(ShareCast News) - AIM-listed oil development and production company Nighthawk Energy has received approval on one injector well and has begun the injection of water at its water flood pilot project at Arikaree Creek in Colorado.The group had announced delays to the project on 1 November, but on Friday it said it has performed remediation work on the two injection wells to rectify the pressure drain-offs.The second well is expected to be approved during the course of next week, with injection set to begin shortly thereafter.The flood project had initially been scheduled to begin operations in late October.At 1100 GMT, Nighthawk shares were up 35% to 1.40p.