The Odisha State Pollution Control Board (OSPCB) has asked operators of chromite mines in Odisha’s Sukinda Valley, which accounts for more than 90 of India’s chromite reserve, to submit comprehensive action plan for overburden (OB) management.
OB is deposit of top soil and mining rejects which are dug out during surface mining. Dangerous hexavalent chromium reportedly leak through the OB in Sukinda Valley which is considered as one of top pollution hotspots in the country.
The lessees should incorporate number of active and inactive dumps, area of dumping and volume of OB stored as on date, proposals for re-handling of OB to recover chromite ore, stabilisation process being followed for OB and detail of runoff management, the OSPCB directed.
“Surface run-off of OB will not be allowed to be discharged outside without any treatment. The mines which have not installed real time monitoring facility at the inlet and outlet of effluent treatment plant will install the same by end of October this year to avoid revocation of consent order granted in respect of concerned mines,” the board ordered.
Tata Steel Limited and the State-run Odisha Mining Corporation (OMC) have been asked to complete the installation of online monitoring facility at the selected places in Damsalla Nalla, which has been polluted due to chromite mines, by November this year.
The Comptroller and Auditor General of India had pointed out deficiencies in treating waste water in Sukinda Valley. According to CAG, IIT-Kharagpur was assigned by the State Pollution Control Board to carry out a feasibility study on establishment of effluent treatment plant in Sukinda Valley. As per recommendation of IIT-Kharagpur, individual ETPs were to be upgraded to manage surface water containing dangerous hexavalent chromium.
“Nine out of 11 working chromite mine owners agreed to upgrade their ETPs during period ranging from September 2013 to June 2014. However, only four out of nine have done so till date (September 2014),” the CAG had pointed out.
Overburden is deposit of top soil and rejects which are dug out during surface mining
