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HomeMy WebLinkAbout23070 Red Carpet Inn Decision Memorandum 202111021 DECISION MEMORANDUM DATE: November 2, 2021 FROM: Bill Schmithorst TO: BF Assessment File RE: Red Carpet Inn 615 East Morehead Street Charlotte, Mecklenburg County BF Project No. 23070-19-060 Based on the following information, it has been determined that the above referenced Brownfields Property, whose intended use is for no uses other than retail, high density residential, office, brewery or food production facility, distillery, restaurant, entertainment, institutional, hotel, open space, recreational, and associated parking, and with prior written DEQ approval, other commercial uses, can be made suitable for such uses. Introduction: The Prospective Developer is MOD CLT Property, LLC a limited liability company headquartered at 205 East 42nd Street, 20th Floor, New York, New York 10017. The Brownfields Property consists of two adjoining parcels totaling 2.84 acres located at 615 East Morehead Street in Charlotte, North Carolina (Parcel Nos. 125-175-06 and 125-175-19). The northeastern portion of the Brownfields Property is developed as an asphalt-paved parking area. The southwestern portion of the Brownfields Property is presently undeveloped grass and gravel covered land that was formerly developed as a four-story hotel (Red Carpet Inn) that was most recently used as an elderly housing facility, and a two-story parking garage. Redevelopment Plans: The southwestern portion of the Brownfields Property will be developed as a retail/office/commercial building and parking deck while the northeastern portion of the property will be developed as high density residential. Site History: The Brownfields Property was developed with multiple residences from at least 1938 until the early 1960s. By the mid-1960s, residential buildings were razed in the southwestern portion of the Brownfields Property and replaced by a commercial building (hotel). Residences in the northeastern portion of the Brownfields Property remained until the early 1980s. The northeastern parcel was undeveloped until the currently existing paved parking lot was constructed in the late 1990s. In the early 2000s, the commercial building in the southwestern portion of the Brownfields Property was razed. 2 Surrounding properties were mostly developed as residential from at least 1938 until the late 1940s, when commercial development increased along E. Morehead Street. Commercial development continued to increase along E. Morehead Street, to the northwest, southwest and southeast throughout the 1950s and 1960s. By the early 1990s, Interstate 277 and several interchanges were developed to the north and northeast of the Brownfields Property. Commercial development continued to increase along E. Morehead Street to the northwest, southwest and southeast through the 2000s, similar to current conditions. Site Vicinity The northwestern adjacent property (512 E. Morehead Street) is identified on the Underground Storage Tank (UST), Leaking UST (LUST), Institutional Control (IC), and Aboveground Storage Tank (AST) databases. Reportedly, the facility formerly operated a 5,000-gallon gasoline UST as part of onsite operations for Rea Construction Company. Upon removal of the tank in 1995 and the discovery of soil and groundwater impacts, the North Carolina Department of Environmental Quality (NCDEQ) identified the release as UST Incident No. 15378. Based on a review of the available regulatory information, approximately 6,850 tons of petroleum-impacted soil were removed from the source area of the former offsite UST. Multiple groundwater sampling events and other remedial activities were conducted at the adjacent property from 1995 through 2015. Groundwater analytical results from November 2016 identified various petroleum constituents above NC 2L Groundwater Quality Standards but below Gross Contamination Levels. Based on these results, the NCDEQ closed this release incident with a Notice of Residual Petroleum (NORP) in 2017. Groundwater is reported to be found at a depth of approximately 17 feet below ground surface (bls) and flow from west to east across the Brownfields Property. Environmental Assessment According to the Phase I Environmental Assessment Report (December 10, 2020), the only Recognized Environmental Condition identified at the Brownfields Property was the documented residual groundwater contamination associated with a petroleum release discussed above (NCDEQ UST Incident No. 15378) on the northern adjacent and up-gradient property. Subsurface environmental investigations have been conducted at the Brownfields Property since 1996 to investigate impacts related to this release (NCDEQ Incident No. 15378). A summary of historical environmental sampling analytical results is provided in Brownfields Soil Vapor Evaluation, Terracon Consultants, Inc., May 26, 2021. In 1996, as part of Comprehensive Site Assessment activities in response to the release on the adjacent property, four soil samples were collected (B-6, B-7, B-8, and B-11) and three permanent monitoring wells (MW-6, MW-7, and MW-10) were installed on the Brownfields Property. Total petroleum hydrocarbon (TPH) concentrations were not 3 identified in the soil samples. Petroleum constituents were identified in MW-6 above both NC 2L Groundwater Quality Standards (NC 2L Standards) and the current North Carolina Residential Vapor Intrusion Groundwater Screening Levels (VI-GWSLs). Petroleum constituents were not identified above NC 2L Groundwater Quality Standards in MW-7; however the semi-volatile organic compound (SVOC) bis(2-ethylhexyl)phthalate was detected in MW-7 above the NC 2L Groundwater Quality Standard. In 2000, LAW collected additional groundwater samples from MW-6, MW-7, and MW-10. Petroleum concentrations within MW-6 had decreased significantly relative to the past sampling event in 1996; however, multiple compounds, including benzene, ethylbenzene, and xylenes remained above both NC 2L Standards and current residential VI-GWSLs. In 2000, 12 soil borings (P-1 through P-12) were advanced in the northwestern portion of the Brownfields Property to evaluate the extent to which contaminated groundwater migrating from the adjacent property had impacted soils on the property. Low level petroleum impacts were identified in soils ranging from 4 to 16 feet bls, with most constituent concentrations below their Residential Preliminary Soil Remediation Goals (PSRGs). Naphthalene was identified between 12 and 16 feet bls in P-2 at concentrations exceeding the Residential PSRG. In addition, two temporary monitoring wells (TW-1 and TW-2) and one permanent monitoring well (MW-11) were installed at the Brownfields Property. Volatile petroleum hydrocarbons (VPH) were identified in both TW-1 and TW-2 above NC 2L Groundwater Quality Standards. Higher volatile organic compounds (VOCs) concentrations were detected in TW-2, and benzene, toluene, ethylbenzene, and xylene were identified above both the NC 2L Standards and residential VI-GWSLs in TW-2. In 2004, in conjunction with on-going assessment at the adjacent property, a groundwater sample was collected from onsite monitoring well MW-6. Groundwater concentrations remained elevated, with benzene, ethylbenzene, and xylene remaining above both 2L Standards and residential VI-GWSLs. In 2005, a geotechnical investigation was conducted in advance of planned site redevelopment. Eleven borings were advanced at the Brownfields Property, four of which (B-5, B-8, B-9, and B-10) were selected for environmental evaluation. Soil samples were collected from each of these borings. Temporary monitoring wells (MW-1 through MW- 4) were also installed in the borings. MW-1 was not sampled because of insufficient water volume. Groundwater samples were collected from MW-2, MW-3, and MW-4 as well as existing permanent monitoring well MW-10. Low level petroleum impacts were identified in soils ranging from 13.5 to 20 feet bls; however, none of the detected concentrations exceeded Residential PSRGs. Benzene, toluene, ethylbenzene, and xylene were identified above NC 2L Standards and residential VI-GWSLs in MW-2. Benzene was also identified in MW-3 above the NC 2L Standards. Methyl tert butyl ether (MTBE) was identified in MW-10 above its NC 2L Standard. Petroleum constituents were not identified above their respective NC 2L Standards in MW-4. 4 In 2014, two rounds (January and July) of groundwater sampling were completed at the adjacent property and the Brownfields Property. As part of the first round of sampling, two temporary wells (HTTW-4 and HHTW-5) were installed at the Brownfields Property and sampled along with MW-6. VPH and benzene were identified above NC 2L Standards in HTTW-4. Ethylene dibromide (EDB) was detected above the NC 2L Standard, and trichloroethylene was detected above residential VI-GWSLs in HTTW-5. During both sampling events, petroleum concentrations in MW-6 were relatively similar to those identified during the most recent previous sampling events. On February 22, 2017, NCDEQ issued a letter indicating that available data allowed the 521 Morehead Street site to be reclassified as low risk and granted No Further Action status for UST Incident 15378. An environmental assessment was conducted at the Brownfields Property in February 2020 for property due diligence purposes. Assessment activities included collecting three groundwater samples, four subsurface soil samples, two background soil samples, and five soil gas samples. Soil samples and groundwater samples were submitted to a laboratory for the analysis of VOCs, SVOCs, and Resource Conservation and Recovery Act (RCRA) metals. Soil borings TW-1 and TW-2 were located near the northwestern property boundary (southwestern parcel) to evaluate petroleum impacts from the documented petroleum release on the up-gradient adjacent property. Boring TW-3 was located in the south-central portion of the Brownfields Property, down-gradient of borings TW-1 and TW-2 to evaluate the potential for lateral petroleum impacts from the adjoining property to the northwest. Boring TW-4 was located in the central portion of the northeastern parcel where high density residential is planned for development, and hydraulically downgradient of former monitoring well MW-6. The four soil borings (TW-1, TW-2, TW-3 and TW-4) were converted to temporary monitoring wells to evaluate the extent of petroleum impacts in the groundwater from the adjoining up-gradient property. Boring TW-1 was advanced to a depth of 35 feet bls, but the well remained dry for over 48 hours and a water sample was not obtained from the well. Borings TW-2, TW-3 and TW-4 were advanced to depths of 24, 31, and 40 feet, respectively, where groundwater was encountered. Three of the exterior soil gas sampling points (SV-03, 2021-SV-03, and SV-05) were located on the parcel where residential development is planned and downgradient from the adjacent UST incident. Two additional soil gas points (TW-1 and 2021-SV-02) were located adjacent to groundwater monitoring wells TW-1 and TW-2, and also downgradient of the northwestern adjacent property. Laboratory results from the February 2020 environmental assessment indicated that low concentrations of petroleum-related VOC compounds were detected from a soil sample collected at a depth of 10-15 ft. bls; however, none of the compounds detected exceeded 5 their respective NCDEQ Residential PSRGs. In addition, laboratory results indicated several petroleum-related VOCs and SVOCs exceeded their respective NCAC 2L Groundwater Quality Standards in samples collected from monitoring wells TW-2 and TW-3. Laboratory results from the exterior soil gas sampling indicated that chloroform was the only VOC compound detected at concentrations exceeding an established NCDEQ Residential Soil Gas Screening Level (SGSL), although there were detections of other compounds in the soil gas without established SGSLs (see Exhibit 2 for these data). An additional soil gas assessment was conducted in March 2021 in accordance with a DEQ-approved work plan. The purpose for the assessment was to address data gaps within the footprint of the proposed redevelopment and to confirm previous soil gas assessment results. Five soil gas sampling points (2021-SV-01, 2021-SV-02, 2021-SV- 03, 2021-SV-04, 2021-SV-05) were installed and sampled for the analysis of VOCs. Laboratory results indicated that no VOCs were detected above their respective Residential SGSLs. Potential Receptors: Potential receptors are: construction workers, onsite workers, future residents, visitors, and trespassers. No groundwater supply wells were located within 1,500 feet of the Brownfields Property. There were no contaminant sources identified from historical onsite activities. Contaminated Media: DEQ has evaluated data collected from the following media at the subject property: groundwater, soil and exterior 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 results exceeding risk screening values are provided in Exhibit 2 of the Brownfields Agreement. Soil Results from the February 2020 site assessment indicate arsenic was the only constituent detected above residential PSRGs in multiple samples at concentrations up to 2.6 mg/kg. Arsenic concentrations fell within the range detected in the site-specific background soil sample range of 1.3 mg/kg to 2.6 mg/kg. Soil sample laboratory results from January 2014 sampling activities indicate that 1,2,4- trimethylbenzene (110 mg/kg) and naphthalene (18 mg/kg) were detected above residential PSRGs in sample GP-9 collected at a depth of 11-13 feet bgs. In addition, laboratory results from the September 2000 site assessment indicated that naphthalene was detected above the residential PSRG at a concentration of 2.1 mg/kg in sample P-2 (12-16 feet bgs). Groundwater 6 Laboratory results from the February 2020 site assessment indicate that benzene, ethylbenzene, naphthalene, total xylenes, and 1-methylnaphthalene were detected in monitoring well TW-2 at concentrations above the NC 2L Groundwater Quality Standards. In addition, Benzo(a)anthracene, benzo(a)pyrene, benzo(b)fluoranthene, benzo(k)fluoranthene, dibenz(a,h)anthracene, bis(2-ethylhexyl)phthalate, hexachlorobenzene, and indeno(1,2,3-cd)pyrene were detected in TW-4 at concentrations above NC 2L Standards. Xylenes also exceeded residential groundwater VISLs at monitoring well TW-2. Previous environmental assessments conducted on the Brownfields Property in 2000, 2004, 2004, and 2015 for the purposes of defining groundwater impacts from the offsite UST incident indicated detections of petroleum hydrocarbon-related compounds in groundwater above their NC 2L Standards, including: ethylene dibromide (EDB), benzene, ethylbenzene, toluene, xylene, MTBE, naphthalene, 1,2,4-trimethylbenzene, 1,3,5-trimethylbenzene, and VPH C5-C22 aliphatics. Surface Water Surface water is not present at the Brownfields Property. Exterior Soil Gas Results from the February 2020 assessment indicated that VOCs were detected in each of the soil vapor samples; however, chloroform was the only compound detected at the Brownfields Property (SV-04) at a concentration slightly above its Residential SGSL. Laboratory results also indicated that trichloroethylene was not detected in soil vapor. Laboratory results from March 2021 generally confirmed that no VOCs were detected above SGSLs, including chloroform, which was potentially from a leaking water line. Trichloroethylene was detected in one vapor sample, 2021-SV-04, but below its Residential SGSL at a concentration of 1.3 micrograms per cubic meter- (µg/m3). Risk Calculations Risk calculations were performed using the NCDEQ Risk Calculator (DWM, January 2021). The samples used in the risk analysis included TW-2 (Groundwater), the highest soil concentrations detected site-wide, and the highest exterior soil gas concentrations site-wide. Historical environmental data generated prior to 2020 was not used in the groundwater risk calculations because the exterior soil gas and groundwater samples collected during the 2020 and 2021 sampling events near these historical sample locations indicated lower concentrations of petroleum-related compounds downgradient of the adjacent UST incident than had previously been detected as would be expected. The results from the NCDEQ Risk Calculator are provided in the following table. 7 Risk for Individual Pathways Output Form 1A Version Date: June 2021 Basis: May 2021 EPA RSL Table Site ID: 23070-19-060 Exposure Unit ID: Site Wide Soil Gas (2021), Soil (2020) and TMW-2 (Groundwater) Receptor Pathway Carcinogenic Risk Hazard Index Risk exceeded? Soil 3.8E-06 9.2E-02 NO Groundwater Use*1.7E-03 3.7E+01 YES Soil 8.7E-07 7.2E-03 NO Groundwater Use*4.5E-04 8.9E+00 YES Construction Worker Soil 1.4E-07 7.8E-02 NO Soil 2.1E-06 4.9E-02 NO Surface Water*NC NC NC Receptor Pathway Carcinogenic Risk Hazard Index Risk exceeded? Groundwater to Indoor Air 6.9E-05 3.5E+00 YES Soil Gas to Indoor Air 2.0E-06 5.0E-02 NO Indoor Air NC NC NC Groundwater to Indoor Air 1.6E-05 8.4E-01 NO Soil Gas to Indoor Air 1.5E-07 4.0E-03 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 Based on the results of the risk evaluation, although groundwater to indoor air vapor intrusion calculations exceed carcinogenic and noncancer risk thresholds for residential exposure scenarios, the soil gas to indoor air calculations do not. Risk calculator results indicate that the Residential Hazard Index for soil gas is less than 0.1. Groundwater is not expected to be encountered during construction. Further although historical groundwater sampling results indicated that high concentrations of petroleum-related contaminants were once detected at former monitoring well locations TW-2 (P-10) and MW-6, subsequent groundwater and soil vapor samples collected downgradient and in the vicinity of these locations (including soil vapor sample locations SV-02, SV- 03, SB-05, 2021-SV-03; and monitoring wells (TW-4, HHTW-4, MW-7) indicate that high concentrations of petroleum-related compounds comparable to levels detected 15-20 years earlier were not detected within the footprint of the proposed buildings. Therefore, vapor mitigation measures will not be required for the site. Risks due to exposure from potential contaminants in soils will be controlled through management practices identified in the Environmental Management Plan. Many of the soil samples collected prior to 2020 with identified exceedances of Residential PSRGs appear to have been collected at or below the water table. Elevated concentrations of petroleum-related compounds detected in groundwater will require a land use restriction prohibiting the use of groundwater; however, municipal water is available at the Brownfields Property, further minimizing the potential risks. An Environmental 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 8 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 (if necessary due to changed conditions), 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 Unit A vapor intrusion mitigation system is not required for the site based on recent data and risk calculations. Arsenic concentrations detected in soil are comparable to site background concentrations.