+----+ +-------+ +-------+ +----+ | R1 | | R10 | | R30 | | R4 | | L2 +--+ L1/L2 +--------------+ +-----------------+ L1/L2 +--+ L2 | | | | | L2 adj | | L2 adj | | | | +----+ +-------+ over | | over +-------+ +----+ tunnel | | tunnel +----+ +-------+ +--+---+--+ +-------+ +----+ | R2 | | R11 | | R21 | | R31 | | R5 | | L2 +--+ L1/L2 +-----------+ L1/L2 +--------------+ L1/L2 +--+ L2 | | | | | L2 adj | flood | L2 adj | | | | +----+ +-------+ over |reflector| over +-------+ +----+ tunnel +--+---+--+ tunnel +----+ +-------+ | | +-------+ +----+ | R3 | | R12 +--------------+ +-----------------+ R32 | | R6 | | L2 +--+ L1/L2 | L2 adj L2 adj | L1/L2 +--+ L2 | | | | | over over | | | | +----+ +-------+ tunnel tunnel +-------+ +----+