The propagation of electrostatic waves is studied in plasma system consisting of pair-ions and stationary additional ions in presence of the Sagdeev potential (pseudopotential) as function of electrostatic potential (pseudoparticle). It is remarked that both compressive and rarefective solitary waves can be propagated in this plasma system. These electrostatic solitary waves, however, cannot be propagated if the density of stationary ions increases from one critical value or decreases from another when the temperature and the Mach number are fixed. Also, when pseudoparticle is affected with a little dissipation of energy, it is trapped in potential well and can oscillate. Oscillations generate shock wave in the media, and in the negative minimal point of the well it is possible to compute numerically the shock wavelength for the allowed values of the plasma parameters.