Geothermal/Wastes Hazardous or Solid

Jump to: navigation, search

Geothermal Wastes Hazardous or Solid

Wastes Hazardous or Solid
Present, Potentially Affected

Hazardous and solid wastes have high toxic ramifications to humans, plants and animals when metabolized, inhaled or touched. Federal, state and local regulations mandate the use, concentrations, transportation, and disposal of these materials. Ample staff training to handle waste decreases the amount of accidents at a work site and decreases the response rate to a site when emergency assistance is needed. Specific emergency protocols such as accident, fire, injury, spill or discharge, and hydrogen sulfide contingency plans are typically included in the overall Operations Plan. These plans treat each emergency with appropriate mitigation measures to decrease risks and damage onsite.

Wastes Hazardous or Solid Impacts & Mitigation

Contaminants and accidental spills are possible with geothermal development; however knowing the impacts associated with these situations aids in appropriate mitigation techniques. Typical impact and mitigation measures are:

Spillages:

  • Develop a Spill Prevention, Control, and Countermeasures Plan that includes employee training for spill prevention and cleanup methods.
  • Avoid harmful additives such as chromate or other heavy metals.
  • Clean up chemicals, fuels, oils, lubricants, or noxious fluids spills immediately with a spill contaminant absorbent. The spilled fluid will be moved off-site to an approved disposal facility.
  • To mitigate fuel spills, designate fueling and and routine equipment maintenance areas.
  • Place absorbent pads or sheets under potential spill sources. To decrease the emergency response rate of leaks, or chemicals and petroleum spills, spill kits will be present for the entire duration of the project.

Storage:

  • Store hazardous materials in separate containers to prevent accidental mixing, drainage or spillage.
  • Avoid draining hazardous materials in streams, drainage areas or on the ground.
  • Additional chemical and petroleum/oil storage areas will be constructed during drilling operations.

Disposal:

  • Transport solid waste such as paper, plastic and other garbage offsite to an authorized landfill facility.
  • It is not permissible to bury or burn solid waste.
  • Portable toilets will be removed and disposed of off-site.
  • State-permitted septic systems will treat sewage from the power plant on-site.

Emergency Plans:

  • All plans fall into the category of accident prevention, emergency response, or public right-to-know.
  • Plans are comprehensive and guide employees through preventative, anticipatory and response actions specific to potential field emergencies. These topics include, on and off-site hazards (i.e. gas, fire, chemical burns and spills), mitigation measures, emergency procedures, heavy equipment and general employee training, chemical limitations, operation and testing procedures (including well blowouts), local emergency response team parameters, and compliance with federal, state and local regulations.
  • After emergencies, employees will write an incident report for site record.

Chemicals:

  • Pentane, one of the working fluids in the generation cycle, is highly flammable. Since it is used in large quantities, permits may be required.
  • Unsafe hydrogen sulfide levels are possible during well testing. Use appropriate metering to test the air saturation levels and wear protective gear such as mouth protection.
  • Total Petroleum Hydrocarbons are to be stored in fuel reserve tanks and closely managed to mitigate spills or leaks. This chemical also has the potential to exist in mud during well testing and drilling. Dispose of large quantities off-site at an approved facility.

Infrastructure:

  • Construct containment berms around hazardous material storage.
  • Develop drainage systems to divert storm water away from well pads to mitigate water contamination from chemical leaks or accidental spills.

Drilling and Testing:

  • Store drilling mud and fluid in reserve pits.
  • To cool drill bits and remove drill cuttings, a non-hazardous bentonite clay-water-based or polymer-water-based mud lubricator will be used.
  • Case and cement the wells to preserve and separate the well bore from ground water aquifers.
  • To prevent corrosion, adjust mud weight, or control lost circulation, use non-hazardous mud additives.
  • Use directional drilling techniques to decrease the amount of impacted water and waste onsite.
  • Evaporate liquid contaminants at the end of the drilling or testing cycle to then pump the existing materials back into the well or remove and dispose at an approved off-site facility.
  • Plug and abandon wells after testing and drilling as been completed to discourage unauthorized access in or near the well pads.

Reserve Pits:

  • Sample the reserve pit waste for hazardous contaminants. Typical tests may include the Toxicity Characteristic Leaching Procedure, total petroleum hydrocarbons or diesel, oil and grease, pH and heavy metal tests. If found, dispose of contaminants at an approved off-site facility.
  • All remaining materials from evaporation ponds, usually nontoxic drilling mud and cuttings, undergo water quality testing. On Bureau of Land Management (BLM) managed lands, reclamation requires these materials, if nontoxic, to be dried, mixed, spread and buried in the reserve pit.

Herbicides:

  • All herbicides will follow Final Vegetation procedures including application, selection and disposal.

Dirt and soils:

  • To mitigate asbestos fibers and airborne heavy metals during excavation, wear dust abatement protective gear such as eye, mouth and skin protection.
  • When serpentine or mercury based materials are present in excavation, further assessment for other heavy metals will occur. All solid heavy metals will be removed and disposed of off-site. Comply with state and federal regulations and require employee protective gear to decrease potential health impacts