Project Rio Blanco Backers assure underground blasts to release natural gas compatable with oil shale developments. RMN D 15, 1971 p.12 Environmental statement distributed by Atomic Energy Commission. RMN Ja 14, 1972 p.5 AEC schedules 2 public hearings on Rio Blanco blast. Post F 29, 1972 p.11 Full development of project's natural gas field will cost $1.5 million in taxes. RMN F 16, 1972 p.54