1 Exhibit 11 CLEAN HARBORS, INC. AND SUBSIDIARIES COMPUTATION OF NET INCOME PER SHARE FOR THE THIRD QUARTER ENDED MARCH 31, 1997 & MARCH 31, 1996 (in thousands) THREE MONTHS ENDED MARCH 31, ---------------------- 1997 1996 ------- ------- Net loss $(1,983) $(1,642) Less preferred dividends accrued 112 112 ------- ------- Adjusted net loss (2,095) (1,754) ======= ======= Loss per common and common equivalent share: Weighted average number of shares outstanding 9,817 9,560 Incremental shares for stock options under treasury stock method -- -- ------- ------- Weighted average number of common and common equivalent shares outstanding 9,817 9,560 ======= ======= Net loss per common and common equivalent share $ (.21) $ (.18) ======= ======= Loss per common and common equivalent share - assuming full dilution: Weighted average number of shares outstanding 9,817 9,560 Incremental shares for stock options under treasury stock method -- -- ------- ------- Weighted average number of common and common equivalent shares outstanding - assuming full dilution 9,817 9,560 ======= ======= Net loss per common and common equivalent share - assuming full dilution $ (.21) $ (.18) ======= =======