Screaming or howling in Lake County, Colorado

I was determined to summit Mt. Elbert, the highest peak in Colorado. I had made 2 previous attempts in 2001 and 2000 and on both attempts I was turned back at 13,000 ft. by weather. I have always gone solo. On this day May 29th 2002 I left the Black Cloud Trailhead at 7:00am solo. I summited Mt. Elbert at 1:45pm. The weather was perfect and unseasonably warm. There must have been very little snow during the winter because there was very little snow left even at summit. I stayed on top for 10 minutes took pictures with my digital camera. My sighting occured around 3:30pm at approximately. 11,500 feet. I was decending and very tired.The trail is not very popular because of its steepness and because it's very rugged in spots. I did not see anyone the whole day. I was traveling on the trail through the only level portion which is a high mountain plateau that lasts maybe 300 yards. The trail hugs an avalanche area to the left and to the right is a pine forest which is moderately dense. As I was walking I heard a fairly high pitched but gutteral cross between a scream and a growl. It must have been heard for miles. I froze in my tracks and unsnapped my holster. I scanned in the direction I thought it originated from but it's hard to tell in the mountains because of echo. I looked to the right first into the forest and saw nothing, then slowly did a 360 scan and now I'm looking back to the forest. At 50 yards I spot the bigfoot. It is standing still facing me approx. 7 feet to 7 1/2 feet tall. I was wearing army camo and I think it had a hard time figuring me out for a few seconds. I was so scared and astonished at what I was looking at I could not move.Then suddenly it turned and ran with a huge stride and it was fast. Its color was black and brown mixed and its fur or hair was thick and matted in spots. It ran like a man except with a slightly haunched upper back and a much bigger and more powerful gait. I lost sight of it in about 10 seconds after it began to run. At this point I pulled my pistol and immediately started cautiously down the trail. My heart was beating so hard I thought it was going to come out of my chest. I could actually hear it beating in my ears.I was no longer tired and the adrenaline was pumping. All the way down the trail I was doing looks over my shoulder and scanning everything. My camera was in my light backpack and I didn't even think about it till I got back to the cabin I rented. I know what I saw and nobody can take that away from me but I didn't dare talk about it until I accidently stumbled upon this website. I hope this helps your research.