Clearer skies through NOx legislation, smog levels down in East
In 1998, the Clinton administration implemented a market-style pollutant credit trading system for the 19 states which was expanded under the Bush administration. EPA administrator Stephen Johnson said that under the market system, the large, most problematic facilities were the first ones to install new pollution control equipment.
The dramatic results seen here for reduced levels of NOx are particularly promising for California's new bill that aims do the same for greenhouse gas emissions which employs a similar credit trading system.
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