Publication - 1 December, 1999
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Executive summary: Following a sampling and analysis programme carried out in 1996, in May 1999,Greenpeace International carried out a further programme at industrial estates located atAnkleshwar, Nandesari and Vapi in Gujarat, India. These estates consist of an estimated 3,000, 300 and nearly 2,000 industrial units respectively. The industries utilise common effluent treatment plants (CETPs) to varying degrees to treat process waste streams.Considered individually (and in aggregate) the diverse chemical manufacturing processesinvolved generate highly complex waste streams for which techniques to deal with them either do not exist or are unproven in practical application (Englande 1994). Commoneffluent treatment plants have been promoted in the region as a long-term solution to theenvironmental problems arising from contaminated wastewater disposal. This report utilises data from samples taken from the open waste-water channels and common effluent treatment plants (CETPs) associated with these industrial estates and from thesurrounding environment to demonstrate that in a large majority of cases, such plants donot adequately treat industrial effluents generated by these industries. Accordingly,environmentally significant chemical contaminants, rather than being treated and degradedare still being discharged to the wider environment.Comparison of sample results obtained in 1996 with those obtained from the currentprogramme in 1999 revealed that similar profiles of persistent organic pollutants and heavy metals to be present in samples. The CETPs were brought on line subsequent to the 1996 programme and presumably were intended to address the diverse chemical mixtures being discharged. This strategy has demonstrably failed. In one instance wider range oforganic contaminants was found and included, specifically, brominated compounds and the insecticide chlorpyrifos. In both 1996 and 1999 the Greenpeace Internationalprogrammatic studies in the vicinity of the Ankleshwar estate demonstrated the widespread occurrence of inter alia chlorinated benzenes, chlorinated benzenamines, certain polychlorinated biphenyls, chlorinated toluenes and brominated organic compounds. Moreover, the widespread contamination of the Ankleshwar area with elevated levels of copper is indicative of the generally inadequate process control and waste management practices employed on this estate.Common Effluent Treatment Plants are known to concentrate heavy metal contamination in solid residues, which far from providing a solution, is merely the transfer of contamination from one environmental medium to another and is associated with specificwaste disposal problems. Notwithstanding this cadmium levels in the effluent from theCETP on the Vapi industrial estate clearly demonstrate that not all the heavy metals are removed from the liquid phase, resulting in significant, direct, discharges to aquatic systems outside the plant. Further confirmation of the relative inefficiency of CETPS indegrading chemicals present in the influent stream is provided by sludge/sediment samples taken at Ankleshwar. In this case, samples of sludge collected adjacent to the final settling lagoon of the CETP on Ankleshwar were found to contain the same organic contaminants as sediment samples taken from the Amlakhadi channel into which this plant discharges.The influence of historical discharges may be largely discounted. The presence ofchlorinated and brominated benzamines, which are generally accepted as having a shortenvironemental half-life indicates that recent discharges to the channel are responsible forthis contamination.The widespread impact of poor management and control practices is illustrated by groundwater samples taken in the vicinity of Sarigam. This is located a few kilometres south of the Vapi industrial estate. Upon analysis, this groundwater was found to contain trichloroethene, benzene, chlorobenzene, 1,3- and 1,4-dichlorobenzenes. Theconcentration of trichloroethene present exceeded the US EPA permissible levels set fordrinking water by a factor of four. Benzene is a known human carcinogen and dichlorobenzene is a persistent organic contaminant that is itself resistant to microbial breakdown and is suspected to inhibit the microbial degradation of other chemicals.This report highlights the complexity of the chemical mixtures that continue to bedischarged and to persist in the environment in the Gujarat region. In this context it also discusses the limited utility and effectiveness of current treatment plants and outlines the need for an overall waste treatment strategy with a long-term goal of elimination of priority pollutants at source.
Num. pages: 33
ISBN: 90-73361-61-3