Cal. Food & Agric. Code § 33487
No environmental impact report may be required by any state agency for any activity of a dairy farm, including adoption of waste discharge requirements pursuant to Division 7 (commencing with Section 13000) of the Water Code, under all of the following circumstances:
(c) Where a permit for construction has been issued by the appropriate local agency or agencies, and construction undertaken.
This section shall not apply to any dairy that received a permit, and undertook construction, prior to the effective date of the legislation enacting this section.