422 The UMAP Journal 22. 4 (2001) teams of students that are focused for four days on"solving" a complex prob lem. The breadth of approaches that were used by the teams this year was truly Impressive. Basis for Contest Question: Queen of the American Lakes, Lake George, NY Until recently, it was thought that zebra mussels had not invaded Lake George, New York, the home of the Darrin Fresh Water Institute DFWD) Since 1995, the DFWI had carried out a zebra mussel monitoring program in Lake George where zebra mussel larvae had been observed in only two of the years In 1997, larval zebra mussel numbers at 1 of 11 locations were comparable to those observed in the Hudson River, an area of high zebra mussel colonization Despite the presence of larvae, no adult zebra mussels or settled juveniles had been observed. In December of 1999, the situation changed when two divers from the Bateaux Below Inc, a nonprofit organization dedicated to underwater archaeology, found adult zebra mussels at the southern end of lake george In response to the discovery of these mussels, the dFWI has been working intensively at the site to determine why adult zebra mussels were able to survive and reproduce, ways in which they could have been introduced to this location and an appropriate action to eradicate them from this location The discovery of zebra mussels in Lake George was particularly surpris ing given the low calcium content and low pH of the lake; laboratory tank experiments had previously shown that zebra mussel larvae would not sur vive under these conditions. However, water chemistry analyses conducted at the site where the mussels were found revealed calcium and ph levels higher than that characteristic of the majority of Lake George. Further investigation revealed that water entering the lake from a nearby culvert was introducing stormwater runoff and groundwater into the lake with calcium levels four times higher than that characteristic of the rest of the lake. In addition, the site contains numerous concrete and rock aggregates that are likely sources of additional calcium. Finally, there is potential contribution of calcium from a concrete boardwalk that was built approximately a year before the discovery of zebra mussels at this location troduction of zebra mussels may have occurred when boats contaminated from other lakes entered Lake george at the boat launch adjacent to the site Introduction could also have occurred during the construction of the nearby boardwalk via contaminated equipment. The exact mechanism(s) by which they were introduced may never be known After discovering zebra mussels in Lake George, the dFWI and Bateaux Be low scuba divers carried out an extensive survey of the location to determine the size of the affected area. The mussels were confined to a 15, 000 square foot area. After consultation with state and local agencies, it was agreed that422 The UMAP Journal 22.4 (2001) teams of students that are focused for four days on “solving” a complex prob￾lem. The breadth of approaches that were used by the teams this year was truly impressive. Basis for Contest Question: Queen of the American Lakes, Lake George, NY Until recently, it was thought that zebra mussels had not invaded Lake George, New York, the home of the Darrin Fresh Water Institute (DFWI). Since 1995, the DFWI had carried out a zebra mussel monitoring program in Lake George where zebra mussel larvae had been observed in only two of the years. In 1997, larval zebra mussel numbers at 1 of 11 locations were comparable to those observed in the Hudson River, an area of high zebra mussel colonization. Despite the presence of larvae, no adult zebra mussels or settled juveniles had been observed. In December of 1999, the situation changed when two divers from the Bateaux Below Inc., a nonprofit organization dedicated to underwater archaeology, found adult zebra mussels at the southern end of Lake George. In response to the discovery of these mussels, the DFWI has been working intensively at the site to determine why adult zebra mussels were able to survive and reproduce, ways in which they could have been introduced to this location, and an appropriate action to eradicate them from this location. The discovery of zebra mussels in Lake George was particularly surpris￾ing given the low calcium content and low pH of the lake; laboratory tank experiments had previously shown that zebra mussel larvae would not sur￾vive under these conditions. However, water chemistry analyses conducted at the site where the mussels were found revealed calcium and pH levels higher than that characteristic of the majority of Lake George. Further investigation revealed that water entering the lake from a nearby culvert was introducing stormwater runoff and groundwater into the lake with calcium levels four times higher than that characteristic of the rest of the lake. In addition, the site contains numerous concrete and rock aggregates that are likely sources of additional calcium. Finally, there is potential contribution of calcium from a concrete boardwalk that was built approximately a year before the discovery of zebra mussels at this location. Introduction of zebra mussels may have occurred when boats contaminated from other lakes entered Lake George at the boat launch adjacent to the site. Introduction could also have occurred during the construction of the nearby boardwalk via contaminated equipment. The exact mechanism(s) by which they were introduced may never be known. After discovering zebra mussels in Lake George, the DFWI and Bateaux Be￾low SCUBA divers carried out an extensive survey of the location to determine the size of the affected area. The mussels were confined to a 15,000 square￾foot area. After consultation with state and local agencies, it was agreed that