Power
The power of your position depends on whether you work for a private company, a state agency, or the Federal government. Guess which one wields the most power?
If you work for a mining company as their in-house safety inspector and coordinator, you'll have to be satisfied giving your bosses recommendations and safety updates and then kind of letting them do what they want. After all, they're the ones who pay your salary, so they may expect you to not see those toxic waste barrels if they tell you not to see those toxic waste barrels.
Next up are the state agencies, which are pretty powerful, especially in mining-heavy states like West Virginia and California. However, they only enforce state rules on mines.
If you want to be the big dog in the park, you'll have to become an inspector for the Mine Safety and Health Administration. They don't actually make any of the rules regarding mines, but they enforce them with an iron (ore) fist. They're the ones that get to roll into a mining operation, walk up to the head engineer, and say, "Stop, until I say go."
The most powerful part of your job is your ability to cite mining operations for hazardous conditions (source). That may sound pretty weak, until you consider that "citation" is another word for "fee," and that companies really don't want to pay them. At your certified, professional discretion, you can cite mining operations for everything from leaking toxic waste to improper storage of explosives to making laborers work overtime against regulations.
It's not the most powerful power, but the mine managers do have to follow your directions during inspection, so if you want you can start every sentence with, "I command thee to..." It'll be super annoying for them and you'll feel a whole lot more powerful.