The Contribution of Dust Particles from St. Lawrence Cement to Outdoor Dust in the Surrounding Waterfront-South Community in Camden, New Jersey: Research Project Summary

Abstract

In response to community concerns about dusty conditions in the Waterfront South area of Camden, NJ, and specific concerns that the nearby St. Lawrence/Holcim facility was a major contributor to these conditions, a study was undertaken to examine the contribution of that facility to dust deposition in the Waterfront South area. A composite sample of material was collected from the exposed piles at the facility and outdoor dust deposition and surface wipe samples were collected at multiple locations during two periods for a total of 52 days within a distance of 800 m of the facility as well as at a control location 2 km from the facility. Dust mass was examined as a function of distance from the facility, and the source material from the facility was compared to the community dust samples on the basis of elemental concentration (particularly calcium) and elemental ratios. In addition, a chemical mass-balance model was created that attempted to account for the elemental signature of the source material from the facility against the background of elemental occurrence in urban dust. Also, facility-wide deposition modeling was conducted using operations data supplied by the facility. Several independent lines of evidence point to a contribution from the facility of 2-13% with a most likely contribution in the range of 2-8% of the total dust material in the community at a distance of up to about 0.5 km. Unusual wind conditions could increase this contribution in the short-term. Both stack and fugitive emissions contribute to the facility’s overall dust emissions. However, fugitive emissions appear to be the larger source. This study was specifically focused on identifying the extant to which the St. Lawrence/Holcim facility contributed to the dust deposition in Waterfront South. It did not attempt to identify other contribution to the dust deposition. However, from other studies in the scientific literature in other locations, it appears that soil, and automotive use and wear (including tire wear) are major sources of urban dust.