Experimental investigations of the behavior of the Kr $1{s}_{2}$ excited-state population in after-glow discharge plasmas are described. The number density of Kr $1{s}_{2}$ atoms was obtained by performing resonant absorption measurements at 8509 \AA{} $(\mathrm{Kr} 1{s}_{2}\ensuremath{\rightarrow}2{p}_{4})$ with a tunable GaAs laser diode. The narrow-width laser was tuned and swept through the entire resonant transition. The decay of the $1{s}_{2}$ species in the late afterglow was found to depend primarily on the decay processes for the $1{s}_{3}$ species. Analysis of the pressure-dependent decay curve in the late afterglow has been carried out to derive the diffusion coefficient as well as two-body and three-body destruction frequencies for Kr $1{s}_{3}$ excited species. The diffusion coefficient was found to be 49 ${\mathrm{cm}}^{2}$${\mathrm{s}}^{\ensuremath{-}1}$. The two-body collisional destruction rate was found to be 9\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}15}$ ${\mathrm{cm}}^{3}$/s. The three-body collisional destruction rate, which presumably indicates the rate of formation of the excited dimer $\mathrm{Kr}_{2}^{}{}_{}{}^{*}$, was found to be 53.6\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}33}$ ${\mathrm{cm}}^{6}$/s.