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CleanHarbors Press Release Clean Harbors Announces Second - Quarter 2021 Financial Results • Achieves 30 % Increase in Q2 Revenues to $ 926.5 Million • Delivers Q2 Net Income of $ 67.1 Million , or EPS of $ 1.22 , with Adjusted EPS of $ 1.19 EXHIBIT 99.1 • • • • Reports Q2 Adjusted EBITDA of $ 187.8 Million , a 36 % Increase ; Margin Improves by 80 Basis Points to 20.3 % Unveils Incineration Expansion Plan at Kimball , Nebraska Facility Where New State - of - the - Art Kiln will be Constructed Announces Plans to Acquire HydroChemPSC for $ 1.25 Billion ( See Separate News Release Issued Today ) Raises 2021 Adjusted EBITDA and Adjusted Free Cash Flow Guidance NORWELL , Mass . - August 4 , 2021 - Clean Harbors , Inc. ( " Clean Harbors ” ) ( NYSE : CLH ) , the leading provider of environmental and industrial services throughout North America , today announced financial results for the second quarter ended June 30 , 2021 . " Our second - quarter financial results far exceeded our guidance , as we benefitted from a steady flow of high - value waste streams into our disposal network and a strong performance within our Safety - Kleen Sustainability Solutions business , " said Alan S. McKim , Chairman , President and Chief Executive Officer . " These factors , coupled with a rebound in demand for many of our service offerings , drove substantial revenue growth and the highest second - quarter Adjusted EBITDA , Adjusted EBITDA margin and adjusted free cash flow in the Company's history . Positive underlying market trends helped generate growth across all key lines of business . " Second - Quarter 2021 Results Revenues increased 30 % to $ 926.5 million from $ 710.0 million in the same period of 2020. Income from operations grew 83 % to $ 110.0 million from $ 60.2 million in the second quarter of 2020 . Net income was $ 67.1 million , or $ 1.22 per diluted share . This compares with net income of $ 29.0 million , or $ 0.52 per diluted share , for the same period in 2020. Adjusted for certain items in both periods , adjusted net income was $ 65.4 million , or $ 1.19 per diluted share , for the second quarter of 2021 , compared with adjusted net income of $ 28.9 million , or $ 0.52 per diluted share , in the same period of 2020. ( See reconciliation tables below ) Adjusted EBITDA ( see description below ) increased 36 % to $ 187.8 million from $ 138.3 million in the same period of 2020. Benefits from Canadian and U.S. government assistance programs accounted for $ 5.2 million of contributions in the second quarter of 2021 compared with $ 23.4 million in the same period of 2020 . Clean Harbors • 42 Longwater Drive • PO Box 9149 • Norwell , Massachusetts 02061-9149 • 800.282.0058 • www.cleanharbors.com