sentences:  The bottom of the pond is made up of fine silt and clay muds with large cobbles, clasts and boulders in some places left behind by the retreat of the glaciers.In a study conducted by University of Massachusetts-Amherst in 2013 and again in 2014, X-ray fluorescence data shows slightly higher abundance of lead and zinc within the upper 50 centimeters of sediment cores taken out of the pond.These elements are common in the shallowest sediments of many ponds throughout the Northeast US, left behind by industrial pollution and leaded gas emissions.