Mo. Rev. Stat. § 293.040: Maps of mine, when made, contents.

The operator of each mine in this state shall on request of the director make, or cause to be made by a competent engineer, an accurate map of the underground workings of his mine. The map shall bear the name of the mine, its location, the name of the operator, and such other information requested by the director as is necessary for the administration of this chapter.