Although it's named after Big Meadow Creek, this campground primarily lies on the Chiawawa River. There's no fee and from the looks of things, no services. If you're okay with roughing it and you either have the campground to yourself or the neighbors are good, it's not bad. There's a single outhouse that I imagine gets pretty ripe when it's warm. I'm not sure I'd use it. (If you're pooping in the wild, remember you need to be at least 200' from water & dig an appropriate hole for your poop. Pack out your TP.) 

There's a site right on the river that's tiny; it looks like the river bank has eaten away at the site. One of the trees in this site is marked with a mining claim. In other words, DO NOT PAN FOR GOLD HERE. There's a good-sized site next to it. Both sites have trees that'll support a hammock. There are two other sites. The one closest to Big Meadow Creek has the most privacy. 

This campground isn't on the gazetteer I keep in my truck, but there's a sign for it along Meadow Creek Road. From there, take FS Rd 6300 & follow the signs. Coordinates, according to my USGS 7 1/2 map: 47.86813 N, 120.69305 W

NOTE: The US Forest Service web page says this campground is closed. However, there is no gate across the road nor any indication they consider people accessing the campground to be trespassing. If you're considering a stay, it's probably best to contact the Rangers Station first.