South Hollis LOSO Decision Memorandum 20220322

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South-Hollis/24062-20-060/20220322
DECISION MEMORANDUM
DATE: March 22, 2022 FROM: Bill Schmithorst TO: BF Assessment File
RE: South and Hollis LoSo 3423, 3435, and 3441 South Boulevard and 111 Hollis Road Charlotte, Mecklenburg County Brownfields Project Number 24062-20-060
Based on the following information, it has been determined that the above referenced site, whose intended use is for no uses other than high density residential, office, restaurant, retail, recreational, parking, and with prior DEQ approval, other commercial
uses can be made suitable for such uses. Introduction: The Brownfields Property is located at 3423, 3435, and 3441 South Boulevard and 111 Hollis Road in Charlotte, Mecklenburg County, North Carolina. The Brownfields
Property consists of seven contiguous parcels (Mecklenburg County Parcel Identification Nos. 14905301, 14905302, 14905303, 14905305, 14905306, 14905314, and 14905315) totaling approximately 2.6 acres of land located in a mixed commercial and residential area of South End Charlotte.
The northwestern Brownfields Property parcel (3423 South Boulevard; PIN 14905314) is developed with an approximate 3,984 square foot (sq ft) commercial building that was occupied by an auto painting facility. The western parcel (3435 South Boulevard; PIN 14905315) is developed with an approximate 3,492-sq ft warehouse building occupied by
a lawn equipment rental and repair company. The southwestern parcel (3441 South
Boulevard; PIN 14905301) is developed with an approximate 7,450-sq ft commercial building that was most recently occupied by a sweepstakes store. Remaining portions of the Brownfields Property consist of vacant land and asphalt and gravel parking lots and driveways. The eastern portion of the site was recently put into use as a contractor storage
yard for utility work on South Boulevard.
Redevelopment Plans: KA LoSo Holdings LLC plans to redevelop the property for mixed-use including high-density residential, retail, restaurant, office, parking, recreational, and other commercial
uses. The existing buildings will be razed. The PD intends to install a vapor mitigation
system in the new buildings. Site History:
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The Brownfields Property consisted of agricultural land and a rural residence in the early 1900s. By the 1940s, a commercial building/gas station was developed in the
southwestern corner of the Brownfields Property. By the mid-1950s, the northwestern and western site buildings were constructed along South Boulevard and an additional residence was constructed in the central portion of the Brownfields Property. The northwestern site building (3423 South Boulevard) was utilized as a machining and metal working company from at least the 1950s until the early 1960s, was occupied by an auto
painting facility until 2021 when it was vacated for future development. The western site building (3435 South Boulevard) has been utilized as a lawn equipment repair facility since the early 1960s. The southwestern portion of the Brownfields Property (3441 South Boulevard) was utilized as a gas station from the 1950s until the early 1960s and as a night club or sweepstakes store from the late 1960s until recently.
Environmental Assessment Activities A Phase I Environmental Site Assessment was conducted in September 2020 (Hart & Hickman, September 2020). The following conditions were documented during the site reconnaissance activities:
• a vent pipe associated with a suspect heating oil underground storage tank (UST) located adjacent to the exterior wall of the 3423 South Boulevard building.
• Oil staining was observed near multiple 55-gallon drums of waste oil located
outside and adjacent to the 3435 South Boulevard site building.
A Phase II Environmental Site Assessment was conducted, in accordance with a DEQ-approved work plan, at the site in April 2021. Details from the site assessment including sampling locations and laboratory results are presented in Site Assessment Report, South
and Hollis LOSO, June 9, 2021, Hart & Hickman. Assessment activities included
collecting soil, groundwater and soil gas samples. A ground penetrating radar (GPR) survey was conducted in the area of the former gasoline station UST bed. Results of the GPR study did not identify anomalies consistent with USTs. Soil samples were located in recognized areas of concern identified during the Phase I Site Assessment. Twelve soil
borings were advanced at the previously identified areas of concern to collect soil
samples for laboratory analysis, including volatile organic compounds (VOCs), semi-volatile compounds (SVOCs), and RCRA metals plus hexavalent chromium. In addition, three composite soil samples were collected from a soil stockpile located at the southeastern corner of the property.

Soil sample laboratory results indicated that no VOCs were detected above Residential Preliminary Soil Remediation Goals (PSRGs). Laboratory results indicated that one SVOC, pentachlorophenol was detected in soil (SB-2) at a concentration above Residential PSRGs. Arsenic was detected in two soil samples at concentrations above
Residential PSRGs.
Six temporary groundwater monitoring wells were installed and sampled for the laboratory analysis of VOCs, SVOCs, and RCRA metals. Laboratory results indicated that chloroform was the only contaminant detected in groundwater at a concentration
above North Carolina 2L Groundwater Quality Standards.
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In addition, 10 temporary exterior soil gas monitoring points were installed at the
Brownfields Property within the footprint of the proposed development and sampled for laboratory analysis of VOCs. Laboratory results indicated that 1,1,2,2-tetrachloroethane, naphthalene and benzene were detected above DWM Residential Soil Gas Screening Levels.
Potential Receptors: Potential receptors are: construction workers, on-site workers, future residents, visitors, animals (dog park/farm animals), and trespassers. A receptor survey was completed in April 2021. No water supply wells were identified within 1,500 feet of the Brownfields Property. In addition, no surface water is located onsite.
Contaminated Media: DEQ has evaluated data collected from the following media at the subject property: soil, groundwater, and soil gas. DEQ relies on the following data to base its conclusions regarding the subject property and its suitability for its intended reuse. Environmental
sample contaminant concentrations exceeding screening levels are presented in Exhibit 2 of Appendix A of the Notice of Brownfields Property. Soil
• Laboratory results indicated that no VOCs were detected in soil above Residential PSRGs.
• Pentachlorophenol was the only SVOC detected in soil sample, SB-2 (4-6 ft bgs), above Residential PSRGs at a concentration of 6.3 mg/kg.
• Arsenic was also detected in two soil samples (SB-6 and SB-7) above Residential PSRGs at a concentration of 2.0 mg/kg.
Groundwater
• Laboratory analytical results indicated the presence of tetrachloroethylene (PCE) in TMW-6 (2.1 μg/L) above the 2L Standard of 0.7 μg/L. Trichloroethylene was also detected at TMW-6 at a concentration of 0.44J, this is below the 2L Standard.
• Laboratory analytical results indicated that chloroform was detected above
Residential Vapor Intrusion Groundwater Screening Levels in monitoring wells TMW-4 and TMW-5 at concentrations of 1.1 J ug/L and 2.2 ug/L. Surface Water
Surface water is not located on the Brownfields Property.

Soil Gas
• 1,1,2,2-tetrachloroethane was detected in sample SG-7 (30.3 μg/m3) at a
concentration above the Residential SGSL.
• Sample SG-7 contained a concentration of benzene (13.0 J μg/m3) slightly above the DWM Residential SGSL.
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• Naphthalene was detected in sample SG-2/SG-DUP (6.1 μg/m3 / 3.74 μg/m3)
above the DWM Residential SGSL.
• Trichloroethylene was detected in sample SG-9 (1.41 J ug/m3) at a concentration below the Residential SGSL.
Sub-Slab Vapor
Sub-slab vapor samples not collected. The existing buildings will be demolished for the new development. Indoor Air No indoor air samples collected. The existing buildings will be razed.

Risk Calculations Risk calculations were performed using the DEQ Risk Calculator (June 2021 version). Laboratory data from the soil, groundwater, and soil gas samples with the highest
concentrations of site wide contaminants were used in the risk calculator for those
environmental media.
Risk for Individual Pathways Output Form 1A
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: 24062-20-060
Exposure Unit ID: Site wide highest conc all media
Receptor Pathway Carcinogenic Risk Hazard Index Risk exceeded?
Soil 8.4E-06 9.8E-02 NO
Groundwater Use*1.1E-05 6.0E-01 NO
Soil 2.1E-06 9.0E-03 NO
Groundwater Use*2.5E-06 1.5E-01 NO
Construction Worker Soil 2.7E-07 9.7E-02 NO
Soil 4.7E-06 5.0E-02 NO
Surface Water*NC NC NC
Receptor Pathway Carcinogenic
Risk Hazard Index Risk exceeded?
Groundwater to Indoor Air 3.3E-06 2.0E-01 NO
Soil Gas to Indoor Air 2.6E-05 8.3E-01 NO
Indoor Air NC NC NC
Groundwater to Indoor Air 7.3E-07 4.9E-02 NO
Soil Gas to Indoor Air 2.0E-06 6.6E-02 NO
Indoor Air NC NC NC
DIRECT CONTACT SOIL AND WATER CALCULATORS
Resident
Non-Residential Worker
Recreator/Trespasser
VAPOR INTRUSION CALCULATORS
Resident
Non-Residential Worker

The risk calculations indicated the following based on available data, including the following media: groundwater, soil, and soil gas. Results from the risk evaluation indicate that risk indices were not exceeded. Based on the presence of low concentrations of TCE is soil gas, the PD is planning to install a passive vapor mitigation system. Pre-occupancy indoor air sampling will be required. Additional mitigation system monitoring
requirements will be included in the Vapor Intrusion Mitigation Plan. An Environmental
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Management Plan (EMP), approved by DEQ, will be required before the start of soil grading or excavation activities to prevent exposure to site workers and future residents
from unacceptable levels of contaminants, and to manage the safe handling and disposal of potentially contaminated materials during construction. In addition, final grade soil sampling will be required prior to occupying the Brownfields Property. Required Land Use Restrictions:
The standard land use restrictions including land use, Environmental Management Plan and reporting requirements, prohibition on groundwater use, soil restrictions, the need for vapor intrusion mitigation in certain areas, access, notification, and prohibition on the use of known contaminants, and the annual land use update obligation are required for this
Brownfields Agreement. Based on the site-specific data provided to the Brownfield program, the site reuse is suitable for the site as long as the agreed upon land use restrictions in the BFA are abided by.
Property Management
• New construction will include vapor mitigation as well as associated pre-occupancy monitoring.
• Environmental Management Plan
• Final grade soil sampling