The study assessed the quality of highway runoff and a stormwater treatment system, focusing on intra-event variations (IEVs: variations within a runoff/effluent event) of the concentration of organic micropollutants (OMPs) including bisphenol-A, alkylphenols, polycyclic aromatic hydrocarbons (PAHs), and petroleum hydrocarbons (PHCs). IEVs of OMPs varied considerably with no particular recurring pattern in highway runoff and presedimentation effluent, displaying sporadic strong first flushes. IEVs are significantly associated with rainfall intensity variations, especially for particle-bound substances such as PAHs and PHCs. However, phenolic substances showed distinct IEV patterns compared to total suspended solids, PAHs, and PHCs, likely due to their higher solubility and mobility. Downstream sand filter (SF) and vegetated biofilter (BFC) mitigated IEVs, leading to more uniform discharge during outflow events. Although BFC’s IEVs were indiscernible due to low effluent concentrations, SF’s IEVs often peaked at the beginning of events (within the first 100 of ⁓600 m3), exceeding the lowest predicted non-effect concentrations for five PAHs, bisphenol-A, and octylphenol. This study highlights the advantage of IEV analysis over conventional event mean concentration analysis for identifying critical effluent stages, crucial for developing control strategies to protect sensitive water recipients or for reuse applications.

中文翻译：

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公路径流中有机微污染物的事件内变化和预沉淀生物滤池处理设施


该研究评估了高速公路径流和雨水处理系统的质量，重点关注有机微污染物 (OMP) 浓度的事件内变化（IEV：径流/污水事件内的变化），包括双酚 A、烷基酚、多环芳烃（PAH）和石油碳氢化合物（PHC）。 OMP 的 IEV 变化很大，公路径流和预沉淀废水没有特定的重复模式，显示出零星的强烈初冲。 IEV 与降雨强度变化显着相关，特别是对于 PAH 和 PHC 等颗粒结合物质。然而，与总悬浮固体、PAH 和 PHC 相比，酚类物质表现出不同的 IEV 模式，这可能是因为它们具有更高的溶解度和流动性。下游砂滤器 (SF) 和植被生物滤器 (BFC) 减轻了 IEV，导致流出事件期间排放更加均匀。尽管由于出水浓度低，BFC 的 IEV 难以辨别，但 SF 的 IEV 通常在事件开始时达到峰值（在⁓600 m3 的前 100 个范围内），超过了五种 PAH、双酚 A 和辛基酚的最低预测无影响浓度。这项研究强调了 IEV 分析相对于传统事件平均浓度分析的优势，可用于识别关键废水阶段，这对于制定保护敏感水接收者或再利用应用的控制策略至关重要。