Nope. I work in environmental testing, and I know just how much stuff leeches into the soil. The amount of chemicals used in embalming, the amount of oil and crap probably leaking off the digging equipment...not a chance.
If it was a very old graveyard, predating all the stuff, no problem.
If you think about it, the earth is one big graveyard. Something has died and gone back to earth on and in every square inch of it.