Methane dangers in Los Angeles linked to waste disposal in old oilfields

Methane dangers in Los Angeles linked to waste disposal in old oilfields Paper to be presented at Meeting of the Pacific Section Convention American Association Petroleum Geologists and Western Regional Meeting of the Society of Petroleum Engineers Westin Hotel, Long Beach, June 2000 Session: Environmental Liabilities Associated with Oil Industry Operations
Studies of past oilfield hazards in Los Angeles show that the most severe hazards above old oilfields are associated with disposal of production wastes and attempts to give new life to old fields by repressurizing the ground, according to studies by two experts who have analyzed the history of hazards present in the Fairfax and Baldwin Hills areas. “Both the failure of the Baldwin Hills Reservoir in 1963 and the Fairfax Gas explosions of 1985 occurred following initiation of waste disposal or secondary recovery operations by pressure injection of oilfield wastewater back into the fields,” said Douglas Hamilton, a geologist who has been studying these events for the past decade. To an increasing degree much of the fluid that is produced by oilwells in old fields is gassy salt water that has no use and must be disposed of. The discovery in the late 1950s that the waste could be pumped back down into the ground, and that the undergound balloon of pressure would actually force more oil into oil wells was a boon to the oil industry. “But the history of past disasters backed by mathematical modelling studies now show that use of excessive pressure will cause gas and water to burp back up from thousands of feet below the ground,” … The disposal reinjection was into a block adjacent to te Third Street fault which projects to the surface near the surface venting sites. Injection was at surface pressures of up to 770 psi giving rise to a gradient of about 0.7 psi/ft within the subsurface near the point of injection. We conclude that this resulted in episodic fracturing of the Third Street fault. … Clearly the phenomenon of methane venting in the urban environment can be hazardous….

This entry was posted in Global Frac News. Bookmark the permalink.