The EPA has its headquarters in Washington, D.C., regional offices for each of the agency's ten regions, and 27 laboratories. The agency conducts environmental assessment, research, and education. It has the responsibility of maintaining and enforcing national standards under a variety of environmental laws, in consultation with state, tribal, and local governments. It delegates some permitting, monitoring, and enforcement responsibility to U.S. states and the federally recognized tribes. EPA enforcement powers include fines, sanctions, and other measures. The agency also works with industries and all levels of government in a wide variety of voluntary pollution prevention programs and energy conservation efforts.
In 2018, the agency had 14,172 full-time employees. More than half of EPA's employees are engineers, scientists, and environmental protection specialists; other employees include legal, public affairs, financial, and information technologists. In 2017 the Trump administration proposed a 31% cut to the EPA's budget to $5.7 billion from $8.1 billion and to eliminate a quarter of the agency jobs. However, this cut was not approved by Congress.
The Environmental Protection Agency can only act under statutes, which are the authority of laws passed by Congress. Congress must approve the statute and they also have the power to authorize or prohibit certain actions, which the EPA has to implement and enforce. Appropriations statutes authorize how much money the agency can spend each year to carry out the approved statutes. The Environmental Protection Agency has the power to issue regulations. A regulation is a standard or rule written by the agency to interpret the statute, apply it in situations and enforce it. Congress allows the EPA to write regulations in order to solve a problem, but the agency must include a rationale of why the regulations need to be implemented. The regulations can be challenged by the Courts, where the regulation is overruled or confirmed. Many public health and environmental groups advocate for the agency and believe that it is creating a better world. Other critics believe that the agency commits government overreach by adding unnecessary regulations on business and property owners.
Beginning in the late 1950s and through the 1960s, Congress reacted to increasing public concern about the impact that human activity could have on the environment. Senator James E. Murray introduced a bill, the Resources and Conservation Act (RCA) of 1959, in the 86th Congress. The 1962 publication of Silent Spring by Rachel Carson alerted the public about the detrimental effects on the environment of the indiscriminate use of pesticides.
In the years following, similar bills were introduced and hearings were held to discuss the state of the environment and Congress's potential responses. In 1968, a joint House–Senate colloquium was convened by the chairmen of the Senate Committee on Interior and Insular Affairs, Senator Henry M. Jackson, and the House Committee on Science and Astronautics, Representative George Miller, to discuss the need for and means of implementing a national environmental policy. In the colloquium, some members of Congress expressed a continuing concern over federal agency actions affecting the environment.
The National Environmental Policy Act of 1969 (NEPA) was modeled on the Resources and Conservation Act of 1959 (RCA). RCA would have established a Council on Environmental Quality in the office of the President, declared a national environmental policy, and required the preparation of an annual environmental report.
President Nixon signed NEPA into law on January 1, 1970. The law created the Council on Environmental Quality (CEQ) in the Executive Office of the President. NEPA required that a detailed statement of environmental impacts be prepared for all major federal actions significantly affecting the environment. The "detailed statement" would ultimately be referred to as an environmental impact statement (EIS).