9. Commitments and Contingencies As of September 30, 2018, the Company maintained letters of credit in the aggregate amount of $63.5 million primarily for the benefit of various insurance companies as collateral for retrospective premiums and retained losses which could become payable under the terms of the underlying insurance contracts. These letters of credit expire annually at various times during the year and are typically renewed. As of September 30, 2018, no amounts had been drawn under the letters of credit. As of September 30, 2018, the Company had commitments to purchase major equipment and make investments totaling approximately $143 million for its drilling, pressure pumping, directional drilling and oilfield rentals businesses. The Companys pressure pumping business has entered into agreements to purchase minimum quantities of proppants and chemicals from certain vendors. The agreements expire in years 2018 through 2022 and in 2042. As of September 30, 2018, the remaining obligation under these agreements was approximately $123 million, of which approximately $10.3 million relates to purchases required during the remainder of 2018. In the event the required minimum quantities are not purchased during certain periods, the Company could be required to make a liquidated damages payment to the respective vendor for any shortfall. On January 22, 2018, an accident at a drilling site in Pittsburg County, Oklahoma resulted in the losses of life of five people, including three of the Companys employees. Lawsuits have been filed in the District Court for Pittsburg County, Oklahoma in connection with the five individuals who lost their lives and one of the Companys employees who was injured in the accident. The lawsuits have been consolidated for discovery purposes under Cause No. CJ-2018-60 (the Litigation). These lawsuits allege various causes of action against the Company including negligence, gross negligence, knowledge that injury or death was substantially certain, acting with purpose, recklessness, wrongful death and survival, and the plaintiffs seek an unspecified amount of damages, including punitive or exemplary damages, costs, interest, and other relief. The Company disputes the plaintiffs allegations and intends to defend itself vigorously. Based on the information the Company has available as of the date of this Report, the Company believes that it has adequate insurance to cover the Litigation. However, if this accident is not fully covered by insurance or an enforceable and recoverable indemnity from a third party, it could have a material adverse effect on the Companys business, financial condition, results of operations and cash flows. The Company is party to various other legal proceedings arising in the normal course of its business. The Company does not believe that the outcome of these proceedings, either individually or in the aggregate, will have a material adverse effect on its financial condition, results of operations or cash flows.