tanglewood exploration not paying

I signed a marcellus lease with Tanglewood Exploration for my 127 acres in Greene County.  All was good until they put the well/frac pit on my property and will not pay me for it as the lease states.  The lease states:  If the well/frac pit are on any part of your property you get paid.  Tanglewood is saying that the site is only on 80% of my property and want to deduct 20% of the payment.  They won't even pay me for the trees they cut!  Needless to say, I would never sign a lease with this company and I regret doing so now.  They have also not paid the other two landowners for their supposed 20% or for the trees.  They also were to pay me for the gas pipe line and won't pay that either!