← Basin groundwater

PRI #2

Monitored well · 152126 · Division 1 · Water District 8

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 2017-11-07 (gamma, resistivity, spontaneous_potential). DWR's log page.

Formation picks (DWR)

AquiferTop ftBase ftNet sand ft
DENVER1140 1948
ARAPAHOE2004 2520
DAWSON 1038

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
DENVER1140–1948 376 0.47
ARAPAHOE2004–2520 335 0.65

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. 1 curve passed the confidence gate; 15 did not and are listed with the reason. Screening data: the scan stays the record.

CurveInterval ftCoverageVerdict Curves like this one scored
16" Normal Resistivity (mV Ohm-m) 50–2555 99% not used: ambiguous rows 99%
Natural Gamma (CPS) 50–2555 93% not used: curve class not verified by the benchmark: Natural Gamma traced as thin
Single-Point Resistance (ohm) 50–2555 96% pass r 0.99 median, error 0.6% of scale, 6% below r 0.8 (n 49) LAS
ohm (ohm) 20–179 13% not used: coverage 13%; curve name not recognized: 'ohm'
ohm (ohm) 200–399 10% not used: coverage 10%; curve name not recognized: 'ohm'
ohm (ohm) 420–619 11% not used: coverage 11%; curve name not recognized: 'ohm'
ohm (ohm) 640–839 1% not used: coverage 2%; curve name not recognized: 'ohm'
ohm (ohm) 860–1059 10% not used: coverage 10%; curve name not recognized: 'ohm'
ohm (ohm) 1080–1279 7% not used: coverage 7%; curve name not recognized: 'ohm'
ohm (ohm) 1300–1499 6% not used: coverage 6%; curve name not recognized: 'ohm'
ohm (ohm) 1520–1719 11% not used: coverage 11%; curve name not recognized: 'ohm'
ohm (ohm) 1740–1939 12% not used: coverage 12%; curve name not recognized: 'ohm'
ohm (ohm) 1960–2159 10% not used: coverage 10%; curve name not recognized: 'ohm'
ohm (ohm) 2180–2379 15% not used: coverage 15%; curve name not recognized: 'ohm'
ohm (ohm) 2400–2558 20% not used: coverage 21%; ambiguous rows 47%; curve name not recognized: 'ohm'
ohm (ohm) 2398–2540 18% not used: coverage 18%; ambiguous rows 55%; curve name not recognized: 'ohm'

"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 depth2555.0 ft
Perforated interval2210.0–2520.0 ft
Ground elevation7600.0 ft
Permit81145
Location39.05000, -104.72000
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.