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So the good thing about your spring is that it is high in nitrates.
The bad it is high in salt, most of the SW/cali soil is high in salt so that is not really surprising.
I would plant every/anything in the mint family (mint, thyme, rosemary, oregano, sage, basil, etc) they dont mind the salt that much. Plantains (Plantago spp.), and also the beet family ( spinach, beets, chard, quinoa, and sugar beets, amaranth) too.
You could also plant saltbush, it will store the salts and then you can dump it off property to lower your property salt level.
Try mulching the area it lower the odds of you getting more white salt deposits.
You can also plant beach plum in grown in salt water, sea kale, and pretty much any plant that has the word sea/salt/marsh/beach in its name, they grow in "salty" water.
Here are a few more salt tolerant plants.
http://en.wikipedia.org/wiki/Halophyte
Try a few cold hardy banana they love the nitrates, not too sure about the salt, though, but they are high in potassium, so maybe.