Grand Ronde Benchmark is on Weyerhaeuser property and requires a recreation permit for access which has a limited number avalible and has a cost (Black Rock is the permit area). You can find info here. https://recreation.weyerhaeuser.com/Permits. Access via Fire Hall Rd. in Grand Ronde.
I approached from Duffy lake Trailhead. As I did Red Butte on the this trip. http://www.pnwsota.org/blog/kf7sey/2021-july-12/red-butte-or-july-2021. This area requires a Central Cascades Wilderness Permit.
Start at Duffy Lake trailhead. https://www.fs.usda.gov/recarea/willamette/recreation/recarea/?recid=4296
Start by going through Falls City crossing the brige to Chamberlain road which will turn into Valsez road. Now this is a long trip on logging roads out and back. Over 40 miles round trip. Follow signs as if you were going to Valley of the Giants. https://www.oregonhikers.org/field_guide/Valley_of_the_Giants_Trailhead
Take Mill Creek Rd off of Highway 22. Once you go through the gate travel roughly 8.5 miles till you reach Shumway. (Stay on Mill creek all the way to Shumway). Take that left at (44.9555 -123.5728416).
Take Mill Creek Rd off of Highway 22. Once you go through the gate travel roughly 4.5 miles till you reach Wind Creek. Take that left at (44.968056 -123.503611). You can somewhat follow the path by watching my You tube video of the trip. It is a bit blurry but should help with navigation. https://youtu.be/88NWG_YNq7o.
Bald Mountain has been a great activation in the past for me. Still is just is a little more difficult. The way before is not accessable now due to Hancock who owns most the area keeps there gates closed and only allows non-motorized access. Easist way to aproach now is via Falls City on Valsetz Road. follow Valsetz Mainline for roughly 7.5 miles. Remember this area is closed during fire season. After roughly 7.5 miles you will find 1500 road on the left at 44°49'21.73"N 123°32'2.15"W (44.822703° -123.533931°). Follow this road for about 3 miles and will come down a steep hill.
Taking Gooseneck Rd off of Highway 22. Same approach as nearby Dorn Peak W7O/CC-013 http://www.pnwsota.org/blog/ki7emx/2017-december-10/dorn-peak-oregon
Once you leave pavement on to gravel, follow road for 2.4 miles. You will come to an 3 way intersection at 44°59'16.96"N 123°30'32.75"W (44.988044° -123.509097°). Turn left here. If you are going to Dorn Peak take the right - it will take you all the way to the summit.
Easiest way to get there is from highway 22. From there take SW Little Hebo Rd. (NF-2234) - near milepost 14 and next to the Suislaw National Forest sign. 45° 5'45.80"N 123°44'38.52"W.
Travel on this for about 5.5 to 6 miles. The road actually travels right near the summit. GPS works well for navigation on this one. On the summit there is plenty of room to setup antennas in several large laydown areas.
If you want you can get to Mount Hebo W7O/NC-006 from here relatively easy.
Chandler Mountain is near the old Valsetz town site and pond (https://en.wikipedia.org/wiki/Valsetz,_Oregon). This is the first summit I activated back in 2012. To get there, head to Falls City 10 miles South-West of Dallas. Once in Falls City, head through town crossing the bridge. Continue untill you reach Chamberlain Road this will turn in to Valsetz Road which will turn into gravel. There is a gate which is closed during fire season. From the gate follow the road for about 12 miles.