Analytical Results and Findings: Little Galloo Island

Published February 1, 2000

Soil/Guano

By far the most interesting and alarming discoveries of the Chopra-Lee Inc. investigation involve the soil and soil/guano samples obtained from Little Galloo and Galloo Islands.

Analytical evaluation of the samples shows elevated levels of PCBs, mercury, and DDE in all four soil/guano samples obtained from Little Galloo Island. The soil samples from neighboring Galloo Island, which was used as a background-testing site, showed no trace of PCBs or the pesticide DDE. Some mercury was found in the soils from Galloo Island.

The PCB level of 4.78 mg/kg (ppm) for the guano/soil sample “S-2 top,” obtained from beneath a dead tree trunk on the northeast side of Little Galloo Island, exceeds the recommended cleanup level for surface PCBs. Elevated levels of PCBs and DDE were found in all the remaining soil/guano sampled from Little Galloo Island but were within the recommended cleanup levels. The mercury readings from sample locations “S-2 top” and “S-2 bottom” exceeded the cleanup objective level established by the New York State Department of Environmental Conservation.

Surface Water

The surface water samples obtained from the Little Galloo and Galloo island areas (W-1 – W-8) showed a pattern of contamination differing in the upwind and downwind locations.

The total bacteria samples from the two near-shore and two off-shore sampling sites of Little Galloo Island showed expected results. Sample location W-4, approximately 500 yards from the southwest shore (upwind) of Little Galloo Island, had a total bacteria count of less than 33. The other three sites from the Little Galloo Island area showed high total bacteria counts from the near-shore (14,600 and 10,133) and downwind off-shore (1,367) sampling sites.

A pool of standing water on the northwestern side of Little Galloo Island (sample W-3) showed an extremely high total bacteria count of 43,700 colony-forming units.

Private Wells on Henderson Bay

The two residential groundwater wells sampled and analyzed as part of the Chopra-Lee Inc. investigation showed interesting and contrasting analytical results. No pesticides or PCBs were found in the groundwater from either location. The total bacterial count of the groundwater at the residential house on Henderson Bay (W-10) had an elevated level of colony-forming units (12,767) compared to the Jenkins residential house (W-9) where only 1,000 colony-forming units were found. The 12,767 colony-forming units are similar in number to the quantities found near Little Galloo Island. Additionally, elevated levels of nitrates, aluminum, calcium, iron, potassium, and zinc were found in the groundwater sample from W-10 as compared to sample site W-9. Some of the results were over 10 times higher in comparison.

Source: Great Lakes Basin Report.