Just to be a little more clear---Pickup up an envelope at the kiosk on the way in. IF towing unhook and drive thru the c/g to find your spot--look for it being level. Then fill out the envelope info, put $$ in, and return to the entrance to put it in the vault. $4 with pass.

There's a kiosk as you enter the campsite area with envelopes and a locked vault to drop the envelope with your cash payment.

It's a BLM campground with a camp host. There's envelopes and a box to deposit your payment in.

Pay at the iron ranger onsite.

There are envelopes and a pay box at the entrance and usually by the map of the sites.