[5717] in Central_America
Re: New quotes for Tue Nov 29
jcb@ATHENA.MIT.EDU (jcb@ATHENA.MIT.EDU)
Thu Dec 29 11:07:18 1994
I don't know about the classifications, but there are times especially
during the summer when Cambridge water is classified as hazardous waste
and legally must be neutralized before disposing of it down the drain.
One criterion for classifying a material as hazardous waste is having a
pH less than 5 or greater than 10. It is illegal to drain dispose these
materials without neutralizing them. However, many old buildings in
Cambridge still have lead pipes. At high pH values, the lead forms lead
hydroxide, which is insoluble in water. (These are the little lead
balls you may find stuck behind the screens on your faucets.) Since the
city officials have decided that having the water be too alkaline is
less dangerous than allowing the lead to remain in solution where it can
be ingested, they raise the pH of the water. In the summer (since
solubility goes up with temperature), the pH of the water gets as high
as 10.5, which results in the water being classified as hazardous waste.
