DDW-2024-009694

J. Paul Wright <[e-mail]>
Johnson Canyon Well #4 (WS006) File #15254 - Review Comments
Brent Gardner <[e-mail]>Tue, Jul 30, 2024 at 3:14 PM
To: "J. Paul Wright" <[e-mail]>
Cc: Glen Carnahan <[e-mail]>, "Dale Gardner ([e-mail])"
<[e-mail]>, Mike Noel <[e-mail]>
Mike Noel called and I thought Glen had taken care of this but not sure if you have seen a response. I still need to speak
to Mike Noel as PVC screen is also less efficient in allowing water through the screen which creates more head for
pumping but the attached is for PVC Casing and Screen.

Attached are the red lines that I believe address the specifications and a clean copy is also provided. My responses to
each of the questions are below:

Brent E. Gardner, PE
[e-mail]
43 South 100 East, Suite 100 • St George, Utah 84770
T: 435.628.6500 • F: 435.628.6553 • alphaengineering.com

From: J. Paul Wright <[e-mail]>
Sent: Thursday, July 11, 2024 4:24 PM
To: Glen Carnahan <[e-mail]>; Brent Gardner <[e-mail]>
Cc: [e-mail]; Kane County Water Conservancy District <[e-mail]>; Mike Noel
<[e-mail]>
Subject: Johnson Canyon Well #4 (WS006) File #15254 - Review Comments

Glen and Brent,

I have reviewed the drilling plans for the Kane County WCD - Johnson Canyon (13038), Johnson Canyon Well #4 drilling
project and I have some questions/comments.

1) The bid schedule (Section 107, Bid Item 1.2) shows that a 20" borehole and 20" casing will be installed. I have a
couple of questions and some corrections needed:
The borehole needs to be at least 4 inches larger in diameter to accomodate a proper grout seal. The drawing
calls out at least a 2-inch annular space, but does not specify the minimum borehole diameter. The bid schedule
should be corrected to reflect this. Changed to a 26” diameter hole being drilled for the top 100 feet with a 22”
0.312 wall steel carrier casing being installed.
The 20-inch conductor casing type (steel I assume) and thickness have not been specified, this needs to be
clarified. Clarified above.
7/30/24, 3:22 PM State of Utah Mail - Johnson Canyon Well #4 (WS006) File #15254 - Review Comments
https://mail.google.com/mail/u/0/?ik=f3bcb897f8&view=pt&search=all&permmsgid=msg-f:1806040157085995790&simpl=msg-f:1806040157085995790 1/2
2) The bid schedule (Section 107, Bid Item 1.4) shows that a 20" borehole will be drilled to the bottom of the hole,
however the drawing shows the borehole being slightly smaller than 20 inches. Obviously, once the conductor casing
(20-inch) is installed, it needs to sit on that shelf, the borehole to the bottom should be smaller than 20 inches in diameter.
This should be corrected. Corrected above.

3) The well detail at the end of the specifications calls out PVC SDR 17, 12-inch casing and PVC SDR 17, 12-inch slotted
well screen. But Bid Item 1.7 calls out the PVC SDR 17 slotted screen and stainless steel spacers, so this discrepancy
needs to be resolved. Specification modified to include only PVC SDR 17 screen and casing.

4) From what I can tell, you are planning a 12-inch steel casing for the top 300 feet of the well and the PVC well casing
below that to a depth of 600 feet. In looking online, it appears that PVC SDR 17, 12-inch well casing should only be
installed to a maximum depth of 450 feet (see table below). You will need to provide proof that this casing can be used at
these depths. Also, I need you to verify that the PVC being used is marked "Well Casing " and meets ASTM 480-14
according to R655-4. Attached is the Johnson Screen information for the well screen and casing. The tensile strength of
the screen is listed at 36,200 lbs. The weight of the screen is 18.89 lbs/ft which is less than the well casing pipe. If we use
the casing weight of 19.18 lbs the total hanging weight for 600 feet is 11,508 lbs so there should not be an issue with
depth as far as weight of screen and casing as the total allowable is 36,200 lbs. I verified this with Johnson Screen.
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3 attachments
Flush-Thread-PVC-Wells-Screens-Casings-Accessories.pdf
3035K
Johnson Canyon Well #4 Drilling Specification BG Red Lines (002).pdf
526K
Johnson Canyon Well #4 Drilling Specification without Red Lines (002).pdf
526K
7/30/24, 3:22 PM State of Utah Mail - Johnson Canyon Well #4 (WS006) File #15254 - Review Comments
https://mail.google.com/mail/u/0/?ik=f3bcb897f8&view=pt&search=all&permmsgid=msg-f:1806040157085995790&simpl=msg-f:1806040157085995790 2/2