Presented at 2010 AADE Fluids Conference and Exhibition held at the Hilton Houston North, Houston, Texas, April 6-7, 2010.
Drill Cuttings Injection and Monitoring for Remote Pad Drilling Operations at Environmentally Sensitive Sites in Cashiriari, Peru
Abstract
Performance and environmental assurance of cuttings injection programs require monitoring and periodic analysis of injection formation response. Such programs provide operational oversight and the ability to recognize and respond to changes in performance or trends, providing for modification of operating parameters to optimize performance and minimize potential negative impacts. Such a process was implemented on a remote pad in a nature preserve in Peru. The development of gas reserves at Cashiriari has extreme environmental sensitivity and DCI was recognized as a technically and environmentally acceptable alternative for waste management. The paper will discuss the issues encountered during the DCI project at Cashiriari. Higher than anticipated injection pressures were indicative of the regional stress regime and required adjustments with respect to operating parameters and performance expectations. Performance has been contingent on successful inhibition of the reactive clays adjacent to the relatively thin sandy target zones. Projections of closure pressure trends associated with batch injection and predictions of performance and disposal capacity have been possible through continuous performance monitoring. Monitoring operations have allowed for performance improvement and/or minimization of potential problems. The operation successfully injected over 200,000 bbls of cuttings on the first pad through careful management of batch attributes and adaptation to operating realities. Recognition of the need for well designed programs to monitor injection performance is critical for the industry. Operational and environmental assurance derived from such programs provides long term operational viability and social acceptance of cuttings injection as a safe means of waste management.