A laboratory prototype frequency domain electromagnetic induction sensor array suitable for simultaneous operation with an array of cesium vapor total field magnetometers has been designed and fabricated and has undergone limited bench testing. The design is based on the GEM-3 active primary field cancellation technology, which creates a "magnetic cavity" for each receive coil in the array. The array's magnetometers would be mounted inside the receive coils, within the magnetic cavities. This is very important because the primary transmit field would otherwise be strong enough to shift the total magnetic field vector (static magnetic field plus EMI components) outside the operating envelope of the magnetometers. Because the array configuration does not have the symmetry of a standard GEM-3, in-phase drift tends to be more severe. Tests with the prototype array show drift rates roughly one order of magnitude larger than with a standard GEM-3. However, demedian filtering such as that used for the MM-0033 towed GEM-3 array can correct for the drift. The most serious issue for the array is structural rigidity. When the array is bent, the bucking coils do not properly cancel the field from the outer transmit loop. Calculations indicate that bucking errors amounting l0's of ppm can be caused by bending the array by a few tenths of a degree over a distance of about 30 cm. The array would have to be held stiff to this sort of tolerance. For towed applications on land this may be difficult because the array will be subjected to significant bending stresses as it is towed over any realistic terrain. The bouncing and jostling motions for vehicle towed systems tend to have scales comparable to those of buried UXO signals. The situation may not be so serious for marine applications where the array would be buoyed up and not subject to such severe stresses.