| MadSci Network: Chemistry |
Both trichloroethylene and tetrachloroethene (or perchloroethylene) are known to have health issues and are not recommended for use in areas with humans. In addition, tricholoroethylene can combust which makes it unsuitable for use in a confined space where ignition sources such as a boat engine or electrical wiring can ignite the vapors. Both are also volatile and will evaporate over time.
The solubility of low molecular weight organochlorine compounds in seawater was measured by Moore. In the case of trichloroethylene the solubility can be quite high depending upon the temperature. This would make the compounds unsuitable for use in a seawater environment.
The best solution would have been to isolate the lead from the aluminum when it was installed. If the lead is still accessible and can be removed, completely coating them with a two-part epoxy designed for use in a marine environment would be the best option. That will provide both a physical separation from the seawater and an insulator. You may also want to investigate attaching a sacrificial anode to the aluminum. Magnesium seems to be a viable candidate based upon the EMF table.
R. M. Moore (2000)
The solubility of a suite of low molecular weight organochlorine compounds in seawater and
implications for estimating the marine source of methyl chloride to the atmosphere
Chemosphere - Global Change Science 2(1):95-99.
doi:10.1016/S1465-9972(99)00045-8
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