Public Works cleanup site — Restorical Research
Kent Sewage Lagoons
Kent, King County
Restorical Research
Preliminary Site-Specific Analysis

This property has a documented history as a public works and maintenance facility going back to 1964. Historical insurance policies issued during those prior operations and through 1986 could fund a cleanup — and recover costs already spent.

The Kent Sewage Lagoons were constructed by the City of Kent near the Green River beginning in 1964 — the North Lagoon that year, with additional lagoons added in 1968 — and operated as a municipal wastewater treatment facility until 1973. The site is enrolled in the Voluntary Cleanup Program; planned remediation includes excavation of lagoon sludges, sediment, the lagoon liner, and underlying soils as part of a proposed stormwater detention and wildlife habitat enhancement project. Groundwater monitoring has also been conducted at the property. That history could support an insurance cost recovery claim against carriers who issued insurance policies 40+ years ago.

Former Use
Former Public Works
AddressKent, King County
Historical UsePublic Works
Est. Operating Since1964
StatusCleanup Started
Contamination & Investigation
Site Assessment Summary
ContaminantsLagoon sludges and contaminated sediments from former municipal wastewater treatment operations in soil and groundwater
Media ImpactedSoil, Groundwater, Surface Water
Regulatory ProgramMTCA — Voluntary Cleanup Program
Ecology Site #1125

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.

Municipal wastewater operations at this site ran from 1964 through 1973, placing the facility's entire active period more than a decade before 1986, when occurrence-based Commercial General Liability policies were the industry standard and carried no effective pollution exclusion. The contamination now requiring excavation and remediation — lagoon sludges and impacted underlying soils — is a direct product of those historical operations, and the City of Kent, as the operator of record throughout that window, may have held CGL coverage subject to those older policy terms. The documented cleanup expenditures — lagoon sludge and liner removal, soil excavation, and long-term groundwater monitoring — represent costs that historical carriers may be obligated both to recover and to fund as remediation proceeds.

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.

Ready to learn more?

Contact Us

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