Chevron’s got some cleaning-up to do in the city’s Lamond-Riggs neighborhood, according to the Environmental Protection Agency (EPA). The agency released an order yesterday requiring the oil giant to take several steps to remediate a contaminated gas plume that leaked over time from a Chevron station in Chillium, Md., across the District line this quiet neighborhood in Northeast.

What can a gas plume do to a nice neighborhood like this? Well, in the words of the EPA, the threat is something called “subsurface vapor intrusion,” a term that figures big in a big EPA document on the mess.

Upon checking for subsurface vapor intrusion in Lamond-Riggs homes, the agency concluded that “there is elevation in benzene and MTBE vapor concentrations” in homes above the plume. In other words, Chevron’s plume has made it to the living room.

The EPA is requiring Chevron to take five steps that include expanding the “existing remediation system” and installing “individual vapor mitigations sytems” but that amount to a larger fiat: Clean this shit up!