It may seem counterintuitive for Robert F. Kennedy Jr., the eco-lawyer, to be peddling H20. But this week, he takes time out from hammering the mayor (for hedging on the city’s watershed agreement) to unveil a Newman’s Own-style brand of bottled water, tapped at Sweetwater Springs in Saratoga, New York. While spring water doesn’t have to meet the same FDA rules as city water supplies, the green Kennedy – as opposed to the cute Kennedy, or the embarrassing Kennedy(s) – says Keeper Springs Mountain Spring Water will be the first brand to meet those standards. “It is a political choice to drink bottled water,” he charges. “We felt this was the best place to educate the consumer that we can’t turn our backs on the public water supply.” So he’s selling the water in order to save it? “Yes,” he says. “It’s like diverting money from private schools back into the public schools. I drink New York City tap water.” The medium dilutes the message – but still goes down smooth