Washington Administrative Code › Title 344 - Oil and Gas Conservation Committee › Chapter 344-12 - General rules › DRILLING › Section 344-12-131 - Procedure for plugging

Current through Register Vol. 24-14, July 15, 2024
Each abandoned well drilled for the discovery of oil or gas or for any other purpose related to the exploration including seismic and core holes or production of oil and gas shall be plugged by or on behalf of the owner, operator, or producer who is in charge of the well or wells and responsible therefor. In general, cement plugs will be placed across specified intervals to protect oil and gas zones, to prevent degradation of potentially usable waters, and to protect surface conditions. Subject to approval of the supervisor, cement may be mixed with or replaced by other substances with adequate physical properties. The owner shall submit the proposed method and procedure for plugging to the supervisor on Form-3 (Notice of intention to abandon and plug well). Unless otherwise approved by the supervisor the method and procedure shall be as follows:
(1) Hole fluid. Drilling fluid having the proper weight and consistency to prevent movement of other fluids into the wellbore shall be placed in all intervals not plugged with cement, and shall be surface poured into all open annuli where required.
(2) Plugging by bailer. Placing of a cement plug by bailer shall not be permitted at a depth greater than 3,000 feet (914 meters). Water is the only permissible hole fluid in which a cement plug shall be placed by bailer.
(3) Surface pours. A surface cement-pour shall be permitted in an empty hole with a diameter of not less than 5 inches (12.7 centimeters). Depth limitations shall be determined on an individual well basis by the supervisor.
(4) Blowout prevention equipment. Blowout prevention equipment may be required during plugging and abandonment operations. Any blowout prevention equipment and inspection requirements deemed necessary by the supervisor shall appear on the approval issued by the supervisor.
(5) Junk in hole. Diligent effort shall be made to recover junk when such junk may prevent proper abandonment either in open hole or inside casing. In the event that junk cannot be removed from the hole and freshwater-saltwater contacts or oil or gas zones penetrated below cannot therefore be properly abandoned, cement shall be down-squeezed through or past the junk or a 100-foot (30-meter) cement plug shall be placed on top of the junk.
(6) A cement plug not less than 25 feet (7.6 meters) shall be placed in the hole and all annuli at the surface. All well casing shall be cut off at least 5 feet (1.5 meters) below the surface of the ground.
(7) Open hole.
(a) A cement plug shall be placed to extend from the total depth or at least 100 feet (30 meters) below the bottom of each oil or gas zone, whichever is less, to at least 100 feet (30 meters) above the top of each zone.
(b) A minimum 200-foot (61-meter) cement plug shall be placed across all underground source of drinking water-saltwater interfaces.
(c) An interface plug may be placed wholly within a thick shale if such shale separates the freshwater sands from the brackish or saltwater sands.
(d) The hole may be filled between plugs up to the base of the surface string, if this reaches below the freshwater zone, with approved heavy mud.