Closure activities completed by CEG included the following tasks:
- Prepared a closure plan in accordance to Chapter 600, Section 12.D of the Maine DEP'sChapter 600: Marine Oil Terminal Rules;
- Completed a piping survey to document the piping system layout, prior to removal activities and to document the termination points of piping left in place;
- Supervised the completion of test pits to define the extent of #6 fuel oil impact to the subsurface;
- Collected soil samples for onsite screening of volatile organic compounds and oil saturation;
- Submitted soil samples to the laboratory for analysis; and
- Prepared a facility closure report.
Based on the soil screening and oil saturation test results, approximately 890 tons of #6 fuel oil impacted soil was removed from around the tank and transported offsite to a licensed disposal facility. The excavation was backfilled using clean material from the containment dike around the former tank and was graded. Approximately 115 tons of #6 fuel oil impacted soil was also removed from the rail line for disposal
A total of four soil samples were also collected from the excavation near the tank for laboratory analysis of diesel range organics. The Maine DEP cleanup standard for diesel range organics in soil by laboratory analysis was 2,500 milligrams per kilogram (mg/kg). All of the samples collected had diesel range organics concentrations well below the Maine DEP cleanup standard.
A facility closure report was prepared by CEG and submitted to the Maine DEP. The report summarized methods and results of the tank removal activities and included a comprehensive piping survey that was completed by CEG to document the piping system layout, prior to removal activities and the termination points of piping left in place. The report also included certification from an independent engineer that the tank closure was conducted in accordance with the Maine DEP approved closure plan.
The Maine DEP approved facility closure in the spring of 2005, following review of the facility closure report prepared by CEG.