Observations of gamma-ray bursts in the 1 GeV–1 TeV energy region are of great interest for the understanding of these mysterious events. The detection of GeV-TeV gamma-ray bursts is feasible using extensive air shower arrays
monitoring the fluctuations of the single-particle counting rate. The sensitivity is strongly increased working at mountain altitudes, in particular above 5000 m. In this
paper we discuss the possibility to exploit the existing BASJE EAS array operating at Mt. Chacaltaya (Bolivia) at 5200 m a.s.l. Simulations of electromagnetic showers in the atmosphere have been performed in order to evaluate the sensitivity of this experiment to detect gamma ray bursts of different time duration, spectrum slope and energy
cut-off. The detector can observe events of energy fluence F(ED1 GeV )A few 1025 erg cm22, comparable to that measured by satellite instruments during the most intense gamma-ray bursts, provided they occurr at low zenith angles and
assuming that the energy spectrum at least extends up to A1 TeV. In the case of events below the sensitivity of the experiment, upper limits on the high-energy tail of the spectrum can be obtained by measurements in coincidence with satellite observations