Sinkhole/Mudslide right in front of 1150H

So I was dozing a road across a canyon that had some clay and a little water, trying to get to the other side which had some rock in it, and it was getting pretty sticky so I backed up onto some road with rock in it, and right when I did the whole canyon sort of opened up and slid down the hill. I uploaded the video:


Notice the tracks where I just was sliding down the hill. This thing continued to slide throughout the next day and is now about 25 feet lower than road grade.

So I guess I'm planning on waiting for things to get a little dryer and then formulate a plan, since I really need to get across this canyon. I'm not really in a hurry. What do you all suggest to avoid more slides and get a stable road across this? It's very steep grade, as you can see on the other side of the canyon in the video.

There is a wet zone with a spring or some runoff feeding into it. It is at the very base of your slippage. You can pile dirt until the cows come home, and it will continue to slip downhill. The real way to fix that is to remove all the dirt down to the base of the slip. Find out where the water is coming from, and control/divert that water. Then start back with your fill. no other approach will fix this for good.
Jeff

Yeah, might have to dig deep into that hillside to get the water out of there, likely there's a layer where its flowing, bring that out to daylight and let it run off over the surface, Looks like a lot of rocks there so a glacier might have left you a surprise!. Advise here always seems to be push the spoils off the shoulder but keep your machine on cut ground not filled ground.

Or bridge it. Have three wet weather and two year round springs on our place, cannot get near the full time springs with anything heavy as is just gushy mud all year. Wet weather springs come and go with rains, I have them marked out and avoid them at all cost, damned near to lost my 180 in one of them last season.

I'll agree with what has been posted already, deal with and control the water or bridge over it.

Is there any stable ground below the area where the slope broke loose where you relocate your road ?

You will want to have a geologist/soils evaluation done on this section of ground, not gonna like the expense but debating here whether have any good ground to work with will accomplish little. There may be other Slippage spots you have not spotted yet and will not be as forgiving as this one was as to warning of slide.

You're braver than I to keep your dozer at the edge of disaster.

I did like the video of the moving ground though ...

I'd still be backing up.

I damn near went off a 300 foot dump one night with a 10 when the toe blew out. It was our "mud" dump and was the depository for everything we mined through that wasn't worth anything. I had about 5 trucks running to me with mud and ice from this face with a huge amount of clear ice in it. Probably very very old. It was about 0 degrees Fahrenheit. The dump was building out as one would expect. 6' foot berms of mud I was spotting trucks, dumping them short and either pushing through or stacking the berms. All things considered the slope repose was holding up pretty well. I had a few minutes when the shovel went down for service and and I took off to crosscut the truck path to the berm face to run out any hidden rock in the slop that may kill a tire. I was a couple hundred feet from where I started and I noticed some motion out of the corner of my eye and turned and looked in time out the cab side window to see the entire berm disappearing beside me. I side-stepped the decelerator and headed for more friendly real estate...fast. It sheared back to the track the machine had left and stopped it blew out about a 60' section. Needless to say I have a huge respect for sloppy hillsides virgin or placed. Be careful with that! I consider myself very lucky. if the whole face would have went, it would have taken sometime to find me.
I have also taken the class on burying water. One mine I was in decided we were going to fill over a small pond instead of draining it then filling. We put about 300 feet of material over that pond in 50' lifts and it followed us all the way up. We were forever screwing with the dump grade as the water pumped up. 30 793's make pretty fine compactors and they will find the pumpy spots in a hurry. I also agree with the above comments.

hosspuller said:

You're braver than I to keep your dozer at the edge of disaster.

Click to expand...

That's exactly what I thought, I've seen stuff like that open up and just keep coming right up the hill.

Hillside sloughed here along our county road, was wild watching it just settle. MODOT not playing, left it lay as it settled.