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Table 8
Clean Air Act (66)
National Ambient Air Quality Standards (NAAQS)
Criteria pollutants
PM, SO , CO, NO , O , Pb
2 x 3
New Source Performance Standards (NSPS)
Criteria pollutants
Designated pollutants (e.g., total reduced sulfur)
National Emission Standards for Hazardous Air Pollutants
(NESHAP)
Source: US EPA.

To address organic air emissions from tanks, surface impoundments, and containers,
coverage of the RCRAair standards would be expanded by Phase II standards. These stan-
dards are designed to contain (or suppress) potential organic emissions from escaping
prior treatment. As dictated by the standards, operators would be required, for example, to
cover open tanks containing organic waste unless it can be demonstrated that the concen-
tration of organic material in the waste is below a specific level. Because the control
requirements are initiated by the organic concentration of the waste in the container, these
standards are described as “waste-based” rules. According to the Phase II RCRA air
standards, waste treatment is not required; however, treatment is required under LDR. For
benzene waste, the national emissions standards for hazardous air pollutants (NESHAP)
require containment-type control prior to treatment. This requirement is similar to require-
ments under Phase II RCRA air standards. Additionally, NESHAP requires waste
containing benzene to meet treatment requirements.
Table 8 lists the major regulatory programs established under the CAA. These pro-
grams address organic air emissions, ozone precursors, and air toxics. The US EPA, as
discussed previously, establishes the NAAQS for “criteria” pollutants. States are then
required to set standards to attain and maintain NAAQS. Because ozone is a criteria
pollutant, states regulate VOCs (ozone precursors) on a source-by-source basis.
Additionally, Section 111 of CAA sets new source performance standards (NSPS) for
emissions of criteria pollutants. These sources include new, modified, or reconstructed
stationary sources. Other pollutants may also be addressed by NSPS. These pollutants
are classified as “designated pollutants.” Designated pollutants are noncriteria pollu-
tants that are identified by the US EPA for regulation under CAA Section 111(d) based
on impact on health and welfare. Total reduced sulfur (TRS) and sulfuric acid mist are
examples of designated pollutants (66).
Section 112 of the CAA establishes the NESHAP standards, which identify and limit
hazardous pollutant emissions from both existing and new stationary sources. The 1990
CAA amendments substantially change Section 112. Prior to 1990, Section 112 required
the US EPA to first list the pollutant as hazardous and then to establish standards to pro-
tect public health “with an ample margin of safety.” The amended Section 112 requires
the US EPA to establish technology-based standards for the sources of 190 hazardous
pollutants listed in the new law. Additionally, the law requires further action by US EPA