CRITICAL AND POTENTIALLY TOXIC METALS IN SOILS FROM THE SHAWANGUNK ORE DISTRICT, NEW YORK

Critical metals in the US are very important for modern technology and industry. The former small historic mining operations in the Shawangunk Mountains in New York produced tailing piles of waste rock and low-grade ore that have the potential to contribute to a renewed source of critical minerals in the US. However, the associated heavy metals from the former mining activities may produce potential contamination of the surrounding soils containing high concentrations of toxic metals. This project aims to discover if the smaller tailing piles, pits, and other mining features are deleteriously affecting the environment with potentially toxic metals like lead, mercury and cadmium while also looking to see if the soil could be examined as a proxy for critical minerals such as zinc, gallium, silver and others.

Limited research has been conducted in proximity to the former mining operations at the Wurtsboro Mine, which is a Superfund site due to high levels of lead in sediment downgradient of the mine and the state is still in the process of conducting a remediation plan. However, no studies have been completed on the potential contamination affiliated with any of the smaller historic mines.

The main soil units underlying the study area are: Arnot-Lordstown complex (ANC), Arnot-Lordstown complex (AND), and Swartswood and Mardin soils, (SXC). ANC soils are channery silt loam to very channery silt loam, varying brown to tan. AND soils are moderately decomposed plant material, channery silt loam, and very channery silt loam, dark brown, brown to tan soils. SXC soils are gravelly loam to a gravelly fine sandy loam, varying brown to tan.

Eleven soil samples were collected downgradient from several of the historic former lead and zinc mines of the Shawangunk Mountains, NY in late summer 2024 and sent to ALS Global for a total metal analysis. The soil testing for metals involved acid digestion and analysis using inductively coupled plasma – mass spectrometry (ICP-MS). The soil samples were compared to bulk rock geochemistry from the tailings piles to discover if there is any level of concentration or dilution in the soils versus the waste/low grade rocks, to determine if the metals have mobilized from the former mining activities and to hopefully rule out potential environmental risk to the surrounding community.