This project will generate fundamental and applied research in these key areas.
1. The chemical-physical properties of 4-methyl-cyclohexane methanol (MCHM) have not all been evaluated and they are necessary to determine the fate and transport within the drinking water treatment, distribution system (for example, consumers homes), and natural waters. The first stage of this research will be to quantify the chemical properties of MCHM. Specifically: the octanol-water partition coefficient (Kow) will be generated using C18 HPLC retention time; the aqueous solubility (S) will be measured by saturating water with MCHM and measuring the aqueous concentration; and the Henry's Law constant (H) will be measured using static headspace equilibrium and SPME-GC/MS. 2. Previous work by the researchers has developed a predictive model of diffusion coefficients and solubility for a wide range of organics in plastic pipe. Using Kow and S values, diffusion and pipe solubility's will be estimated. This will help validate laboratory results from other research also investigating the MCHM spill. 3. MCHM has a low aqueous odor threshold of approximately 0.00001 mg/L. Thus consumers can potentially become important monitoring sentinels for exposure to low levels of MCHM. The main location in the house to detect off-odors is the shower because of high water temperatures and water flows in a confined area. Using previous modeling work by the researchers and the measured Henry's Law constants from stage 1 above, dynamic models of MCHM air concentrations for typical showering conditions will be developed. This will confirm if consumer sensory detection can aid in detecting locations of residual MCHM. It will also aid in the utility's understanding of consumer complaints, and in the longer term will aid in exposure assessment through inhalation. 4. While polyethylene pipe materials have been shown to interact with organic chemicals, less is known about the interaction of organics with epoxy materials used to line water pipes and storage tanks. Drinking-water-grade epoxy-liner will be used to evaluate sorption/uptake performance for MCHM. Diffusion coefficients and solubility in epoxy will be determined using weight gain/immersion, time lag, and diffusion/ permeation methods. Similar experiments will be conducted on polyethylene pipe materials.
On January 10, 2014, residents of nine West Virginia counties were told by their governor "Do Not Drink the Water" because it was contaminated with odorous 4-methyl-cyclohexane methanol (MCHM) which is used to clean coal. Even though the water restrictions began to be lifted on January 13, 2014 and all residents are eventually expected to be able to drink tap water, there are still many scientific knowledge gaps in the short and long term fate and transport of this chemical in water systems. This RAPID Grant will address many of those gaps. This research seeks to provide fundamental scientific data that can be used to avoid potential health and environmental problems caused by the MCHM spill in West Virginia and the subsequent contamination of the drinking water treatment and distribution system. The knowledge gained will be shared with the scientific and engineering communities through journal publications and presentations at professional conferences. The knowledge on pipe material contamination and decontamination will be shared with the general public through a short, citizen-oriented publication to be posted on the Water Resources Research Center web page. Student researchers will disseminate the knowledge gain through blogs on our "Water INTERFACE Interdisciplinary Research" website.
