NEW OPPORTUNITIES FOR RE-USE OF PRODUCED WATER - WATER QUALITY AND PERMITTING ISSUES

Treatment of produced water for re-use, instead of re-injection is driven by economic and environmental incentives realized by the oil and gas industry. Federal and state regulations have been established to protect the environment from improper disposal of this waste water. Lawmakers in New Mexico have recognized the potential for re-use of produced water as noted by the recent passage of Senate Bill 313 in the 2004 New Mexico Legislature which increased the options for produced water disposal in the state. New Mexico House Bill 388 in 2002 established a tax credit for treating produced water and delivering it to the Pecos River.

The National Pollution Discharge Elimination System (NPDES) permit program requires all discharges into surface waters be permitted by the EPA or approved state programs, to maintain water quality of the receiving waters. In addition to meeting the NPDES permit requirements for any direct discharge of produced waters, disposal of oil and gas waste water is also regulated by various state agencies. In New Mexico, disposition of produced water is regulated by the Oil and Gas Conservation Division (OCD) of the New Mexico Energy, Minerals and Natural Resources Department. The OCD is to regulate the “direct surface or subsurface disposal of the water, including disposition by use in drilling for or production of oil or gas, in road construction or maintenance or other construction, in the generation of electricity or in other industrial processes, in a manner that will afford reasonable protection against contamination of fresh water supplies designated by the state engineer”. This modification of the previous regulation allows for re-use in various industries. Treatment options are now able to target specific industry requirements. For example, re-use of produced water in the oil and gas industry will require water quality that will not foul or interfere with drilling or fracing operations. In contrast, the electric power industry is concerned with total dissolved solids and chlorides due to scaling and corrosion. For use in the agricultural industry or direct surface disposal, nondegradation of the land and receiving waters is critical. This paper summarizes current state and federal regulations, along with specific industry criteria; providing treatment effluent limits as a function of the desired end-use.