2023 update: You can access North Green Mountain if you purchase a Weyerhaeuser permit https://recreation.weyerhaeuser.com. You will need the “Longview – St Helens” one. If you purchased the non-motorized permit, you can walk or bike (no Ebikes allowed) up up from the “Blue Gate” at the end of China Garden Road which Weyerhaeuser appropriately calls the “Green Mtn N” Gate. If you have the motorized permit, you can use your access key to open the gate and it is a short drive all the way up to the summit, no other gates.
I barely got spots out using SMS with ATT. APRS signals were well received, so although I did not spot with APRS it should be possible. There are communication towers on this summit. I experienced some minimal RFI on VHF, none on HF.
