State Implementation Plan

State Implementation Plan in the United States

State Implementation Plan (SIP) in Environmental Law

A state plan for regulating air pollution required by the Clean Air Act to ensure that states meet the National Ambient Air Quality Standards. The Environmental Protection Agency (EPA) establishes limits for air pollutants that it determines must be controlled to protect human health and the environment. States are then required to prepare a state implementation plan outlining how the state will achieve the standards. State implementation plans must be at least as stringent as any part of the statute or any regulations the EPA has published. The state must have legislative authority to handle the administrative aspects of the air control program, and it must have the right to enforce its law.

Over the past twenty years or so, guidance has become more detailed on what must be included in the SIP. At first the guidance came primarily from the EPA, but Congress stepped in in 1990 when it amended the Clean Air Act, and requirements can be found both in regulations and the statute itself.

After the SIP is prepared, it must be submitted to the EPA, which will decide whether it meets the conditions for approval. The EPA may approve or disapprove the SIP; it may approve only part of the state plan, disapprove part, or request further revisions. Until it is approved by the EPA, it is state law only and can only be enforced by the state. After approval, it becomes federal law as well, and either the EPA or the state can enforce it. If the state involved does not submit an approvable plan within the time specified by the EPA or Congress, a federal implementation plan will be prepared by the EPA.

States may revise their SIPs as they wish, but any changes must be submitted to the EPA. The EPA has power to force amendments to the SIP if it decides that the plan is no longer adequate or does not include necessary changes reflecting federal law. This action by the EPA is labeled an SIP call. If the EPA issues regulations for a newly listed pollutant, the states must revise their state implementation plans to incorporate the new criteria. Congress may also specify as it did in 1990 that amendments to the SIPs must be made to conform with the statute.

Even though a state cannot have a SIP that allows more air pollution than federal law does, it is permitted to include measures that will result in better control of air pollution. Most SIPs tend to follow federal law, though, sometimes by incorporating federal regulations almost verbatim. However, a state may choose to go beyond those standards.
Based on “Environment and the Law. A Dictionary”.

State Implementation Plan: Open and Free Legal Research of US Law

Federal Primary Materials

The U.S. federal government system consists of executive, legislative, and judicial branches, each of which creates information that can be the subject of legal research about State Implementation Plan. This part provides references, in relation to State Implementation Plan, to the legislative process, the federal judiciary, and the primary sources of federal law (cases, statutes, and regulations).

Federal primary materials about State Implementation Plan by content types:

Laws and Regulations

US Constitution
Federal Statutory Codes and Legislation

Federal Case Law and Court Materials

U.S. Courts of Appeals
United States courts of appeals, inclouding bankruptcy courts and bankcruptcy appellate panels:

Federal Administrative Materials and Resources

Presidential Materials

Materials that emanate from the President’s lawmaking function include executive orders for officers in departments and agencies and proclamations for announcing ceremonial or commemorative policies. Presidential materials available include:

Executive Materials

Federal Legislative History Materials

Legislative history traces the legislative process of a particular bill (about State Implementation Plan and other subjects) for the main purpose of determining the legislators’ intent behind the enactment of a law to explain or clarify ambiguities in the language or the perceived meaning of that law (about State Implementation Plan or other topics), or locating the current status of a bill and monitoring its progress.

State Administrative Materials and Resources

State regulations are rules and procedures promulgated by state agencies (which may apply to State Implementation Plan and other topics); they are a binding source of law. In addition to promulgating regulations, state administrative boards and agencies often have judicial or quasi-judicial authority and may issue administrative decisions affecting State Implementation Plan. Finding these decisions can be challenging. In many cases, researchers about State Implementation Plan should check state agency web sites for their regulations, decisions, forms, and other information of interest.

State rules and regulations are found in codes of regulations and administrative codes (official compilation of all rules and regulations, organized by subject matter). Search here:

State opinions of the Attorney General (official written advisory opinions on issues of state law related to State Implementation Plan when formerly requested by a designated government officer):

Tools and Forms

Law in Other Regions

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