The Exxon Valdez disaster is certainly the most notorious oil spill in the United States — a single, terrible accident that poured 11 million gallons of crude oil into Prince William Sound 1989, causing grievous damage to Alaska’s waters and beyond. But it is not the largest. In terms of volume it cannot match the steady seepage of oil into Newtown Creek, the polluted waterway that separates Brooklyn from Queens.

The Newtown Creek spill has not received anywhere near the response that followed the Valdez incident. The cleanup has been haphazard and ineffective, hampered by weak enforcement, and residents have been left in the dark about potential health effects.

A report this month from the Environmental Protection Agency suggested that the Newtown spill may be twice as large as first believed — some 30 million gallons, nearly three times the size of the Alaska spill. It has polluted the 4-mile strip of waterway and some 55 residential and commercial acres around it, gathering in subsurface reservoirs, mixing with groundwater, creating toxic vapors and and seeping, slowly but inexorably, into the creek. One major concern is the reported leakage of chemical vapor into homes.

The report was welcome, but far too long in coming. And it did not go far enough. Representatives Nydia Velazquez and Anthony Weiner, two members of Congress whose districts are affected, and who fought for the study, were understandably disappointed with the results. Both lawmakers are studying ways to speed the cleanup and assess health risks.