This letter investigates contactless power line communications (CPLC) for underground mining by modeling power wires as long-wire antennas. A system-level framework is developed, comprising a cascade of RF and power line channels. The model accounts for multipath propagation, frequency-dependent attenuation, and Rician fading. Simulations from 1-20 GHz reveal that the length of the wire significantly affects radiation, directivity, and input impedance. The findings show that CPLC transmits electromagnetic waves without direct electrical contact, offering a robust, cost-effective solution that enhances mobility, reduces maintenance, and ensures compatibility with existing mining power infrastructure.