FIG. 1.

Detailed map of the field study site within the Carson City Park, Carson City, MI. The positions of the VRPs at the contaminated (5) and background (9) locations are noted. Samples for microbial analysis were collected at the same locations, adjacent to the VRPs. To the north of the sampling site is the former petroleum refinery where the leaking underground storage tanks were located. The thicknesses (in meters) of the free-phase LNAPLs over the study area are given, as well as the boundary of residual LNAPL contamination. The location of a drainage ditch running through the site is also shown.