§ 49.137 Rule for air pollution episodes.

(a) What is the purpose of this section? This section establishes procedures for addressing the excessive buildup of certain air pollutants during periods of stagnant air. This section is intended to prevent the occurrence of an air pollution emergency within the Indian reservation due to the effects of these air pollutants on human health.

(b) Who is affected by this section? This section applies to the Regional Administrator and any person who owns or operates an air pollution source within the Indian reservation.

(c) What are the requirements of this section?—(1) Air pollution action level triggers. Conditions justifying the declaration of an air pollution alert, air pollution warning, or air pollution emergency exist whenever the Regional Administrator determines that the accumulation of air pollutants in any place is approaching, or has reached, levels that could lead to a threat to human health. The following criteria will be used for making these determinations:

(i) Air stagnation advisory. An air stagnation advisory may be issued by the Regional Administrator whenever meteorological conditions over a large area are conducive to the buildup of air pollutants.

(ii) Air pollution alert. An air pollution alert may be declared by the Regional Administrator when any one of the following levels is reached, or is projected to be reached, at any monitoring site and the meteorological conditions are such that the level is expected to continue or reoccur over the next 24 hours.