40 CFR § 355.31 - What types of releases are exempt from the emergency release notification requirements of this subpart?
(e) Any radionuclide release that occurs:
(1) Naturally in soil from land holdings such as parks, golf courses, or other large tracts of land.
(2) Naturally from land disturbance activities, including farming, construction, and land disturbance incidental to extraction during mining activities, except that which occurs at uranium, phosphate, tin, zircon, hafnium, vanadium, monazite, and rare earth mines. Land disturbance incidental to extraction includes: Land clearing; overburden removal and stockpiling; excavating, handling, transporting, and storing ores and other raw (not beneficiated or processed) materials; and replacing in mined-out areas coal ash, earthen materials from farming or construction, or overburden or other raw materials generated from the exempted mining activities.
(f) Any release less than 1,000 pounds per 24 hours of nitrogen oxide or nitrogen dioxide to the air which is the result of combustion and combustion related activities.