CHECKING FOR ATMOSPHERIC DEPOSITION NEAR EAST BRANCH FISHING CREEK, SULLIVAN COUNTY, PA

East Branch Fishing Creek lies in southern Sullivan County, PA, in the headwaters of the nearly 400 square mile Fishing Creek Watershed. This part of the watershed, designated a high quality cold water fishery, is listed as impaired by pH and metals from atmospheric deposition. Because snow can effectively capture atmospheric dust and act as a reservoir of contamination, surface and composite snow samples and some stream water samples were collected in the headwaters of Fishing Creek in February 2021 to better constrain both the possible impact of snow to metals in the headwaters, and the seasonal variations in metal concentrations in the Creek. Samples of snow and water from adjacent streams were collected from vehicle-accessible locations in the headwaters of Fishing Creek. For comparison, additional snow samples were collected from two locations along I80 presumed to be more heavily impacted by anthropogenic activities. Both filtered and non-filtered snow samples were analyzed for selected metals via ICP-OES. Dissolved oxygen, temperature, pH, and conductivity were measured in situ at stream water sample collection sites. In the lab, stream samples were analyzed for metals and common anions. A portable XRF was used to analyze particles caught on filters. Metals (Al, Ba, Cd, Mn, and Zn) were detected at concentrations of 1-60 ppb in stream samples. Cadmium was detected in non-filtered stream samples at concentrations around 28 ppb, more than 5 times the primary MCL of 5 ppb. It was not detected in filtered stream samples or in snow samples. Aluminum (5 to 50 ppb) and barium (50 to 150 ppb) were detected in most snow samples, including those collected near I80. Arsenic was detected in snow samples from all locations at concentrations of around 250 ppb, far greater than the MCL of 10 ppb, but was not detected in stream samples. Our analysis indicates that although falling snow did collect some metals over the winter 2020-21 season, it was unlikely that it contributed substantial amounts of metal to the headwaters of Fishing Creek.