... to 22.4 per cent Primary recovery amounted to 22.4 per cent of the 11 million bbl oil originally in place while secondary recovery to June 1, 1968, was 12.3 per cent. A remaining 4.1 per cent is expected to be recovered under current operations even though the field has been producing at water cuts above...

... of primary depletion history. Primary recovery of 180,000,000 bbl from 24,500 productive acres of Chester sands will be greatly enhanced by the current waterflood operation. Waterflood exploitation was begun in 1950. After flood ability was demonstrated, an expansion program was begun and by June 1, 1957...