MassDEP Chapter 21E: What Middlesex County Homeowners Need to Know About Oil Tank Removal

If your home was built or heated with oil before the 1990s, there's a real chance an underground storage tank (UST) is still buried on the property — sometimes with the current owner unaware it's there. Here's what matters if that's your situation.

Why this comes up so often during home sales

Many Massachusetts homes converted from oil heat to gas decades ago, and it wasn't always standard practice to remove the old underground tank — it was simply abandoned in place. Buyers' lenders and attorneys increasingly ask for a "tank sweep" (a scan to confirm whether a UST is present) before closing, because an undiscovered leaking tank becomes the new owner's liability.

What is Chapter 21E?

Massachusetts General Law Chapter 21E is the state's hazardous waste and environmental cleanup statute. It's the legal framework that governs liability and cleanup requirements when contamination — including from a leaking oil tank — is discovered on a property. It's administered by MassDEP.

What happens if a tank is found

If a tank sweep confirms a UST is present, the typical next step is professional removal, which includes safely emptying and extracting the tank and testing the surrounding soil for contamination. If soil contamination is found, further remediation may be required under MassDEP guidelines before the property can be considered clear for sale or refinancing.

What removal typically involves

A licensed tank removal contractor excavates around the tank, removes any remaining oil and sludge, extracts the tank itself, and takes soil samples from the excavation area. If samples come back clean, you typically receive documentation confirming no contamination — valuable to have on file for future sale or refinancing. If contamination is found, scope and cost expand from there.

Don't wait for a sale to find out

If you suspect an old tank might still be buried on your property — an unexplained pipe stub near the foundation, an old fill cap in the yard, or heating records that mention oil — getting a tank sweep now, on your own timeline, is far less stressful than discovering it mid-transaction.

This is general information, not legal advice. Consult a licensed tank removal contractor and, if contamination is suspected, a Massachusetts environmental attorney or Licensed Site Professional.