You start by digging a hole.
Well today the crew digging the hole encountered a concrete obstruction. (Its now about 11 am). It looks like a massive footing. Based on early excavation, its more than three feet wide and over two feet deep. Its hard to tell is its cast-in-place or precast. Its a little rough. Maybe its old and weathered. Its not really conforming to the dirt so it must have been formed or cast somewhere else. Was there ever another house on this site? Was this something to do with the old sidewalk? Did something get missed? Was there a retaining wall? A Mausoleum? A utility tunnel? Who knows what this thing is. It seems solid. McGuiver (Pierce) takes the landscaper's pick and pounds a 2-inch home in it and says it feels solid.
How do you plant a tree? Dig a hole, encounter an obstruction, rent a jackhammer to enlarge the hole and plant the tree. Great plan no problem. We'll just rent a jack hammer and dig out enough for the cherry tree to establish some roots, make sure it drains and move on. The tree arrives around 11:30 and Dave the landscaper contractor leaves a short while later to rent the jackhammer. Did I mention that in was cool and crisp today? Well apparently the cooling weather is accompanied by our fist hard frost warning. All of Dave's compressors are out on sites blowing out sprinklers and other irrigation systems. Most hydraulic jack hammers run on air compressors which are now in short supply as everyone wants to drain their irrigation lines ahead of the frost. Fortunately Dave finds a jack hammer he can rent and gets back on site around 1:00.
Things are finally going well for about 15 minutes when there is another knock on the door. What we had thought was solid concrete turns out to be hollow. Its a concrete vault about 9 feet long, 5 feet deep and 4 1/2 feet across. What is it? A cistern? A bomb shelter? Based on a 4-inch pipe on the side of the vault, McGuiver (Pierce) is now calling it a septic tank. If that's what is was we were lucky it was drained when it was taken out of service. It must have been abandoned in place a long time ago. There are no noticeable odors. OK I did not really put my head in there but the guy who climbed in there said it did not smell that bad.
We need to get him out of the hole. Illegal confined space entry. This is not an OSHA site. Its now 2:00 pm. Anyone remember when the Westham neighborhood got sewer? I remember Skip Sydnor telling stories about how Sydnor Hydrodynamics got ran the water supply wells for lots of local neighborhoods including ours. I've seen their old right-of-way on the deed for the house. It never occurred to me to wonder about other utilities. We've had county sewer and water as long as I can remember. Who knew we even had a septic system? Who would have thought it was right were we were planting the cherry tree?
How do you plant a tree? Fist abandon the septic tank you did not know existed.
McGuiver came in and got the phone book and we started discussing concrete suppliers. Who is close and who can get here today? Typically you need to order concrete 24 hours ahead of time. S. B. Cox says they can be onsite at 4:30 with 7.5 yards of flowable fill. Yea Barbie Cox!!! Flowable fill is really a lean concrete without aggregate. Lean concrete does not have as much cement as normal concrete. Flowable fill is a sand mix and does not develop high strength. It should set up enough to support the top of the vault but still be friable enough to dig with a shovel in the first 24 hours. If all goes well we should be able to dig a hole tomorrow without a pick ax. BUT the chute on the truck is only 15 feet long and the hole is 21 feet away from the hole. No way we are getting 7 plus yard of fill into the hole with wheel barrows. McGuiver (Pierce) can't convince S. B. Cox to throw on two extra concrete discharge chute extensions. We assume they are concerned we would overload the hydraulics on the chute. Concrete weights about 150 pounds a square foot and the chute typically flows fairly full with concrete and since its flowing its a dynamic versus static load.
We can't get the truck closer. It has to stay on the driveway because of a pine tree we have been trying to save for years and the new sidewalk McGuiver (Pierce) just installed. McGuiver (Pierce) left the house at about 2:30 to go to home depot for a concrete truck discharge chute extension kit (some design and assembly required). He comes back at about 3:15 with:
- 4 10-ft long 2x6s
- 2 10-ft long 2x12s
- 1 4x8 sheet of 3/4 inch plywood
- 1 lb of screws
- 6 lb of 3-inch double headed nails.
McGuiver (Pierce) adds about 25 gallons of water to the truck and really liquefies the flowable fill. At this point we don't really care too much about strength as about filling the void. The chute extension kit works well and supported the chute at a great angle so the flowable fill could flow right off the truck into the hole. McGuiver (Pierce) estimated the load on the chute extension at about 400 pounds. It takes less than 30 minutes to empty the truck and another 30 minutes for the driver to wash down the truck and get off site.
So how do you plant a tree?
- Dig a hole
- Hit an obstruction
- Jackhammer a hole in the obstruction
- Fill the hole with 7 1/2 yards (about half a ton) of flowable fill
- Let the flowable fill consolidate and set overnight
- Return the next day and dig a hole.
On the way rent a jack hammer, find a concrete sub, hit a hardware store, build a temporary wooden structure to support several hundred pounds of flowable fill. So thats how we plant a tree.
At least that's my story. Why else do you think I would bury 7 plus yards of flowable fill (lean concrete) in a concrete vault in my front yard? Did I did watch Sweeney Todd last night? Was Halloween yesterday? No I just wanted to plant a tree.
First draft to be revised later with photos...
