I have read a couple diaries here and there every so often on abolishing the EPA. As a conservative I have no problem with the EPA. Well, actually I do, but I think something like the EPA is well within the bounds of the Constitution and is also appropriate in any industrialized nation.
The constitution allows Congress to pass laws "... for the common defense and general Welfare of the United States..." and "... to regulate Commerce with foreign Nations, and among the several States, and with the Indian Tribes..."
Let's now consider the environmental conditions that lead to the EPA. These include Cuyahoga river catching on fire, enough PCBs were dumped into the Hudson river that 40 years and major dredging efforts later the fish are still toxic to eat, batteries were disposed of by burning and releasing the fumes directly into the air. Tons and tons and tons of mercury were being dumped into the Great Lakes after which the pollutants cross international boundaries.
It is entirely within the bounds of the Federal government to limit the amount of pollutants that cross state borders and international borders (and so air pollution and water pollution). This must be Federal because the citizens of Louisiana cannot force states upstream to refrain from polluting the water. I believe it is also within the boundaries to set rules that promote the general welfare (not allowing companies to dump toxic waste on locations where it can seep into the water supply or affect food supplies). It may be in the general welfare to prevent cyanide from leaching into water tables, and if so Congress should have the authority to pass laws in those regards.
Does the EPA overreach? Absolutely. Is CO2 a pollutant? No (I cannot think of any rational definition of "pollution" that would include CO2). However, the EPA should absolutely not be abolished - it's bounds should simply be restricted to actual pollutants that are identified by congress either domestically or internationally. That is, EPA should be given a specific list of chemicals they are allowed to regulate, and any addition to that list should require a Congressional intervention. Then the EPA should be able to prevent factories in St. Paul MN from dumping cyanide into the Mississippi river (if cyanide is on the regulation list).