1 EXHIBIT 11.1 CLEAN HARBORS, INC. AND SUBSIDIARIES COMPUTATION OF NET INCOME PER SHARE FOR THE THIRD QUARTER ENDED SEPTEMBER 30, 1994 (in thousands) THREE MONTHS ENDED NINE MONTHS ENDED SEPTEMBER 30, SEPTEMBER 30, ---------------- ---------------- 1994 1993 1994 1993 ------ ------ ------ ------ Net income (loss) $ (138) $ 275 $1,710 $2,550 Less preferred dividends accrued 117 100 329 250 ------ ------ ------ ------ Adjusted net income (loss) $ (255) $ 175 $1,381 $2,300 ====== ====== ====== ====== Earning per common and common equivalent share: Weighted average number of shares outstanding 9,431 9,426 9,429 9,404 Incremental shares for stock options under treasury stock method 162 402 220 697 ------ ------ ------ ------ Weighted average number of common and common equivalent shares outstanding 9,593 9,828 9,649 10,101 ====== ====== ====== ====== Net earnings (loss) per common and common equivalent share $ (.03) $ .02 $ .14 $ .23 ====== ====== ====== ====== Earnings per common and common equivalent share - assuming full dilution: Weighted average number of shares outstanding 9,431 9,426 9,429 9,404 Incremental shares for stock options under treasury stock method 162 402 220 697 ------ ------ ------ ------ Weighted average number of common and common equivalent shares outstanding - assuming full dilution 9,593 9,828 9,649 10,101 ====== ====== ====== ====== Net earnings (loss) per common and common equivalent share - assuming full dilution $ (.03) $ .02 $ .14 $ .23 ====== ====== ====== ======