HomeMy WebLinkAbout10 Aqua Hydrogeologic Consulting r-;�--TRUCKE�E DONNER
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Memorandum
To: Board of Directors
From: Ed Taylor, Water Superintendent
Date: 211l2002
Subject: Consideration of proposal from Aqua Hydrogeologic Consulting to provide
hydrogeologic services in the rehabilitation of the sand problem in the Martis
Valley Well.
BACKGROUND.
In the spring of 2001, the District drilled and put into service a new well know as the Martis
Valley Well The well produced good quality water until November of 2001. At which time the
well started to produce sand. The District needs the water production from this well. Staff is
proposing to rehabilitate the well with the guidance of David Carlson of Aqua Hydrogeologic
Consulting.
Staff recommends that a contract be approved in the amount not to exceed of$25,619 with
Aqua Hydrogeologic Consulting for hydrogeologic services for the rehabilitation of the Mards
Valley Well sand problem per the attached proposal.
RECOMMENDATION:
I recommend that the Board approve the proposal from Aqua Hydrogeologic Consulting for
hydrogeologic services in the amount not to exceed of$25,619 for work to rehabilitate the
sand problem at the new Martis Valley Well and authorize the execution of an agreement for
the proposed services.
Attached:Aqua Hydrogeologic Consulting Proposal
0 Page 1
HydrogeologiC Consulting
January 23, 2002
Mr. Ed Taylor
Water Superintendent
Truckee Donner Public Utility District
11570 Donner Pass Road
Truckee, CA 96160
RE: Hydrogeologic Consulting Services for rehabilitation supervision and testing of the Mattis
Production Well
Dear Ed:
As a follow-on to our meeting of Friday, January 11, 2002, I have prepared the following scope of
work and cost estimate for the providing hydrogeologic consulting services for rehabilitation and testing
the Mattis Production Well. The following summarizes the proposed work plan, a detailed scope of
work and cost estimate follows the summary.
• Review the existing well report and develop a rehabilitation program for determining where the
silt is coming into the well.
• Provide on-site supervision and data collection during the rehabilitation program and provide
on-site supervision and conduct field measurements during the water quality sampling program.
• Provide on-site supervision during the swedging of blank casing to prevent silt and possibility
arsenic from coming into the well.
• Supervise and collect data during the pump development and pumping test program
• Prepare report summarizing all activity containing findings and recommendations.
The above is a brief summary of the activity to be covered under this proposed scope of work. The
following is a more detail summary of each proposed tasks and a cost estimate to perform the
described work.
Scope of Work
Task 1 Report Review with Rehabilitation Recommendation Review the Nimbus report for
both the Martis exploration and production well. During this review a comparison between
collected silt sample and the geologic log will be made. Early review of the information
provided indicates that the silt is coming into the well through a screen section opposite a
clay and silt zone located at a depth of 322-335 feet below ground surface. During this
task a site visit will be conducted to measure the gravel level using the gravel fill pipe. If the
gravel pack level has fallen below a depth of 322 feet, this would expose the screen
openings directly to the formation clay and silt layers.
P.O. Box 18793 a Reno Nevada 89511 a (775)250-9700 a Fax (775)841-0946 a DavidECarlson@msn.com
Task 2 Well Rehabilitation and Sampling During the initial phase of this task, a video survey of
the well interior will be completed to total depth. This is undertaken to ensure the integrity
of the well casing. It is possible, however unlikely that the casing developed a break which
may have allowed the sand and silt to enter into the wellbore through the casing break.
Through the use of the video, the integrity of the casing can be verified before moving onto
the actual well rehabilitation phase.
After the video survey is completed AquA personnel will work with Carson Pump
personnel to develop a program which will enable discrete sampling throughout the
wellbore by using a 10 foot swab. Through the use of the swab and pumping
approximately 300 gpm from each selected section, the section which is contributing silt into
the wellbore will be identified. The swab will also be used to collect water quality samples
to total depth at possibly 40 or 60 foot intervals. Field parameters (temperature, pH, and
EC) of each water sample collected will be performed. The water samples will be
submitted to a certified lab to be tested for arsenic.
Task 3 New Casing Installation This task will involve providing on-site supervision during the
swedging of blank casing to the screen section which is contributing silt into the wellbore.
In addition, if it is determined through water quality analysis that the arsenic is coming into
the well through a screen section that can be blanked off, a blank casing section will be
swedged into place to minimize the arsenic from corning into the wellbore.
Task 4 Well Development and Testing This task will involve providing on-site supervision and
outlining the pump development and pumping test program which will be conducted after
the completion of Task 3. It is anticipated that the pump development program will be
completed within one or two days. After the pump development is completed, a constant-
discharge test will be conducted. If sufficient data is collected during pump development a
step-test drawdown test may not be required to be performed prior to the constant test.
The constant-discharge test will be performed for a minimum two or three days, after which
recovery water level readings will be recorded. The pumping test is required to determine
the long-term production yield effects of the well after placing blank casing in the wellbore
opposite the silt and possibility arsenic producing zones.
Task 5 Reporting This task will summarize in a report all of the activity that was completed in
Tasks 1 through 4. In addition this report will contain water quality results from laboratory
analysis. Results of the pumping test with data analysis will also be presented in the report.
Finally the report will contain a recommendation with regard to long-term production yield
potential.
Cost Estimate
Task 1 Report Review with Rehabilitation Recommendation
Senior Hydrogeologist 16 hrs @ $85/hr 1 360
Total S1,360
Task 2 Well Rehabilitation and Sampling
Senior Hydrogeologist 12 hrs @ $85/hr $1,020
Geologist 52 hrs @$65/hr 3,380
Per diem(lodging and mileage) 4 days @ $115/day 460
Total $4,860
Task 3 New Casing Installation
Senior Hydrogeologist 8 hrs @ $85/hr $ 680
Geologist 26 hrs @ $65/hr 1,690
Per diem 2 days @ $115/day 230
Total $2,600
Task 4 Well Development and Testing
Senior Hydrogeologist 24 hrs @ $85/hr $2,040
Geologist 84 hrs @$65/hr 5,460
Field Technician 28 hrs @$55/hr 1,540
Per diem 10 days @ $115/day 1,150
Total $10,190
Task 5 Report
Senior Hydrogeologist 40 hrs @ $85/hr $3,400
Graphics Designer 16 hrs @ $65/hr 880
Total $4,280
Sub-Total $23,290
Contingency 10% $2,329
Project Total S25,619
During the sampling and 24-hour pumping/recovery phase of the rehabilitation, a per diem allowance
has been included in the cost estimate. This will allow the crew to stay in Truckee rather than drive
back to Nevada after pulling their shift. Mileage costs have been included where appropriate.
s « J
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I have already contacted Dan Trampe at Carson Pump, and he is scheduled to start the work during
the first week in February. It is anticipated that the entire well rehabilitation and retesting program can
be completed in approximately two weeks.
If you have any questions regarding this letter, the scope of work, or cost estimate please contact me at
(775) 250-9700.
Sincerely,
QavV'/L
David Carlson