South Berwick radon mitigation — local context
South Berwick sits in York County, Maine, which the EPA places in Radon Zone 1 — its highest-potential category, where the predicted average indoor screening level exceeds the EPA's 4 pCi/L action level (EPA Map of Radon Zones). The risk is real here: Maine homes average 4.3 pCi/L versus 1.3 pCi/L nationally, and in southwestern Maine more than half of tested households show elevated levels (Maine Tracking Network / Maine CDC, via WGME 2024). The cause is local geology — uranium in Maine's granite bedrock decays into radon gas (Yang et al., Environmental Science & Technology, 2014). South Berwick is a 17th-century river-valley town on the Salmon Falls and Great Works rivers, full of pre-1800 homes over that bedrock (Wikipedia) — the classic radon-entry profile. 603 holds radon certification RMS-113966 and installs slab and crawl-space sub-membrane depressurization systems. Radon mitigation runs $900–$6,000 (most jobs $1,950–$2,250); the radon test is $50, credited toward the job if you proceed. See radon level testing.
What a recent customer said
Called to have Radon mitigation system installed. They were EXTREMELY professional, very reasonable, and quick to get the job done. The job was done right the first time too! If you want the white-glove treatment, then look no further. — William Sparks
Frequently asked questions
Does South Berwick, Maine need radon mitigation?
South Berwick is in York County, which the EPA places in Radon Zone 1 — its highest-potential category, where the predicted average indoor radon level exceeds the 4 pCi/L action level (EPA Map of Radon Zones). Maine homes average 4.3 pCi/L versus 1.3 pCi/L nationally, and in southwestern Maine more than half of tested households show elevated levels (Maine CDC / Maine Tracking Network). Test first, then mitigate if you're at or above 4 pCi/L.
Why do South Berwick homes have high radon?
It's the geology. South Berwick sits on granite-rich bedrock in the Salmon Falls and Great Works river valley, and uranium in Maine's granite decays into radon gas that seeps indoors (Yang et al., Environmental Science & Technology, 2014). The town's many pre-1800 homes — settled around 1631 — often sit on older foundations that give radon more entry points (Wikipedia).
What does radon mitigation cost in South Berwick, and is the test free?
603's radon mitigation runs $900–$6,000, with most jobs landing between $1,950 and $2,250. The radon test is $50 — not free — but it's credited toward the job if you proceed. 603 is radon-certified (RMS-113966) and installs both slab and crawl-space sub-membrane depressurization systems, which suits older South Berwick homes with dirt or fieldstone crawl spaces.