Tropical wetlands and the presence of indigenous people with an ancient culture and strong economic dependence on natural resources, made the Pedernales field an environmental and social sensitive location. The challenge for BPA was to operate in this area without disrupting the lifestyle of the nearby settlements while preserving the environment.
Pedernales field was designed as a zero discharge operation, where the main was streams were to be re-injected. However, due to operational constraints, the initial waste management strategy had to be changed to one that also allowed the disposal of wastes in an environmentally sound way. Waste recycling, bio-treatment and temporary off site treatment and disposal were the key processes of the new waste management strategy.
During 5 years of operations, a total of approximately 2.6 MM bbl of E&P waste were handled and disposed successfully. Poor area drainage, combined with high annual rainfall and low natural soil supporting capacity, required the use of non-conventional tools and equipment; this was more evident for the disposal of drilling cuttings.
Drilling cuttings were handled by turning them into slurry using a specially designed mixer, and then pumping the slurry to a distance of up to 2 Km from the storage barge. Oil degradation from 6%, oil and grease, down to 1% was accomplished in approximately 180 days. This is considered to be a short time taking into account the high level of soil/waste moisture saturation. Continuous monitoring of water and soil with a simple on-site laboratory proved to be adequate and cost effective for process control and prevent environmental pollution.