The application discloses a contaminated site remediation method and a degradation period evaluation method, and comprises the following steps: step 1, determining a
pollution range, setting a sampling point in the contaminated site, taking a
groundwater sample at the sampling point, and measuring the concentration of an
electron acceptor and the concentration of a degradation product; step 2, according to the measured concentrations of various indexes at different periods, calculating the cumulative percentage of various indexes at different periods, taking the concentration of the
electron acceptor or the concentration of the degradation product as the horizontal coordinate, and the corresponding cumulative probability as the
vertical coordinate, and drawing a cumulative probability distribution curve of each monitoring index; step 3, threshold range acquisition: according to the cumulative probability distribution curves of different
electron acceptors or degradation products obtained in step 2, the threshold range of the stable section of different electron acceptors or degradation products is acquired; step 4, calculating the degradation capacity; and step 4, calculating the
aquifer biodegradation rate. The method is specific for utilizing the conversion relationship between the
electron acceptor and the pollutants, and can quantitatively evaluate the degradation capacity and the degradation rate of the pollutants.