Everyone performs step-drawdown tests but few people know how
to analyze the data. Analyzing step-drawdown tests requires the use of complex graphical
techniques which are not widely taught. StepMaster uses graphical analysis methods to
analyze step-drawdown tests quickly and reliably. No other program is designed
specifically for Step-Drawdown like StepMaster.

Graphical Test Analysis Methods

Eden-Hazel (step-drawdown and recovery to
estimate aquifer transmissivity linear well loss coefficients)

Birsoy-Summers (step-drawdown and recovery
analysis to estimate aquifer transmissivity and storativity)

Hantush-Bierschenk (to estimate linear and
non-linear well loss coefficients)

StepMaster Features

Accepts up to twelve pumping rates (it is not necessary for
rates to be consecutively increasing or of the same duration)

Write tab delimited tables of special values Eden- Hazel's H
and Birsoy-Summers adjusted time. This allows further independent analysis.

All calculations are displayed in moveable, customizable text
boxes.

Arithmetic, Semi-Log, and Log-Log graphs

Extensive ability to eliminate unwanted data or entire steps
from the analysis

StepMaster Example Screens Click on an image to view full size

The Eden-Hazel method is a two-part graphical analysis. The
method provides estimates of aquifer transmissivity and an equation describing well
drawdown with pumping rate as the independent variable. (15332 bytes)

The Birsoy-Summers is a graphical method to provide estimates of
aquifer transmissivity and storativity. (17720 bytes)

Shown here is the Clark (1978) data set, in the first graph of the
Hantush-Bierschenk analysis. The Hantush-Bierschenk method does not provide T or S, but
does provide well loss coefficients and an equation describing well drawdown with pumping
rate as the independent variable. (15531 bytes)

Shown here is the Eden-Hazel method with the Calliope example data set
published with the original Eden-Hazel paper. The Eden-Hazel method works with
increasing or decreasing discharge rates as well as recovery data. (16216 bytes)

Show here is an arithmetic time-drawdown graph where the initial step
was pumped at a higher rate than subsequent steps. Even this data can provide
reliable estimates of aquifer transmissivity with StepMaster. (15902 bytes)

Shown here is the above data analyzed with the Eden-Hazel method.
(18502 bytes)

The Eden-Hazel method also provides transmissivity estimates for a
simple constant rate pump test with recovery data, as shown here with an example data set
from Todd (1980) (16505 bytes)

Show here is a semi-logarithmic graph of the above recovery data.
(14714 bytes)