Abstract
The 5-point mixture method is used in a survey of the general situation of soil contamination. Its stochastic characteristics were analyzed. Weak stationarity, isotropy, and three types of covariance functions, exponential, Gausian, and spherical type, were assumed for the stochastic characters of a field to be analyzed. The genetic algorithm was used to find the best arrangement of sampling points that minimize the estimation variance in a 1000m2 square area. The results show that sampling points should be on the center of the area and about 13m apart from it, although it has been recommended for the standard method that they should be on the center and from 5 to 10m apart from it.
