Attainment Area - doe-hdbk-1188-20060117

DOE-HDBK-1188-2006

14.

ATTAINMENT AREA. An area that the Environmental Protection Agency has designated as being

in compliance with one or more of the National Ambient Air Quality Standards (NAAQS) for sulfur

dioxide, nitrogen dioxide, carbon monoxide, ozone, lead, and particulate matter. An area may be in

attainment for some pollutants but not for others. (See National Ambient Air Quality Standards

(NAAQS), nonattainment area, and particulate matter.) [Derived from EPA Terms]

15.

AVERAGE (50%) METEOROLOGY. Meteorological conditions that, for a particular area,

correspond to the median amount of mixing of pollutants with the less contaminated surrounding air.

The term indicates conditions during which more favorable mixing conditions occur 50% of the time

and less favorable mixing conditions occur 50% of the time. The term "average meteorology" is often

used without further definition; it corresponds to a median value. [See conservative (95%)

meteorology.] [Derived from DOE 6430.1A]

16.

BACKGROUND RADIATION. Radiation from (1) cosmic sources, (2) naturally occurring

radioactive materials, including radon (except as a decay product of source or special nuclear

material), and (3) global fallout as it exists in the environment (e.g., from the testing of nuclear

explosive devices). [Derived from 10 CFR 20.1003, NRC Glossary]

17.

BASELINE. The existing environmental conditions against which impacts of the proposed action and

its alternatives can be compared.

For a specific NEPA document, a further statement can be included about the date or

conditions that are considered the baseline. For example: "For this Environmental Impact

Statement the environmental baseline is the environmental condition of the site as it exists in 1999."

18.

BEST AVAILABLE CONTROL TECHNOLOGY (BACT). Available devices, systems, or

techniques for achieving the maximum reduction of air-pollutant emissions while considering energy,

environmental, and economic impacts. BACT is determined on a case-by-case basis for new sources

or major modifications to existing sources in areas that are in attainment of National Ambient Air

Quality Standards (NAAQS). BACT does not permit emissions in excess of those allowed under any

Clean Air Act provisions. [See lowest achievable emissions rate (LAER), maximum achievable

control technology (MACT), reasonably achievable control technology (RACT), and National

Ambient Air Quality Standards (NAAQS).] [Derived from EPA Terms, 40 CFR 51.166(b)(12)]

19.

BEST AVAILABLE TECHNOLOGY (BAT). Under the Clean Water Act:

Economically achievable pollution control methods that will allow point sources to comply with the

effluent limitations required by the Clean Water Act. Factors to be taken into account in assessing

what is the best available technology include the age of equipment and facilities involved, the process

employed, the engineering aspects of the application of various types of control techniques, process

changes, the cost of achieving such effluent reduction, non-water quality environmental impact

(including energy requirements), and such other factors as the Environmental Protection Agency

Administrator deems appropriate. [Derived from CWA sects. 301(b) and 304(b)(2)(B)]

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