Code of Federal Regulations Title 40. Protection of Environment § 40.257.3–8 Safety

(1) Twenty-five percent (25%) of the lower explosive limit for the gases in facility structures (excluding gas control or recovery system components);  and

(2) The lower explosive limit for the gases at the property boundary.

(1) Airport means public-use airport open to the public without prior permission and without restrictions within the physical capacities of available facilities.

(2) Bird hazard means an increase in the likelihood of bird/aircraft collisions that may cause damage to the aircraft or injury to its occupants.

(3) Explosive gas means methane (CH ₄).

(4) Facility structures means any buildings and sheds or utility or drainage lines on the facility.

(5) Lower explosive limit means the lowest percent by volume of a mixture of explosive gases which will propagate a flame in air at 25°C and atmospheric pressure.

(6) Periodic application of cover material means the application and compaction of soil or other suitable material over disposed solid waste at the end of each operating day or at such frequencies and in such a manner as to reduce the risk of fire and to impede disease vectors' access to the waste.

(7) Putrescible wastes means solid waste which contains organic matter capable of being decomposed by microorganisms and of such a character and proportion as to be capable of attracting or providing food for birds.