No one will ever accuse New York State of acting precipitously in going after Exxon Mobil for the awful oil spill into Newtown Creek and under Greenpoint. A lawsuit to force a faster cleanup and to impose fines was finally filed yesterday. The spill is one of the worst ever in the United States, an estimated 17-30 million gallons. (The Exxon Valdez only spilled 11 million gallons.) Until the suit was filed, the cleanup had been conducted under agreements with the state that had led to a very slow cleanup of the mess. While much of the spill is bubbling around under industrial parts of Greenpoint, it has impacted residential areas and its exact boundaries aren’t even known. The suit would force a faster cleanup and impose millions of dollars in fines. BP, Chevron, KeySpan and Phelps Dodge (which operated a nearby copper smelter) are also named in the suit. The spill originated with an explosion in the 1950s that ruptured oil storage tanks; the Coast Guard “discovered” it in 1978.