ELUCIDATION OF BROWN STAINS IN WELLNESS CENTER POOLS

The Sentara RMH Wellness Center (Harrisonburg, VA) is experiencing the formation of persistent brown stains on the plaster bottoms and walls of the saltwater swimming pools. Staff has previously removed the stain by scrubbing with muriatic acid. However, even with the re-plastering of the pools, the stain has returned. The goals of this project are to identify the chemical constituents of the stain, the source(s) of origin and to recommend possible mitigative strategies. The chemical components of the water and stains were evaluated with a variety of methods, including commercial stain identification products, Inductively-Coupled Plasma Mass Spectrometry (ICP-MS) and Scanning Electron Microscopy - Energy Dispersive Spectroscopy (SEM-EDS). The composition of the stain was determined to be a combination of copper and iron. The source of origin is thought to be corrosion of heaters and associated plumbing. Low pH and calcium hardness are contributors to corrosion, pitting, and stain formation.

Additional Abstract Information

Student(s): Madison Roberts

Department: Chemistry and Biochemistry

Faculty Advisor: Dr. Daniel Downey

Type: Oral

Year: 2019