This project will be implemented for 18 months, during which supplementary investigations, enhanced biological rehabilitation method trials, Regular monitoring and sampling, early warning monitoring well sampling, and other administrative tasks, etc., and planning area It is divided into three areas, namely the 91-2 site number of Yongzhen section, the site number 1182 of Yongzhen section, and Luzhunan Subsection 645-14 land number. The 91-2 site number of Yongzhen section adopts the natural attenuation method, which has been monitored regularly through this project and the past times Investigation The current site has completed the natural attenuation method assessment. In terms of risk management, the site number is currently underground Water restricted use area, restricted use of groundwater, and through pollution transmission mode and pollution site overview The establishment of a mental model shows that the site number is not in the hot zone of pollution transmission. It is recommended to continue monitoring for 2 years The monitoring frequency is carried out every six months. If they meet the groundwater control standards, you can report to Miaoli The county environmental protection bureau applied for the removal of the management. The site number of Yongzhen Section 1182 adopts the natural attenuation method, and the site has completed the natural attenuation method assessment. Implementation, the follow-up can perform monitoring natural attenuation assessment (MNA), the recommended monitoring time is 2 years, it is recommended It is recommended that the monitoring frequency be implemented once every six months. If all the groundwater control standards are met, the environmental The Protection Bureau applied for the removal of the pipeline, but the pollution transmission simulation showed that the area was due to monitoring wells. K00392 has found that the groundwater pollutant vinyl chloride exceeds the groundwater control standards. This area Located on the edge of a hot polluted area, there may be fluctuations in pollution concentration. No. 645-14 of Luzhunan Xiaoduan uses the biological restoration method for pollution improvement operations, and causes pollution according to Transmission simulation This area is a hot pollution area, and the effectiveness evaluation was found during the third effectiveness evaluation sampling Wells (M1-2) have exceeded the control standards, but this pollution rebound is likely to occur in the initial stage of pollution improvement In the case of shocks, the concentration of pollution recovery has not been higher than previous highs, and the concentration of the original monitoring wells in this area has not been There is no recovery, and the mass calculation result of the pollutants passed through the polluted area, the original pollutant throughput is 7.48E-02(g/day), the pollution amount passed after pollution improvement is 1.81E-03(g/day), showing the current The pollution in this area has been reduced, showing that the currently implemented enhanced biological restoration method still has There is a certain improvement effect.

Stagnation site, natural attenuation method, risk management