As a rule, the details of massive transportation bills in Congress are dull enough to make reasonable folks' eyes glaze over. But the one pending on Capitol Hill right now is not just another transportation bill.

Secretary of Transportation Ray LaHood, a former Republican congressman, recently explained, "It hollows out our No. 1 priority, which is safety, and frankly, it hollows out the guts of the transportation efforts that we've been about for the last three years. It's the worst transportation bill I've ever seen during 35 years of public service."

A New York Times editorial called the legislation "uniquely terrible."

* It would make financing for mass transit much less certain, and more vulnerable, by ending a 30-year agreement that guaranteed mass transit a one-fifth share of the fuel taxes and other user fees in the highway trust fund. Instead it would compete annually with other programs.

* It would open nearly all of America's coastal waters to oil and gas drilling, including environmentally fragile areas that have long been off limits. The ostensible purpose is to raise revenue to help make up what has become an annual shortfall for transportation financing. But it is really just one more attempt to promote the Republicans' drill-now-drill-everywhere agenda and the interests of their industry patrons.

* It would demolish significant environmental protections by imposing arbitrary deadlines on legally mandated environmental reviews of proposed road and highway projects, and by ceding to state highway agencies the authority to decide whether such reviews should occur.

That's a good summary, but it actually gets worse. The transportation bill also undermines mass transit, guts programs intended to improve biking and walking safety, opens Alaska's Arctic National Wildlife Refuge to drilling, and appears to have been written in part by oil-industry lobbyists.

The editorial board members of the Los Angeles Times said they thought their "capacity to be surprised by [Congress'] irresponsible gamesmanship" had been diminished, "and yet, we still can't help but be awe-struck by the mess the House of Representatives is preparing to make of the federal transportation bill."

Yesterday, the White House said in the unlikely event the bill passes both chambers, President Obama would veto it.

The next question is what House Speaker John Boehner (R-Ohio) intends to do about it.

Boehner allowed this monstrosity to come together, but earlier this week, he came to the realization that just about everyone, including most his own caucus, just couldn't stomach the bill. As of yesterday, the Speaker, as he's done before, started scrambling to compensate for his poor management skills and weak position.

Speaker John Boehner is scrapping plans to pursue his signature transportation and energy package as one large measure and will instead break it into three smaller pieces, a move GOP aides said is aimed at overcoming internal Republican opposition. [...]

[P]rivately, GOP aides said leadership had come to terms with the fact that parochial divisions within the Republican Conference, united Democratic opposition and a conservative faction opposed to federal highway spending had made the measure politically unwieldy.

According to a senior aide familiar with the decision, Boehner's bill -- which had originally linked transportation spending with energy production revenues -- will now be separated into an energy bill, a stand-alone transportation measure and a package of ways to pay for the overall package.

Whether this improves the odds of success remains to be seen. On top of the opposition from Democrats, Republicans are fighting amongst themselves on everything from ports to drilling to anti-union provisions. One GOP aide told Roll Call the intra-party divisions are "a mess."

Update: The vote on this bill that had been slated for this week has been delayed. Brad Plumer has more on the fight.