地下水型水源地水质安全预警技术体系研究

地下水型水源地水质安全预警是城镇集中供水的地下水资源保护和管理的重要依据.为了提高地下水型水源地水质安全预警功能，提出了包括基于水质长序列监测预警、基于污染动态模拟预警及基于区域污染风险评价预警的技术体系.其中，基于水质长序列监测的预警是通过因子分析筛选水源地特征污染物，分析水质数据变幅以确定水源地水质的预警级别，可实现针对水源井的开关控制作用；基于污染动态模拟的预警是在水源地外围污染源特征基础上，模拟其动态迁移过程，进而确定其影响水源地水质的预警级别，可实现对水源地水质变化趋势的预判；基于区域污染风险评价的预警着重于水源地受区域污染风险控制与水源地保护区的耦合效应，同时结合其他预警影响因子作用以确定预警级别，可实现对水源地所在区域的宏观管控.该技术在哈尔滨市利民水源地进行了综合应用，结果显示，基于水质长序列监测预警中，COD_Mn及NH₄+的最大变幅指数均在1~2之间，预警级别确定为一级；根据污染动态模拟的结果得知，位于水源地开采井流场上游较高ρ（NH₄+）的范围在迁移20 a后，污染晕前段尚未到达水源地，确定预警级别为零级；基于区域污染风险评价的预警确定水源地所在区域为零级预警区，综合分析可以确定利民水源地地下水水质存在污染风险，应采取相应的管控措施. 

Technological System of Early Warning for Groundwater Quality in a Groundwater Source Area

Having access to timely information about groundwater quality in groundwater source areas could be helpful for protection and management of groundwater resources that supply centralized urban water systems. We propose a new advanced early warning system that combines three aspects:analysis of long term groundwater quality monitoring data, simulations of pollutant transport, and a risk assessment of regional pollution. Through factor analysis of long-term water quality data, the main pollutants in the source water were identified. Threshold concentrations that could be used as alerts or thresholds within the early warning system were identified from the concentration ranges of the main pollutants. The characteristics of the external pollution sources were investigated and the transport of the main pollutants into the water source was simulated to determine the water quality warning levels of the source water. The quality of the source groundwater was also predicted. The regional pollution risk assessment examined the effect of coupling controls on the regional pollution risk with protection of the water source area, and considered the effect of early warning factors, how to determine the warning level, and how to control the groundwater source area at the macro level. Analysis of the monitoring data showed that the index of COD_Mn and NH₄⁺ concentrations were within the ranges of levels 1 and 2, and the warning level was level 1. From the simulation results, NH₄⁺ concentrations were highest in the upstream of the water source area and that, even after 20 years of migration, the high concentrations had not reached the water source area, and the warning level was zero. Based on the regional pollution risk assessment and analysis of the water quality monitoring data, the water source area was classed at level zero. The above results showed that it is possible to determine the risk of pollution of groundwater in the Lim in Water Source, and that control measures should be implemented in line with the actual risk.