where can I find a list of wastewater cleaning companies serving the California wine industry?
What are you looking for exactly? Do you want a company who will find a way to treat your wastewater, or a company to pump your wastewater? A company to clean your wastewater treatment system? If you can clarify please.
A good source of information is the document from the wine institute to review management of the waste. Maybe it can gives you some ideas.
Google can be your friend: http://biomicrobicswinery.com/projects/
In 2014 when Napa experienced a 6.0 Earthquake, wine barrels from nearby vineyards broke and the liquid flowed down the drain. At the local treatment plant (NapaSan) they had to divert flows as the incoming wastewater was red with wine. The high alcohol content would have wrecked havoc on the plant's biological process.
However, most vineyards are required to do on-site treatment before discharging to the local sewer treatment plant. The above links should help with your search.