|(a) A locator shall use all information necessary to mark underground pipelines accurately. (b) Locators shall mark the approximate center line of an underground pipeline. (c) If, in the process of marking an underground pipeline, a locator discovers a customer-owned underground pipeline, the locator shall make a reasonable effort to advise the excavator of the presence of the customer-owned underground pipeline. (d) Where a proposed excavation crosses an underground pipeline, markings shall be at intervals that clearly define the route of the underground pipeline, to the extent possible. (e) A locator shall mark underground pipelines by means of stakes, paint, flags, or a combination of two or more of these. The terrain, site conditions, and type and extent of the proposed excavation shall be considered in determining the most suitable means for marking underground pipelines. (f) A locator shall mark at sufficient intervals to indicate clearly the approximate horizontal location and direction of the underground pipeline or pipelines. The distance between any two marks indicating the same line shall not exceed 20 feet; however, a shorter distance between marks may be necessary because of site conditions or directional changes of the underground pipeline. (g) Markings of an underground pipeline greater than six inches in nominal outside dimension shall include the size in inches at every other mark. (h) A locator shall extend all markings, if practical, at least one additional mark beyond the boundaries of the specific location of the proposed work as detailed on the line locate ticket. (i) A locator shall make paint marks approximately eight to ten inches in length and one to two inches in width except when spot marking is necessary. A locator shall make a minimum of three separate marks for each underground pipeline marking.