from the Village of Marcellus. With the continuing northward retreat of the glacier, meltwater deepened the Nine Mile Creek Valley and cut the Camillus Valley that runs east from Martisco to the Village of Camillus. For a time this channel discharged to the east towards Syracuse at an elevation of about 500 feet. Eventually the glacier receded far enough north to open the channel near Rome New York that resulted in the formation of Glacial Lake Iroquois at an elevation of about 440 feet. Lake Iroquois had a relatively long existence, but 13,400 years ago the collapse of an ice dam led to the rapid draining of Lake Iroquois, and Nine Mile Creek started to assume its present form. Disappearing Lake The Disappearing Lake area in Pleasant valley area is a geologically significant feature of the area. This lake is located on an area of karst geology, which is typified by a cavernous underground landscape. Through the use of water tracer dyes, Proett (1978) identified a distinct hydrologic connection between Disappearing Lake and its eventual outlet into Nine Mile Creek at Marcellus Falls. Although Disappearing Lake is a springtime phenomenon, groundwater outlets at Marcellus Falls have been observed to be active as late as October. These groundwater flows serve as a significant input of cold, nutrient-rich waters during summer months. It is notable that water flowing through karst systems is sensitive to change. This is because water flows too quickly through such cavernous networks to allow pollutants to be removed from the system. In particular, White noted that nitrates are not broken down as they flow through karst drainages. Thus nitrate inputs into the groundwater system at Pleasant Valley may be expected to be similar to the outputs into Nine Mile Creek at Marcellus Falls. From this perspective, sources of road salt, agricultural runoff, and E. Coli are all concerns for upland areas associated with Disappearing Lake area. This is because they may eventually alter water quality in Nine Mile Creek below Marcellus Falls. A similar phenomenon occurs in the watershed of Geddes Brook, the largest tributary of Ninemile Creek. The headwaters of Geddes Brook disappear into channels in the limestone at Lost Lake, at the top of the Onondaga escarpment. The stream reappears at the foot of the escarpment as a series of springs. Soils The predominant soil types associated with the Nine Mile Creek corridor are Teel and