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General Conformity

General Conformity Training Module 2.2: Emissions and Review

2.2.1 Estimation of the emissions caused by the action

Direct emissions are caused by the action itself, such as the emissions from the construction of a facility on government property. Indirect emissions are also caused by the action but are removed from the action in either time or space. For example, emissions from employees commuting to a government facility are indirect emissions. Both direct and indirect emissions have to be reasonably foreseeable, meaning that the emissions can be estimated based on acceptable techniques using reasonable assumptions about the type and quantity of equipment used.

For indirect emissions, the emissions must be of the type that "the agency can practically control" and for which "the agency has continuing program responsibility." A continuing program responsibility means that the agency has an oversight role over the activities generating the emissions or has the ability to limit the emissions. For example, an agency would have the ability to limit the emissions by specifying requirements in a contract or by conditioning a permit.

The “total direct and indirect emissions” is defined as the net emissions increase caused by the action considering all the emission increases and decreases that are projected to occur. For example, if a federal agency takes an action to replace an operation at a facility with a different type of operation, the total direct and indirect emissions would be the difference between the emissions from the two operations. The portion of emissions which are exempt or presumed to conform are not included in the “total of direct and indirect emissions.”

The de minimis emission levels are based upon the total annual emissions. Therefore, the total direct and indirect emissions include all of the annual emissions, even if some of the emissions occur outside of the season associated with the pollutant. Seasonal emissions can be considered the amount of emissions that need to be mitigated or offset when demonstrating conformity. The annual emissions from the total action are used to determine if they exceed the de minimis levels. The action cannot be segmented to create several smaller projects with the emissions from each compared to the de minimis levels. If an action involves more than one of the activities that are listed as presumed to conform, EPA regulations allow federal agencies to exempt a combination of presumed to conform actions that does not equal or exceed de minimis levels. The emissions from the other activities would be added into the total of the direct and indirect emissions for the de minimis level evaluation.

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2.2.2 Requirements for re-evaluation

General conformity evaluation is designed to be a one-time occurrence. The agency taking the action determines if the emissions are below the de minimis levels or if the action is otherwise exempt. If not, the agency demonstrates that the action conforms to the SIP/TIP. If the agency takes the action in a timely manner and does not modify the action so that emissions are increased, then the agency does not have to re-evaluate the conformity for the action. However, if the agency does not start a continuing program to implement the action within five years or if the action is modified resulting in an increase in emissions, a re-evaluation is required.

The General Conformity Regulations include a 5-year limit on the time to start the action to ensure that the conditions used to demonstrate conformity have not changed. If the agency does not start the action within five years, it is possible that the status of the nonattainment or maintenance area could have changed, or that the emission offset or mitigation measures may have been included in the SIP/TIP. A revised SIP/TIP is required to be submitted to EPA within 18 months. If the state or tribe is in the process of developing a new SIP/TIP and makes a written commitment to include the emissions in the new SIP/TIP and the SIP/TIP will be submitted within 18 months, then the federal agency can rely upon the state or tribe commitment for the demonstration.

2.2.3 Special Situations

Prescribed fires under EPA regulations are presumed to conform provided they are identified and conducted in accordance with a smoke management plan. These plans must meet the requirements of EPA's Air Quality Policy on wildfires and prescribed fires.

Generally water and waste water projects funded by the EPA do not require a conformity evaluation if the project is not increasing the capacity of the facility or if the projected growth served by the project is consistent with the growth estimates in the SIP/TIP.

In the General Conformity Regulations, EPA provides an exemption for the process of rulemaking. However, that exemption does not apply to the rule itself. Therefore, if the substance of the rule would cause an increase in emissions in nonattainment or maintenance areas, then the rule needs to be evaluated for conformity.

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2.2.4 Review of de minimis applicability determination

The General Conformity Regulations do not require any official review or reporting of a determination that the total direct and indirect emission are below the de minimis levels or are otherwise exempt. However, because the information is often discussed in the NEPA documents, environmental agencies and the public can learn about the analysis.

Although not required by the General Conformity Regulations, many federal agencies have found it helpful to include in their file a “record of decision” (ROD) or “record of non-applicability” (RONA) documenting the analysis that the action was below the de minimis level or was otherwise exempt. Such documentation is most helpful when the annual emissions are close to the de minimis level or for controversial actions that may be challenged. Since many of the actions are subject to the National Environmental Policy Act (NEPA) and must conduct either an Environmental Analysis or an Environmental Impact Statement, this documentation is often included in those activities.