The stages were sealed by rubber packing, tightened six volts and nuts, and applied by silicon sealant to prevent leakage of CH4. It was equipped with five sampling ports at the 7-, 25-, 50-, 75-, and 100-cm-depth from the top of the column
The stages were sealed by rubber packing, tightened six volts and nuts, and applied by silicon sealant to prevent leakage of CH4. It was equipped with five sampling ports at the 7-, 25-, 50-, 75-, and 100-cm-depth from the top of the column