LEESU ENPC, Université Paris-Est, 6-8 avenue Blaise Pascal, 77455, cedex 2, Marne la Vallée, France.
LEESU UPEC, Université Paris-Est Créteil, 61 avenue du Général de Gaulle, 94010, Créteil Cedex, France.
Environ Sci Pollut Res Int. 2022 Jan;29(3):3600-3615. doi: 10.1007/s11356-021-15491-0. Epub 2021 Aug 14.
An old industrial site (brownfield) located south of Paris in a flooding plain and containing demolition disposal as well as a burning zone for metal recovery is being regenerated to satisfy local need for public green space. The main objective of the described study was therefore to assess the risk of remobilisation of trace metals, PAH and PCB present. The research focused on vertical migration due to rainfall (non-saturated flow) and to river flooding (saturated flow). To assess the remobilisation risk, representative soil profiles were reconstituted and eluted in columns with artificial rain and filtered river water for 6 weeks with an equivalent of 25 mm d. Soil analysis showed that both zones are highly contaminated, exceeding the French environmental standards. Though the superficial metal content was much higher in the burning zone with levels of g kg than that in the demolition zone, most metals showed higher levels in the eluents of the latter. The level of dissolved Zn in the burning zone eluent was 30 μg L, while in the demolition zone, it was 300 μg L, 40 times the admissible level. Zn was thereby correlated to aromaticity parameter HIX, indicating a link with organic matter transformation. The Cu was only significantly released under saturated condition (up to 80 μg L) in the demolition soil, indicating as implicated mechanism manganese and iron oxide reduction rather than organic matter transformation. Despite the high PAH and PCB soil contents, these pollutants were not released. The total PAH content in the effluent was 30 ng L in average and did not significantly differ between the two zones and the types of hydrology. Only Zn and Cu issued from demolition zone presented an eco-toxicological risk. Crossed statistical analysis of the results showed that the role of the soil type is preponderant in the pollutant release and that temporary flooding condition would induce a lower impact on the groundwater quality than an equivalent amount of fallen rain. Though the burning site was far more contaminated in the upper soil than the demolition zone, it presented little risk compared to the demolition zone, more profound and more permeable. The latter showed therefore significative trace metal release, up to 2.1 kg ha year for zinc, doubling the local atmospheric deposition.
一个位于巴黎南部洪泛区的旧工业场地（棕地），其中包含拆除处置区和金属回收焚烧区，现正进行再生，以满足当地对公共绿地的需求。因此，本研究的主要目的是评估存在的痕量金属、多环芳烃和 PCB 再移动的风险。研究重点是由于降雨（非饱和流）和河流洪水（饱和流）引起的垂直迁移。为了评估再移动风险，代表性土壤剖面被重建，并在柱子中用人工雨水和过滤河水洗脱 6 周，相当于 25 毫米的降雨。土壤分析表明，两个区域都受到高度污染，超过了法国的环境标准。尽管焚烧区的表层金属含量（高达 30 g kg）远高于拆除区，但大多数金属在后一区域的洗脱液中含量更高。焚烧区洗脱液中溶解态 Zn 的含量为 30 μg L，而在拆除区则为 300 μg L，是可接受水平的 40 倍。Zn 与芳香度参数 HIX 呈正相关，表明与有机物转化有关。Cu 仅在拆除土壤中饱和条件下（高达 80 μg L）才会显著释放，表明机制涉及锰和氧化铁的还原，而不是有机物的转化。尽管 PAH 和 PCB 土壤含量很高，但这些污染物并未释放。废水中的总多环芳烃含量平均为 30 ng L，在两个区域之间和不同类型的水文条件下没有显著差异。只有来自拆除区的 Zn 和 Cu 呈现生态毒性风险。对结果进行的交叉统计分析表明，土壤类型在污染物释放中起主导作用，临时洪水条件对地下水质量的影响小于同等数量的降雨。尽管焚烧场地的表层土壤比拆除区污染更严重，但与拆除区相比，风险较小，拆除区更深厚、更具渗透性。后者因此表现出明显的痕量金属释放，锌的释放量高达 2.1 kg ha 年，是当地大气沉降的两倍。
