I don't think it is currently possible in NWChem. Only the undocumented and I-can't-figure-out-how-to-build-it Lucia code contains any reference to Brueckner orbitals. If you need free software that can do these computations you might try Psi4: http://sirius.chem.vt.edu/psi4manual/latest/cc.html
CFOUR is another free (as in beer, not GPL) code that supports Bruekner CC methods.