Background and Explanation
The effects of drilling and its associated activities that are addressed in this Plan include:
- Contamination of ground water, surface water and soils by drilling fluids.
- Reduction in ground water quality by contamination from surface water run-off, other surface water and other ground water sources.
- Fuels and other hazardous substances on drill sites contaminating soils and surface water.
- Accelerated soil erosion*.
- Vegetation removal to create drilling pads and drill rig access.
- Well placement causing adverse drawdown effects on other ground water users.
- Loss of artesian water or aquifer pressure both in the short and long term.
- Flow between previously isolated water bodies.
- Adverse effects on geothermal characteristics.
- Loss of geothermal fluid/pressure both in the short and long term.
- Blow-outs (i.e. uncontrolled well discharges) in geothermal wells.
The effects listed in vi) and v) are addressed in Chapter 5.1 while the remainder of the effects are addressed in this Chapter. The magnitude of these effects is influenced by the physical setting of the site, the scale of the drilling operation, the type of drilling, duration of activity, and the hydrology and water quality at the site. Generally, however, effects are minor where good practices are adhered to.