12/5/2011 10:12 PM
I agree with all above, however sometimes if you really look at the ground the grass will be thinner or thicker over a pipe because the ground was worked years ago. May even be a slight swale in the earth. Also mark out all pipe location you can find and joints are normal at 20 foot apart. Look for 90 degree or 45 degree places it could be. It is kind of like an old test in school that is multiple questions old of out of 4, 2 are bad for sure and then you are down to 50%.
Keith
Zama