Figure 5.
The graph shows cumulative flow plotted against time in days for inflow and outflow under 32 kilo pascal and 55 kilo pascal gradients. At 32 kilo pascal, inflow decreases from 0 to about minus 1.4 millilitres while outflow increases from 0 to about 1.3 millilitres over about 1.1 days. At 55 kilo pascal, inflow decreases from 0 to about minus 1.5 millilitres while outflow increases from 0 to about 1.4 millilitres over about 0.65 days, showing higher gradient leading to faster change.Typical cumulative inflow and outflow data during a multi-step hydraulic test, in this case on sample SM1. Inflow and outflow are proportional to the hydraulic gradient