SCOPE OF WORK: Site/risk assessment; operation, maintenance, and monitoring activities; and LSP services
The site, situated between a river, a 110-year old granite bridge, a public right-of-way, and a railroad, was historically utilized for the bulk storage of #6 fuel oil for paper manufacturing. The source of the #6 fuel oil release was a former underground storage tank (UST).
Omni Environmental Group conducted a comprehensive site assessment program to update the conceptual site model and identify viable remedial action alternatives. This included installation of numerous soil borings; collection of soil, groundwater, surface water, sediment, sterilized-gauze wipe, and non-aqueous phase liquid (NAPL) samples; and analysis of samples for chemical and physical properties including petroleum hydrocarbons, residual saturation, viscosity, core photography, ultraviolet florescence, and laser induced fluorescence.
Our data redefined the mass, mobility, and recoverability of site NAPL and allowed us to identify the regulatory framework, remedial design, remedial costs, and monitoring requirements necessary to achieve regulatory closure.
Omni Environmental Group also provided Licensed Site Professional (LSP) services and designed the shoring system to facilitate remediation and long-term mitigation. Over a nine-month timeframe, we provided field oversight and direction for the following:
- Overhead utility relocation and underground utility stabilization and monitoring
- Installation of a comprehensive shoring system over a 50-foot by 100-foot area
- Elevation, vibration and displacement monitoring
- Excavation of more than 4,785 tons of contaminated soil to a depth of 30 feet
- Removal of greater than 2,900 gallons of NAPL and oily liquids
- Treatment of more than 865,000 gallons of remedial wastewater
- Backfilling and compaction
- Site stabilization and restoration activities
As a result of the remedial actions, the vast majority of contaminated soil and NAPL have been removed from the site and migration of oil into the river has been eliminated.
Omni Environmental Group is continuing to provide post-remedial monitoring and sampling to meet Phase V Remedy Operation Status and NAPL performance standards and support the submission of an Activity and Use Limitation and a Permanent Solution Statement with Conditions to close the environmental case.