Tapcensus

Vinyl Chloride violations in Washington

102 active public water systems in Washington had a Vinyl Chloride violation in the past three years, 10 of them in the latest quarter of EPA's data. What Vinyl Chloride is and why it matters.

Health effects: Vinyl chloride is classified by EPA as a known human carcinogen (Group A). It is associated with a rare liver cancer called hepatic angiosarcoma, as well as liver and brain cancers. There is no safe threshold — any exposure carries some cancer risk. Workers in PVC manufacturing and communities near contaminated groundwater sites face the greatest risk.

Systems with a Vinyl Chloride violation

Latest quarter first, then largest first
SystemServesStatusRules violated, 3 yrUnresolved
Twin Pines Mobile Home Park
Okanogan County 		25 7 1
West Deer Lake #1
Island County 		24 5 0
About this data

A system is counted once if any of its violations in the past three years involved Vinyl Chloride, including monitoring and reporting lapses. Rules violated and status in the table are for the whole system, not Vinyl Chloride alone.

Source: the U.S. EPA's Enforcement and Compliance History Online system (ECHO), which publishes the federal Safe Drinking Water Information System. EPA's terms and values are shown as published. The Washington records are from EPA's data refresh of Oct 7, 2026; EPA refreshes this data quarterly, and states report to EPA with a lag of three to six months, so the newest violations may not appear yet.