Your specifications list two airlift pumps (one recirculation and one discharge). Can the discharge airlift pump deliver pressurized effluent to a subsurface disposal system?

No.  Both airlift pumps use pressurized air (from the blower) to carry water via ascending bubble fluid pressure.  The discharge airlift pump lifts treated effluent from the treatment tank but depends on gravity to carry it to a subsurface disposal system.  You must specify a separate discharge pump for pumping effluent if a head is necessary.