Section 312IAC16-5-2. Drilling units

   (a) This section establishes drilling units.

  (b) For sandstone reservoirs, every quarter, quarter, quarter section containing ten (10) acres, more or less, as established by the official U.S. Public Lands Survey by the rectangular surveying system for the state.

  (c) For all other reservoirs, except in established Trenton limestone reservoirs, half a quarter, quarter section containing twenty (20) acres, more or less, as established by the official U.S. Public Lands Survey by the rectangular surveying system for the state. The use of any portion of one (1) quarter, quarter section with any portion of another quarter, quarter section is prohibited unless approved following an informal hearing conducted under 312 IAC 16-2-3.

  (d) For established Trenton limestone reservoirs, half of every quarter, quarter, quarter section containing five (5) acres, more or less, as established by the official U.S. Public Lands Survey by the rectangular surveying system for the state.

  (e) An exception to drilling unit requirements may be authorized following an informal hearing under 312 IAC 16-2-3, if the exception is supported by unusual regional or geological characteristics and is conducive to the most efficient and economical recovery of oil and gas.

  (f) A drilling unit may be established following an informal hearing under 312 IAC 16-2-3 for those areas not covered by the rectangular surveying system of the U.S. Public Lands Survey. The drilling unit shall conform as nearly as practicable to the drilling unit requirements for reservoirs of similar lithology in those areas covered by the rectangular surveying system.

  (g) For irregular sections containing more or less than six hundred forty (640) acres, the department may establish drilling units other than those defined in subsections (b) through (c) of approximately twenty (20) acres or ten (10) acres. (Natural Resources Commission; 312 IAC 16-5-2; filed Feb 23, 1998, 11:30 a.m.: 21 IR 2338; readopted filed Nov 17, 2004, 11:00 a.m.: 28 IR 1315; readopted filed Mar 25, 2010, 2:57 p.m.: 20100421-IR-312100033RFA; readopted filed Sep 30, 2015, 12:13 p.m.: 20151028-IR-312150224RFA)