WSP12268

• File Number: 8509
• Description: San Luis Valley
• State: CO
• Basin: Rio Grande
• Water Division: 3
• Date: 6/1/1987
• Title: Interim Task 5 Report Deep Well Testing & field Investigation - San Luis Valley Confined Aquifer Study - Phase 1
• Water Supply Pro - Doc Type: Report/Study

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in the analysis because they were suspected to be non-representative
aquifer conditions due to casing storage effects in the well.

of

Transmissivity of HSU-2 at the Hooper Pool Well was calculated to be
approximately 9600 gpd/ft from a straight-line Jacob approximation analysis
(Driscoll, 1986) of the time-recovery data (Figure 2.3). From a residual-
drawdown graph of the recovery data (Figure 2.4) the transmissivity was
calculated to be approximately 11,000 gpd/ft (Appendix A).

The values of transmissivity (T) calculated from the recovery position of
the test are not expected to be as accurate as the T value calculated from the
flow pattern of the test, due to change in the flow rate over the flow period.
Such a change violates a required mathematical assumption of constant flow
rate prior to capping the well.

2.2.2 Carroll Well and Owens Well Testing
A flow test and a shut-in test were performed on the Carroll Well in
conjunction with the geophysical logging of that well. The flow test duration
was approximately 48 hours, beginning on August 27 and ending on August 29,
1986. The shut-in test followed the flow test, and was performed over a
period of approximately one hour on August 29, 1986.

During the flow test and shut-in test of the Carroll Well, head
(pressure) measurements were taken at the Owens Well, 1880 feet to the east-
southeast, to determine whether a head change could be detected over the flow
period. No formal flow tests or shut-in tests were performed on the Owens
well, because the well was in use to supply water to two swimming pools, a
shopping center, a convenience store, irrigation of several acres of lawn, an
RV park, one private residence, and a large mobile home park. Though
measurable head change in the Owens Well was expected over the 48-hour flow
period of the Carroll Well, none was observed with any confidence due to the
extreme "noise" of head fluctuations caused by rapid on-off cycling of flow to
many of the users of water from the Owens Well.

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