(a) The operator of a Class I hazardous waste well shall prepare, maintain, and comply with a plan for closure of the well and post-closure care of the well that meets the standards for well closure required in paragraph (d) of this section and post-closure care required in paragraph (e) of this section and is acceptable to the administrator. The obligation to implement the closure and post-closure plan survives the termination of a permit or the cessation of injection activities. The requirement to maintain and implement an approved plan is directly enforceable regardless of whether the requirement is a condition of the permit. - (i) The operator shall submit the plan as part of the permit application, and, upon approval by the administrator, the plan shall be incorporated as a condition of any permit issued.
- (ii) The operator shall submit any proposed significant revision to the method of closure reflected in the plan for approval by the administrator no later than the date on which notice of closure is required under paragraph (b) of this section.
- (iii) The plan shall ensure financial responsibility as required in Section 19 of this chapter.
- (iv) The closure plan shall include the following information:
- (A) The type and number of plugs to be used.
- (B) The placement of each plug including the elevation of the top and bottom of each plug.
- (C) The type, grade, and quantity of material to be used in plugging.
- (D) The method of placement of the plugs.
- (E) Any proposed test or measure to be made.
- (F) The amount, size, and location (by depth) of casing and any other materials to be left in the well;
- (G) The method and location where casing is to be parted, if applicable.
- (H) The procedure to be used to meet the requirements of paragraph (d)(5) of this section;
- (I) The estimated cost of closure.
- (J) Any proposed test or measure to be made.
- (v) Post-closure plans shall include the following information:
- (A) The pressure in the injection zone before injection began.
- (B) The anticipated pressure in the injection zone at the time of closure.
- (C) The predicted time until pressure in the injection zone decays to the point that the well's cone of influence no longer intersects the base of the lowermost Underground Source Drinking Water.
- (D) Predicted position of the waste front at closure.
- (E) The status of any required cleanups; and
- (F) The estimated cost of proposed post-closure care.
- (vi) The administrator may modify a closure plan in accordance with the procedures outlined in Section 7 of this chapter governing modification of permits.
- (vii) An operator of a Class I hazardous waste injection well who ceases injection temporarily, may keep the well open provided:
- (A) The operator receives authorization from the administrator.
- (B) The operator has described actions or procedures, satisfactory to the administrator, that the operator will take to ensure that the well will not endanger Underground Source of Drinking Waters during the period of temporary disuse. These actions and procedures shall include compliance with the technical requirements applicable to active injection wells unless waived by the administrator.
- (viii) The operator of a well that has ceased operations for more than two years shall notify the administrator at least thirty (30) days prior to resuming operation of the well.
(b) The operator shall notify the administrator at least sixty (60) days prior to closure of a well. The administrator may allow a closure period of less than sixty (60) days.
(c) Within sixty (60) days after closure or at the time of the next quarterly report, whichever is less, except if the next quarterly report is due within fifteen (15) days, in which case the sixty (60) day requirement will be used, the operator shall submit a closure report to the administrator. - (i) Such report shall contain a certification by the operator and the person who performed the closure, if different from the operator, of the accuracy of the report, and:
- (A) A statement that the well was closed in accordance with the closure plan previously submitted and approved by the administrator.
- (B) Where actual closure differed from the plan previously submitted, a written statement specifying the differences between the previous plan and the actual closure.
(d) Standards for well closure. - (i) Prior to well closure, the owner or operator shall observe and record the pressure decay for a time specified by the administrator, who shall then analyze the pressure decay and the transient pressure observations conducted to determine whether the injection activity has conformed with predicted values.
- (ii) Prior to well closure, appropriate mechanical integrity testing shall be conducted to ensure the integrity of that portion of the long string casing and cement that will be left in the ground after closure. Testing methods shall be similar to the mechanical integrity tests required during the operating life of the well.
- (iii) Prior to well closure, the well shall be flushed with a buffer fluid.
- (iv) Upon closure, a Class I hazardous waste well shall be plugged with cement in a manner that will not allow the movement of fluids into or between any underground source of drinking water.
- (v) Placement of the cement plugs shall be accomplished by circulating cement to the bottom of the well using a working string. The working string shall be removed as the cement is pumped. The cement used shall be of a variety such that the working string can be withdrawn while still allowing the well to be filled with cement.
- (vi) Each plug used shall be appropriately tagged and tested for seal and stability before closure is completed.
- (vii) The well to be closed shall be in a state of static equilibrium with the mud weight equalized top to bottom, either by circulating the mud in the well at least once or by a comparable method described by the administrator, prior to the placement of the cement plugs.
(e) Post-closure care. - (i) The operator shall continue and complete any required cleanup action.
- (ii) The operator shall continue to conduct any groundwater monitoring required under the permit until pressure in the injection zone decays to the point that the well's cone of influence no longer intersects the base of the lowermost Underground Source of Drinking Water. The administrator may extend the period of post-closure monitoring if he or she determines that the well may endanger an Underground Source of Drinking Water.
- (iii) The operator shall submit a survey plat to the local zoning authority designated by the administrator, indicating the location of the well relative to permanently surveyed benchmarks. A copy of the plat shall be submitted to the Regional administrator of the U.S. EPA Region 8, the Wyoming State Engineer's Office, and to the Wyoming Oil and Gas Conservation Commission.
- (iv) The operator shall retain for a minimum of three (3) years following well closure, records reflecting the nature, composition and volume of all injected fluids. The administrator shall require the operator to deliver the records to the administrator at the conclusion of this retention period.
(f) Each owner of a Class I hazardous waste well, and the owner of the surface or subsurface property on or in which a Class I hazardous waste well is located, must record a notation on the deed to the facility property or on some other instrument which is normally examined during title search that will in perpetuity provide any potential purchaser of the property the following information: - (i) The fact that the land in question has been used to manage hazardous waste.
- (ii) The name of the State agency or local authority with which the plat was filed, as well as the address of the Environmental Protection Agency Region 8 to which it was submitted.
- (iii) The type and volume of waste injected, the injection interval or intervals into which it was injected, and the period over which injection occurred.
020-27 Wyo. Code R. § 27-17