It’s no secret that the Environmental Protection Agency (EPA) works closely with radical environmental activists, but new emails recently released by U.S. Senator David Vitter (R-LA) and U.S. Representative Darrell Issa (R-CA) show just how much the EPA has relied on environmentalists at the Natural Resource Defense Council (NRDC) for help.

In one email, EPA Administrator Gina McCarthy was fawning to officials at the NRDC over their role in prompting the EPA’s proposed carbon rule for existing power plants, noting the “success is yours as much as mine.”

According to a July New York Times article, McCarthy is justified in her praise; the EPA used a plan put forth by the NRDC “as a blueprint” in crafting its proposed rule. The article deemed the rule “a remarkable victory” for the NRDC, a group whose “reach extends from the big donors of Wall Street to the elite of Hollywood (Leonardo DiCaprio and Robert Redford are on its board) to the far corners of the Environmental Protection Agency.” While the rule may be a victory for the NRDC, it will likely be a disaster for the American public.

As we have explained before, implementing the EPA’s climate rule would cripple the coal industry, cause job losses, and impose massive compliance costs on states and energy producers—costs that would then be passed on to the consumer via higher energy bills. In fact, a recent EPA report estimates that adoption of its rule would impose compliance costs between $5.4 and $7.4 billion annually by 2020 and up to $8.8 billion annually by 2030, making it one of the costliest regulations in U.S. history.

Despite the great cost, the rule would provide little environmental benefit. In fact, the EPA’s own data indicates that implementation of this rule would only decrease global carbon emissions by less than one percent.

So, why would the EPA propose a rule that would achieve so little at such a great cost? Perhaps because the EPA cares more about furthering the radical agenda of activists such as the NRDC than the economic impact of their plan on the average American.