Yesterday's Colorado Matters has a nice show looking that issue. You can listen to it by clicking here. Their overview for the show is as follows :
Officials at the Colorado Department of Transportation are considering plans for reducing traffic along I-70 from Denver to Glenwood Springs. They expect to announce their first choice for a solution by the end of the year. Ryan Warner talks to CDOT engineer Brian Pinkerton and Idaho Springs Mayor Dennis Lundbery, who fears that widening the interstate—one of the plans under consideration—could take a toll on his community.Colorado Confidential took a look at this issue this past July. They don't focus on one solution. They do call for something to be done now rather than putting the issue off any longer.
There are groups like Mountains to Plains Transportation Solutions that advocate what their names says, building a train on the I-70 corridor. Trains Not Lanes is another one of these groups. Fight I-70 Congesting is yet another one of these groups.
The Colorado Department of Transportation has a web site dedicated to this issue. Beside review the PEIS and other information, you can sign up for their I70 mailling list.
If you know of other good sources on the subject, please share them.