"A modified in situ oil-shale process. the Oxy process, has both economic and environmental advantages compared with aboveground processing. The Oxy process, which recovers a higher percentage at oil than do aboveground retorting processes produces sufficient water for its operations, minimizing the effect on agricultural conditions in the semiarid land where the U. S. oil shale is prevalent. The reduction of the mining required will necessitate fewer people than does the equivalent production of shale oil from aboveground retorting processes. After three successful in situ retorting experiments under actual field conditions. Occidental has now constructed a commercial scale in situ retort. which has a cross sectional area approximately 14,400 square feet and a depth of over 250 feet."