NAC522.445. Method of plugging.

     1. Each abandoned well or hole must be plugged by or on behalf of the owner, operator or producer who is in charge of the well and responsible for it.

     2. Before any well is abandoned, it must be plugged in a manner which will permanently confine all oil, gas and water to the separate strata which originally contained them. Unless a different method and procedure is approved by the division, upon application by the owner, operator or producer on Form 4, the method and procedure for plugging the well is as follows:

     (a) The hole must be filled with mud-laden fluid and a permanent type of bridge plug must be placed at the top of each hydrocarbon-producing formation open to the wellbore, or a cement plug not less than 100 feet in length must be placed immediately above each hydrocarbon-producing formation open to the wellbore.

     (b) A cement plug not less than 100 feet in length must be placed at approximately 50 feet below and 50 feet above the interface between brackish and fresh water.

     (c) A 50-foot concrete plug must be placed at or near the surface of the ground in each hole.

     (d) The interval between plugs must be filled with heavy mud-laden fluid which will effectively seal the formation to which it is applied.

     (e) An uncased hole must be plugged with heavy mud up to the base of the surface string and a cement plug not less than 100 feet in length must be placed and centered as nearly as practicable at the base of the surface casing.

     3. Before any hole drilled for seismic, core or other exploratory purpose is abandoned, the owner or driller must plug it so as to protect properly all water-bearing formations. The method and procedure for plugging an exploratory hole is as follows:

     (a) The hole must be filled to the top with the original cuttings or gravel.

     (b) If artesian flow is encountered, the hole must be filled with the original cuttings or gravel to 50 feet below the surface and plugged from 50 feet to the surface with concrete, to prevent the waste of water.

     [Div. of Mineral Res., §§ 301 & 303, eff. 12-20-79]—(NAC A by Dep’t of Minerals, 7-22-87)