Nonvalence correlation bound anions are formed when an electron is bound by correlation effects in a very diffuse orbital far from the molecule. Theoretical methods that build upon the uncorrelated Hartree-Fock reference. As such, these methods serve as an interesting test of computational methods. In this work, we treat a model nonvalence correlation bound system, a water tetramer cluster, with quantum Monte Carlo (QMC) methods. It is found that QMC is able to quantitatively calculate the electron binding energy even when using a nonphysical Hartree-Fock trial wave function.