NOTE 19. COMMITMENTS AND CONTINGENCIES Lease Commitments The Company has operating leases with varying terms principally relating to transportation, real estate and equipment. Certain of the Company's lease agreements include renewal options to extend the agreements and certain leases include escalation clauses and/or purchase options. These leases do not contain any financial covenants for the Company. Minimum lease commitments payable by the Company for noncancelable operating leases are as follows: Year Ending August 31, (in thousands) 2020 $ 34,511 2021 27,383 2022 22,074 2023 17,433 2024 10,478 Thereafter 12,938 Total $ 124,817 Total rental expense was $58.2 million , $38.0 million and $37.3 million in 2019 , 2018 and 2017 , respectively. See Note 2, Summary of Significant Accounting Policies , for discussion on the impact of adopting ASU 2016-02, Leases, to the consolidated financial statements in 2020. Legal and Environmental Matters In the ordinary course of conducting its business, the Company becomes involved in litigation, administrative proceedings and governmental investigations, including environmental matters. The Company has received notices from the U.S. Environmental Protection Agency ("EPA") or state agencies with similar responsibility that it is considered a potentially responsible party at several sites, none of which are owned by the Company, and may be obligated under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 ("CERCLA") or similar state statutes to conduct remedial investigations, feasibility studies, remediation and/or removal of alleged releases of hazardous substances or to reimburse the EPA for such activities. The Company is involved in litigation or administrative proceedings with regard to several of these sites in which the Company is contesting, or at the appropriate time may contest, its liability at the sites. In addition, the Company has received information requests with regard to other sites which may be under consideration by the EPA as potential CERCLA sites. Some of these environmental matters or other proceedings may result in fines, penalties or judgments being assessed against the Company. At both August 31, 2019 and 2018 , the Company had $0.7 million accrued for cleanup and remediation costs in connection with CERCLA sites. The estimation process is based on currently available information, which is in many cases preliminary and incomplete. Total environmental liabilities, including CERCLA sites, were $3.6 million and $4.0 million as of August 31, 2019 and 2018 , respectively, of which $1.8 million and $ 1.9 million were classified as other long-term liabilities as of August 31, 2019 and 2018 , respectively. These amounts have not been discounted to their present values. Due to evolving remediation technology, changing regulations, possible third-party contributions, the inherent shortcomings of the estimation process and other factors, amounts accrued could vary significantly from amounts paid. Historically, the amounts the Company has ultimately paid for such remediation activities have not been material. Management believes that adequate provisions have been made in the Company's consolidated financial statements for the potential impact of these contingencies, and that the outcomes of the suits and proceedings described above, and other miscellaneous litigation and proceedings now pending, will not have a material adverse effect on the business, results of operations or financial condition of the Company.