12 Va. Admin. Code § 5-630-450

Current through Register Vol. 41, No. 8, December 2, 2024

Section 12VAC5-630-450 - Well abandonment

A. The abandonment of a private well governed by this chapter or a private well abandoned as a condition of a permit issued under this chapter shall be administered by the Department of Health in conformance with this section. The owner or owner's agent shall provide advance notification regarding the initiation of well abandonment to the district or local health department to allow department personnel the opportunity to observe well abandonment. The owner or owner's agent shall be under no obligation to delay abandonment activities pending arrival of department personnel.

B. Prohibited materials. The following materials, even if classifiable as clean fill or beneficial use byproducts in other applications, shall not be used as clean fill or grout in any well abandonment procedure.

1. Contaminated media.

2. Non-manufactured gravel, brick, broken concrete, crushed glass, porcelain, or road pavement, except as these materials are present as incidental constituents of undisturbed soil or natural earth materials.

3. Controlled low strength material (flowable fill) or other product incorporating fly ash, other coal combustion byproduct, or other waste.

C. Temporary abandonment. A temporarily abandoned well shall be sealed with a water-tight cap or well head seal. Such a well shall be maintained so that it will not be a source or channel for contamination to groundwater during temporary abandonment.

D. Permanent abandonment. The object of proper permanent abandonment is to prevent contamination from reaching groundwater resources via a component of the well, including casing, annular space, and well cap. Permanently abandoned wells, with the exception of bored wells abandoned per the methods identified in subdivisions 5 a and 5 b (3) of this subsection shall no longer be classified as wells. A permanently abandoned well shall be abandoned in the following manner:

1. Casing material may be salvaged.

2. Before the well is abandoned, it shall be checked from land surface to the entire depth of the well to ascertain freedom from obstructions that may interfere with abandonment operations.

3. The well shall be thoroughly chlorinated using the dosage rates in 12VAC5-630-430 prior to abandonment.

4. Grout used in well abandonment shall conform to 12VAC5-630-400 E.

5. Bored wells, rock or brick-lined, and uncased wells shall be abandoned using one of the following methods:

a. Clean fill method. Bored, rock or brick-lined, and uncased wells abandoned by this method shall remain designated as wells with respect to the siting of onsite sewage treatment system components per the requirements of 12VAC5-610 and 12VAC5-613. The well shall be backfilled with clean fill to the water level. A two-foot-thick bentonite plug shall be placed immediately above the water level. Clean fill shall be placed on top of the bentonite plug and brought up to at least five feet from the ground surface. The top five feet of the well casing, if present, shall be removed from the bore hole. If an open annular space is present around the well casing, the annular space shall be filled with grout to the maximum depth possible, but not less than or equal to 20 feet. A one-foot-thick cement or bentonite grout plug that completely fills the bore void space shall be placed a minimum of five feet from the ground surface. The remaining space shall be filled with clean fill which is mounded a minimum of one foot above the surrounding ground surface. When the well is fewer than 25 feet deep, this procedure shall be followed to the greatest extent possible, including removing at a minimum the top five feet of casing below ground and grouting the open annular space as described in this subdivision. The location of these wells shall be permanently marked for future reference.

b. Grout abandonment method. Bored, rock or brick-lined, and uncased wells abandoned by this method shall no longer be designated as wells, with the exception of subdivision 5 b (3) of this subsection. At a minimum, the top five feet of well casing below ground, if present, shall be removed from the well bore.

(1) When a continuous annular space is present around the well casing, the annular space shall be filled with grout, placed via a tremie pipe, to the maximum depth possible, but not less than 20 feet.

(2) When an annular space is present but not continuous, materials shall be completely removed from the annular space to the maximum depth possible, but not less than 20 feet, and the annular space shall be filled with grout placed via a tremie pipe.

(3) When an annular space is present but not continuous, and cannot be cleared sufficiently for the annular space to be filled with grout to a depth not less than 20 feet, then accessible annular space will be filled with grout placed via a tremie pipe. Wells in which the annular space cannot be filled with grout to depth of at least 20 feet shall be treated as a well with respect to the siting of onsite sewage treatment components per the requirements of 12VAC5-610 and 12VAC5-613.

(4) If existing well documentation (uniform water well completion report) indicates that the annular space is filled with grout to a minimum depth of 20 feet, the condition of the grout shall be confirmed by visual observation of the top of the grout following the removal of the top five feet of well casing below ground. If the grout appears intact, no further confirmation of grout condition shall be required and abandonment shall proceed. If the grout condition appears compromised based on visual examination, then the requirements of subdivision 5 b (2) or 5 b (3) of this subsection shall apply.

(5) Once the annular space is addressed, the well shall be pumped dry and completely filled with grout poured from the surface. If the well is not pumped dry, grout shall be placed by introduction through a tremie pipe. The placement of grout in the well bore shall completely fill the bore void space to within a minimum of five feet from the ground surface. The well shall be capped with clean fill which is mounded a minimum of one foot above the surrounding ground surface. When the well is fewer than 25 feet deep, this procedure shall be followed to the greatest extent possible, including removing at a minimum the top five feet of casing below ground and cleaning or grouting the open annular space as described in this subdivision.

6. Drilled wells, including observation, monitoring, and remediation wells constructed in collapsing material shall be completely filled with grout placed via a tremie pipe. The well shall be capped with clean fill mounded to a minimum of one foot above the surrounding ground surface and graded to provide positive drainage away from the well.

7. Drilled wells, including observation, monitoring, and remediation wells, constructed in consolidated rock formations or which penetrate zones of consolidated rock shall be completely filled with grout placed via a tremie pipe. At the discretion of the water well service provider, the well may be filled with sand or gravel opposite the zones of consolidated rock. The top of the sand or gravel fill shall be at least five feet below the top of the consolidated rock and at least 20 feet below the land surface. The remainder of the well shall be filled with grout placed via a tremie pipe. The well shall be capped with clean fill mounded to a minimum of one foot above the surrounding ground surface and graded to provide positive drainage away from the well.

8. Other abandonment procedures may be approved by the division on a case by case basis.

9. When bored wells are advanced and a water source is not found, and the casing has not been placed in the bore hole, the well bore shall be abandoned by backfilling with the cuttings or clean fill or both to at least five feet below the ground surface. A two-feet-thick plug of grout shall be placed at a minimum of five feet from the ground surface. The remainder of the bore hole shall be filled with the cuttings or clean fill or both.

12 Va. Admin. Code § 5-630-450

Derived from VR355-34-100 §3.11, eff. April 1, 1992; Amended, Virginia Register Volume 41, Issue 04, eff. 11/6/2024.

Statutory Authority: §§ 32.1-12 and 32.1-176 of the Code of Virginia.