-10
LT-B-11
LT-B-12LT-B-13
(Refusal)
Soil and Groundwater Sampling Points
6949 S High Tech Dr, Ste 100
Midvale, UT 84047-3707
61177082AERIAL PHOTOGRAPHY PROVIDED BY
MICROSOFT BING MAPS
LELIS TRANSMISSIONS
845 South Main Street
Salt Lake City, UTDIAGRAM IS FOR GENERAL LOCATION ONLY,
AND IS NOT INTENDED FOR CONSTRUCTION
PURPOSES
Project Manager:
Drawn by:
Checked by:
Approved by:
AT
ABF
ABF
ABF
Exhibits
Sept 2019
Scale:
Project No.
File Name:
Date:
AS SHOWN 3
Exhibit
Legend
Drains
Hoists
Sump
Oil-Water Separator
Soil Sampling Point
Soil & GW Sampling Point
APPROXIMATE
SITE BOUNDARY
Fo
r
m
e
r

U
S
T

B
a
s
i
n
AS
T
Undocumented UST
Removal (Adjoining
Property)
Sump
Oil-Water Separator
with French Drain
LT-B-1
LT-B-2
LT-B-3
LT-B-4
LT-B-5
LT-B-6
LT-B-7
LT-B-14 LT-B-15
LT-B-16
Soil Gas Sampling Points
6949 S High Tech Dr, Ste 100
Midvale, UT 84047-3707
61177082AERIAL PHOTOGRAPHY PROVIDED BY
MICROSOFT BING MAPS
LELIS TRANSMISSIONS
845 South Main Street
Salt Lake City, UTDIAGRAM IS FOR GENERAL LOCATION ONLY,
AND IS NOT INTENDED FOR CONSTRUCTION
PURPOSES
Project Manager:
Drawn by:
Checked by:
Approved by:
AT
ABF
ABF
ABF
Exhibits
Sept 2019
Scale:
Project No.
File Name:
Date:
AS SHOWN 4
Exhibit
Legend
Drains
Hoists
Sump
Oil-Water Separator
Soil Gas Sampling Point
APPROXIMATE
SITE BOUNDARY
Fo
r
m
e
r

U
S
T

B
a
s
i
n
AS
T
Undocumented UST
Removal (Adjoining
Property)
Sump
Oil-Water Separator
VP-1
VP-2
VP-3VP-4
APPENDIX B
Tables
Responsive ■Resourceful ■Reliable
Table 1 – Brownfield Cleanup Alternatives Balancing Factor Evaluation
Remedial
Alternative Effectiveness Long-term reliability Implementability Cost Implications
1. No Action Does not address
potential risks.
Does not address
potential risks.
Not applicable for No Action.No cost to implement.
Potential cost implications on property
value and future liabilities associated with
contaminant exposure.
2. Remove
Contaminant
Source Structures
Effectively removes
existing contaminant
sources including lift
hoists, used-oil AST,
sump, oil/water
separator, and floor
drains. Does not
address impacted soil
or groundwater.
Permanently eliminates
primary on-site
contaminant
contribution sources.
Relatively easily implemented. Would
require excavation equipment access
inside buildings and in the central open
area.
Moderate costs anticipated for removal,
backfilling, compaction, and surface
restoration.
3. Mobile Dual-
Phase Extraction
(MDPE)
Under favorable
conditions, effectively
removes petroleum as
free-phase product,
petroleum-impacted
groundwater, and as
vapors. Fluid recovery
can be limited by site
geology and
contaminant
characteristics.
Free product and
impacted groundwater
is removed from the
site. However,
impacted groundwater
may eventually return
to site by migration
from upgradient
contaminant sources.
Requires installation of extraction wells.
With large-scale MDPE application at
this site, permitting for treated water
discharge to Salt Lake City POTW may
prove challenging.
Smaller-scale vacuum-truck application,
targeting area affected by free product,
could be easily implemented without
discharge permitting issues.
Moderate to high costs anticipated for
large-scale MDPE application with
extraction throughout entire onsite area
containing impacted groundwater and
localized free product.
Low to moderate costs anticipated for
small-scale MDPE application with focus
only on area containing free product.
4. Remove
Impacted Soils
Effectively eliminates
onsite soil
contamination where
accessible to
excavation equipment.
Provides permanent
removal of soil
contaminants.
Access to the impacted soils will require
removal of approximately 7.5 to 10 feet
of non-impacted overburden soils, along
with surficial concrete and asphalt.
Retaining the buildings and limited
workspace will complicate the removal
operation and limit the amount of soil
that can be safely removed.
High costs anticipated due to site
conditions with limited workspace,
widespread occurrence of impacted soils
at depth, and need to remove of non-
impacted overburden to access the
impacted soils.
5. Conduct TPH
Fractionation,
Develop SSCLs
Favorable results
effectively demonstrate
protectiveness of
human health while
eliminating or reducing
Supports site re-
development with
contaminants remaining
in place. Long-term
site management
Easily implemented. Will require
collection of additional soil and
groundwater samples with analysis for
Utah TPH Fractionation and SVOCs.
Use analytical results and site-specific
Moderate costs anticipated for additional
sampling, laboratory analyses, SSCL
development, and exposure pathways
evaluation.
Responsive ■Resourceful ■Reliable
for Soil and
Groundwater
need for remediation of
petroleum-impacted soil
and groundwater.
Does not address lead
impacted soils, though
these can be managed
in place along with
petroleum-impacted
soils.
controls may be
needed to prevent
exposure to impacted
soils at depth, and to
prevent use of
impacted groundwater.
physical parameters to develop SSCLs
and compare against concentrations of
specific TPH fractions and SVOC
constituents. If any SSCL exceedances
are identified for complete exposure
pathways, develop appropriate controls
(e.g., maintenance of physical barriers
or groundwater use restrictions) to close
the exposure pathway.
Responsive ■Resourceful ■Reliable
Table 2 – Estimated Comparative Costs for Cleanup Alternatives
Cleanup Alternative Estimated Costs Notes
1. No Action $0 Not a viable option.
2. Remove Contaminant
Source Structures $49,340 - $53,575 Removal and disposal of structures and contents. Contractor rough estimates based on similar
projects. Assumes non-hazardous waste disposal. Includes all labor and equipment
necessary.Includes import backfill and compaction.
$18,400 Remove and dispose 8 lift hoists.
$3,450 Remove and dispose 6 floor drains.
$4,600 - $5,750 Remove and dispose sump.
$4,600 - $5,750 Remove and dispose oil/water separator
$2,875 Remove and dispose used-oil AST
$15,415 - $17,350 Cleanup planning document preparation, public notification of proposed cleanup,
Terracon oversight during remediation, completion report.
3. Mobile Dual-Phase
Extraction (MDPE)Large-scale / sitewide
$103,905
Small-scale / targeted
$24,325
Contractor rough estimates based on similar projects. Assumes non-hazardous waste
disposal.Includes all labor and equipment necessary.
Large-scale MDPE application, targeting impacted groundwater sitewide and free product area:
$14,030 Install 12 temporary extraction wells, abandon after MDPE treatment
$57,500 Conduct 30-day MDPE treatment event with full MDPE system. Assumes
disposal of treated water to Salt Lake City sewer system, and disposal of free
product as non-hazardous waste.
$550 Laboratory/Analytical (discharge compliance samples)
$31,825 Cleanup planning document preparation, permitting, public notification of
proposed cleanup, Terracon oversight during remediation, completion report.
Small-scale MDPE application; targeting free product area only:
$5,235 Install 4 temporary extraction wells, abandon after MDPE treatment.
$7,740 Conduct MDPE treatment events with vacuum truck (assume 2 one-day treatment
events). Assumes disposal of up to 500 gallons of recovered fluids as non-
hazardous waste per treatment event.
$11,350 Cleanup planning document preparation, permitting, public notification of
proposed cleanup, Terracon oversight during remediation, completion report.
Responsive ■Resourceful ■Reliable
Cleanup Alternative Estimated Costs Notes
4. Remove Impacted
Soils $177,740 - $199,575
Removal and disposal of impacted soil. Contractor rough estimates based on similar projects.
Assumes non-hazardous disposal at industrial petroleum waste facility. Includes all labor and
equipment necessary.Includes import backfill and compaction.
$143,750 - $161,000 Remove, transport, and dispose of impacted soils at typical depth range of 8 to
10 feet. Assumes a 10,000 ft2 area with disposal of 1250 to 1400 tons.
$4,515 - $5,580 Laboratory/Analytical (soil cleanup confirmation samples). Assumes 20 to 25 soil
samples with next-day laboratory analysis for TRPH and TPH-DRO, with 5
additional analyses for TPH-GRO.
$29,475 - $32,995 Cleanup planning document preparation, public notification of proposed cleanup,
Terracon oversight and sampling during remediation, completion report.
5. Conduct TPH
Fractionation, Develop
SSCLs $15,230*Collect additional soil and groundwater samples, analyze for Utah TPH Fractionation and
Semivolatile Organic Compounds. Evaluate results against SSCLS using Utah DEQ/DERR
SSCL calculator, assess exposure pathway status.
$2,590 Drilling services for soil and groundwater sampling
$5,015 Laboratory analyses
$7,625 Terracon field sampling, data analysis, report preparation
Estimated Cost Range for Cleanup Alternatives - $266,635 to $372,285
*Costs may be covered by Salt Lake Coalition Assessment Grant.
Estimated costs do not include regulatory oversight by either the VCP or the LUST Program.