基于数值模拟的某临河工业固体废物渣场地下水污染控制研究

Research on groundwater pollution control of a riverside industrial solid waste slag field based on numerical simulation

简易渣场无规范环保措施,是地下水和土壤的重要污染源。针对简易渣场,以彻底清除污染源和重新规范渣场建设为优先方案,但确无条件实施上述方案时,一些地方也采用封场配套物理阻隔和抽出-处理等措施,最大程度控制和缓解渣场对周边地下水环境的影响。以某临河工业渣场为例,建立了就地封场、就地封场联合水动力阻隔、就地封场联合防渗帷幕及抽出-处理方案的Modflow模型,模拟了各方案的控制效果。结果表明:封场虽可较快恢复渣场区地下水质量,但并未从根本上消除污染物;封场基础上在临河侧设置抽水量170 m^3/d的水井1口亦有较好的控制效果,但存在运行管理困难的问题;封场基础上联合帷幕注浆及抽出-处理,相对有一定优势,但运行管理仍有一定难度。因此,若条件允许,最好的方案仍是彻底清除污染源或重新规范渣场建设。

Simple slag without standardized environmental protection measures is an important source of groundwater and soil pollution.Completely removing pollution sources or re-regulating it is a priority plan.However,when unconditionally implementing the above schemes,some places also adopt measures such as physical barrier and extraction-treatment based on field sealing to minimize the impact of slag yards on groundwater environment.Taking a riverside industrial solid waste slag as an example,the Modflow models of in-situ closure,in-situ closure combined hydrodynamic barrier,in-situ closure combined seepage proof and extraction-treatment schemes were established.The numerical simulation results showed that:although the quality of groundwater around the slag would recover in a relatively short time,the pollutants can’t be eliminated completely;a well with pumping capacity of 170 m^3/d based on in-situ closure also has good control effect,but it has some problems in operation and management;combining curtain grouting and pumping-treatment based on in-situ closure has some comparatively advantages,but the operation management is still difficult.Therefore,the best solution is to completely eliminate the source of pollution or re-regulate the slag,if conditions permit.