CHANDIGARH: Using untreated water for construction, high levels of chloride in the concrete that was of inferior quality and poor workmanship have been cited as main reasons by the CBI for the partial collapse of Chintels Paradiso housing project’s Tower-D in Gurugram on February 10 last year.
A portion of the sixth floor had collapsed down to the first floor, leading to the death of two residents, Ekta Bhardwaj and Sunita Srivastava, and injuries to Arun Kumar Srivastava. In its supplementary chargesheet, the CBI said Gurugram fell under “overexploitation stage” of groundwater extraction. The groundwater had a high concentration of salts, making it unfit for construction, it said. The source of water was a borewell until September 2012 when the Punjab and Haryana High Court banned the use of groundwater for construction and only sewage treatment plant (STP) water was allowed.
An RO plant was installed at the site in August 2011 and a chemical dosing plant in September 2012 for treating STP water. “The RO plant was not used regularly during daytime construction and was never used at night…. After the chemical dosing plant was installed, the RO was never used to treat water,” said the CBI. The probe agency said sodium hypochlorite was used in the chemical dosing plant to remove odour and reduce PH/TDS levels, but it led to an increase in the chloride content in water. During a joint inspection by the project owner and the contractor in 2015 when cracks had appeared in the basement of towers, sample-testing led to the discovery of high levels of chloride in the concrete.
The CBI said IIT-Delhi experts had deployed ‘ultrasonic pulse velocity of concrete’ test, which confirmed poor quality of concrete and workmanship. The concrete samples failed core density test too. The chloride content was found to be 200 per cent higher than the permissible limit. The excessive chloride caused steel corrosion, which reduced the load-bearing capacity of the building and a portion of the tower collapsed.
The agency has written to the Town and Country Planning Department to act against senior officers Kamal Singh, Dinesh Chouhan, Ravi Sihag and Arun Gupta for the lapses. There are 10 accused in the case, including officials of Chintels India Pvt Ltd and Bhayana Builders Pvt Ltd, which carried out the construction.