Exhibit 11 CLEAN HARBORS, INC. AND SUBSIDIARIES COMPUTATION OF NET INCOME PER SHARE FOR THE THIRD QUARTER ENDED SEPTEMBER 30, 1995 (in thousands) Three Months Ended Nine Months Ended September 30, September 30, ------------------ ----------------- 1995 1994 1995 1994 ------------------ ----------------- Net income (loss) $(1,200) $ (138) $(1,587) $1,710 Less preferred dividends accrued 112 117 335 329 ------- ------ ------ ------ Adjusted net income (loss) $(1,312) $ (255) $(1,922) $1,381 ======= ====== ====== ====== Earnings per common and common equivalent share: Weighted average number of shares outstanding 9,435 9,431 9,433 9,429 Incremental shares for stock options under treasury stock method -- -- -- 220 ------- ------ ------ ------ Weighted average number of common and common equivalent shares outstanding 9,435 9,431 9,433 9,649 ------- ------ ------ ------ Net earnings (loss) per common and common equivalent share $(.14) $(.03) $(.20) $ .14 ======= ====== ====== ====== Earnings per common and common equivalent share - assuming full dilution: Weighted average number of shares outstanding 9,435 9,431 9,433 9,429 Incremental shares for stock options under treasury stock method -- -- -- 220 ------- ------ ------ ------ Weighted average number of common and common equivalent shares outstanding - assuming full dilution 9,435 9,431 9,433 9,649 ======= ====== ====== ====== Net earnings (loss) per common and common equivalent share - assuming full dilution $(.14) $(.03) $(.20) $ .14 ======= ====== ====== ======