Gov. Code, § 4216.18

The board shall develop a standard or set of standards relevant to safety practices in excavating around subsurface installations and procedures and guidance in encouraging those practices. When possible, standards should be informed by publicly available data, including, but not limited to, that collected by state and federal agencies and by the regional notification centers. The standard or set of standards are not intended to replace other relevant standards, including the Best Practices of the Common Ground Alliance, but are to inform areas currently without established standards. The standard or set of standards shall address all of the following:

(a) Evidence necessary for excavators and operators to demonstrate compliance with Sections 4216.2, 4216.3, 4216.4, and 4216.10.

(b) What constitutes reasonable care, as required by paragraph (1) of subdivision (a) of Section 4216.4, in using hand tools around subsurface installations within the tolerance zone, considering the need to balance worker safety in trenches with the protection of subsurface installations. As part of determining reasonable care, the board shall consider the appropriate additional excavating depth an excavator should make if either of the following occur:

(1) The subsurface installation is delineated within the tolerance zone but it is not in conflict with the excavation.

(2) The location of a subsurface installation is determined, but additional subsurface installations may exist immediately below the located subsurface installation.

(c) What constitutes reasonable care, as required by paragraph (1) of subdivision (a) of Section 4216.4, in grading activities on road shoulders and dirt roads which may include standards for potholing.