23056 Affordable Custom Iron Decision Memorandum 20201005

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DECISION MEMORANDUM
DATE: October 5, 2020 FROM: Bill Schmithorst TO: BF Assessment File
RE: Affordable Custom Iron 3804 South Boulevard Charlotte, Mecklenburg County BF #23056-19-060
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, retail, office, recreational, parking, open space, and with prior written DEQ approval, other commercial uses, can be made suitable for such uses.
Introduction: The Brownfields Property consists of an approximate 3.872-acre parcel of land (Parcel Identification Number 14901239) that is currently vacant and undeveloped.
Redevelopment Plans: The Prospective Developer plans to construct a mixed-use development containing high density residential, retail, office, recreational, parking, open space and commercial space that will also have commuter parking servicing the light rail line.
Site History: According to the Phase I Environmental Assessment Report (May 22, 2019), the Brownfields Property was initially developed with a residence. Around 1938, the Brownfields Property appears to have been developed with residential structures and a
commercial/warehouse building. The Brownfields Property was developed with
warehouse/commercial building and a drive-in theater around 1967, and the drive-in theater was demolished during the 1980s. An additional commercial building and associated parking lot was developed in approximately 1983 and demolished in about 2006. The Brownfields Property was purchased by the City of Charlotte on April 25,
2006 for transit oriented development primarily in support of the South Corridor Light
Rail, and a parking lot was subsequently developed in 2009. The remaining warehouse/commercial buildings were demolished between approximately 2006 and 2012. Tenants at the subject property have included Affordable Custom Iron, Consolidated Steel Services, Queen Drive-In Theatre, Piedmont Theaters Office, Queen
City Cinema, Assistance League of Charlotte, Piedmont Theatres, and Queen Park
Cinema. Property located to the north of the Brownfields Property was formerly occupied by Consolidated Steel Services, a structural steel fabricator and constructor. Portions of the
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Consolidated Steel Services, consisting of parking and storage, were located on the northern part of the Brownfields Property.
A surface spill, consisting of motor oil spillage from parked vehicles, pails of waste oil, and suspected spillage and over-spray from an ornamental iron spray booth. was discovered on January 16, 2006 at the former location of Affordable Custom Iron. The spill was reported to the NCDEQ (Incident #91008).

Environmental Assessment A Phase II environmental assessment was conducted at the Brownfields Property in June and July 2007 for property due diligence purposes. Assessment activities included
collecting soil samples for the laboratory analysis of volatile organic compounds, semi-volatile organic compounds and RCRA metals. The site assessment included the areas of the Brownfields Property previously used by Consolidated Steel Services for parking and storage and the former Affordable Custom Iron location. Laboratory results from the former Affordable Custom Iron facility indicated that soil contaminants exceeded
NCDEQ Inactive Hazardous Sites Branch (IHSB) Health-Based Remediation Goals (RG) or the NCDEQ Soil-to-Groundwater Maximum Soil Contaminant Concentrations (MSCCs) at two locations. A DEQ incident number was opened, DEQ UST Incident No. 91008, upon reporting the discovery. The contaminants included benzene, carbon tetrachloride, and arsenic at location TP-1 and benzo(a)pyrene and
dibenzo(a,h)anthracene at location SS-3. Based on results from the site assessment, approximately 76 tons of impacted soil were excavated from the areas of contaminated soil in June and July 2007 and disposed of at a regulated facility. Laboratory results from post excavation sampling indicated that there were no detections above screening levels. A No Further Action Letter was issued for Incident No. 91008; however, the discovery of
non-petroleum contamination (carbon tetrachloride and arsenic) was referred to the DEQ Inactive Hazardous Site Branch (IHSB). IHSB has not required additional assessment of the reported incident; however, a No Further Action Letter has not been issued.
Laboratory results from the former Consolidated Steel Services property indicated soil
contamination from total petroleum hydrocarbons originating from spills/leaks from parked vehicles and small storage containers (DEQ UST Incident No. 91007). Approximately 325 tons of impacted soils were removed from the Brownfields Property in June and July 2007 and were disposed of at an off-site treatment facility. Post-
excavation samples collected at the bottom of the excavations indicated no exceedances
of NCDEQ IHSB Health-Based RG or the MSCCs. On September 24, 2007, the NCDEQ UST Section issued a No Further Action (NFA) letter for Incident No. 91007. An environmental site assessment consisting of passive soil gas monitoring was
conducted at the Brownfields Property in August and September 2019 for property due
diligence purposes. Soil gas samples were collected for the analysis of VOCs using passive soil gas samplers at 37 locations across the Brownfields Property in September 2019. Laboratory results indicated that one exceedance above DEQ Residential vapor
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intrusion screening levels (VISLs) was detected for naphthalene near the location of the former Affordable Custom Iron facility.
A brownfields environmental site assessment was conducted in March 2020 in accordance with a DEQ-approved work plan dated January 20, 2020. Assessment activities included collecting 10 soil samples for the analysis of VOCs, semi-volatile organic compounds (SVOCs) and Resource Conservation and Recovery Act (RCRA)
metals, four soil gas samples for the analysis of VOCs by USEPA Method TO-15, and groundwater samples collected from two temporary groundwater monitoring wells for the analysis of VOCs, SVOCs, and RCRA metals. Soil laboratory results indicated that Residential Preliminary Soil Remediation Goals (PSRGs) were exceeded for arsenic, cadmium, and hexavalent chromium. In addition, groundwater laboratory results
indicated that chromium exceeded the North Carolina 2L Groundwater Standards. No soil gas contaminants were detected above NCDEQ Residential VISLs. Potential Receptors: Potential receptors are: construction workers, on-site workers, future residences.
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.

Soil Laboratory results from the March 2020 environmental investigation indicated exceedances of Residential PSRGs for metals in soil, including arsenic, cadmium, and hexavalent chromium. Arsenic exceeded Residential PSRGs in all 10 soil samples, with
the highest being 52.7 mg/kg from soil sample SB-9 collected at a depth of 4 ft. below ground surface. Cadmium exceeded Residential PSRGs in sample SB-9 at a concentration of 54.6 mg/kg. Hexavalent chromium exceeded Residential PSRGs in soil samples SB-3, SB-7, SB-8; however, the hexavalent chromium concentrations were
below 1.0 mg/kg and within expected background levels. No VOCs or SVOCs were
detected in soil samples above Residential PSRGs. A soil sample was collected from the area where naphthalene was detected during the September 2019 passive soil gas assessment and laboratory results indicated that naphthalene was not detected.
Groundwater
Two shallow groundwater samples were analyzed for VOCs, SVOCs, and RCRA metals. Chromium was detected above 15A NCAC 02L Groundwater Standards (2L Groundwater Standards) in temporary monitoring wells MW-1 and MW-2 at concentrations of 21.0 µg/L 11.0 µg/L, respectively. Low levels of acetone and
bromodichloromethane were detected in groundwater; however, no constituents were
detected above North Carolina Groundwater Vapor Intrusion Screening Levels (VISLs) or 2L Groundwater Standards. An additional groundwater monitoring well was installed at the site; however, shallow bedrock presented difficulties during drilling and the resulting well was dry when sampling was attempted.
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Surface Water Surface water is not located at the site.
Soil Vapor Laboratory VOC results from a September 2019 passive soil gas assessment indicated a
detection of naphthalene above Residential VISLs. In March 2020, four temporary soil gas sampling points were installed and sampled for the analysis of VOCs by USEPA Method TO-15 at the Brownfields Property to assess soil gas conditions, including one sample (SG-3) from the same area where naphthalene had been detected during the September 2019 passive soil gas assessment. Laboratory results from the March 2020
assessment indicated that low levels of petroleum-related compounds were detected; however, soil gas sample laboratory results indicated that no VOCs were detected above Residential VISLs. In addition, these laboratory results indicated that naphthalene was not detected in soil gas samples.
Risk Calculations Risk Calculations were performed using the NCDEQ Risk Calculator Tool (December 2019 version). For the purposes of looking at the worst case scenario, the samples with the highest concentrations of contaminants were used for calculating risk, including SB-9 for soil, MW-2 DUP-1 for groundwater, and SG-3 for soil gas. The risk calculations
indicated the following based on available soil data.
DIRECT CONTACT SOIL AND WATER CALCULATORS
Receptor Pathway Carcinogenic Risk Hazard Index Risk exceeded?
Resident Soil 5.0E-04 3.0E+00 YES
Groundwater Use* 1.0E-03 8.7E-01 YES
Non-Residential Worker
Soil 3.7E-05 2.1E-01 NO
Groundwater Use* 1.0E-04 2.0E-01 YES
Construction
Worker Soil 3.9E-05 3.0E+00 YES
Recreator/Trespasser Soil 2.8E-04 1.6E+00 YES
VAPOR INTRUSION CALCULATORS
Receptor Pathway Carcinogenic Risk Hazard Index Risk exceeded?
Resident
Groundwater to
Indoor Air 4.2E-07 0.0E+00 NO
Soil Gas to Indoor
Air 1.5E-06 1.8E-02 NO
Non-Residential
Worker
Groundwater to
Indoor Air 9.7E-08 0.0E+00 NO
Soil Gas to Indoor Air 1.1E-07 1.5E-03 NO
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Red shading LICR> 1E-04 or HI> 1.
LICR = Lifetime Incremental Cancer Risk HI = Hazard Index Risk Calculator results indicate that the Hazard Index for soil at the Brownfields Property is above a Hazard Index (HI) of 1.0 under Residential and Construction Worker
scenarios, primarily due to elevated concentrations of arsenic. In addition, groundwater exceeded an HI of 1.0 under Residential and Non-Residential Use scenarios due to the elevated chromium concentrations. Brownfields Land Use Restrictions will require that areas of contaminated soil with unacceptable risks be addressed through remedial measures that allow safe reuse of the property, and also prohibit the use of groundwater.
An unacceptable risk was not identified in soil gas at the Brownfields Property; therefore, vapor mitigation will not be required for the proposed development. An Environmental Management Plan (EMP) has been prepared by the Prospective Developer and approved by DEQ, and the EMP is being used to prevent exposure to site
workers and potential future residents from unacceptable levels of contaminants, and to manage handling and disposal of potentially contaminated materials during construction. Required Land Use Restrictions:
Based on the site-specific data provided to the Brownfield program, the site reuse is suitable for the site as long as the PD/land owner complies with the agreed upon land use restrictions. A summary of the land use restrictions (LURs) is provided below. 1. No use other than high density residential, retail, office, recreational, parking, open
space, and with prior written DEQ approval, other commercial uses. 2. No groundwater use 3. No disturbing soil without DEQ approval or for landscape/mowing/pruning/repair of underground infrastructure (written notice to DEQ)/work for EMP.
4. Soil Import/Export must be approved by DEQ.
5. DEQ approved EMP 6. Access to Brownfields Property for environmental assessment. 7. Standard vapor intrusion LUR 8. No child care or adult care centers.
9. NBP reference in deed.
10. No contaminants (as included in Ex. 2 to the BFA) on property except for de minimis amounts, fluid in vehicles, fuels for generators/equipment. 11. Final grade soil sampling for RCRA metals, SVOCs, and VOCs will be conducted in exposed areas.
12. LURU submission January 1st