This property has a documented history as a property with a heating oil tank predating 1986. Historical insurance policies issued during those prior operations and through 1986 could recover the cleanup costs already paid.
This residential property in Oak Harbor was the site of an underground heating oil tank located along the west side of the residence owned by Gwen Diamond, which was suspected of leaking prior to 2006. Cleanup consisted of removing the tank in April 2007 and excavating contaminated soil, after which clearance sampling of both soil and water confirmed that remaining contamination levels fell below applicable cleanup standards. Washington State Ecology issued a No Further Action recommendation following the completed remediation. That history could support an insurance cost recovery claim against carriers who issued insurance policies 40+ years ago.
Why Historical Insurance Policies May Be Accessible
Pre-1986 Commercial General Liability (CGL) policies were occurrence-based and did not contain an effective pollution exclusion in Washington. If contamination occurred while those policies were active, those historical insurance carriers may still have a legal obligation to fund the cleanup costs, even if the business closed or the property changed hands.
A residential heating oil tank that was suspected of leaking prior to 2006 and whose removal was performed in 2007 almost certainly predates 1986 — the year occurrence-based Commercial General Liability policies began carrying effective pollution exclusions in Washington. The contamination here reflects the kind of slow, long-term release from a historical tank that pre-1986 CGL policies were written to address, not a sudden post-policy accident. The documented remediation costs for tank removal, soil excavation, and clearance sampling represent expenditures that historical carriers whose policies were in effect during the tank's operational life may be obligated to recover.
Restorical's role is to locate viable historical policies, determine whether a successful cost recovery claim is possible, and assist our clients and their legal counsel to obtain insurance coverage for costs already incurred. Restorical's forensic accounting team works to re-establish and document past cleanup expenditures, ensuring the strongest possible basis for recovery.
Recovering Costs from an Older Cleanup
If this site reached No Further Action years ago, the original cleanup expenditures may be difficult to reconstruct. Restorical's forensic accounting team specializes in re-establishing and documenting past cleanup costs — even decades later — to build the strongest possible basis for an insurance recovery claim.
What We Look For
- Historical insurance policies (pre-1986)
- Policy numbers, carrier names, and coverage periods
- Connection between contamination timing and policy period
- Evidence linking cleanup obligation to insured activity
What We Deliver
- Historical Coverage Chart
- Trigger Analysis & Property/Policy Nexus
- Coverage strategy with recommendations
- Insurance funding for your remediation
- Claims Management & Forensic Accounting
The Restorical Proven Process
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Contact UsThis analysis is preliminary and based on publicly available records. Restorical Research is not a law firm and does not provide legal advice.


