The high-pressure Ar gas TPC (HPgTPC) Option for the DUNE Near Detector is a fine-grained tracker with an active volume approximately 5 m in diameter by 5 m long. This cylindrical geometry is a copy of the ALICE TPC and it is assumed that we will re-purpose the ALICE readout chambers, which will become available in 2019. Two new readout chambers will have to be built, however, to fill the central barrel region. Assuming 10 Atm operation, the total active mass of the detector is 1.8 t with a fiducial mass of 1 t. This fiducial mass produces 1.6X10^6 CC nu_mu events per year of exposure. In this report, we will describe how this fined-grained tracker functions as part of the near detector suite of instrumentation and will answer specific questions raised by the ND conveners.