This report describes several ways in which drilling wastes have been injected into underground
formations for permanent disposal. Examples of these methods include waste injection into salt
caverns, injection during plugging and abandonment of wells, injection to formations at
pressures lower than the formations fracture pressure (subfracture injection), and injection at
pressures exceeding the fracture pressure (referred to as slurry injection in this report). The
report focuses on slurry injection technology, how it is conducted and monitored, the geological
conditions that favor slurry injection, and its costs. A database describing more than 330 actual
slurry injection jobs is included as an appendix to this report. |