Cal. Pub. Res. Code § 21161

Whenever a public agency has completed an environmental document, it shall cause a notice of completion of that report to be filed with the Office of Planning and Research using the Office of Planning and Research’s online process. The public agency is not required to mail a printed copy of the notice of completion to the Office of Planning and Research. The notice of completion shall briefly identify the project and shall indicate that an environmental document has been prepared. The notice of completion shall identify the project location by latitude and longitude. Failure to file the notice required by this section shall not affect the validity of a project.