Heating Oil Tank cleanup site — Restorical Research
Mossman Property
3461 East Lake Sammamish Shore Ln NE, Sammamish, 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 1949. Historical insurance policies issued during operations at this property and through 1986 could fund a cleanup — and recover costs already spent.

This residential property was constructed in 1949 with a 500-gallon heating-oil underground storage tank installed at the same time and used for home heating continuously until October 2012, when the owner converted to natural gas and abandoned the UST in place. Cleanup activities under the Voluntary Cleanup Program have included tank removal, excavation of contaminated soil, LNAPL recovery, and in-situ groundwater treatment using oxygen-releasing compounds and monitored natural attenuation; multi-year monitoring is expected to continue. The property remains in active residential use with natural gas heating. That history could support an insurance cost recovery claim against carriers who issued insurance policies 40+ years ago.

Former Use
Former Heating Oil Tank
Address3461 East Lake Sammamish Shore Ln NE, Sammamish, King County
Historical UseHeating Oil Tank
Est. Operating Since1949
StatusCleanup Started
Contamination & Investigation
Site Assessment Summary
ContaminantsPetroleum hydrocarbons (heating oil / TPH) and LNAPL detected in soil and groundwater
Media ImpactedSoil, Groundwater, Surface Water, Air
Regulatory ProgramMTCA — Voluntary Cleanup Program
Ecology Site #12703

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 UST at this property was installed and operated for more than three decades before 1986, a period during which occurrence-based Commercial General Liability policies had no effective pollution exclusion under Washington law. Those historical carriers may be obligated both to recover costs already incurred — tank removal, soil excavation, and groundwater treatment to date — and to fund the anticipated years of ongoing monitoring and additional remediation that the Voluntary Cleanup Program work plan calls for.

Restorical's role is to locate viable historical policies, determine whether a successful coverage claim is possible, and assist our clients and their legal counsel to obtain insurance coverage. Restorical then manages the claim, including accounting, to ensure the cleanup is funded in a timely manner.

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 — Coverage and Funding
When Task 1 confirms viable coverage, Restorical works with your legal counsel to tender the claim, negotiate and secure insurance coverage. Restorical will manage the ongoing claim process, including accounting to ensure the insurance companies are funding your remediation 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.