All geothermal resources permit applications shall include details regarding the design, construction and operation of a system designed to temporarily store and dispose of drilling wastes and other process fluids during periods of well or facility maintenance. The division will approve two methods, pit or closed-loop system, for the handling of drilling fluids or other process fluids released during well or facility maintenance activities. The plan for design and construction of a pit shall follow the applicable liner manufacturer's requirements. The operating details shall include operating and maintenance procedures, a closure plan and hydrogeologic data that provides sufficient information and detail on the site's topography, soils, geology, surface hydrology and ground water hydrology to enable the division to evaluate compliance with acceptable siting criteria. In the absence of site-specific ground water data, the permittee may provide a reasonable determination of probable ground water depth using data generated by models, cathodic well lithology, published information or other tools as approved by the division.
A.Siting.(1) A permittee may locate a pit containing fluids containing 10,000 mg/l or less of TDS and 1 mg/l or less of H2S: (a) where ground water is more than four feet below the bottom of the pit;(b) 100 feet or more from any continuously flowing watercourse or any other significant watercourse;(c) 100 feet or more from any lakebed, sinkhole or playa lake (measured from the ordinary high-water mark);(d) 200 feet or more from an occupied permanent residence, school, hospital, institution or church in existence at the time of initial application;(e) 200 feet or more from a spring or a private, domestic fresh water well used by less than five households for domestic or stock watering purposes; or 200 feet or more from any other fresh water well or spring, in existence at the time of the initial application;(f) outside incorporated municipal boundaries or outside a defined municipal fresh water wellfield covered under a municipal ordinance adopted pursuant to Section 3-27-3 NMSA 1978, as amended, unless the municipality specifically approves;(g) 100 or more feet from a wetland;(h) outside the area overlying a subsurface mine, unless the division grants a variance that approves the proposed location based upon the permittee's demonstration that the pit's construction and use will not compromise the subsurface integrity;(i) outside an unstable area, unless the division grants a variance upon a demonstration that the permittee has incorporated engineering measures into the design to ensure that the pit's integrity is not compromised; and(j) outside a 100-year floodplain unless the division grants a variance for temporary use.(2) A permittee shall not locate a pit containing fluids containing more than 10,000 mg/l of TDS and more than one mg/l of H2S:(a) where ground water is less than 50 feet below the bottom of the pit;(b) within 300 feet of any continuously flowing watercourse or any other significant watercourse;(c) within 200 feet of any lakebed, sinkhole or playa lake (measured from the ordinary high-water mark);(d) within 300 feet from an occupied permanent residence, school, hospital, institution or church in existence at the time of initial application;(e) within: (i) 500 feet of a spring or a private, domestic fresh water well used by less than five households for domestic or stock watering purposes; or(ii) 1,000 feet of any other fresh water well or spring, in existence at the time of the initial application;(f) within incorporated municipal boundaries or within a defined municipal fresh water wellfield covered under a municipal ordinance adopted pursuant to Section 3-27-3 NMSA 1978, as amended, unless the municipality specifically approves;(g) within 300 feet of a wetland;(h) within the area overlying a subsurface mine, unless the division grants a variance that approves the proposed location based upon the permittee's demonstration that the pit's construction and use will not compromise the subsurface integrity;(i) within an unstable area, unless the division grants a variance upon a demonstration that the permittee has incorporated engineering measures into the design to ensure that the pit's integrity is not compromised; or(j) within a 100-year floodplain.B.Design and construction. A permittee shall design and construct a pit or closed-loop system to contain liquids and solids; prevent contamination of fresh water; and protect life, health, property, natural resources, the environment and the public welfare. (1) The pit or closed-loop system shall ensure the confinement of liquids to prevent releases.(2) A pit shall have a properly constructed foundation and interior slopes consisting of a firm, unyielding base, smooth and free of rocks, debris, sharp edges or irregularities to prevent the liner's rupture or tear. The permittee shall construct a pit so that the slopes are no steeper than two horizontal feet to one vertical foot (2H:1V).(3) The permittee shall design and construct a pit with a geomembrane liner. The geomembrane liner shall consist of 20-mil string reinforced LLDPE or equivalent liner material that the division approves. The geomembrane liner shall be composed of an impervious, synthetic material that is resistant to petroleum hydrocarbons, salts and acidic and alkaline solutions. The liner material shall be resistant to ultraviolet light. Liner compatibility shall comply with EPA SW-846 Method 9090A.(4) The permittee shall minimize liner seams and orient them up and down, not across, a slope. The permittee shall use factory welded seams where possible. Prior to field seaming, the permittee shall overlap liners four to six inches. The permittee shall minimize the number of field seams in corners and irregularly shaped areas. Qualified personnel shall field weld and test liner seams.(5) Construction shall avoid excessive stress-strain on the liner.(6) Geotextile is required under the liner where needed to reduce localized stress-strain or protuberances that may otherwise compromise the liner's integrity.(7) The permittee shall anchor the edges of all liners in the bottom of a compacted earth-filled trench. The anchor trench shall be at least 18 inches deep, unless anchoring to encountered bedrock provides equivalent anchoring.(8) The permittee shall ensure that the liner is protected from any fluid force or mechanical damage at any point of discharge into or suction from the lined pit.(9) The permittee shall design and construct a pit to prevent run-on of surface water. A berm, ditch, proper sloping or other diversion shall surround a pit to prevent run-on of surface water. During drilling operations, the edge of the pit adjacent to the drilling or workover rig is not required to have run-on protection if the permittee is using the pit to collect liquids escaping from the drilling or workover rig and run-on will not result in a breach of the pit.(10) The volume of a pit shall not exceed 10 acre feet, including freeboard.(11) Stockpiling of topsoil. Prior to constructing a pit, the permittee shall strip and stockpile the topsoil for use as the final cover or fill at the time of closure.(12) Signs. The permittee shall post an upright sign not less than 12 inches by 24 inches with lettering not less than two inches in height in a conspicuous place on the fence surrounding the pit. The permittee shall post the sign in a manner and location such that a person can easily read the legend. The sign shall provide the following information: the permittee's name; the location of the site by quarter-quarter or unit letter, section, township and range; and emergency telephone numbers.(13) A permittee who is using a closed-loop system with drying pads shall design and construct the drying pads to include the following: (a) appropriate liners that prevent the contamination of fresh water and protect life, health, property, natural resources, the environment and the public welfare;(b) sumps to facilitate the collection of liquids derived from drill cuttings; and(c) berms that prevent run-on of surface water or fluids.C.Fencing. The permittee shall fence or enclose a pit in a manner that deters unauthorized access and shall maintain the fences in good repair. Fences are not required if there is an adequate surrounding perimeter fence that prevents unauthorized access to the well site or facility, including the pit. During drilling or workover operations, the permittee is not required to fence the edge of the pit adjacent to the drilling or workover rig.D.Operation. A permittee shall maintain and operate a pit or closed-loop system in accordance with the following requirements. (1) The permittee shall operate and maintain a pit or closed-loop system, to contain liquids and solids and maintain the integrity of the liner, liner system or secondary containment system, prevent contamination of fresh water and protect life, health, property, natural resources, the environment and the public welfare.(2) The permittee may only discharge fluids or mineral solids generated or used during the well drilling, completion or workover or facility maintenance operations process into a pit or closed-loop system. The permittee shall maintain a pit free of miscellaneous solid waste or debris.(3) If the permittee elects to remove any stored fluids from a pit or a closed-loop system, the permittee shall dispose of the fluids pursuant to 19.11.4.20 NMAC.(4) The permittee shall maintain at least two feet of freeboard in a pit. For temporary extenuating circumstances, a permittee may maintain a freeboard of less than two feet and shall maintain a log describing such circumstances and make the log available to the division upon request.(5) The permittee shall inspect a pit or closed-loop system containing drilling fluids at least daily while the drilling or workover rig is on location. Thereafter, the permittee shall inspect the pit weekly so long as liquids remain in the pit. The permittee shall maintain a log of such inspections and make the log available for the division's review upon request.(6) The permittee shall not discharge into or store any hazardous waste in a pit or drying pad associated with a closed-loop system.(7) If a pit liner's integrity is compromised above the liquid's surface then the permittee shall repair the damage or initiate replacement of the liner within 48 hours of discovery.(8) If a pit or closed loop system develops a leak, or if any penetration of the pit liner occurs below the liquid's surface, then the permittee shall remove all liquid above the damage or leak within 48 hours of discovery, notify the division and repair the damage or replace the pit liner or closed loop hardware.(9) The permittee shall inject or withdraw liquids from a pit through a header, diverter or other hardware that prevents damage to the liner by erosion, fluid jets or impact from installation and removal of hoses or pipes.(10) The permittee shall operate and install a pit to prevent the collection of surface water run-on.(11) The permittee shall install, or maintain on site, a water absorbent boom or other device to contain an unanticipated release.E.Closure and remediation. A closure plan shall describe the proposed closure method and the proposed procedures and protocols to implement and complete the closure. (1) The permittee shall not commence closure without first obtaining division approval of the closure plan submitted with the permit application.(2) Prior to closure the permittee shall remove all free liquids reasonably achievable from the pit or drying pad and tank associated with a closed-loop system and dispose of such liquids at a division-approved facility.(3) When closing a pit, the permittee shall stabilize or solidify the remaining pit contents to a capacity sufficient to support the final cover of the pit. When transferring the geothermal waste contents from a drying pad and tank associated with a closed-loop system into a pit, the permittee shall stabilize or solidify the geothermal waste contents to a capacity sufficient to support the final cover of the pit. The permittee shall not mix the contents with soil or other material at a mixing ratio of greater than 3:1, soil or other material to contents. The geothermal waste mixture must pass the paint filter liquids test (EPA SW-846 Method 9095B or other test methods approved by the division).(4) The permittee shall collect, at a minimum, a five-point composite of the contents of the pit to demonstrate that, after the geothermal waste is solidified or stabilized with soil or other non-geothermal waste material at a ratio of no more than 3:1 soil or other non-geothermal waste material to geothermal waste, the concentration of any contaminant in the stabilized geothermal waste is not higher than the parameters listed in Table 2 (19.11.4.19 NMAC).(5) If, after appropriate stabilization, the concentrations of all contaminants in the contents from a pit are less than or equal to the parameters of listed in Table 2 (19.11.4.19 NMAC), the permittee may proceed with closure and remediation of the pit.(6) If the concentration of any contaminant in the contents, after mixing with soil or non-geothermal waste material to a maximum ratio of 3:1, from a pit or drying pad associated with a closed-loop system is higher than constituent concentrations shown in Table 2 (19.11.4.19 NMAC), then the permittee shall close the pit or drying pad by first removing all contents and, if applicable, synthetic liners and transferring those materials to a division-approved facility.(7) Upon achieving all applicable geothermal waste stabilization in the pit or transfer of stabilized geothermal wastes to the pit, the permittee shall: (a) fold the outer edges of the pit liner to overlap the geothermal waste material in the pit prior to installing the geomembrane cover;(b) install a geomembrane cover over the geothermal waste material in the pit; the permittee shall install the geomembrane cover in a manner that prevents the collection of infiltration water in the pit and on the geomembrane cover after the soil cover is in place; the geomembrane cover shall consist of a 20-mil string reinforced LLDPE liner or equivalent cover that the division approves; the geomembrane cover shall be composed of an impervious, synthetic material that is resistant to petroleum hydrocarbons, salts and acidic and alkaline solutions; cover compatibility shall comply with EPA SW-846 Method 9090A; and(c) cover the pit with non-geothermal waste containing uncontaminated, earthen materials and construct a soil cover prescribed by the division.(8) If the permittee has removed the geothermal wastes and the liner from a drying pad associated with a closed-loop system to a pit, the permittee shall test the soils beneath the drying pad as follows. (a) At a minimum, the permittee shall take a five-point composite sample to include any obvious stained or wet soils, or other evidence of contamination under the liner and have that sample analyzed for the constituents listed in Table 1 (19.11.4.18 NMAC).(b) If any contaminant concentration is higher than the parameters listed in Table 1 (19.11.4.18 NMAC) the division may require additional delineation upon review of the results and the permittee must receive division approval before proceeding with closure.(c) If all contaminant concentrations are less than or equal to the parameters listed in Table 1 (19.11.4.18 NMAC), the permittee can proceed to backfill the pad or excavation with non-geothermal waste containing, uncontaminated, earthen material.(9) A permittee shall notify the division at least 60 days prior to cessation of operations and provide a proposed schedule for closure. If there is no closure plan on file with the division applicable to the pit, the permittee shall provide a closure plan with this notice. Upon receipt of the notice and proposed schedule, the division shall review the current closure plan for adequacy and inspect the site. When onsite burial occurs on private land, the permittee shall file a deed notice identifying the exact location of the onsite burial with the county clerk in the county where the onsite burial occurs.(10) Within 60 days of closure completion, the permittee shall submit a closure report that documents all closure activities including sampling results; other information the division requires and details on back-filling, capping and covering, where applicable. In the closure report, the permittee shall certify that all information in the report and attachments is correct and that the permittee has complied with all applicable closure requirements and conditions specified in the approved closure plan. If the permittee elects to conduct onsite burial in an onsite pit, the permittee shall also provide a plat of the pit location. The permittee shall place a steel marker at the center of an onsite burial. The steel marker shall be not less than four inches in diameter and shall be cemented in a three-foot deep hole at a minimum. The steel marker shall extend at least four feet above mean ground level and at least three feet below ground level. The permittee name, lease name, well number and location, including unit letter, section, township and range, and that the marker designates an onsite burial location shall be welded, stamped or otherwise permanently engraved into the metal of the steel marker. A person shall not build permanent structures over an onsite burial without the division's written approval. A person shall not remove an onsite burial marker without the division's written permission.(11) A permittee shall close a drying pad associated with a closed-loop system or a pit within one year from the date that the permittee releases the drilling or workover rig. The permittee shall note the date of the drilling or workover rig's release, upon the well's or workover's completion. The division may grant an extension not to exceed one year.(12) Reclamation of pit and drying pad locations. (a) A permittee shall reclaim the pit or drying pad location and all areas associated with the closed-loop system or pit including associated access roads to a safe and stable condition that blends with the surrounding undisturbed area.(b) The permittee may propose an alternative to the re-vegetation or re-contouring requirement if the permittee demonstrates to the division that the proposed alternative provides equal or better prevention of erosion and protection from contamination of fresh water, and protection of life, health, property, natural resources, the environment and the public welfare.(c) The permittee shall compact, cover, pave or otherwise stabilize and maintain areas reasonably needed for production operations or for subsequent drilling operations in such a way as to minimize dust and erosion to the extent practicable.(d) The soil cover for closures after site contouring, where the permittee has removed the drying pad contents and liner, and if necessary remediated the soil beneath the drying pad liner to chloride concentrations less than 600 mg/kg as analyzed by EPA Method 300.0, shall consist of the background thickness of topsoil or one foot of suitable material, whichever is greater.(e) The soil cover for burial in-place pits shall consist of a minimum of four feet of non-geothermal waste containing uncontaminated, earthen material with chloride concentrations less than 600 mg/kg as analyzed by EPA Method 300.0. The soil cover shall include either the background thickness of topsoil or one foot of suitable material to establish vegetation at the site, whichever is greater.(f) The permittee shall construct the soil cover to the site's existing grade and prevent ponding of water and erosion of the cover material.(g) The permittee shall reclaim all areas disturbed by the closure of pits, except areas reasonably needed for production operations or for subsequent drilling operations, as early and as nearly as practicable to their original condition or their final land use and maintain them to control dust and minimize erosion to the extent practicable. The permittee shall replace top soils and subsoils to their original relative positions and contour them to achieve erosion control, long-term stability and preservation of surface water flow patterns. The permittee shall reseed disturbed area in the first favorable growing season following closure of a pit or drying pad associated with a closed-loop system. Reclamation of all disturbed areas no longer in use shall be considered complete when all ground surface disturbing activities at the site have been completed, and a uniform vegetative cover has been established that reflects a life-form ratio of plus or minus fifty percent of pre-disturbance levels and a total percent plant cover of at least seventy percent of pre-disturbance levels, excluding noxious weeds.(h) The permittee shall notify the division when reclamation and re-vegetation are complete.N.M. Admin. Code § 19.11.4.17
Adopted by New Mexico Register, Volume XXIX, Issue 04, February 27, 2018, eff. 2/27/2018