Methods and apparatus that provide grade-level RF transceivers for use in trans-grade wireless communication networks. The methods involve incorporating slot antennas into grade-level opening covers, such as manhole covers, to provide built-in antennas for transceivers that may be connected by transmission lines. The grade-level transceivers use coupling mechanisms to connect transceivers to the slot antennas by way of transmission feed lines. Multi-slot grade-level transceivers use switching mechanisms to switch between multiple slot antennas. Certain embodiments may also include adaptable RF circuitry. Trans-grade wireless communication networks use these grade-level transceivers to communicate between below-ground and above-ground portions of the network, which may be used in underground utility systems such as combined sewer systems.