4 Va. Admin. Code § 25-170-50

Current through Register Vol. 41, No. 6, November 4, 2024

Section 4VAC25-170-50 - Well construction and maintenance

A. Every person drilling for geothermal resources in Virginia, or operating, owning, controlling or in possession of any well as defined herein, shall post and keep posted in a conspicuous place on or near the well a sign showing the name of the person, firm, company, corporation, or association drilling, owning, or controlling the well, the company or operator's well number, and the well identification number thereof. Well identification numbers will be assigned to all approved permits according to the USGS groundwater site inventory system. The lettering on such sign shall be kept in a legible condition at all times.

B. The division director shall receive notice prior to the commencement of well work concerning the identification number of the well and the date and time that well work is scheduled to begin.

1. Drilling-fluid materials sufficient to ensure well control shall be maintained in the field area and be readily accessible for use during drilling operations.

2. All drilling muds shall be used in a fashion designed to protect freshwater-bearing sands, horizons, and aquifers from contamination during well construction.

3. Drilling muds shall be removed from the drilling site after the well is completed and disposed of in the method approved in the operations plan.

4. Operations shall be conducted with due care to minimizing the loss of reservoir permeability.

D. All wells must be drilled with due diligence to maintain a reasonably vertical well bore. Deviation surveys must be recorded in the drilling log for every 1000 feet drilled.

1. A well may deviate intentionally from the vertical with written permission by the division director. Such permission shall not be granted without notice to adjoining landowners, except for side-tracking mechanical difficulties.

2. When a well has been intentionally deviated from the vertical, a directional survey of the well bore must be filed with the department within 30 days after completion of the well.

3. The department shall have the right to make, or to require the operator to make, a directional survey of any well at the request of an adjoining operator or landowner prior to the completion of the well and at the expense of said adjoining operator or landowner. In addition, if the department has reason to believe that the well has deviated beyond the boundaries of the property on which the well is located, the department also shall have the right to make, or to require the operator to make, a directional survey of the well at the expense of the operator.

1. Valves approved by the division director shall be installed and maintained on every completed well so that pressure measurements may be obtained at any time.

2. Blow-out preventers during drilling shall be required when the formation pressure on the wellhead connection is or could be greater than 1000 psi.

1. Geothermal production wells shall be designed to ensure the efficient production and elimination of waste or escape of the resource.

2. All freshwater-bearing sands, horizons, and aquifers shall be fully protected from contamination during the production of geothermal fluids.

a. The water protection string shall extend from a point 12 inches above the surface to a point at least 50 feet below the deepest known groundwater aquifer or horizon.

b. The operator, owner, or designated agent shall use new casing. Only casing that meets American Petroleum Institute specifications, as found in API 5AC, Restricted Yield Strength Casing and Tubing, March, 1982, API 5A, Casing Tubing, and Drill Pipe, March, 1982, and API 5AX, High-Strength Casing, Tubing, and Drill Pipe, March, 1982, (and all subsequent revisions thereto), shall be used in geothermal production wells.

c. Cement introduced into a well for the purpose of cementing the casing or for the purpose of creating a permanent bridge during plugging operations shall be placed in the well by means of a method approved by the division director. In addition:

(1) Each surface string shall be cemented upward from the bottom of the casing to the surface.

(2) Cement shall be allowed to stand for 24 hours or until comprehensive strength equals 500 psi before drilling.

d. The department may modify casing and cementing requirements when special conditions demand it.

a. The owner, operator, or designated agent shall use new casing. Only production casing that meets American Petroleum Institute specifications, as found in API 5AC, Restricted Yield Strength Casing and Tubing, March, 1982, API 5A, Casing Tubing, and Drill Pipe, March, 1982, and API 5AX, High-Strength Casing, Tubing, and Drill Pipe, March, 1982, (and all subsequent revisions thereto), shall be used in geothermal production wells.

b. Each well shall be cemented with a quantity of cement sufficient to fill the annular space from the production zone to the surface. The production casing shall be cemented to exclude, isolate, or segregate overlapping and to prevent the movement of fluids into freshwater zones.

c. Cement shall be allowed to stand for 24 hours or until compressive strength equals 500 psi before drilling.

d. Cement introduced into a well for the purpose of cementing the casing or for the purpose of creating a permanent bridge during plugging operations shall be placed in the well by means of a method approved by the division director.

e. The department may modify casing requirements when special conditions demand it.

f. The division director may require additional well tests if production or monitoring records indicate a leak in the production casing. When tests confirm the presence of a production casing leak, the division director may require whatever actions are necessary to protect other strings and freshwater horizons.

1. The owner, operator, or designated agent shall use new casing. Only casing that meets American Petroleum Institute specifications, as found in API 5AC, Restricted Yield Strength Casing and Tubing, March, 1982, API 5A, Casing Tubing, and Drill Pipe, March, 1982, and API 5AX, High-Strength Casing, Tubing, and Drill Pipe, March, 1982, (and all subsequent revisions thereto), shall be used in geothermal injection wells.

2. The casing program shall be designed so that no contamination will be caused to freshwater strata. Injection shall be done through production casing adequately sealed and cemented to allow for monitoring of the annulus between the injection string and the last intermediate string or water protection string, as the case may be. Injection pressure shall be monitored and regulated to minimize the possibility of fracturing the confining strata.

3. Production casing shall be cemented through the entire freshwater zone.

4. The rate of injection of geothermal fluid shall not exceed the production rate.

5. Adequate and proper wellhead equipment shall be installed and maintained in good working order on every injection well not abandoned and plugged, so that pressure measurements may be obtained at any time.

1. The division director shall have access to geothermal well sites during reasonable hours.

2. The state geologist or his designated representative shall have access to any drilling site for the purpose of examining whole cores or cuttings as may be appropriate.

J. At least 10 days prior to any chemical cleaning of production casing, the operator shall notify the division director of the type and amount of chemical to be used and obtain approval for its use.

K. The well operator, or his designated agent, shall file a completion report within 90 days after well work is completed. The completion report shall be accompanied by copies of any drilling logs required under 4VAC25-170-40.

4 Va. Admin. Code § 25-170-50

Derived from VR480-04-13 §5, eff. May 1, 1984; amended, Virginia Register Volume 29, Issue 2, eff. October 24, 2012; Amended, Virginia Register Volume 33, Issue 21, eff. 7/27/2017.

Statutory Authority: § 45.1-179.7 of the Code of Virginia.