The site I was drilling at this week, has a bit of a history. It is a gas station that has changed hands a few times; however, underground storage tanks (USTs) which belonged to the previous owner leaked. They are our client, and we are working to clean up that contamination.
Last year it was thought that the site was essentially clean. A remediation system for both vapor and groundwater had been in place, and as extracted concentrations had dropped, the system was shutdown and removed, and a closure report was prepared for the site. As part of the closure report, the county wanted a risk assessment, and so Hooligan and I installed vapor monitoring wells.
These are small wells to about 6 feet bgs, and this version has a small aquarium filter (resembling a large cigarette filter) at the bottom. We attach vacuum canisters to these wells, which then pull vapor out of the ground. These canisters are shipped to a lab who analyzes the vapors, and (for this site) told us that the vapor was very much above the allowable limit which is set by the state and federal governments.
So Hooligan and I went out at the end of last summer, and did some investigative borings. We used a direct-push rig which is louder than a jack hammer, and uses the same principle except it pushes a 1.5-inch diameter 5-foot long tube into the ground to extract soil samples. These soil samples were shipped to a lab,and they told us where the highest concentrations were, and that's where we decided to put the new extraction wells. For the new remediation system. Along the way we bent and cracked road, and never got to our maximum target depth because the ground is so hard.
And that is just leading up to this week.
The crew we were assigned is not my favorite. The driller had run an installation in Sacramento that took too long. And one of the helpers had pissed me off several times before.
Tuesday: My Program Manager decided we needed to attach a sump to the well (3 feet of blank in the bottom), but we hadn't scoped that with the drillers, so we stopped early while they went looking for parts. I was assured by the driller that he cold get the work done in one day and get us caught up.
Wednesday: Things were going fine at first. We finished the first well and hour late (forcing the grout inspector to stand around waiting), and moved on to the second one. And we ended up being on site for almost 11 hours. Helper #1 can't do anything without being told what to do, and the driller would walk off and work would stop for no reason.
Thursday: We knew there was record heat coming in, we've got one well to go... And they had brought two 10-foot sections of the wrong sized well-screen. Schedule 80 when we wanted schedule 40. So they had to go to the supply store again, and we stopped work.
Friday: We've only got a few tasks today: ream the hole out with the larger augers and set the well. Maximum, this should have taken 6 hours. And instead, the day took 8 hours. We were setting the well at 61 feet, and the driller tried to get to depth with 60feet of auger and an extension. That worked, but when he pulled up the sand flowed in and blocked up the augers. The inspector was on his way (as I was assured by the driller he would be ready 2 hours after starting work), and ended up waiting half an hour before telling us we had been bumped to the end of the line and he would be back in two hours.
I could go on with things, but this is sufficient. Except for the traffic. Hooligan and I pulled off the site at 3:00. I had called 511 for traffic information, and found out that due to a police investigation, part of the Sunol Grade was closed, and it was already backed up from northern Fremont to Milpitas. So we decided to take 880 instead of 680. And of course, most everyone else was doing that, so it was slow. We had thought we would take 238 to 580 and then 13. But as we approached Hayward they announced that 238 south was closed do to an accident and 238 north was backed up with rubberneckers
We ended up taking two hours to get from Santa Clara to Pleasant Hill using Lawrence Expressway, 280 south, 880 north, 980 east, 24 east, and then Pleasant Hill Road to Taylor.
I am glad I am in the office for a week, and then on vacation.
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