Tex. Utilities Code § 141.009

A distribution system retailer shall post, in favor of the commission, financial surety in the form of a letter of credit, bond, or other acceptable form of financial surety with the commission in an amount equal to the lesser of $3 multiplied by the number of gallons of aggregate storage capacity in all of the propane gas systems operated by the distribution system retailer or $50,000. The issuer of the financial surety used to meet this requirement shall honor the financial surety if the issuer receives from the commission notice that the financial surety is due and payable. The commission may draw down all or a portion of the financial surety. The distribution system retailer shall provide the commission with verification of the adequacy of the financial surety, and the commission may order the distribution system retailer to adjust the amount of the financial surety annually.