Industrial Facility Contamination
In 2013, Tioga began working as a sub-consultant for AECOM at an industrial site in Memphis, TN. AECOM was tasked with performing a subsurface investigation to address possible contamination at the property. Original Tioga work included the sampling of soil and previously installed groundwater monitoring wells. An area of concern on the property was excavated due to the location of underground storage tanks. Based on soil sampled during the excavation, Tioga advanced soil borings to delineate areas of contamination and a phased approach workplan was developed for the removal of contaminated soil at the site.
In March, 2015, Tioga participated in an indoor ambient air and sub-slab vapor assessment to determine possible areas of the property that would require detailed assessment. An additional vapor sampling assessment was performed at the property in May, 2015. Based on the results of these assessments, a workplan was drafted for a comprehensive vapor monitoring survey that was conducted in March, 2016 and consisted of the installation of approximately 60 sub-slab vapor monitoring points and concurrent indoor air samples.
In May, 2017, Tioga advanced 35 soil borings at the property. Soil samples were collected from the borings and analyzed by a portable gas chromatogram. Based on gas chromatogram and photoionization detector readings, soil samples were collected for laboratory analysis of volatile organic constituents, semi-volatile organic constituents, extractable petroleum hydrocarbons, priority pollutant metals, and pesticides depending on sample location. After soil boring advancement, the borings were converted into temporary monitoring wells.
Tioga personnel collected groundwater samples from 35 temporary monitoring wells in addition to 8 permanent monitoring wells previously installed at the site. Groundwater samples were collected using EPA low-flow sampling methods with a bladder pump. Groundwater samples were submitted for laboratory analysis of volatile organic constituents, semi-volatile organic constituents, extractable petroleum hydrocarbons, priority pollutant metals, and pesticides depending on sample location. Based on laboratory analytical results, additional field work including soil and groundwater sample collection will be performed at the site.