The main purpose of this project was to perform detailed soil surveys and improve the project of " Changhua County Agricultural Land Pollution Control Site Appropriate Measure Improvement Plan - East-west Sanzhen Irrigation District - Investigation and Improvement (A)". By means of soil dilution and soil excavation method with clean soil backfilled, the controlled pollution sites could relieve to control. Individual work items including submitting a work plan, pollution improvement plans, monthly performance reports, daily activity logs, progress reports, hosting orientations to farmers and landholders, confirming the degree of heavy metal pollution of former-polluted farmlands and recently-controlled farmlands, inspecting the restricted farmlands bimonthly to avoid abnormal use, defining the scope of polluted farmlands, site remediation by soil dilution, self-verification, third-party-verification, and fertility recovery, and finally relieving sites to control are implemented according to regulations. In addition to the scheduled work and that relevant to the contract, we also cooperated with the EPB to ensure quality, control the progress, host evaluation and review meeting regularly. The achievements of this project included (1) confirming the degree of heavy metal contamination for 190 polluted farmland (31.27 hectares), suggesting the remediation method, choosing 149 polluted farmland (26.12 hectares) to perform soil excavation method with clean soil backfilled, and performing soil dilution for the rest 41 polluted farmlands (5.15 hectares). Such remediation processed that passed evaluation could serve as the reference information for EPB. (2) We held 2 orientations to farmers and landholders. (3) Soil dilution and excavation method with clean soil backfilled was performed for 142 (24.57 hectares) and 1 (0.16 hectares) farmlands, and soil fertility was recovered for these sites to continue the agricultural activities and achieve the goal for soil sustainability and maintain national fitness.

Heavy metal pollution, Soil dilution method, soil excavation method with clean soil backfilled, Remediation in the polluted farmlands