**4. Conclusion**

The pollution of soil and groundwater by the use of pesticides has become a serious condition all over the world. The soil pollution is not only present in huge areas, but also is repeated continuously, leading to permanent contamination, because the pesticide is used many times each year. Therefore, the conventional methods require high budgets, making their set-up and maintenance are impractical. The author proposed the use of a novel bioremediation method, namely BSIS. Using BSIS, degrading microorganisms can be self-immobilized at high density in the shallow layer with the help of a PGA polymer secreted by the *Bacillus* strain, and can rapidly degrade a pollutant *in situ*. The author applied the BSIS for acid rain and triazine herbicides by using model soil packed in a column. BSIS was effective to remediate soil acidified by the acid rain and polluted by the pesticide. Moreover, this BSIS has advantages in that it can be applied without any expensive apparatus and can operate easily and perma‐ nently. These results suggest that BSIS may be the best method for the bioremediation of soil pollution by pesticides, although further improvements in the microorganisms might be necessary for the practical application of the technique.

Everyone can freely study and use our BSIS method without any restrictions by a patent. Therefore, the author expects that many researchers will recognize the advantages of BSIS, and by further improvements, it can applied for the pollution by pesticides, which is a serious worldwide problem.
