I think we can all assume who took the hose and nozzle and that the manner in which it was done was cowardly. I can see the DFW claiming they never took it and the burden of proof would be on the miner. None the less, I would still file a Citizens Comoplaint, at minimum, based on the circumstantial evidence and collect Affadavits from all those witness to the event. As far as a citizens arrest, i don't THINK, and Im no legal beagle, it would stand up as no one saw the LEO's take the equipment.
Edit:
Here is a link to Citizens Complaint Form for the CDF&W.
https://www.dfg.ca.gov/about/docs/FG-980CitizensReport.pdf
As I said, I am no legal Beagle but I am an LEO and work in Litigations for the "Toughest Beat in the State", hint. I think we should all print a copy and keep it on us and as they try to take our equipment, pull out the form and ask them for their full name and badge number and write it on the form in their presence. Trust me you'll see a golden puddle forming at their feet.
I found this in a USFS manual: To file a complaint of discrimination, write USDA, Director, Office of Civil Rights, 1400 Independence Avenue, SW, Washington, DC 20250-9410 or call (800) 795-3272 (voice) or (202) 720-6382 (TDD). USDA is an equal opportunity provider and employer.