Remedial Investigations for Corrective Action Design
Petroleum Release to Weathered Bedrock in Denver:
LWS personnel conducted soil vapor extraction (SVE) and air sparge (AS) pilot testing to evaluate the air flow volumes and radius of influence for SVE/AS wells in the weathered bedrock. Data from the pilot test indicated variable conditions, resulting in a corrective action design that allowed for turning wells on/off across the site as needed to mitigate the petroleum impacts through a combination of SVE/AS and bio-attenuation.
Confined Animal Feeding Operation (CAFO) near Turpin, Oklahoma:
LWS personnel assisted legal counsel related to an allegation of unregulated releases from a CAFO that were alleged to have migrated through the unsaturated zone to the local ground water table and were moving laterally so that constituents of concern (COCs) were daylighting to surface drainages and becoming a surface discharge. LWS personnel conducted extensive engineering and field hydrogeologic investigations to demonstrate no evidence of the allegations. Based on the results of the investigations, the case was settled prior to going to trial.
Gasoline Contamination Adjacent to a Municipal Production Well:
A gasoline tank truck traveling along Highway 83 near Parker, Colorado overturned, spilling several thousand gallons of gasoline adjacent to the Cherry Creek alluvial aquifer and within several hundred feet of a municipal production well. LWS personnel designed and implemented a monitoring well network to assess the migration of gasoline in the alluvial aquifer to ensure that no contamination occurred to the adjacent water supply well. The well network was monitored frequently both during the clean-up program and until residual gasoline concentrations had been reduced to below maximum contaminant levels.
Confined Animal Feeding Operation (CAFO) in North Carolina:
LWS personnel assisted legal counsel in a case where it was alleged that a known effluent release from a CAFO caused surface water quality degradation in the Black River in North Carolina. LWS personnel conducted a field investigation, collecting both surface water flow and water quality data downstream of the known release and constructed a surface flow/water quality model based on the data collected to assess the potential water quality degradational effects. The results of the investigation indicated no measurable water quality degradation in the Black River and the case was settled prior to going to trial.