I was in Portland on a business trip and took a day to paddle on Sunday April 12, 2015. A business associate/friend from Portland and I connected with a crew running the Farmlands section of the White Salmon. It was my and his first time on this run. We had around 14 paddlers in the group but split up into smaller groups with groups staying in the vicinity of each other. Everyone made it safely below Lava falls with only a couple flips and rolls. Shortly below Lava my group made it halfway through a long rapid that I would rate a class IV and took eddies. The group below us was out of their boats and signaling us to stop. They were attempting to communicate using hand signals, yelling and whistle blasts. I assumed there was wood in the bottom of the rapid. We held our position and someone made it from downstream coming up river right and told us to get out of our boats. I ferried to river right and started my portage still not knowing what the issue was. Part way down I noticed the pinned boat on river right less than five meters from the shore. This was in the last part of the rapidly moving water at the very end of the rapid and could possibly be considered the run out. The boat was vertically pinned less than half to halfway out of the water. A fallen tree came down from river right into the water perpendicular to the river which was causing the pin. There was a rope coming from river left that appeared to be attached to the boat with two paddlers manning the rope. There was another rope on river right attached to the boat that ran close to perpendicular to the shore and to an anchor on a tree. Several boaters were pulling on the rope and the boat would move but not come free. There was a since of urgency. At this point I was unaware there was boater pinned with the boat and thought it was just a boat recovery. A boater from river left had taken the leadership position and was yelling instructions. He advised a vector pull. I created an anchor further upstream on a tree and we reattached the river right rope to it making it run more parallel to the shore. Another boater utilized a prussic cord to create clip point about halfway between the boat and tree. We clipped in another rope and proceeded with the vector pull with force headed towards river left. The boat eventually came free. When the boat came free is when I realized a paddler was trapped because the first rescuers at the scene continued to work at the pin spot. The paddler did not come free with the boat. At this point I understood the urgency. At this point I also realized the rope coming from river left was attached to the paddler and not the boat. A paddler clipped in live bait style and attempted to reach the pinned paddler. She was able to get to him but unable to free him. The boaters on river left requested assistance on their rope to attempt to pull the pinned paddler out. I grabbed a boat and ferried across along with my business associate/friend to assist them. No amount of pulling would free the pinned padder. We were underneath a rock overhang and I could not see anywhere to create an anchor to set up a z-drag without rock climbing nuts or cams. After suggesting some paddlers should paddle out and call 911 I was advised 911 was already contacted. During this time two paddlers were making attempts free the entrapped paddler via live baiting. Other boaters were attempting to saw through the trunk of the tree with a hand saw. We then attempted to utilize the rope from river left to hook under the entrapped paddlers arms. We were successful in hooking under his arms several times but unable to free him. His arms would flop back upstream but he would not come free. My best estimate at this point was he spent 20 or more minutes under water with no airway. After several unsuccessful attempts to free him looping under his arms the rescue squad arrived on the scene with a chainsaw. They cut the trunk of tree and the entrapped paddler came free. He was still attached to the rope coming from river left and he was guided to an eddy on river right and brought onto shore where the rescue squad began treatment. After unsuccessful attempts to resuscitate the patient, the rescue squad brought in a raft to extract him. Our crew decided to hike out. I met Dennis at the meeting spot for the first time ever before we headed to the river. He was a very nice and jovial man. He went out of his way to be friendly to me and my friend and appeared to be a very kind soul. My heart goes out to his family and friends. Respectfully Submitted, KBS