The Cross-State Air Pollution Rule (CSAPR) is a rule by the

United States Environmental Protection Agency The Environmental Protection Agency (EPA) is an independent agency of the United States government tasked with environmental protection matters. President Richard Nixon proposed the establishment of EPA on July 9, 1970; it began operation on De ...

(EPA) that requires member states of the

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

to reduce power plant emissions that contribute to

ozone Ozone () (or trioxygen) is an Inorganic compound, inorganic molecule with the chemical formula . It is a pale blue gas with a distinctively pungent smell. It is an allotrope of oxygen that is much less stable than the diatomic allotrope , break ...

and/or fine particle pollution in other states. The EPA describes this rule as one that "protects the health of millions of Americans by helping states reduce

air pollution Air pollution is the presence of substances in the Atmosphere of Earth, air that are harmful to humans, other living beings or the environment. Pollutants can be Gas, gases like Ground-level ozone, ozone or nitrogen oxides or small particles li ...

and attain clean air standards."

Details

The CSAPR requires 23

United States state In the United States, a state is a constituent political entity, of which there are 50. Bound together in a political union, each state holds governmental jurisdiction over a separate and defined geographic territory where it shares its so ...

s to reduce their annual emissions of

sulfur dioxide Sulfur dioxide (IUPAC-recommended spelling) or sulphur dioxide (traditional Commonwealth English) is the chemical compound with the formula . It is a colorless gas with a pungent smell that is responsible for the odor of burnt matches. It is r ...

(SO₂) and

nitrogen oxides In atmospheric chemistry, is shorthand for nitric oxide () and nitrogen dioxide (), the nitrogen oxides that are most relevant for air pollution. These gases contribute to the formation of smog and acid rain, as well as affecting tr ...

(NO_x) to help downwind states attain the 24-hour

National Ambient Air Quality Standards The U.S. National Ambient Air Quality Standards (NAAQS, pronounced ) are limits on atmospheric concentration of six pollutants that cause smog, acid rain, and other health hazards. Established by the United States Environmental Protection Agency ...

, and 25 states to reduce ozone season nitrogen oxide emissions to help downwind states attain the 8-hour NAAQS. The states that are required to reduce sulfur dioxide emissions are divided into two groups, both of which must reduce their emissions in 2012. Group 1 is required to make additional emissions reductions by 2014.

History

Reception

The CSAPR has been defended by environmental groups such as the

Environmental Defense Fund Environmental Defense Fund or EDF (formerly known as Environmental Defense) is a United States–based nonprofit environmental advocacy group. The group is known for its work on issues including global warming, ecosystem restoration, oceans, an ...

, progressive think tanks such as

ThinkProgress ''ThinkProgress'' was an American Progressivism in the United States, progressive news website that was active from 2005 to 2019. It was a project of the Center for American Progress#Center for American Progress Action Fund, Center for America ...

, and publications such as the ''

Huffington Post ''HuffPost'' (''The Huffington Post'' until 2017, itself often abbreviated as ''HPo'') is an American progressive news website, with localized and international editions. The site offers news, satire, blogs, and original content, and covers ...

''.

References

{{reflist

External links

Official ruling
Air pollution in the United States United States federal environmental legislation