Tom_H
Veteran Member
My topsoil is clay, 1-4' deep. The subsoil is a water impermeable silica-cemented durapan (a specific type of hardpan) that is anywhere from 4'-16' thick. (That's feet, not inches.) Below the durapan is a layer of moist sand several feet or more thick. The theory is that the volcano at Mammoth Mountain exploded 200,000 yr. ago and laid down a layer of silica all over the CA central valley. This stuff leached down and cemented the claypan below it into a concrete like sedimentary rock.
The clay on top of that is younger than the volcanic stuff. The surface is flat and so the top layer of clay turns into muck in winter because the water can't flow away nor downwards. It's horrible for growing most anything except hay, unless it's restructured.
Vintners have discovered that it is fertile, IF you can create drainage. Some use CAT D11-Rs with 8' rippers to rip the durapan in 3 directions and get drainage. After a few years, it starts to recement itself though. One vintner recently took a giant CAT BH (actually a front hoe) on a 20' arm and dug trenches down into the wet sand layer and mixed the various soil types together before refilling the trenches.
I have 5 acres and just want to plant some trees. In the places where the topsoil clay is only 1 ft. thick, (1.5 acres), I need to bust through this hardpan (again, this ain't thin little plowpan, it's 4-16' thick concrete like stuff.) to get some drainage. The D11 is out; it's $5k just for permits and escort vehicles. I'm also checking into big augers, from phone pole sized up to dry well sized. Another option is hiring a construction sized BH to dig through and mix the various soil types.
An option I haven't thought too much about is drilling some narrow holes and sticking explosives down to shatter the durapan. I live in a rural area, but the closest neighbor's house is 250' away and some federally protected vernal pools are also about that far away. Here are my questions: Since all this terror business, do places sell any explosives anymore? Do you have to get permits? If you try to buy any or even ask, do the feds come do their interrogation routine? How much do blasting contractors cost and how do they compute the amount they charge?
The clay on top of that is younger than the volcanic stuff. The surface is flat and so the top layer of clay turns into muck in winter because the water can't flow away nor downwards. It's horrible for growing most anything except hay, unless it's restructured.
Vintners have discovered that it is fertile, IF you can create drainage. Some use CAT D11-Rs with 8' rippers to rip the durapan in 3 directions and get drainage. After a few years, it starts to recement itself though. One vintner recently took a giant CAT BH (actually a front hoe) on a 20' arm and dug trenches down into the wet sand layer and mixed the various soil types together before refilling the trenches.
I have 5 acres and just want to plant some trees. In the places where the topsoil clay is only 1 ft. thick, (1.5 acres), I need to bust through this hardpan (again, this ain't thin little plowpan, it's 4-16' thick concrete like stuff.) to get some drainage. The D11 is out; it's $5k just for permits and escort vehicles. I'm also checking into big augers, from phone pole sized up to dry well sized. Another option is hiring a construction sized BH to dig through and mix the various soil types.
An option I haven't thought too much about is drilling some narrow holes and sticking explosives down to shatter the durapan. I live in a rural area, but the closest neighbor's house is 250' away and some federally protected vernal pools are also about that far away. Here are my questions: Since all this terror business, do places sell any explosives anymore? Do you have to get permits? If you try to buy any or even ask, do the feds come do their interrogation routine? How much do blasting contractors cost and how do they compute the amount they charge?
