Senator Carper Votes Nay

The Senate Environment and Public Works Committee voted to send the nomination of Stephen L. Johnson as Environmental Protection Agency adminnistrator to the floor of the Senate. The vote was 17 to 1, with Tom Carper voting nay. Why? Carper is not known as a firebrand; he's one of the Senate's most moderate Democrats.
Senator Carper has offered an alternative to President Bush's "Clear Skies" legislation (which has failed to make it out of committee). The problem is that Carper has asked the EPA for analysis on his proposal, but has not had any response. Having voted nay, he is considering placing a "hold" on the nomination, which would then require 60 votes to come to the floor.
Senator Carper, in a prepared statement, said:

Repeatedly, I’ve asked the EPA to conduct a detailed, technical analysis of the economic and health benefits of my clean air proposal. I’ve been consistently denied, even though what I’m asking for is simple. The EPA has run a detailed health and cost estimate of the president’s Clear Skies plan. I want the same type of analysis completed on my bill because I believe it’s essential to help us craft a clean air compromise bill this year.

The compromise Carper has in mind would be based on his proposal, not the President's.