Raw and temperature corrected hydrogen (cH₂) concentration trace during the initial gas extraction at the AXH13 site near DMP Harvey-2, corresponding to the peak shown in Figure 4h and inset. The hydrogen signal increases continuously and reaches a maximum after 26 seconds of pumping (~120 cc of gas extracted), consistent with elevated concentrations sourced from the perforated chamber of the downhole probe assembly (80 cm to 1 m depth).