摘要
为探究抽水对含水层中污染羽形态及迁移速率的影响,开展了抽水条件下污染物在不同含水层迁移的示踪试验。结果表明,抽水会改变均质含水层(含水层1)中污染羽的形态,但对含砾石及粉细砂夹层的非均质含水层(含水层2)及含砾石通道的非均质含水层(含水层3)中污染羽形态影响不大。与不抽水相比,抽水速率为300mL/min时,含水层1、2、3中污染物的平均迁移速率分别增大了1.570、1.480、3.050cm/min,迁移60cm所用时间分别缩短了36、35、48min。可见,抽水对不同含水层中污染物迁移速率影响程度由大到小分别为含砾石通道的非均质含水层、均质含水层、含砾石与粉细砂夹层的非均质含水层。
Tracer experiments were carried out under pumping conditions to explore impact of pumping water on morphological of pollution plume and migration rate of contaminants in aquifer.The results showed that morphological of pollution plume of homogeneous aquifer(aquifer 1)changed with pumping,but pumping water had little influence on morphological of pollution plume of heterogeneous aquifer with gravel and sand interlayer(aquifer2),and heterogeneous aquifer with gravel channel(aquifer 3).Compared with no pumping,when pumping rate was300mL/min,the average migration rate of contaminant in aquifer 1,aquifer 2and aquifer 3was increased by 1.570,1.480 and 3.050cm/min,respectively.Time for contaminant migrating 60 cm in aquifer was reduced by 36,35 and 48min,respectively.Obviously,the impact of pumping on contaminant migration rate in aquifer was followed the order of heterogeneous aquifer with gravel channel,homogeneous aquifer,heterogeneous aquifer with gravel and sand interlayer.
引文
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