Monday was the deadline to file suits over a federal green light given in January for the controversial $1.2 billion plan to sink a portion of I-70 in north Denver and expand the highway with new toll lanes between I-25 and Tower Road.

And opponents of the plan made their moves accordingly.

A group of residents who oppose the project filed a lawsuit Sunday against the Federal Highway Administration (FHWA) in the U.S. District Court in Denver and held a press conference Monday on the steps of the…