Section 37.03.09.030 - CONSTRUCTION OF LOW TEMPERATURE GEOTHERMAL RESOURCE WELLS AND BONDING01.General. Drillers constructing low temperature geothermal resource wells (bottom hole temperature more than eighty-five (85) degrees Fahrenheit and less than two hundred twelve (212) degrees Fahrenheit) must be qualified under the Well Driller Licensing Rules. All low temperature geothermal resource wells must be constructed in such a manner that the resource will be protected from waste due to lost artesian pressure and temperature. The owner or well driller is required to provide bottom hole temperature data, but the Director may make the final determination of bottom hole temperature, based upon information available to him.a. All standards and guidelines for construction and decommissioning (abandonment) of cold water wells apply to low temperature geothermal resource wells except as modified by Rule 30, Subsections 030.03, 030.04, and 030.06.b. A drilling prospectus must be submitted to and approved by the Director prior to the construction, modification, deepening or decommissioning (abandonment) of any low temperature geothermal resource well. The well owner and the well driller are responsible for the prospectus and subsequent well construction.02.Well Owner Bonding. The owner of any low temperature geothermal resource well must file a surety bond or cash bond as required by Section 42-233, Idaho Code, with the Director in an amount not less than five thousand dollars ($5,000) nor more than twenty thousand dollars ($20,000) payable to the Director prior to constructing, modifying or deepening the well after July 1, 1987. The bond amount will be determined by the Director within the following guidelines. The bond will be kept in force for one (1) year following completion of the well or until released in writing by the Director, whichever occurs first. a. Any well less than three-hundred (300) feet deep with a bottom hole temperature of less than one hundred twenty (120) degrees Fahrenheit and a shut-in pressure of less than ten (10) pounds per square inch gage (psig) at land surface must maintain a bond of five thousand dollars ($5,000).b. The owner of any well three hundred (300) feet to one thousand (1,000) feet deep with a bottom hole temperature of less than one hundred fifty (150) degrees Fahrenheit and a shut-in pressure of less than fifty (50) psig at land surface must maintain a bond of ten thousand dollars ($10,000).c. The owner of any low temperature geothermal resource well not covered by Rule 30, Subsections 030.02.a. and 030.02.b. must maintain a bond of twenty thousand dollars ($20,000).d. The Director may decrease or increase the bonds required if it is shown to his satisfaction that well construction or other conditions merit an increase or decrease.e. The bond requirements of Section 42-233, Idaho Code, are applicable to wells authorized by water right permits or licenses having a priority date earlier than July 1, 1987, if the well authorized by the permit or license was not constructed prior to July 1, 1987 or if an existing well constructed within the terms of the permit or license is modified, deepened or enlarged on or after July 1, 1987.03.Casing. Low temperature geothermal resource wells must be properly cased and sealed to protect from cooling by preventing intermingling with cold water aquifers. a. Steel casing which meets or exceeds the minimum specifications for permanent steel casing of Rule 25, Subsection 025.04 must be installed in every well. The Director may require a more rigid standard for collapse and burst strength as depths or pressures may dictate. Every low temperature geothermal resource well which flows at land surface must have a minimum of forty (40) feet of conductor pipe set and cemented its entire length.b. Casing must be installed from twelve (12) inches above land surface into the overlying confining strata of the thermal aquifer. The casing schedule may consist of several different casing strings (i.e. conductor pipe, surface casing, intermediate casing, production casing) which may all extend to land surface or may be overlapped and sealed or packed to prevent fluid migration out of the casing at any depth (Figure 13, Appendix A).i. Low temperature geothermal resource wells less than one thousand (1,000) feet deep and which encounter a shut-in pressure of less than fifty (50) psig at land surface must have two (2) strings of casing set and cemented to land surface. Conductor pipe must be a minimum of forty (40) feet in length or ten percent (10%) of the total depth of the well whichever is greater. Surface casing must extend into the confining stratum overlying the aquifer.ii. Low temperature geothermal resource wells one thousand (1,000) feet or more in depth or which will likely encounter a shut-in pressure of fifty (50) psig or more at land surface require prior approval of the drilling plan by the Director and must have three strings of casing cemented their total length to land surface. Conductor pipe must be a minimum length of forty (40) feet. Surface casing must be a minimum of two hundred (200) feet in length or ten percent (10%) of the total depth of the well, whichever is greater. Intermediate casing must extend into the confining stratum overlying the aquifer.c. Subsection 030.03.b. may be waived if it can be demonstrated to the Director through the lithology, electrical logs, geophysical logs, injectivity tests or other data that formations encountered below the last casing string set, will neither accept nor yield fluids at anticipated pressure to the borehole.d. A nominal borehole size of two (2) inches in diameter larger than the Outside Diameter (O.D.) of the casing or casing coupler (whichever is larger) must be drilled. All casing designations must be by O.D. and wall thickness and must be shown to meet a given specification of the American Petroleum Institute, the American Society for Testing and Materials, the American Water Works Association or the American National Standards Institute. The last string of casing set during drilling operations must, at the Director's option, be flanged and capable of mounting a valve or blow out prevention equipment to control flows at the surface before drilling resumes.04.Sealing of Casing. All casing must be sealed its entire length with cement or a cement grout mixture unless waived by the Director. The seal material must be placed from the bottom of the casing to land surface either through the casing or tubing or by use of a tremie pipe. The cement or cement grout must be undisturbed for a minimum of twenty-four (24) hours or as needed to allow adequate curing. a. A caliper log may be run for determining the volume of cement to be placed with an additional twenty-five (25%) percent on site ready for mixing. If a caliper log is not run, an additional one hundred (100%) percent of the calculated volume of cement must be on site ready for placement.b. If there is no return of cement or cement grout at the surface after circulating all of the cement mixture on site, the Director will determine whether remedial work should be done to insure no migration of fluids around the well bore.c. The use of additives such as bentonite, accelerators, retarders, and lost circulation material must follow manufacturer's specifications.05.Blow Out Prevention Equipment. The Director may require the installation of gate valves or annular blow out prevention equipment to prevent the uncontrolled blow out of drilling mud and geothermal fluid.06.Repair of Wells. The well driller must submit a drilling prospectus to the Director for review and approval prior to the repair or modification of a low temperature geothermal resource well.07.Decommissioning (Abandoning) of Wells. Proper decommissioning (abandonment) of any low temperature geothermal resource well requires the following:a. All cement plugs must be pumped into the hole through drill pipe or tubing.b. All open annuli must be completely filled with cement.c. A cement plug at least one hundred (100) feet in vertical depth must be placed straddling (fifty (50) feet above and fifty (50) feet below) the zone where the casing or well bore meets the upper boundary of each ground water aquifer.d. A minimum of one hundred (100) feet of cement must be placed straddling each drive shoe or guide shoe on all casing including the bottom of the conductor pipe.e. A surface plug of either cement grout or concrete must be placed from at least fifty (50) feet below the top of the casing to the top of the casing.f. A cement plug must extend at least fifty (50) feet above and fifty (50) feet below the top of any liner installed in the well. The Director may waive this rule upon a showing of good cause.g. Other decommissioning (abandonment) procedures may be approved by the Director if the owner or operator can demonstrate that the low temperature geothermal resource, ground waters, and other natural resources will be protected.h. Approval for decommissioning (abandonment) of any low temperature geothermal well must be in writing by the Director prior to the beginning of any decommissioning (abandonment) procedures.Idaho Admin. Code r. 37.03.09.030