Column leaching and sorption experiments to assess the mobility of potentially toxic elements in industrially contaminated land.

Made-up ground collected from layers of a trial pit excavated on a former industrial site was treated with artificial rainwater in a series of column leaching and sorption experiments. Metal mobility and the ability of various layers of material obtained from the pit to act as sources or sinks of potentially toxic elements were assessed. Samples from different layers varied in their abilities to raise the pH of rainwater applied at pH 3.5 and 4.3, and this was reflected in the amounts of metals mobilised by the rainwater as it percolated through the soil column. Material from the top two layers of the pit released cadmium, copper, manganese, lead, nickel and zinc to the aqueous phase, but the lower layers, with higher buffering capacity, were able to resist acidification even when the equivalent of 12 months' rainfall (western UK) was applied. Column sorption experiments confirmed the ability of material from layer 4 (48-50 cm) to take up copper, manganese and zinc. Metals were determined in the leachates by flame and electrothermal atomic absorption spectrometry and principle anions by ion chromatography.

在一个曾经的工业场地上挖掘的探坑中采集的人工堆积土，在一系列柱淋溶和吸附实验中用人工雨水进行了处理。对金属的迁移性以及从探坑中获取的不同土层作为潜在有毒元素源或汇的能力进行了评估。不同土层的样本在提高pH值为3.5和4.3的雨水的pH值的能力上有所不同，这反映在雨水渗透过土壤柱时所迁移的金属量上。探坑顶部两层的物质向水相中释放了镉、铜、锰、铅、镍和锌，但具有较高缓冲能力的下层，即使施加相当于英国西部12个月降雨量的雨水时，也能够抵抗酸化。柱吸附实验证实了第4层（48 - 50厘米）的物质吸收铜、锰和锌的能力。通过火焰原子吸收光谱法和电热原子吸收光谱法测定了渗滤液中的金属，通过离子色谱法测定了主要阴离子。