Chapter 19.24 — STANDARDS

The standards prescribed shall be for each particular project and will pertain to that project only. Future projects may receive additional and/or different standards. (Ord. 239 § 6.10, 1973)

The following planning standards shall be used in developing any observation wells, exploratory geothermal wells, test facilities, or geothermal production projects:

• A. All geothermal drilling sites including test facilities and ponds shall be as small as possible and in no case larger than three acres on arable land. Exceptions will be allowed if two or more wells are drilled from the same site;

• B. Every site shall be designed to retain the maximum amount of usable agricultural land and the site shall not interfere with the irrigation and drainage pattern. Drill sites shall be constructed adjacent to existing roads insofar as possible. Well density shall be justified and in accordance with good reservoir engineering practices;

• C. Unless specifically waived by the planning commission where legally permissible, the following minimum distances shall be observed in siting a well:

• D. Production facilities shall, where possible, be located in centralized areas to serve the maximum number of wells. These shall include but are not limited to power plants, extraction plants, and separators;

• E. All electrical transmission lines shall be constructed on existing right-of-way wherever possible;

• F. The plans for all permanent sumps, brine ponds, waste holding ponds, and any other ponds, shall include a soils investigation report (which shall be filed with the county) and shall be designed and constructed under the supervision of a registered civil engineer. The following are considered minimum criteria:

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Inyo County, CA

GEOTHERMAL RESOURCE DEVELOPMENT

§ 19.24.020

§ 19.24.030

1. Pond bottoms and dikes shall be either impervious or shall be lined to prevent seepage,

2. Earthen dikes shall have 3:1 slopes and the outside shall be planted,

3. Dikes shall be designed to provide three feet freeboard when at design capacity,

4. The plan shall minimize wave and wind erosion,

5. Ponds and sumps shall be protected from any flood hazard.

The plans shall be submitted to the county for approval prior to beginning construction;

• G. A reproducible copy of the plot plan shall be submitted on suitable material. It shall be eighteen inches by twenty-six inches with an appropriate scale and shall be prepared in accordance with good engineering and drafting techniques. It shall show all existing topography and facilities and shall clearly show proposed development;

• H. Fire clearance of brush shall be as required by the appropriate state agency;

• I. The removal of ground cover in areas not immediately needed for normal operations shall be done only with the approval of the planning commission;

• J. Pollutants exhausted to the air, including dust and noxious gases, shall not exceed the standards set out in the county air pollution control rules and regulations and the ambient air quality standards established by the appropriate state agency.

• (Ord. 239 § 6.20, 1973)

The following drilling standards shall be used in developing any exploratory geothermal well or geothermal production project:

• A. All geothermal well sites shall have a sign having a surface of not less than two square feet and not more than six square feet bearing the current name and number of the well, the emergency telephone number of the agent, the name and/or insignia of the operator and the owner, and this sign shall be displayed at all times from the commencement of drilling operations until the well has been abandoned;

• B. The planning commission shall direct which noise level curve as shown on the chart shall apply. Each operator shall limit the continuous generation of wide band noise to that required. The level may be exceeded by ten percent for any one occurrence if the noise is intermittent and during daylight hours. The noise levels shall be measured at the parcel boundary;

• C. Sound pressure levels shall be measured at the parcel boundary and shall be measured with a sound level meter and associated octave band analyzer conforming to standards prescribed by the United States of America Standards Institute;

• D. The following graph shall conform to standard units of measurement in accordance with United States of America Standards Institute Code, S-1.11-1966, Appendix A.

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Inyo County, CA

INYO COUNTY CODE

§ 19.24.030

§ 19.24.030

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• E. Within sixty days after the completion of the drilling of a well, all drilling wastes shall be removed from the drilling site and disposed of, in accordance with county and state regulations;

• F. Suitable and adequate sanitary facilities as approved by the county health department shall be installed and maintained in a clean and sanitary condition at all times;

• G. Drilling operations shall be diligently pursued until each well is completed or abandoned. All drilling equipment including derricks shall be removed from the premises within sixty days after completion of any well;

• H. Prior to abandonment it shall be the responsibility of the operator to comply with all regulations of the Geothermal Resources Law of the state in regard to subsurface actions. In addition, the following surface requirements are imposed.

These surface requirements shall also apply when the well or wells go on production and auxiliary facilities are no longer necessary:

1. The derrick and all appurtenant equipment thereto shall be removed;

2. All tank, towers, other surface installations shall be removed,

3. All concrete, pipe, wood, or other foreign materials shall be removed from the drill site to a depth of six feet below grade,

4. All holes and depressions shall be filled and packed with native earth. All waste material shall be removed from the drill site,

5. In agricultural or potential agricultural areas any brine holding ponds shall be purged of brine, the salts shall be removed from the dikes and bottom and the berms leveled to the satisfaction of the county;

• I. All work in preparation of the site for drilling shall be done between the hours of seven a.m. and seven p.m., unless waived by the planning commission;

• J. All unattended well sites shall be enclosed by a steel chainlink type fence, six feet high. There shall be no opening below such fence greater than four inches. The gate shall be placed at a nonhazardous location and shall be locked at all times;

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Inyo County, CA

GEOTHERMAL RESOURCE DEVELOPMENT

§ 19.24.030

§ 19.24.030

• K. Off-street parking shall be provided with not less than five spaces for each well site, unless waived by the planning commission;

• L. All lights shall be directed or shielded so as to confine all direct rays to the site;

• M. The delivery or removal of equipment or material shall be limited to the hours from seven a.m. to seven p.m., except in the case of emergency;

• N. No drill pipe shall be racked or made up except between the hours of seven a.m. and seven p.m. Exception to this is allowed where soundproofing is provided or in case of emergency;

• O. The drilling site shall be treated to eliminate dust and mud;

• P. The operator shall participate in a subsidence and earth movement detection program. The program shall consist of, but not be limited to the following:

  1. The county surveyor shall be the county's designated agent in the subsidence and earth movement detection program,

  2. The operator shall establish a vertical and horizontal control, to be layed out over a grid system (approved by the county surveyor which shall be tied into the coast and geodetic survey by first order leveling techniques,

  3. The operator shall install benchmarks on this grid as directed by the county surveyor. (Benchmarks shall be a two-inch diameter by two and one-half foot length of iron pipe set in concrete with a four inch brass cap),

  4. The initial grid system and setting of benchmarks shall be established, a yearly measurement for subsidence and earth movement shall be conducted and a report of the findings shall be filed with the county surveyor,

  5. This measurement report shall be submitted to the county surveyor on the first county working day of January each year,

  6. Subsequent measurement reports shall be filed yearly until three yearly reports have been filed after the geothermal well has gone into production. After this time, measurement and earth movement reports shall be filed at five year intervals on the first county working day in January with the county surveyor's office,

  7. If any subsidence or earth movement is detected, the county surveyor shall specify the time schedule for measurement and earth movement reports,

  8. If at any time the county surveyor finds that the operator is not following the above procedures, the county surveyor shall have the measurement and earth movement reports done at the expense of the operator;

• Q. The operator shall participate in a hot springs protection program. The program shall consist of, but not be limited to the following:

1. The operator shall locate all known or possible hot springs in the vicinity of the geothermal project and catalogue these on a United States Geological Survey Quadrangle Sheet (1:62,500) and county assessor's map. These maps shall be filed with the planning department,

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Inyo County, CA

INYO COUNTY CODE

§ 19.24.030

§ 19.24.040

2. Along with the above-mentioned maps, a report shall be filed with the planning department that denotes volume, rate of flow, chemical composition, temperature and other pertinent data on the hot spring(s),

3. The initial survey shall take place before the first exploratory well is drilled in the geothermal permit area. Subsequent surveys shall take place at four month intervals during the exploratory drilling,

4. After a conditional use permit for a geothermal production project is issued, hot spring(s) surveys shall be taken at two month intervals for the first two years,

5. After the above-mentioned two years, if no adverse effects have been recorded, the hot spring survey shall be taken at intervals of six months for the following three years,

6. If any adverse effects on the springs are detected, the county planning department shall specify the intervals for which surveys shall be taken,

7. Upon determination that the adverse effects appear to be of a permanent nature, the operator shall be instructed to proceed with a program to return the affected hot spring(s) to its original state.

• (Ord. 239 § 6.30, 1973)

The following production standards shall be used in developing any geothermal production project:

• A. All requirements imposed by the drilling and planning standards shall remain in effect;

• B. All construction work will require a building permit. The fees and procedures will be based on the current county building and safety department practices;

• C. Continuous and intermittent sound shall be controlled to the levels listed under Section 19.24.030D;

• D. Power lines shall be constructed on existing rights-of-way where possible. Efforts shall be made to share existing facilities. Any new power line installations shall conform with county optimum land use and aesthetic requirements;

• E. All on site roads and parking areas shall be paved. On site parking shall be provided for all employees, customers, or clients;

• F. Shrubs, trees, and ground cover shall be planted and maintained according to department of parks and recreation specifications;

• G. All off site collection pipelines shall be buried and shall utilize and share existing rightsof-way. On site collection pipelines shall be painted and/or landscaped to blend with the environment;

• H. The operator shall continue in the subsidence and earth movement detection program as outlined in Section 19.24.030P;

• I. The operator shall continue in the hot springs protection program as outlined in Section

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Inyo County, CA

19.24.030Q. (Ord. 239 § 6.40, 1973)

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Inyo County, CA

GEOTHERMAL RESOURCE DEVELOPMENT

§ 19.28.010

§ 19.28.020