Injected Base Gas is the volume of gas that must be added to the Native Base Gas in order to bring the total volume of Total Base Gas to a sufficient level to maintain reservoir pressure.
The value is reported in MCF (thousand cubic feet of gas).
Follow this link to a more thorough discussion of < Terminology used to describe gas storage volumes >
U.S. Energy Information Administration, 2004, The basics of underground natural gas storage: U.S. Energy Information Administration Web site, http://www.eia.gov/pub/oil_gas/natural_gas/analysis_publications/storagebasics/storagebasics.html., date accessed, July 21, 2011.