Dexpan?

[drewnje]

We need a 5' soil buffer for a landfill that is to be build, unfortunately the bedrock in some places may be too shallow and need to be excavated out. We would like to avoid blasting and have recently come across info on dexpan for rock demolition. I have seen the demonstrations on the internet, but was wondering if anyone had any experience with it.

 

[miningman]

Works very well if used correctly. Personally I wouldnt use holes smaller than 1.25 inch diameter. Drilling holes at any thing less than vertical reduces the effectiveness of the stuff, and try to lay out your hole pattern so that the " loaded " holes have a mininum of one , preferably two free faces to break to.

Give it time , it might appear to have stopped working after 24-48 hours but its surprising how much more work you can get out of the stuff 72 hours later

 

[drewnje]

Do you have any idea how it compare in cost to blasting?

 

[miningman]

Way more expensive, at least a 10:1 ratio. If you have a semi substantial volume of rock , bring in a blasting contractor.

This stuff is only cost effective in areas where blasting is impractical...... in a building basement , under a power line , middle of a residenmtial area as examples , and even then , people like myself can safely blast using blast mats etc... its just the perception that worries non explosive personnel.

Whats the approx volume of rock you are dealing with?

 

[drewnje]

Thats the problem, we aren't sure how much rock will need to be removed. We developed a top of rock map based on our best data, but that data was significantly limited. Also, the area we are working in is in the remnants of an old mine so the bedrock is quite variable. We could have several places within a 4 acre area that may need to be removed, as far as size we don't know until we get down to them.

 

[miningman]

Sounds like blasting is the way to go