← Basin groundwater

TUNNEY

Monitored well · 150639 · Division 1 · Water District 1

Its well permit here · Well permit at DWR ↗

Source DWR administrative record · verify at DWR well record ↗ Source DWR administrative record · verify at DWR permit record ↗

Unclassified

No aquifer or designated-basin assignment — administrative world unknown, kept out of recharge math.

Water-level record

No water-level measurements are cached for this well. It is in the well inventory — permit, construction and aquifer below — but nobody has logged a level we hold.

Geophysical log

DWR holds a geophysical log for this well, run 2016-01-11 (gamma, resistivity, spontaneous_potential). DWR's log page.

Formation picks (DWR)

AquiferTop ftBase ftNet sand ft
DENVER37 162
ARAPAHOE203 43

Net sand is DWR's own reading of the log (its gLogThickness), not the gross interval.

Net sand per aquifer, from the gamma curve

Computed here from DWR's own digital log (LAS): linear gamma index, clean/shale lines at p10/p90 of the gamma over the interval, sand where Vsh < 0.4, beds under 1.0 ft merged. DWR’s own pick is beside it, never averaged with it.

AquiferInterval ftNet sand ftNet / grossDWR net sand ftDifference ft
DENVER37–162 32 0.26

A gamma cutoff is a convention, not a measurement. Against DWR’s own picks on 50 wells this one correlates at r 0.86 with a median error near 30% and no bias (how it was scored).

Curves digitized from the scan

Hydrohistorian traced the scanned log automatically. 2 curves passed the confidence gate; 6 did not and are listed with the reason. Screening data: the scan stays the record.

CurveInterval ftCoverageVerdict Curves like this one scored
64" Normal Resistivity (Ohm-m) 2–440 7% not used: coverage 8%; ambiguous rows 39%; scale OCR confidence 0.68; curve class not verified by the benchmark: 64" Normal Resistivity traced as thin
64" Normal Resistivity (Ohm-m) 2–440 90% not used: ambiguous rows 83%
Natural Gamma (CPS) 2–440 96% pass r 0.99 median, error 3.3% of scale, 3% below r 0.8 (n 89) LAS
Single-Point Resistance (Ohms) 2–440 89% pass r 0.99 median, error 0.6% of scale, 6% below r 0.8 (n 49) LAS
Spontaneous Potential (mV) 2–440 90% not used: SP: the printed scale is a span with an unknown offset, and the benchmark could not verify the shape (median r 0.28 after offset removal)
Ohms (Ohms) 2–139 56% not used: ambiguous rows 16%; curve name not recognized: 'Ohms'
Ohms (Ohms) 140–343 43% not used: curve name not recognized: 'Ohms'
Ohms (Ohms) 360–441 59% not used: ambiguous rows 25%; curve name not recognized: 'Ohms'

"Curves like this one" is the benchmark row for this curve's class: curves of the same name traced the same way, scored against DWR's own digital log of the same run. r is correlation (the print's own smoothing allowed for); error is mean absolute error as a share of the track's printed range; "below r 0.8" is the share of passing curves in the class that still disagreed with DWR's log, which this curve's own numbers cannot rule out.

The LAS files and every verdict are in the statewide groundwater release (/data, table gw_digitized); the MCP server's gw_digitized_curves and gw_net_sand work from them. How well the tracer does was measured against DWR's own digital logs.

The well itself

Total depth420.0 ft
Ground elevation6020.0 ft
Permit79465
Location39.28000, -104.15000
What this page is not

Monitoring records are irregular: measurements cluster where somebody chose to look, so a trend describes this well's record, not the aquifer as a whole. Levels are DWR's published measurements, unedited. A trend here is not a prediction, and it is not a determination about anyone's water right.