"We're running into groundwater contamination problems. As an example, nitrates from [agriculture] is a big problem in this area, now. We are into groundwater quality management in York County and right around this area because of high nitrates… But it's from is agricultural production, and it's from the over-application of nitrogen fertilizer on the crops. More fertilizer was put on than the crop could use during that growing season. And then, when we get heavy rains or a wet year, or we over-irrigate – we water too much – we flush that nitrogen fertilizer down through that soil profile. And eventually it will get into the groundwater table, into the groundwater aquifer.
     "Once it gets into the aquifer its very tough to get out. And then, that causes problems for health problems. Basically it affects the ability of the blood in how it carries oxygen. And so, young infants can have problems with it. And it also affects the livestock, like hog confinement, hog operations. Young pigs will be affected the same way humans are…
     "It took us 30 some years to get in this fix. It's going to take us that long to get back out. There's not an instant fix.
     "The way to manage your fertilizer is to test the soil to see how much nitrogen is in the soil. And you can do that by taking the soil sample with a probe which is just a hollow pipe. And you shove it down in the soil and take a sample, say, at six inches, one at a foot, one at two foot, one at three feet. And you send those off to a soil lab and they'll analyze the soils. They'll come back and say, 'You have so much nitrogen in here.' And then based on that information, you decide how much more you're going to have to put on for the crop needs for the next season.
     "And the trick to it is is to apply the amount of nitrogen that the crop needs to get you a good yield. But don't apply more. Apply it at the time of year, if you can, that the plant needs it."

John Turnbull – Water Quality


Other Excerpts from John Turnbull’s Interview:

John in Vietnam
Anti-War Protests
Consumer Preferences
Natural Resource Districts
Surface & Groundwater