22022_Pfister Dyes Decision Memorandum 20181015

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DECISION MEMORANDUM
DATE: October 15, 2018 FROM: Bill Schmithorst TO: Pfister Dyes and Chemical Project File
RE: Pfister Dyes and Chemical 4233 Trailer Drive Charlotte, Mecklenburg County BF # 22022-18-060
Based on the following information, it has been determined that the above referenced site, whose intended use is for no uses other than industrial, office, parking, and, subject to DEQ’s prior written approval, other commercial uses, can be made suitable for such uses.
Introduction: The Pfister Dyes and Chemical Brownfields Property contains one parcel (Tax ID No. 04505507) totaling 5.75 acres. The Brownfields Property contains one building totaling 19,000 square feet. The Brownfields Property is surrounded by land used for commercial,
light industrial and residential purposes. Redevelopment Plans: 4233 Trailer Drive, LLC intends to use the property for commercial, office, parking and light industrial purposes. Initial development plans are for the existing building to be
remodeled. The central and northern undeveloped portions of the property will potentially be developed in the future for the same intended use. Site History:
The Brownfields Property was undeveloped wooded and agricultural land as early as the
late 1930s. In approximately 1967, the southern portion of the Site was developed with an approximately 19,000-square foot (sq. ft.) warehouse building that was constructed for Pfister Dyes and Chemical (Pfister). Pfister utilized the facility for mixing, storage, and distribution of powdered dyes used in the textile industry until approximately 2017. The
central and northern portions of the Site have remained undeveloped wooded land.
According to the 2017 Phase II report (Geoscience Group, 2107), a release of unspecified material to a floor drain leading to the facility’s septic leach field was reported to the North Carolina Department of Environment and Natural Resources in 1994 (NCDEQ
Incident No. 12757). Soil samples were collected from the septic leach field and
laboratory results indicated that Total Petroleum Hydrocarbons (TPH) were detected. The septic system and leach fields were abandoned in 1994 and approximately 50 cubic yards of petroleum impacted soil was excavated from the leach field and spread on the undeveloped northern portion of the property to passively remediate the soils through
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land application with DEQ’s approval. Following abandonment of the septic leach field, two groundwater monitoring wells were installed in the former septic leach field area and
sampled. No VOC constituents were detected in the groundwater monitoring wells above NCAC 2L Groundwater Standards. The NCDEQ closed the incident with no further action in January 1995. Phase II environmental site assessments were conducted at the Brownfields Property in
2017 and 2018 for property due diligence purposes. In July 2017, a temporary groundwater monitoring well in an upgradient portion of the Brownfields Property was sampled to determine if the previous thallium detections in the May 2017 MW-1 and MW-2 groundwater samples were consistent with naturally occurring levels. Analytical results of the background groundwater sample indicated that thallium was not detected
above the laboratory reporting limit. In January 2018, four additional soil samples were collected near the trench drain in the former dye mixing room and submitted to a laboratory for the analysis of VOCs, SVOCs and RCRA metals. In addition, four shallow groundwater monitoring wells were installed
to evaluate previous detections of thallium in groundwater. Laboratory results indicated that no constituents were detected above Industrial/Commercial PSRGs. Results also indicated that thallium was not detected in any of the groundwater samples above NCAC 2L Standards.
In July 2018, two background soil samples and four groundwater samples were collected at the Brownfields Property. One additional shallow groundwater monitoring well, TMW-1, was installed downgradient from the former septic leach system and the onsite building. Soil samples were submitted to a laboratory for the analysis of RCRA metals and groundwater samples were analyzed for VOCs, SVOCs, RCRA metals, with the
exception of MW-3, which was only analyzed for VOCs. Laboratory results indicated that no soil constituents were detected above Industrial/Commercial PSRGs. In addition, no groundwater constituents were detected above NCAC 2L Standards.

Potential Receptors: Potential receptors: Groundwater users and construction workers. A receptor survey was conducted in July 2018. The area is served by a municipal water system. Four private water supply wells and one irrigation water supply well were located within 1,500 feet of
the site; however, none of the wells are located adjacent to the property. The
contaminants detected in groundwater at the property were detected at low concentrations and are unlikely to impact any of the identified wells. Contaminated Media:
DEQ has evaluated data collected from soil and groundwater at the subject property.
DEQ relies on the following data to base its conclusions regarding the subject property and its suitability for its intended reuse. Soil
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Subsurface soil samples were collected over multiple sampling events from beneath the production areas of the building, floor trenches, abandoned septic leach field, and former
soil land application area. Soil samples were analyzed for VOCs, SVOCs, and RCRA metals. Laboratory results indicated that arsenic was the only constituent detected above non-residential PSRGs. Arsenic was detected at similar concentrations to the background samples collected at the site.
Results from the Risk Calculator presented below show an exceedance of the Hazard Index of 1.0 for the Construction Worker pathway. This exceedance is due to the presence of manganese in soil at sample location HA-10. However, the manganese concentrations detected in soil at the site are similar to soil background concentrations.
Groundwater Seven groundwater monitoring wells were installed and sampled at the Brownfields Property during multiple environmental investigation. Groundwater samples were collected from monitoring wells and analyzed by a laboratory for VOCs, SVOCs, and RCRA metals. Laboratory results from a 2017 sampling event indicated that thallium was
detected at a concentration exceeding NCAC 2L Groundwater Standards in monitoring wells MW-1 and MW-2. No additional VOCs, SVOCs or metals were detected above NCAC 2L Groundwater Standards. An attempt was made to resample monitoring wells MW-1 and MW-2 to verify the presence of thallium, however, the wells were found to be dry and samples could not be collected. Four additional monitoring wells (MW-3 through
MW-6) were installed at the Brownfields Property in January 2018 and sampled for thallium. Laboratory results indicated that thallium was not detected above NCAC 2L Groundwater Standards. Risk Calculations
Risk Calculations were performed using Excel worksheets provided by Sandy Mort, NCDEQ Brownfields Toxicologist. Soil and groundwater samples with the highest combined concentrations of constituents were evaluated using the risk calculator. The risk calculations indicated the following based on available data from groundwater and
residual soil samples:

Risk Calculations
PRIMARY CALCULATORS
Receptor Pathway Carcinogenic
Risk
Hazard
Index
Risk
exceeded?
Non-
Residential Worker
Soil Combined Pathways 1.8E-05 4.7E-02 NO
Groundwater Combined Pathways 2.4E-07 1.0E+00 NO
Construction Worker Soil Combined Pathways 0.0E+00 5.7E+00 YES
VAPOR INTRUSION CALCULATORS
Receptor Pathway Carcinogenic Hazard Risk
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Red shading LICR> 1E-04 or HI> 1. HI = Hazard Index
Based on the evaluation of risk from constituents detected in soil and groundwater, risks from constituents detected at the site are within acceptable limits for the proposed use. Site construction work involving soil excavation and grading will be conducted under an Environmental Management Plan to protect site construction workers. Final grade soil sampling will be conducted in the central and northern portions of the property once
those areas are developed. Required Land Use Restrictions: Based on the site-specific data provided to the Brownfield program, the site is suitable for the proposed reuses as long as the agreed upon land use restrictions in the BFA are
abided by. 1. No use other than for industrial, commercial, office, and parking 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 protocol is followed. 5. EMP 6. Access to Brownfields Property for environmental assessment. 7. NBP reference in deed.
8. No contaminants on property except for de minimis amounts, fluid in vehicles, fuels for generators/equipment.
Risk Index exceeded?
Non-Residential Worker
Groundwater to Indoor Air 9.8E-08 3.3E-02 NO