SAN FRANCISCO (AP) – California regulators say Chevron has not done enough to stop a massive oil spill that dumped about 800,000 gallons of crude oil and water into a Kern County canyon, and they want the company to take further action to halt the flow. The seep out of the ground where Chevron injects steam to extract oil has been happening on and off since May. The state has issued Chevron a notice of violation ordering it to stop steam injections around the area where the seep was occurring. Chevron said the last flow was Tuesday. KQED reports regulators took a further step Friday by ordering the company to completely stop the flow and prevent any new releases. Chevron said it will review the order and work with involved agencies.