As used in this part:
Further, nothing in this part shall apply, or be construed to apply, to any employee who performs work to be done at the site of the construction, alteration, painting, or repair of a building, structure, or other work (as these terms have been construed under Section 8(e) of the Labor Management Relations Act, 29 U.S.C. Sec. 158(e)) or logging or timber-clearing operations in initial preparation of land for farming, or who does land leveling or only land surveying for any of the above.
As used in this subdivision, "land leveling" shall include only major land moving operations changing the contour of the land, but shall not include annual or seasonal tillage or preparation of land for cultivation.
Ca. Lab. Code § 1140.4