Laserfiche WebLink
Thanks for the attachments with chloride data. I'll get it to my co-worker. <br /> -----Original Message----- <br /> From: John A Izbicki [mailto:jaizbick@usgs.gov] <br /> Sent: Monday, March 27, 2006 2:59 PM <br /> To: Mike Infurna [EH] <br /> Subject: Re: test test <br /> Hi MIke-- <br /> Good to speak with you Friday. Sorry I had to get off the phone I was in <br /> Sacto to meet with DWR about the proposed drilling at Atherton and Sandman <br /> Parks. Thanks for your thoughts. On the basis of what you said I plan to <br /> modify the well design to include: <br /> 1. 25 ft conductor casing. The conductor casing will be cemented in place <br /> and bentonite grout will be used to provide a surface seal for the wells <br /> inside the conductor casing. This should minimize you concern about grout <br /> desiccation above the water table. <br /> 2. The plan remains to use an 117/8 bit for the upper hole with 3, 2-inch <br /> diameter, PVC wells. I will ensure that the 117/8 bit is used to a depth <br /> greater than the shallowest well (about 200 ft) to allow sufficient <br /> borehole diameter to ensure a 2 inch spacing between wells. I will modify <br /> the well as-built schematic as you suggested to more clearly show spacing <br /> between the wells. <br /> 3. We will install multiple centralizers in the wells as you suggested near <br /> the upper and lower parts of each seal to ensure the wells are physically <br /> separate within the borehole. (I'll get you more info on our plans). The <br /> drillers will keep tension on the wells as the grout and backfill <br /> materials are installed to keep the well as straight as possible.This is <br /> our SOP to ensure that we can access the wells with our geophysical tools <br /> after construction. We will place the tremie pipe prior to well emplacement <br /> so that we are only pulling the tremmie upward and do not damage the <br /> 3 <br />