Hi Gregeden
Yes a barrier string would be correct process to use. The example linemode code below shows how to set this up.
INTERFAC,GROUNDMODEL,NEWWORKMODEL
260,MAST,ICUT,IFIL,1
261,IGN,CHR1,I001,3,0.125,,1.0
261,BARR,,I002,,3.000,7=0.05
261,IGN,,I003,5=5.000,7=0.5
261,IGN,,I004,5=2.000,7=0.01
261,AUTO,7=0.5
262,IGN,CHR1,I001,3,0.125,,1.0
262,BARR,,I002,5=3.000,7=-0.05
262,IGN,,I003,5=5.000,7=-0.5
262,IGN,,I004,5=2.000,7=-0.01
262,AUTO,,7=-0.5
263