某河道历史遗留固体废物堆存场地环境污染风险评估与综合治理方案
Study on Environmental Pollution Risk Assessment and Comprehensive Treatment Plan of a Historical Solid Waste Storage Site in a River Course

以某河道内的历史遗留固体废物堆场为例，通过对该研究区场地周围的土壤、固体废物、地下水、地表水现场采样及室内测定，检测样品中重金属及其他特征污染物的含量，分析其污染特征及原因并开展风险评估，结果表明：1) 土壤及底泥不存在污染物超标情况；固体废物出现pH与氟化物超标为II类固废情况；地下水超标因子中有锰、挥发酚、氨氮、氟化物超过背景值的情况；地表水有pH、溶解氧、五日生化需氧量、氟化物、氨氮、总氮、挥发酚、阴离子表面活性剂超标现象；2) 通过反距离插值法对土壤污染物空间范围进行模拟，将风险评估范围划分为重点防控区与一般防控区，风险评估重点关注场地内地下水的特征污染物。地下水关注污染物氨氮、锰和挥发酚危害商均小于1，风险可接受；氟化物危害商为7.5 > 1，其中饮用地下水暴露途径贡献率为100%。本次评估主要计算地下水中关注污染物氟化物的风险控制值为1.8 mg/L，实际参考值为1.0 mg/L。3) 提出河道固废整治方案：1、地表水抽至污水处理站处理；河道内转移对人体健康影响较大II类固废进行堆土造景，并建设人工湿地、种植耐碱草本植物对河道污染物进行长期治理，并实施定期环境监测。
Taking the historical solid waste dump in a certain river channel as an example, through on-site sampling and indoor measurement of the soil, solid waste, groundwater, and surface water around the site in the study area, the contents of heavy metals and other characteristic pollutants in the samples were detected, and the analysis was carried out. Its pollution characteristics and causes and risk assessment were carried out. The results showed that: 1) There were no pollutants exceeding the standard in soil and sediment; solid waste with pH and fluoride exceeding the standard was classified as Class II solid waste; the groundwater exceeded the standard factors in-cluding manganese, volatile phenol , ammonia nitrogen, and fluoride exceed the background value; surface water has pH, dissolved oxygen, five-day biochemical oxygen demand, fluoride, ammonia nitrogen, total nitrogen, volatile phenol, and anionic surfactants exceed the standard; 2) through inverse distance interpolation. The method simulates the spatial range of soil pollutants, and di-vides the scope of risk assessment into key prevention and control areas and general prevention and control areas. The risk assessment focuses on the characteristic pollutants of groundwater in the site. The hazard quotients of the pollutants of concern in groundwater ammonia nitrogen, manganese, and volatile phenols were all less than 1, and the risk was acceptable; the hazard quo-tient of fluoride was 7.5 > 1, and the contribution rate of drinking groundwater exposure was 100%. This assessment mainly calculates that the risk control value of fluoride, a pollutant of concern in groundwater, is 1.8 mg/L, and the actual reference value is 1.0 mg/L. 3) Propose a plan for river course solid waste remediation: 1. Surface water is pumped to the sewage treatment station for treatment; class II solid waste transferred in the river course has a greater impact on human health, and soil landscaping is carried out, and artificial wetlands are built, and alkali-resistant herbs are planted. Conduct long-term treatment of river