Heating Oil Tank cleanup site — Restorical Research
Forest Ave SE Residence
Mercer Island, King County
Restorical Research
Preliminary Site-Specific Analysis

This property has a documented history as a property with a heating oil tank going back to 1960. Historical insurance policies issued during those prior operations and through 1986 could recover the cleanup costs already paid.

This Mercer Island property operated as a private residence from the early 1960s, with two 600-gallon underground storage tanks supplying heating oil to the original structure. A leak from one of those tanks was discovered in 2003 during tank removal, at which point soil contamination from petroleum hydrocarbons was confirmed. Cleanup consisted of excavating the contaminated soil and removing both tanks; post-excavation sampling confirmed the complete absence of petroleum hydrocarbons, and the site received a No Further Action determination. That history could support an insurance cost recovery claim against carriers who issued insurance policies 40+ years ago.

Former Use
Former Heating Oil Tank
AddressMercer Island, King County
Historical UseHeating Oil Tank
Est. Operating Since1960
StatusNo Further Action
Contamination & Investigation
Site Assessment Summary
ContaminantsPetroleum hydrocarbons from a leaking 600-gallon heating oil UST detected in soil
Media ImpactedSoil, Groundwater, Surface Water
Regulatory ProgramMTCA — Standard Cleanup
Ecology Site #2594

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.

The heating oil tanks at this residence were installed and in active service by the early 1960s — more than two decades before 1986, when occurrence-based Commercial General Liability policies were standard and carried no effective pollution exclusion. Although the leak was not discovered until 2003, the contamination itself was a product of those pre-1986 tank operations, not a recent incident. Historical carriers whose CGL policies were in force during the decades those tanks were in service may be obligated to fund the excavation and remediation costs that ultimately brought the site to its No Further Action resolution.

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

Task 1 — Research and Analysis
Restorical searches for viable historical insurance policies, researches the site history, analyzes the contamination impacts, and underwrites potential coverage — including a proprietary trigger analysis. At the end of Task 1, we provide a clear yes or no on whether a successful cost recovery is possible, along with a strategy and recommendation specific to your situation, even if you are not the policyholder.
Task 2 — Cost Recovery
When Task 1 confirms viable coverage, Restorical works with your legal counsel to tender the claim and negotiate recovery of costs already incurred. Restorical's forensic accounting team re-establishes and documents past cleanup expenditures, managing the claim process to ensure the insurance companies fulfill their obligation in a timely manner.

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This analysis is preliminary and based on publicly available records. Restorical Research is not a law firm and does not provide legal advice.