A Balanced Approach to Waste Disposal using UFI (Underground Fracture Injection)
Authors: D. Baker Brian , Rieke Herman H. 
Published: December 2007

Most business entities agree that waste production is a misuse of economic resources. It is imperative for industry to properly manage wastes by controlling and disposing liquid and solid residues from manufacturing, processing, and oilfield production operations. In many cases this is not entirely possible owing to economic, regulatory, and process design constraints. For example, by-product waste from oil well drilling operations is inevitable, and originally these residues were either discharged into pits, bodies of water, or in the annular space of wells. All drilling and production wastes can have a significant and adverse impact on the environment. This is due to the manner by which the cutting residues are handled. By increasing their concentration through the process of storing, handling, and transportation, toxic substances are released and will exceed what occurs naturally.

The injection of liquid residues into subsurface formations is a standard disposal practice in the oil and gas industry. During the last fifty years, subsurface injection of liquids has become common a practice in the petrochemical industry, chemical manufacturing, nuclear power industry, geothermal energy, mineral processing, and metal manufacturing and fabrication. Concerns about ground water contamination required that Federal and State environmental regulatory agencies in the mid-1980s set guidelines for the control of waste material being injected into the subsurface. The Wellhead Protection (WHP) Program was a new provision in the 1986 Amendments to the Safe Drinking Water Act. This resulted in a classification system of all injection wells by US Environmental Protection Agency (USEPA), Office of Ground-Water Protection. Injection wells are designated as a Class 1, II, III, IV and V. EPA's major emphasis was to establish primary control parameters: depth, mechanical integrity of the well, and proximity to the underground source of potable water. Ground-water protection is primarily a State responsibility. EPA intends to ensure that States have flexibility in developing their programs, while insuring that these goals and objectives of the law are met.

This paper describes some of the new injection technologies and their applications and problems as applied to mixed wastes (slurries). It will also discuss current environmental concerns, economic considerations and risk management with particular case examples of projects located throughout the US and international arenas. We present a tentative set of guidelines from State, Federal and industrial representatives that represent to the authors a "balanced" approach that ensures safe and efficient management of solid waste disposal. These proposed guidelines fulfill the "spirit" of the environmental statute requirements, which are spelled out by the National Environmental Policy Act, Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), and the Resource Conservation and Recovery Act (RCRA). The guidelines were developed for the specific case of deep well waste disposal using Underground Fracture Injection (UFI) but can be applied to all classes of injection where there is a concern for groundwater quality.