California Code, Public Resources Code - PRC § 29508

(a) Improvement to existing single-family residences.

(b) Repair, replacement, reconstruction, or maintenance that does not result in an addition to, or enlargement or expansion of, the object of such repair, replacement, reconstruction, or maintenance. However, if the commission determines that certain types of repair, replacement, reconstruction, or maintenance activities involve a risk of substantial adverse environmental impact, it shall require, by regulation, that a permit be obtained under this chapter.

(c) The installation, testing, and placement in service or the replacement of any necessary utility connection between an existing service facility and any other development for which a marsh development permit is required and has been issued pursuant to this division. However, the commission may, whenever it deems necessary, require, as a condition to the issuance of such a permit, reasonable measures for the mitigation of any adverse impacts on marsh resources, including scenic resources.

(d) Any category of development, or any category of development within a specifically defined geographic area, that the commission, by regulation, after public hearings, and by a two-thirds vote of its members, has described or identified and with respect to which the commission has found that there is no potential for any significant adverse effect, either individually or cumulatively, on the resources of the marsh and that such exclusion will not impair the ability of any local government or district or the Solano County Local Agency Formation Commission to prepare its component of the local protection program.