R307.  Environmental Quality, Air Quality.
R307-510.  Oil and Gas Industry:  Natural Gas Engine Requirements.
R307-510-1.  Purpose.
	R307-510 establishes control requirements for stationary engines associated with well sites.

R307-510-2.  Definitions.
	"Site hp" means the total horse power rating of all engines within the boundaries of the source.

R307-510-3.  Applicability.
	(1)  R307-510 applies to each natural gas-fired engine at a well site as defined in 40 CFR 60.5430a, Subpart OOOOa Standards of Performance for Crude Oil and Natural Gas Production, Transmission and Distribution, that began operations, installed new engines, or made modifications to existing engines after January 1, 2016.
	(2)  R307-510 shall apply to centralized tank batteries, as defined in R307-506-2.
	(3)  R307-510 does not apply to a natural gas-fired engine that is subject to an approval order issued under R307-401-8.

R307-510-4.  Engine Requirements.
	(1)  Regardless of construction, reconstruction, or modification date, each stationary engine at a well site shall comply with the emission standards listed in Table 1 when the engine is installed, relocated, or modified.

	Table 1

Maximum Engine hp             Emission Standards in (g/hp-hr)

                              NOx      CO    VOC    HC+NOx
Equal or greater than          -      4.85    -      2.83
25 hp and < 100 hp
Equal or greater than         1.0     2.0    0.7      -
100 hp
	
	(2)  The owner or operator shall either:
	(a)  purchase a certified stationary internal combustion engine as defined in 40 CFR 60.4248, or
	(b)  conduct an initial performance test according to 40 CFR 60.4244.
	(3)  Each engine shall vent exhaust gases vertically unrestricted with the following stack height requirements:
	(a)  For site hp ratings of 306 or greater, each engine shall have an attached stack height of no less than 10 feet.
	(b)  For site hp ratings of 151 to 305 hp, each engine shall have an attached stack height of no less than 8 feet.
	(c)  For site hp ratings of 150 hp or less, there are no stack height requirements on engines.

R307-510-5.  Recordkeeping.
	For each engine on site, the owner or operator shall maintain records of the engine certification or initial performance test for the period of time the engine is on the well site.

KEY:  air pollution, oil, gas
Date of Enactment or Last Substantive Amendment:  March 5, 2018
Authorizing, and Implemented or Interpreted Law:  19-2-104(1)(a)