Mill Creek Environmental was approached to perform a limited site investigation (LSI) on a closed manufacturing facility in northern Georgia. The scope of this investigation was directed specifically to address the potential for soil or groundwater contamination resulting from the historic industrial activities conducted at the subject property from the prior tenant. The property consisting of over 5 acres, including a 35,000 square foot warehouse/office.
MCE provided the following due diligence in this phase 2 (LSI) site assessment:
- A truck-mounted drilling rig equipped with direct-push technology was used for multiple direct-push soil borings collecting continuous soil samples from each boring
- Headspace vapor analysis was conducted on soil samples from each borehole at 2-foot intervals to determine if volatile organic vapors were present
- Soil and groundwater samples were collected from select soil borings and submitted for laboratory analysis
The subject property was identified in the Georgia Tier 2 database. The Georgia Tier 2 database is a list maintained by the Georgia Department of Natural Resources (DNR) Environmental Protection Division (EPD). This database is a list of facilities in the state that manufacture or store hazardous material and submit a chemical inventory report. It reported the storage and use of 20,000-gallons of chlorine bleach. No spills, leaks, or violations were reported in the environmental databases regarding the storage of hazardous material at the subject property but the future buyer wanted to be certain that no ground and groundwater contamination had occurred.
Soil boring locations were chosen based on historic use of the property, topography, and marked underground utilities. Below are examples boring location rationale executed on-site:
- Assess conditions of locations where heavy equipment was previously located in the interior of the building. Ground cover at this location was concrete.
- Assess conditions in the location of a sump/drain filled with concrete on the interior of the building.
- Assess conditions on near the trench drain on the interior of the subject property.
- Assess conditions on near the trench drains on the interior of the subject property.
- Assess conditions near a bulk chemical storage area in the interior of the building.
- Assess conditions in a chemical storage/mixing room on in the interior of the building.
- Assess conditions around the exterior of the building and property.
Continuous soil samples were collected from each soil boring with a 4-foot macrocore sampler and polyethylene liners. A headspace vapor screening for volatile organic compounds (VOCs) was conducted on soil samples at two-foot intervals using a photo-ionization detector (PID). Multiple soil samples were collected for laboratory analysis based on the results of the headspace vapor screening. Each soil sample was analyzed for VOCs by EPA SW846 Method 8260B and chromium by EPA SW846 Method 6010C.
Groundwater was encountered in various soil borings at depths ranging from approximately 15-20 feet bgs. Upon sufficient advancement into groundwater, a Screen Point 22 groundwater sampler attached to 3/8 inch polyethylene tubing was lowered within a slotted stainless steel screen deployed in the bottom of the bore hole. Groundwater samples were collected from these locations using a peristaltic pump to collect water samples directly into laboratory provided containers. The groundwater samples were analyzed for VOCs and dissolved chromium by the method listed above.
Laboratory analytical data indicated that chromium was detected in soil samples at concentrations ranging from 17.9 milligrams per kilogram (mg/kg) to 29.6 mg/kg. These concentrations are below the Georgia Hazardous Sites Response Act (HSRA) Appendix I Notification Concentration (NC) for chromium. Acetone was detected in some of the soil samples at concentrations below the HSRA App I NC for acetone.
Laboratory analytical data indicated that no VOC compounds were detected at concentrations above laboratory reporting limits in any of the groundwater samples analyzed. The laboratory analytical data indicated that dissolved chromium was not detected at concentrations above laboratory reporting limits in any of the groundwater samples.
CONCLUSIONS AND RECOMMENDATIONS
Based on the results of the LSI, soil and groundwater at the subject property do not appear to have been adversely impacted by historic uses of the property. MCE recommends no further investigation at this time and the buyer was able to move forward to complete the purchase of the property.