In some agricultural areas a significant, if not dominate, source of Nitrates in the water is from fertilizers used for crops. See especially Chapter 6 of this link {I quote start of one sub section now). The above "already" is 5+ years old. SUMMARY of two quotes: Very dumb the US program for corn based gasohol. More pollution than gasoline, more global warming than gasoline's GHGs, more farm subsidy cost to tax payers, higher grocery cost with ~1/2 {See graph at end) of corn crop not used as food {for chickens, etc. and people} but alcohol production that at best has only 10% more energy than the energy used to produce it from corn; But GWB set it up to gain a few, very few, but very rich new big contributors to his campaign funds. {My first of many threads telling this was called "How dumb can US voters be?" which I posted when GWB was campaigning for his second term - I got my question answered by that election.} BTW a well done study by Cornell concluded corn based alcohol had only 90% of the energy used to make it! University of Iowa, disagreed as did several other studies with financial interest in the corn to alcohol program. * Paul Crutzen, I believe was first widely recognized authority to show this. In cold / short growing season, Iowa, so much nitrogen fertilizer is used to speed corn growth that most of it ends up being converted to NOx by soil bacteria – according to Noble Prize winning Crutzen. Also interesting from Paul Crutzen's 1995 Noble Prize Lecture at: http://www.nobelprize.org/nobel_prizes/chemistry/laureates/1995/crutzen-lecture.pdf on page 201, is table 1 {which in PDF I can't copy) but it shows how UV light of less than 321nm makes the OH radical that gets into the troposphere as a molar ratio fraction of 4x10^-14 as measured some years earlier (than 1995) or in other words ~10^6 molecules / CM^3. That table 1 also tell that the OH radial destroys CH4 with 50% chance any CH4 molecule will be oxidixed to water and CO2 within 8 years. i.e. had a half life of 8 years some time before 1995, but now so much CH4 is being released that it is the OH radiacal being destroyed by CH4 faster than OH can be produced, so the half life in 2013 was 12,6 years. Soon to be ~20 years. During the first decade after its release each gram of CH4 makes the global warming effect of more than 100 grams of CO2 (called its GH “potential”} More referenced details: The link's is somewhat old, (May 2009) but a very complete discussion of bio-fuels, their global potential, differences in engines, etc. One more problem with the new sciforums is that use of parentheses makes the enclosed words all run together with no spaces and be in italic. (why I use this mix} Please Register or Log in to view the hidden image!This graph terminates about 2011 - is from different source.
The nitrate fertilizer runoff and bacterial conversion problem may be reduced by the spread of no-till methods (originally made possible industrially by a GM developed by Monsanto, give the devil their due), but motor fuel from temperate zone corn has more problems yet - landscape destruction and ecological damage large among them. And the transition through the crunch time, when the absurdly shortsighted abuse of glyphosate (herbicide key to the GMOs involved} has burned it out, will be - as they say - interesting. Meanwhile, the mood in my corner of the midwest is celebratory - gasoline has dropped below $3 per gallon, the KC baseball team is great to watch, Obama's malign powers are about to be curbed in favor of Republican patriotic American Christian family values restored to primacy in national politics, and a bunch of jobs paying around 25k a year have opened up. My neighbors have the memory span of fruit flies, I think.
And like fruit flies, a little radiation (from TV political ad) can greatly change their form, belief systems & votes.
So glyphosate, among the least dangerous of broad-spectrum herbicides, is burning out under the abuse inherent in the GMO setup - but the agricultural infrastructure built around the GMO setup is embedded, not going away: instead, more toxic and dangerous herbicides are drafted into service. One term for this: "chasing the dragon".
