Start off by searching local. If you don't live in one of those three states you listed, move their with a steady job. You need to be with a few hours drive of where you're prospecting for a mine.
You need a high-clearance 4wd and/or an ATV with winch. The first truck I had when I started was destroyed by prospecting in rough terrain. My new one I bought with manual everything except transmission because I expect the mountains to destroy it too. It's just going to happen.
Learn geology. If you don't know the signs you're looking for, you could trip over a vein and not know it. Once you have a good handle on overall gold geology, start honing in on the spots you're hunting in. Expect to at least one full day every single week out in the field looking for something that looks like a good spot. The easy ones to get to are gotten to. You're looking for spots rarely visited or have some distinct disadvantage to the average prospector.
You're going to work with cyanide. It's a Hobson's choice.
Now let's say you got a place found. Make it easy, it's an adit. On BLM land.
Here's what you've got to consider:
Location: How long will it take you to commute to and from the mine, and from the mine into the working area of the mine itself? We're on BLM land so camping out there is drastically limited to a few weeks total per year. Couple this with vehicle wear and tear. If you need employees, how willing are they to drive to the site, or will you need to drive them out there yourself?
Electrical Usage: How many tens of thousands of watts do you need? How big is the generator you need then? How many gallons of diesel does it burn per day? Is your mine close enough to your processing facility that you need one, two, maybe three large generators? You won't believe how fast you'll run out of watts as you move through the rest of this list.
Ventilation: Only the size and layout of your particular mine will tell you how many cubic feet you need to push through per hour. You'll need exhaust fans as well for clearing the air after every blast both for fumes and for dust. You also need to keep temperatures down inside the mine. Yeah, it's 65 degrees underground, but put two people down there doing physically demanding work and the temps rise in the adit pretty quick. Seen my videos? I'm sweating in a lot of them underground. Also, as temperatures climb, the more likely accidents are to occur. MSHA did a study and anything over 85 degrees really impacts the number of underground accidents.
Lighting: You can get by with headlamps, but regular lighting cuts down on accidents tremendously.
Water: You either don't have enough, or you have too much. You'll need it for processing your ore. You'll need it for dust suppression. You'll need it flowing out of the mine if your mine makes water. If it does, how many gallons per hour? Per day? If you're not mining full time, how much do you have to pump out before you can resume after a 1, 3, 7 day lay off? Can you get the permits for discharge? If you're pumping, how much capacity do you need on the pump? Lines for pumping it out? Storage?
Ground support: It isn't cheap, nor easy to install. Are you using steel? Got a welder? Cutting torch? Enough ventilation in the mine and electrical power to run a welder and your fans and water pumps and lighting at the same time?
Drilling: You using air or electric? Got enough water? If air, how big of a compressor? How much diesel does it drink a day?
Mucking: Electric or air? Now you need a bigger compressor yet. Don't forget barring down loose ore and scaling the ribs.
Transport: Are you still only running the one adit? How are you moving the ore? Trams? Got enough power for an electric or ventilation for a gas? Ore car rail isn't cheap either. My best recollection was $600 per 30' of working length. That's not including the ties, bolts, or any bending you need to do. Do you need to widen your adit to allow empty cars to pass by full or will you have a turntable with an alcove for empty storage
Blasting: You won't move enough rock to make a decent living without this. Where you going to store your supplies? Site security? Training? If you're shooting ANFO, you'll need the right equipment to load the holes. Better keep damn good records of how much you use per day/shift/week and it better come out to what you've purchased. Those numbers don't match and your life just got put on hold while you fight the gov't regulatory agencies AFTER you shell out the fines.
Mine Development: How much rock do you need to move, how many hours per day/week/month/year are you going to invest in nothing related to ore extraction? This can be ground support, cutting raises/winzes, installing track, maintenance, changing out light bulbs for Pete's sake, rodent control, scaling and barring down gangue loosened by blasting, etc, etc.
Processing the Ore: The highest energy usage in the mine whether it be gas or electricity is generally found in the crushing and grinding. Dozens of books have been written on this part of gold mining from the time run-of-mine hits the processing area until it ends up at the refiner or the tailings pile.
Environment: Depending on your mine's location, you might only get to run portions of the year. Is that 10 months? 8 months? Less? Can you pull enough ore out in 2/3rds of the year before winter sets in or water dries up to make it a worthwhile endeavor? Is there a monsoon season that blocks access? Winter roads? Water freezing in the mine or processing plant? How will it affect your equipment?
Surveying: I'm going to throw in core sampling, assaying, and surveying all together. Are you staying on track with your samples drill holes? Did someone run a few blasts on the sill a little off now you have a hump creating a dam or an accidental sump? Is the angle of the adit following the strike of the vein? Are you staying on the dip if cutting a winze or raise?
Reclamation: On BLM land you'll owe up front. When you shut her down, you'll need to make it look like you were never there.
Then there's the usual. Insurance for the business and you/your family. Maintenance. Lost time for accidents. Lost time for safety inspections. Lost time for safety training. A hundred other things.
Enough for now. Making my own head hurt.
