We report in detail on searches for eV-scale sterile neutrinos, in the context of a 3+1 model, using eight years of data from the IceCube Neutrino Telescope. By analyzing the reconstructed energies and zenith angles of 305,735 atmospheric νμ and ¯νμ events we construct confidence intervals in two analysis spaces: sin2(2θ24) vs Δm2¦41 under the conservative assumption θ34=0; and sin2 (2θ24) vs sin2 (2θ34) given sufficiently large Δm2¦41 that fast oscillation features are unresolvable. Detailed discussions of the event selection, systematic uncertainties, and fitting procedures are presented. No strong evidence for sterile neutrinos is found, and the best-fit likelihood is consistent with the no sterile neutrino hypothesis with a p value of 8% in the first analysis space and 19% in the second