S2's Approach to Exploration and Rehabilitation
The effects on the environment are considered from the first stages of exploration planning so as to minimise the impact on the environment. S2's practices during the planning stage include:
- Choosing sites which will require minimal vegetation clearing
- Using the same drill site for multiple holes when applicable to minimise ground disturbance
- Planning of sites during the initial clearing stage to ensure the stockpiling of topsoil for later use during the rehabilitation process (where the topsoil has to be disturbed)
- Use of drill sumps to contain all water produced and used during the drilling process
- Use of lining in drill sumps to ensure the neighbouring vegetation isn’t exposed to saline water (where saline groundwater is present).
S2 has standard rehabilitation processes for all drill sites and other disturbed areas including access tracks that go beyond the minimum requirements, including:
- Ensuring a drill hole is capped immediately upon completion of drilling and any rubbish is removed before the drill rig leaves the drill site
- Where aquifers are intersected, measures are taken to cement the hole to ensure the aquifer cannot be depleted or contaminate neighbouring aquifers.
- All drill collars are removed or cut to an appropriate depth to ensure they will not interfere with other land users. This is completed on a regular basis and is done as soon as possible after completion of the drill hole (where required, this is completed immediately upon completion of the drill hole)
- Earthmoving machinery is used where necessary to:
- Fill in any excavations (sumps, temporary water dams etc)
- Scarify or rip compacted ground to enable seed germination,
- Recontour the terrain to return it, as close as practicably possible, to the natural state whilst installing control measures to prevent erosion
- Redistribute topsoil and native vegetation back over the disturbed ground
- Block drill access tracks to prevent further degradation through the continued use of vehicles
- Where appropriate, re-seeding, using either seed professionally collected from the immediate locality or commercial seed selected to match the locality. Note, in some environments, experience has shown that the native vegetation does not require re-seeding so long as the topsoil is preserved. However, in the event that a lack of growth is observed upon inspection, re-seeding is undertaken.
- A photographic record is kept for every drill site. This includes photographing before the initial disturbance, once the site has been prepared and then after rehabilitation has been completed. Where appropriate a record of the rehabilitation process over time is maintained
- A register of all rehabilitation activities is maintained
- Regular inspections of rehabilitated ground, including an inspection within the first few months as well as after a year to ensure:
- Native vegetation is regrowing
- No evidence of subsidence associated with hole collapse
- No evidence of erosion
- No evidence of weed infestation
In the event of any adverse finding, appropriate remedial action is undertaken immediately to rectify the issue.
S2 has also demonstrated the ability to adapt to local conditions and the local legal requirements. Examples include:
- Working in Nevada, where due to the potential of intersecting multiple, stacked aquifers, rehabilitation of drill holes included bentonite filling of the entire drill hole with a cement cap to surface. In addition, any aquifers incursions were either cement filled, or where significant cavities were encountered, the hole was isolated by cementing above and below the aquifer, thereby isolating the aquifer.
- While working in the arctic conditions of Sweden and Finland, due to the sensitive nature of the soil and swamp conditions, digging of sumps is prohibited. S2 has adapted its procedures to collect and pump drill cuttings down adjacent drill holes, or use a closed-circuit system that separates the drill cuttings and water, and collects the cuttings in a container that are then removed from site and disposed of at an appropriate facility
- Rehabilitation on salt-lake surfaces within Western Australia. S2 teamed up with a local earthworks contractor to design and implement rehabilitation works on the salt-lake surface using wide tracked bobcats over the soft lake surface.
Minimal forest clearance for Finland drilling
Wide track rigs to minimise impact of
salt lake drilling at Polar Bear