Mo. Rev. Stat. § 319.030
1. Every person owning or operating an underground facility to whom notice of intent to excavate is required to be given shall, upon receipt of such notice as provided in this section from a person intending to commence an excavation, inform the excavator as promptly as practical, but not in excess of two working days, unless the excavator agrees to extend the start date and time provided in the locate request through methods established by the notification center, of the approximate location of underground facilities in or near the area of the excavation so as to enable the person engaged in the excavation work to locate the facilities in advance of and during the excavation work, provided that no excavation shall begin earlier than the scheduled excavation date provided on the locate request unless the excavator has confirmed that all underground facilities have been located. The two working days provided for notice in this subsection and subsection 1 of section 319.026 shall begin at 12:00 a.m. following the receipt of the request by the notification center. Each underground facility owner receiving notifications from the notification center by use of the internet shall, after December 31, 2014, use the locate status system provided by the notification center. Those underground facility owners that do not receive notifications by use of the internet shall, no later than January 1, 2016, provide locate status to the notification center by an alternate method provided by the notification center. If the excavator states in the notice of intent to excavate that the excavation will involve trenchless technology, the owner or operator shall inform the excavator of the depth, to the best of his, her, or its knowledge or ability, of the facility according to the records of the owner or operator. The owner or operator shall provide the approximate location of underground facilities by use of markings as designated in section 319.015. Persons representing the excavator and the owner or operator shall meet on the site of excavation within two working days of a request by either person for such meeting for the purpose of clarifying markings, or upon agreement of the excavator and owner or operator, such meeting may be an alternate means of providing the location of facilities by originally marking the approximate location of the facility at the time of the meeting. If upon receipt of a notice of intent to excavate, an owner or operator determines that he or she neither owns or operates underground facilities in or near the area of excavation, the owner or operator shall within two working days after receipt of the notice, inform the excavator that the owner or operator has no facilities located in the area of the proposed excavation. The owner or operator of the underground facility shall make notice to the excavator that no facilities are located in the area of excavation by contacting the excavator by any of the following methods:
(6) By verbally informing the excavator in person.
If the only means of contacting the excavator is one or more telephone numbers provided by the excavator in the notice of excavation under section 319.026, then two attempts by the underground facility owner to contact the excavator at one of the telephone numbers provided shall constitute compliance with this subsection; or
(L. 1976 S.B. 583 § 5, A.L. 1991 S.B. 214 & 264, A.L. 2001 H.B. 425, A.L. 2008 H.B. 1779, A.L. 2014 H.B. 1867, A.L. 2025 S.B. 133)