You forgot to include the link. Is it COEJL, the Coalition on the Environment
in Jewish Life? If not, I would like very much to find out about it.

Don't know if this is mainstream Judaism,

Not sure if you would call it mainstream Judaism, since it cuts across
denominational lines. Offhand, I would say that the Reform and
Reconstructionist movements (least traditional) are the most active in
environmental concerns, with Orthodox the least & Conservative in the middle.
The State & people of Israel do not have a very good record so far on
conservation & ecology, but the Jewish National Fund and the Society for the
Preservation of Nature in Israel occasionally manage to make themselve heard.
Iris,
Central NY, Zone 5a, Sunset Zone 40
"A tree never hits an automobile except in self defense." - Woody Allen