(S. 7): Surface Mine and Reclamation Act of 1975: The vote is on the Mathias amendment to phase out strip mining on steep mountain slopes greater than 20 degrees. In a 1973 Senate study, a survey of landslides in Kentucky showed that 86% of the slides from strip mining were on slopes of 20 degrees or more, and that 3 to 5 acres of land are disturbed for every acre stripped on steep slopes. Environmentalists have attempted to include a 20 degree ban since the first strip mining bill was considered in 1972. The President had no position on the amendment. March 12, 1975. Rejected 28-64. The correct vote is yes.