Arizona law requires excavators to mark and coordinate digging work

Excavators, local jurisdictions, and underground facility operators coordinate marking and excavation for large projects. These rules cover large excavation projects and the affected underground facility operators and local jurisdiction. A large project exceeds one mile of linear excavation, covers at least one-quarter square mile, or is expected to last more than 90 days. On-site development on a previously undeveloped parcel is excluded. If the parties do not agree on a schedule, markings must be completed within 15 business days after the marking request. Excavators must notify the one-call center at least 15 business days or 21 calendar days before the proposed start date.

Excavators mark the planned dig area in white before requesting utility locations, and use the one-call center's online system for locate status and other required communications. The white-lining rule applies to excavations other than the stated single-family-home exception, including large projects and work on other single-family properties. The white-lining rule does not apply to a person excavating on a single-family home that the person owns or occupies. An excavator may begin after receiving all affected operators' responses through the system.

Landlords respond to excavation inquiries and mark facilities they operate in apartment communities and mobile home parks. The marking duty covers facilities operated by landlords in apartment communities and mobile home parks, including certain connected facilities not operated by a public utility or municipal corporation. If a landlord does not respond, an excavator may proceed only after giving written notice one working day ahead, checking for visible signs of unmarked facilities, locating known facilities, and protecting them. An excavator must not proceed if the landlord responds that it intends to comply, even if the response will be late. Landlords must respond within 10 working days after receiving an inquiry.