Abstract
A cost effective water runoff management program was required to operate a land drilling rig in accordance with strict environmental regulations in southern France. The water runoff management program would focus on minimizing the consumption of water for the drilling process by collecting, cleaning and recycling waste water. It would also control discharges of waste water to the environment, in terms of quantity and contaminant content. This was complicated by the fact that oil based mud would be required to efficiently drill the highly deviated wells. To ensure success, the drilling contractor, whose personnel and equipment would be performing the drilling work, had to be involved.
The key to the program was a process to collect, clean, and recycle water. A continuous cleansing process was designed, incorporating gravity weir type oil / water separators to remove hydrocarbons and chemical treatment to remove solids.
A drilling location was designed and built, with the cooperation of the drilling contractor and water treatment specialist, to include the recycling process system and collection ditches or berms around all areas and equipment which could discharge contaminated water. Specialized equipment to collect contaminated cuttings was installed.
An incentive scheme was developed for the trilling contractor with a bonus or penalty based on the volume of water discharged and the hydrocarbon content of this discharged water.
The program has been in place for one year with good results. Volume of water consumption was cut in half early in the program and hydrocarbon content of discharged water has been kept at or under 2 grams per cubic meter.
