This is an adventure I do not wish to repeat. I was ill prepared for the trail-less portion of this full Foss River loop. I was alone (two hiking buddies bailed out), lack of sleep (hectic week at work), missing gear (forgot an extra battery that I put into my day pack the previous weekend), and with little knowledge of the terrain (was contemplating on an alternative, instead of researching this very route). It could and should have been better.I planned for a 2-night trip, to fully utilize the labor day long weekend, camping at Chetwoot Lake and Tank Lake. Circumstance changed.
8/31, Saturday. Mostly cloudy, 20% chance of rain. Aurora forecast was at 6 (high enough to be seen from Seattle). Left home late (didn't get home until midnight, due to bus problem). At the last minute, I downloaded the GPS map of the area on my old phone and put it in my pack as a backup. Forgot to take the two sandwiches I made last night. Surprising traffic on Hwy 522 and 2. ~1pm, I finally parked at Necklace Valley TH, after waiting for a group to leave. A lot of cars. The privy was locked. I decided to ditch my Jetboil and a down vest the last minute in the car. Walked towards West Fork Foss River TH. Half way through, I got a ride from a young couple. Started the real hike ~1:30pm.
In less than 5 minutes into the trail, entered Alpine Lakes Wilderness. The West Fork Foss River was bone dry, comical to walk over these mighty bridges.
Jut 40 minutes from TH, entered the camping area by Trout Lake. Many big tents. All in the woods. This photo was taken at the day use area. The trail has occasional views of the valley I was walking in. 
I took the side trail right to Lake Malachite. Fairly steep. After a few minutes, I left my pack by the trail. The lake is quite pretty. More alpine like than the forested Trout Lake. Laughing and jumping. A few kids too.
Next is Copper Lake. Rain started. It's larger. There's a camping area at its south end when you first come to the lake, a less popular camping area in the middle of the lake before the trail takes uphill. There's big waterfall falling down from the lake (you saw it on the way here, however, through trees).
The trail steepens, and goes over a ridge, down to Big Heart Lake. Rain had dissipated. 
Big Heart Lake is deep blue, so is Angeline Lake. Quite an arresting color. Both very large (long). The trail climbs up yet another ridge, again, good view of the valley. I got disoriented following faint boot tracks here. Couldn't tell which lake is which.I didn't reach Chetwoot Lake for the night. When I reached the tarn in the rocks around 5350' (~half a mile before), someone called out to me asking if I were to camp there. I was spooked first, didn't see or even think of seeing anyone here. It was around 8:10pm, getting quite dark. Having gotten lost already once persuaded me to settle down here. After pitching up my tent, cleaned, filtered the water (too shallow), I talked to the couple, Schuyler and Rebecca. They asked where I was heading to. Turns out, they were heading the same way tomorrow too, and probably every one who goes beyond Big Heart Lake is doing this loop. Schuyler generously showed me his 2 overland tracks on his phone. One goes north near Lake Azurite, the other detours north (as shown approximate the purple line on the above map) around Iron Cap. I was told there's a 5" wide high ledge one can walk around 5600'.
The night was a bit too warm for my 20°F sleeping bag. No northern light :( Half of the night sky was cloudy. Still saw some brighter stars reflecting in the tarn.
9/1 Sunday, partly sunny. I slept well enough. Woke up when it was just light out, but my alarm didn't ring. My phone was dead. I then realized that I forgot my spare battery in my day pack. I turned on my backup phone. It kept on rebooting, wasting battery. Once it was settled, I headed out shortly after 7am. Waved goodbye to Rebecca. I got on a faint boot track to the wrong direction. Finally I consulted my phone, and corrected my direction. Didn't take many photos today, trying to save battery. By now, my goal was reduced to Iron Cap Lake.
Saw a couple of tents at Chetwoot Lake. From then on, no trail. Here's where the main problem started. I climbed up a talus field to the western ridge of Iron Cap Mountain. Saw a guy coming down this way, so I figured it was fine. Yes, so far not bad. The lake is a beautiful green. 
Walked along the ridge to the right, circling the lake to its eastern flank, great view of the mountains to the south. Met two kids climbing Iron Cap. At one point, the boy had to go investigate, and came back to fetch the girl's backpack, and then direct the girl to go over. I decided that it was too much for me to handle, so traversing lower than they were (stay on top of the ridge). I fell once here, due to loose rocks. Not sure if this is more dangerous than on the proper ridge. Finally I made to the eastern, flatter ridge, where you can easily climb the mountain proper. However, coming down here is treacherous. There were gnarled trees blocking the view. Below them are loose rocks. At one treed area, I tried 3 times, and fell once (I was holding on a tree limb). I saw some figure down there, something bright orange, so I screamed to that direction asking how he/she made it there. No response. It took me ~2 hours to get down the slope. In the mean time, saw a helicopter flying north, and few more mosquitoes flying around. I finally saw this hiker (whom I asked for directions earlier) more clearly, sitting slouched over his/her knees at the bottom 3rd of a rock slope north of me, with a blackish pack ~10m behind up-slope. The bright orange (maybe) rain cover which I saw first was in between. This person was motionless. I yelled at him/her again repeatedly "are you okay". No response. At this point, I was a bit shaken. I could have ended like this person. Now, I just want to hike out, and call 911, forget about Tank Lakes. However, turning back, over these loose rocks again, is not an option.
Once 3/4 down the slope, I walked eastwards towards a snowfield to replenish water. I was carrying only 1L, to save weight, knowing that there're many lakes/tarns along this route. It took me too long in the rocks that I was dehydrating. Further on, I could see a track. Walked there. Met up Schuyler and Rebecca who detoured north of Iron Cap (probably along the purple line). Told them about the fallen hiker I saw. They didn't see it at all. Lots of plump huckleberry here. Another couple of miles later, we started to see more people, and then Tank Lakes, all the way following the track.Quite a lot of people here, even a ranger watching over from a distance. A couple of more tarns. 4:30pm already. After a short rest, filtered 2L of water, I hiked out north, about 12 miles to TH. Didn't take any photos after. See my 2010 trip on this stretch.
Coming down Tank Lakes is a big boulder field. I wasn't sure which way to go. I don't have any track on my GPS map. So just followed the drainage of Foehn Lake. Later, met 3 ladies going about the same direction. I saw a clearer track on the other side of the valley, framed by red Le Bohn Peak. The ladies said they came up that way, but decided to pick a different route going out. They all had overnight packs, going gingerly. There were faint tracks where we were, so pick and choose. I finally got to Opal Lake, where the trail is more defined. Met a couple coming back to their camp. Told them about the fallen hiker I saw. The trail is to the west of the lake, with no view of the lake. Lots of huckleberry here too.
Emerald Lake has a hut with 3 walls. A lot of people gathered in front, a kid with mosquito net over his head. I almost took a wrong trail here again. Around camping area, there are always too many tracks. The main trail is just west of the hut. I really like Jade Lake. Only one tent. The distant mountain reflects in the lake. From then on, the trail is quite straightforward, except once, where it goes 120 degree backwards over rocks, I missed it. By then it was pitch dark, so took me awhile to find the trail with headlamp. Thanks to the GPS map. I had to go down and cross the river. A substantial bridge, at least here the water is flowing quite swiftly. The rest is easy. I got back to the car a few minutes before midnight!
On the way home, I guess I was too tired, I hit a curb and broke a tire. Spent 1 hour changing the tire, and totally forgot about calling 911.
9/2, Monday. Got home ~3am. Called 911 the next morning ~10am. Talked to more than one person on the phone. A King County sheriff called me back saying that there was a report the previous morning about a deceased hiker at similar location. They sent a helicopter out, but due to wind, it didn't land. I Googled online, found a UW professor died there on Aug 5th, and a 19 year old boy this weekend, but in the area maybe 5-6 miles south of me. Not sure if it's the same person.
An exhausting weekend.
Update: more info about the fallen hiker from nwhikers.net: 28 year-old Vitaliy Fishchuk from Bothell.
