PERTAMINA / Vico Indonesia made the decision to minimize the size of mud pits in order to minimize the environment impact and reduce costs in its onshore drilling operation in East Kalimantan. Vico Drilling use a water base mud for drilling the surface hole and a synthetic oil base mud for drilling the production section. At the time of the decision, all cuttings and mud waste from the operation were dumped into a large pit. Since 1999, new technology has been applied for "reduced pit drilling". The environmental goals were achieved at a cost saving, as the costs are more than offset by cost reductions.
The first stage of the environmental protection project used a combination of additional solids control equipment to recover as much of the liquid phase as possible and improved locations to channel the rainwater. Water-based mud, location drainage, and rainfall were treated using water clarification. This process allowed the clean water discharge from the process to be recycled for the rig operation or disposed to the environment.
The second stage of the project used a special equipment to maximize the recovery of synthetic oil base mud and to reduce the oil content in the cuttings. The cuttings are further processed using bioremediation and landfarming technology to degrade the toxic hydrocarbons to harmless end products on location.
Once the system and waste disposal is proven, the third stage will be for pitless drilling. Depending on the success of the bioremediation, the requirement for other advanced technology such as thermal desorption will be evaluated.
During the project, special effort has been given to confirm the water clarification and remediation results. In order to meet Indonesia regulations and other applicable regulations and standards, water and solid waste are tested to ensure discharges are acceptable. The remediated soil area has been planted with a variety of native plants.
Using the above technology PERTAMINA / Vico Indonesia have minimized the environmental impact in its drilling operation. There is a cost saving as the cost of the service is offset by reduced costs for land, construction, reclamation, and re-greening.