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Charged current interactions of neutrinos inside the Earth can result in secondary muons and {\tau} - leptons which are detectable by a large swath of existing and planned neutrino experiments through a wide variety of event topologies. Consideration of such events can improve detector performance and provide unique signatures which help with event reconstruction. In this work, we describe NuLeptonSim, a propagation tool for neutrinos and charged leptons that builds on the fast NuTauSim framework. NuLeptonSim considers energy losses of charged leptons, modelled both continuously for performance or stochastically for accuracy, as well as interaction models for all flavors of neutrinos, including the Glashow resonance. We demonstrate the results from including these effects on the Earth emergence probability of various charged leptons from different flavors of primary neutrino and their corresponding energy distributions. We find that the emergence probability of muons can be higher than that of taus for energies below 100 PeV, whether from a primary muon or {\tau} neutrino, and that the Glashow resonance contributes to a surplus of emerging leptons near the resonant energy.

Ultra-High Energy (UHE) neutrinos over $10^{16}$ eV have yet to be observed but the Askaryan Radio Array (ARA) is one in-ice neutrino observatory attempting to make this discovery. In anticipation of a thorough full-observatory and full-livetime neutrino search, we estimate how many neutrino events can be detected accounting for secondary interactions, which are typically ignored in UHE neutrino simulations. Using the NuLeptonSim and PyREx simulation frameworks, we calculate the abundance and usefulness of cascades viewed by multiple ARA stations and observations made of taus, muons, and neutrinos generated during and after initial neutrino cascades. Analyses that include these scenarios benefit from a considerable increase in effective area at key ARA neutrino energies, one example being a 30% increase in ARA's effective area when simulating taus and muons produced in $10^{19}$ eV neutrino interactions. These analysis techniques could be utilized by other in-ice radio neutrino observatories, as has been explored by NuRadioMC developers. Our contribution showcases full simulation results of neutrinos with energies $3\times10^{17}$ - $10^{21}$ eV and visualizations of interesting triggered event topologies., Comment: For 2023 ICRC, 8 pages, 7 figures, 1 table