With introducing dewatering unit has been made lots of efforts to reduce the volume of drilling wastewaters, mud preparation costs and the consumption of fresh water where environment suffers from water shortage through recycling of wastewaters. In this whole research, the efficiency of drilling waste management to prevent organic contaminants in drilling waste from leaking in the environment were monitored. According to the obtained data, not only dewatering effluents have not been efficiently used for mud preparation but also has polluted the numerous areas especially in southwest of Iran. The amounts of Chemical Oxygen Demand (COD) in the wastewaters were far much more than the environmental legislation. COD in wastewater also increased dramatically when drilling fluid shifted from water base mud to oil base mud. Almost all drilling fluids and produced water were rich in chloride ions, sometimes reached saturated level. Dewatering unit just succeeded to reduce Total Suspended Solid (TSS) under standard level. Capsulation of hydrocarbons in oil base mud cutting with cement and sodium silicate was not acceptable, having maximum 25% free hydrocarbons in treated cuttings. Unfortunately, at the end of the drilling operation about 80 per cent of hazardous wastewaters remain at well locations penetrating into the environment. In conclusion, several effective techniques are introduced to address problems of drilling waste management.
Keyword: drilling environmental technologies; waste management; drilling waste; dewatering unit
 J. Gholami-Shiri, D. Mowla, Sh. Dehghani, P. Setoodeh, Exploitation of Novel Synthetic Bacterial Consortia for Biodegradation of Oily-Sludge TPH of Iran Gas and Oil Refineries, J. Environ. Chem. Eng. 5 (2017) 2964-2975.
 M. Mojarad, A. Alemzadeh, G. Ghoreishi, M. Javaheri, Kerosene biodegradation ability and characterization of bacteria isolated from oil-polluted soil and water, J. Environ. Chem. Eng. 4 (2016) 4323-4329.
 M.S. Pereira, C.M. de Ávila Panisset, A.L. Martins, C.H. Marques de Sá, M.A. de Souza Barrozo, C.H. Ataíde, Microwave treatment of drilled cuttings contaminated by synthetic drilling fluid, Sep. Purif. Technol. 124 (2014) 68-73.
 Environmental Protection Agency, Environmental assessment of proposed effluent limitations guidelines and standards for synthetic-based drilling fluids and other non-aqueous drilling fluids in the oil and gas extraction point source category. Environmental Protection Agency, Washington, DC, EPA, 1999.
 S.I. Onwukwe, Adaptation of Thermal Desorption in the Treatment of Oil Based Drill Cuttings, Int. J. Eng. Tech. Res. 2 (2014) 2321-0869.
 Environmental Protection Agency, Development Document for Effluent Limitations Guidelines and Standards for the Organic Chemicals, Plastics and Synthetic Fibers Point Source Category, EPA, 1987.
 Schlumberger solid control handbook, January, 1998.
 P. Ekins, R. Vanner, J. Firebrace, Zero emissions of oil in water from offshore oil and gas installations: economic and environmental implications, J. Clean. Product. 15 (2007) 1302-1315.
 B.R. Hansen, S.H. Davies, Review of potential technologies for the removal of dissolved components from produced water, Chem. Eng. Res. Des. 72 (1994) 176-188.
 F. Ahmadun, A. Pendashteh, L.C. Abdullah, D.R.A. Biaka, S.S. Madaenic, Z.Z. Abidin, Review of technologies for oil and gas produced water treatment, J. Hazard. Mater. 170 (2009) 530–551.
 T.I.R. Utvik, Chemical characterization of produced water from four offshore oil production platforms in the North Sea, Chemosphere 39 (1999) 2593-2606.
 D. Shubo, Y. Gang, C. Zhongxi, W. Di, X. Fujun, J. Neng, Characterization of suspended solids in produced water in Daqing oilfield, Colloid. Surfuce. A 332 (2009): 63-69.
 E.W. Rice, R. Baird, A.D. Eaton, L.S. Clesceri, L. Bridgewater, Standard methods for the examination of water and wastewater Author, American Public Health Association, 2012.
 APHA, AWWA and WPCF; Standard Methods for the Examination of Water and Wastewater, 18th ed., American Public Health Association: Washington, D.C., 1992.
 S. Mishra, J. Jyoti, R.C. Kuhad, B. Lal, In situ bioremediation potential of an oily sludge-degrading bacterial consortium, Curr. Microbiol. 43 (2001) 328-335.
 M. Padaki, R. Surya Murali, M.S. Abdullah, N. Misdan, A. Moslehyani, M.A. Kassim, M. Hilal, A.F. Ismail, Membrane technology enhancement in oil–water separation, A review, Desalination 357 (2015) 197-207.
 D.H. Doyle, A.B. Brown, Produced Water treatment and hydrocarbon removal with organoclay, in: SPE Annual Technical Conference and Exhibition, Dallas, Texas, USA, 1-4 October, 2000.
 S.M. Liu, Z.J. Zhang, M.H. Jiang, Treatment of ASP produced water with hydrophilic fibre ball filtration, J. Harbin Ins. Technol.6 (2007) 837-841.
 J.D. Arthur, B.G. Langhus, C. Patel, Technical Summary of Oil and Gas Produced Water Treatment Technologies, ALL Consulting, LLC, 2005.
 G.L. Millar, J. Lin, A. Arshad, C.J. Couperthwaite, Evaluation of electrocoagulation for the pre-treatment of coal seam water, J. Water Pro. Eng. 4 (2014) 166-178.
 C. Barrera-Diaz, B. Frontana-Uribe, B. Bilyeu, Removal of organic pollutants in industrial wastewater with an integrated system of copper electrocoagulation and electrogenerated H2O2, Chemosphere 105 (2014) 160-164.
 H. Ma, B. Wang, Electrochemical pilot-scale plant for oil field produced wastewater by M/C/Fe electrodes for injection, J. Hazard. Mater. 132 (2006) 237-243.
 M.W. Lim, E.V. Lau, P.E. Poh, A comprehensive guide of remediation technologies for oil contaminated soil – Present works and future directions, Mar. Pollut. Bull. 109 (2016) 14-45.
 R.K. Hommel, Formation and physiological role of biosurfactants produced by hydrocarbon-utilizing microorganisms, Biodegradation 1 (1990) 107-119.
 P. Baldoni-Andrey, N. Lesage, B. Segues, P. Pedenaud, P.L. Dehaene, Impact of high salinity of producedwater on the technical feasibility of biotreatment for E&P onshore applications, in: SPE International Health, Safety & Environment Conference, Abu Dhabi, UAE, 2–4 April, 2006.
 A. Fakhru’l-Razi, A. Pendashteh, L.C. Abdullah, Review of technologies for oil and gas produced water treatment, J. Hazard. Mater. 170 (2009) 530-551.
 M. A. Shannon, P.W. Bohn, M. Elimelech, J.G. Georgiadis, A. Marinas, M. Mayes, Science and technology for water purification in the coming decades, Nature 452 (2008) 301-310.
 Z X. Yang, L. Wang, Ch. Zhang, W. Zou, X. Tan, X. Liu, Ch. Wan, X. Zu, Highly effective in-depth dewatering of excess sludge using methanol, RSC Advances issue 90, 2014.
 S.S. Madaeni, The application of membrane technology for water disinfection. Review paper, Water Res. 33 (1999) 301-308.
 E.T. Igunnu, G.Z. Chen, Produced water treatment technologies, Int. J. Low-Carbon Technol. 9 (2014) 157-177.
 A. Subramani, J.G. Jacangelo, Emerging desalination technologies for water treatment: a critical review, Water Res. 75 (2015) 164-187.
 S. Bordoloi, B. Basumatary, Phytoremediation of hydrocarbon-contaminated soil using sedge species, phytoremediation Springer (2015) 279-282.
 V. Tripathi, L.F. Fraceto, P. Abhilash, Sustainable clean-up technologies for soils contaminated with multiple pollutants: plant-microbe-pollutant and climate nexus, Ecol. Eng. 82 (2015) 330-335.
 S.Y. Oh, D.S. Shin, Treatment of diesel-contaminated soil by fenton and persulfate oxidation with zero-valent iron, Journal Soil and Sediment Contamination: An Int. J. 23 (2014) 180-193.
 M.K. Sherwood, D.P. Cassidy, Modified Fenton oxidation of diesel fuel in arctic soils rich in organic matter and iron, Chemosphere 113 (2014) 56-61.
 H. Han, Y.J. Lee, S.H. Kim, J.W. Yang, Electrokinetic remediation of soil contaminated with diesel oil using EDTA–cosolvent solutions, Separ. Sci. Technol. 44 (2009) 2437-2454.
 C.S. Jeon, J.S. Yang, K.J. Kim, K. Baek, Electrokinetic removal of petroleum hydrocarbon from residual clayey soil following a washing process, Clean: Soil, Air, Water 38 (2010) 189-193.
 S.W. Park, J.Y. Lee, J.S. Yang, K.J. Kim, K. Baek, Electrokinetic remediation of contaminated soil with waste-lubricant oils and zinc, J. Hazard. Mater. 169 (2009) 1168-1172.
 D. Rushton, A.E. Ghaly, K. Martinell, Assessment of Canadian regulations and remediation methods for diesel oil contaminated soils, Am. J. App. Sci. 4 (2007) 465-478.
 V. Bucala, H. Saito, J.B. Howard, W.A. Peters, Thermal treatment of fuel oil contaminated soils under rapid heating conditions, Environ. Sci. Technol. 28 (1994) 1801-1807.
 H. Sui, Z. Hua, X. Li, H. Li, G. Wu, Influence of soil and hydrocarbon properties on the solvent extraction of high-concentration weathered petroleum from contaminated soils, Environ. Sci. Pollut. R. 21 (2014) 5774-5784
 M. Han, G. Ji, J. Ni, Washing of field weathered crude oil contaminated soil with an environmentally compatible surfactant, alkyl polyglucoside, Chemosphere 76 (2009) 579-586.
 A. Silva, C. Delerue-Matos, A. Fiuza, Use of solvent extraction to remediate soils contaminated with hydrocarbons, J. Hazard. Mater. 124 (2005) 224-229.
 K. Urum, T. Pekdemir, Evaluation of biosurfactants for crude oil contaminated soil washing, Chemosphere 57 (2004) 1139-1150.
 R. Al-Maamari, A. Hirayama, M. Sueyoshi, O. Abdalla, A. Al-Bemani, M. Islam, The application of air-sparing, soil vapor extraction and pump and treat for remediation of a diesel-contaminated fractured formation, Energ. Source Part A 31 (2009) 911–922.
 C. Lee, J. Lee, W. Jang, Y. Jeon, K. Lee, Evaluation of air injection and extraction tests at a petroleum contaminated site, Korea, Water, Air, Soil, and Pollution 135 (2002) 65-91.
 G. Park, H.S. Shin, S.O. Ko, A laboratory and pilot study of thermally enhanced soil vapor extraction method for the removal of semi-volatile organic contaminants, J. environ. Sci. heal. Part A 40 (2005) 881-897.
 T. Tsai, C. Kao, Treatment of petroleum-hydrocarbon contaminated soils using hydrogen peroxide oxidation catalyzed by waste basic oxygen furnace slag, J. Hazard. Mater. 170 (2009) 466-472.
 J. Drelich, D. Leliński, J. Hupka, J.D. Miller, The role of gas bubbles in bitumen release during oil sand digestion, Fuel 74 (1995) 1150-1155.
 J. Masliyah, Z.J. Zhou, Z. Xu, J. Czarnecki, H. Hamza, Understanding water-based bitumen extraction from athabasca oil sands, the Can. J. Chem. Eng. 82 (2004) 628-654.
 L.L. Schramm, E.N. Stasiuk, D. Turner, The influence of interfacial tension in the recovery of bitumen by water-based conditioning and flotation of Athabasca oil sand, Fuel Process. Technol. 80 (2003) 101-118.
 T.J. Mason, Sonochemistry and sonoprocessing: the link, the trends and (probably) the future, Ultrason. Sonochem. 10 (2003) 175-179.
 M.J. Rijkenberg, C.V. Depree, Heavy metal stabilization in contaminated road derived sediments, Sci. T. Environ. 408 (2010) 1212-1220.
 L. Di Palma, P. Ferrantelli, C. Merli, F. Biancifiori, Recovery of EDTA and metal precipitation from soil flushing solutions, J. Hazard. Mater. 103 (2003) 153-168.