Soil Subsurface Investigation – Bedford, NH
CommTank provided a limited subsurface investigation (LSSI) at a home in Bedford, NH. This customer wanted to ascertain if there was any petroleum contaminated soil in the vicinity of where an underground storage tank (UST) was thought to be previously located.
CommTank conducted a subsurface investigation under the patio in the back yard. A total of three soil borings were advanced to 8 feet below ground surface. The soil borings were advanced with a Geoprobe subsoil sampler equipped with 36-inch zero contamination sampling tubes and sealed with vinyl caps to prevent the loss of volatile and semi-volatile contaminants which might be present in the soil and an AMS rig. No UST was encountered during the advancement of the soil borings. Soil samples were collected at two-foot intervals in each boring. The soil samples were inspected for visual and olfactory evidence of contamination. Field screening was conducted on each soil sample using a RAE Systems MiniRAE photoionization detector (PID). Total Volatile Organic Vapors (TVOVs) ranging from 3.0 parts per million by volume (ppmv) to 9.0ppmv in soil boring SB1 were detected in the soil samples.
A soil sample from SB1 was submitted to ChemServe Environmental Analysts, a state-certified analytical laboratory for analysis of Volatile Organic Compounds (VOC), Polyaromatic Hydrocarbons (PAH), Total Petroleum Hydrocarbon (TPH) analysis. The laboratory results indicated all compounds were below the lab detection limits and the applicable New Hampshire Department of Environmental Services standards.
The location of the soil borings was determined by a ground penetrating radar survey. The assessment was limited to the location of the three soil borings. In addition, no air quality monitoring was performed or any non-virgin petroleum analysis of soil, surface water, or groundwater at this site.