The EPA is responsible for preventing and detecting environmental crimes, informing the public of environmental enforcement, and setting and monitoring standards of air pollution, water pollution, hazardous wastes and chemicals. "It is difficult to construct a specific mission statement given its wide range of responsibilities." It is impossible to address every environmental crime adequately or efficiently if there is no specific mission statement to refer to. The EPA answers to various groups, competes for resources, and confronts a wide array of harms to the environment. All of these present challenges, including a lack of resources, its self-policing policy, and a broadly defined legislation that creates too much discretion for EPA officers.