Land Application of Oil-Based Drilling Mud As a Means of Disposal.

With the explosion of oil and gas drilling across the United States, there has come to be an abundance of Oil-Based drilling mud (OBM). OBM is a by-product of deep and horizontal drilling and is produced through the use of diesel to help lubricate the bit, seal formations and suspend cuttings. One way of eliminating mass amounts of OBM is by land application. This allows microbes in the soil to consume the hydrocarbons and process into CO₂ and H₂O. When land applying OBM, there is a risk of accumulating an excess amount of Total Petroleum Hydrocarbons (TPH), which can be detrimental to plants and soil. Due to this threat, the Oklahoma Corporation Commission (OCC) has set threshold levels for TPH at 40,000 lbs/acre.  The objective of this experiment is to monitor the degradation of TPH after land applying OBM to native rangeland. Different bulking agents such as lime, gypsum, caliche, and manure was mixed with the OBM at different ratios. TPH degradation, plant yield, and soil properties was monitored. Bulking agents will be mixed with the OBM at a 3:1 and 1.5:1 ratio and compared to OBM alone application and a control. Soil TPH and soil properties such as N, P, K, pH, and EC was analyzed at 7, 45, and 60 days after application. Plant yield was measured at day 60.  At day 45, TPH had decreased by 65%-97% for all treatments. There were also no significant differences in TPH degradation based upon the different ratios of bulking agents with OBM. No major changes in soil pH, N, P, and K were found. No significant differences in plant yield between treatments. Further results will be discussed.