INTRODUCTION During 1968@ the American Petroleum Institute's Committee for Air and Water Conservation conducted a survey to determine actual air and water conservation expenditures of the U.S. petroleum industry for the two years 1966 and 1967 and estimated expenditures for 1968. A report on the results of that survey was published in August 1968. In 1970@ a second survey was made covering actual expenditures for 1968 and 1969@ including estimated figures for 1970. This report combines the results of both surveys. To permit direct comparison of the data from year to year@ the questionnaire format was standardized. Completed questionnaires were received from the corporate offices of 45 companies@ representing 98.3 per cent of the industry's crude oil charge per calendar day (10.7 million barrels). The reported daily industry average was 10.9 million barrels. Of the 45 respondents@ 24 reported processing 50@000 barrels or less each calendar day; 13 operated refineries with the capacity to process 50@000 to 600@000 barrels of crude daily; and 8 processed between 600@000 and 1 million barrels of crude each day. All the questionnaires received were treated as confidential@ and the individual documents were returned to the senders after compilation of the data.