File a corner record after a boundary monument is disturbed by road construction, per California's monument preservation statute.

Steps

1. Cite California Business and Professions Code Section 8771 (Chapter 15, Article 5, Land Surveyors' Act), which requires monuments controlling subdivision, tract, boundary, road, or survey-control locations to be located and referenced by a licensed land surveyor or authorized civil engineer before construction disturbs them.
2. Confirm text at the official legislature site: https://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?lawCode=BPC&sectionNum=8771.
3. Before construction, reference the monument and file either a corner record or a record of survey with the county surveyor — the choice between the two filing types is the licensed surveyor's or engineer's election, per statute.
4. If a monument could be destroyed, damaged, covered, or disturbed by the project, reset a permanent monument in the new surface or set witness monuments to perpetuate the point.
5. File the required corner record or record of survey with the county surveyor prior to recording the certificate of completion for the construction project — not after.