Actually the Sierra Club is against illegal aliens coming into the US and is for curbing all US immigration.
I am no Enviro-Nutzie but it is important to note and applaud that one agenda they have.
When I was in San Diego, I ran into Brian Bilbrey, who was a congressman for a term or two. But his claim to fame was that, while the mayor of Imperial Beach (I think he was really young), he took a bulldozer to close the outlet of the Tijuana River Estuary. Why? Because the untreated sewage from the South flowed into the ocean, forcing the continuous closure of the beaches.
Add that to the fact the EPA considered the estuary "sewage-based", and therefore we would be "altering/changing an endangered species habitat", ignoring the fact that the tern's eggs (the protected species within that habitat) were being eaten for breakfast by the invading aliens..
Ironic, ain't it? No one really raised the issue of the impact of immigration upon the environment for quite some time. Now, with the fence in place, everyone is concerned about the "needless deaths" further East where the wall ends.
Pookie & ME