It’s expected that California will develop a “comprehensive” set of laws and rules that will bring awe from all other states and most countries. Here’s one agency that imposes rules and procedures on cannabis farmers: North Coast Regional Water Quality Control Board’s Cannabis Cultivation Waste Discharge Regulatory Program. I think it has to do with water.
It appears that you might get by this hurdle with only around $7500, but it could go as high as $500,000.