Public Works cleanup site — Restorical Research
King County Metro Riverton Ops Center
12400 E Marginal Way S, Tukwila, King County
Restorical Research
Preliminary Site-Specific Analysis

This property has a documented history as a public works and maintenance facility predating 1986. Historical insurance policies issued during those prior operations and through 1986 could recover the cleanup costs already paid.

This property served as a public works operations center with two 8,000-gallon single-walled steel underground storage tanks storing diesel fuel — a tank construction standard consistent with installation before 1988. A Phase I/II Environmental Site Assessment conducted by AGRA Earth & Environmental in November 1994 identified diesel-range petroleum contamination in groundwater, with total petroleum hydrocarbon concentrations in monitoring wells reaching 4,900 µg/L and 3,400 µg/L, both well above the MTCA Method A cleanup level of 500 µg/L. Independent remedial action was carried out from November 1994 through March 1998 under the Voluntary Cleanup Program, and Ecology issued a No Further Action determination on June 18, 1998. That history could support an insurance cost recovery claim against carriers who issued insurance policies 40+ years ago.

Former Use
Former Public Works
Address12400 E Marginal Way S, Tukwila, King County
Historical UsePublic Works
Est. Operating SincePre-1986
StatusNo Further Action
Contamination & Investigation
Site Assessment Summary
ContaminantsDiesel-range total petroleum hydrocarbons (TPH) detected in groundwater
Media ImpactedSoil, Groundwater
Regulatory ProgramMTCA — Voluntary Cleanup Program
Ecology Site #9602

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 single-walled steel diesel USTs at this facility were constructed to pre-1988 standards and were very likely installed before 1986, during the era when occurrence-based Commercial General Liability policies covered pollution claims without effective exclusion. The remediation costs incurred between 1994 and 1998 — site assessment, groundwater investigation, and cleanup of diesel contamination exceeding state standards by nearly tenfold — are the type of expenditures that historical CGL carriers may be obligated to reimburse. With a No Further Action determination now in hand, the full scope of cleanup costs is defined and recoverable.

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.