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No reprieve for Bichhri

  • 29/04/1996

The National Environmental Engineering Research Institute study, carried out at the behest of the Supreme Court, lists the 'dewatering' of the aquifer around Bichhri as a measure to repair the damage done by the H-acid plants. But environmental engineer and senior professor of Aligarh Muslim University, R L Siddiqui, explains that this is not really an option for the following reasons:
Dewatering is a valid measure only if the pollutant is added to the well directly (for example, a putrefying animal body/waste added to the well)

If the ground water is pumped out, there will be a continuous inflow into the aquifer from adjoining sources, which in turn is recharged by surface sources (lakes, rivers, etc) or directly by rain water

In the present case, it implies that good quality water (probably from Udaisagar canal) will percolate through the soil and scrub it clean of the absorbed pollutants.

A highly impractical proposal if one considers the volume of soil to be scrubbed: a minimum of 2 sq km area x 10 m deep, that is, 4 million cu m

Consider the energy required to pump out that water (more than 4 million cu m, since 2x106 M2 (area) x 4 m (average water depth) x 0.5 (porosity) = 4 x 106) and the volume of good clean water which will be ultimately wasted

How will this waste water, with a toxic content several times more concentrated than sewage waste, be disposed?

A comparison of the observations taken before and after the monsoon, when the water table had risen by about 2 m, shows no dilution of pollutants. In other words, even the addition of about 2 million cu m of good water (2 X 106 M2 (area) x 2 m (rise in water level) x 0.5 (porosity) = 2 X 106 M3) did not have any dilution effect. This water amounts to the water requirement for a village population of 10,000 for 10 days at the rate of 20 litre per capita per day.

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