Pune: The National Green Tribunal (NGT) recently passed an order to construct a Sewage Treatment Plant (STP) on strict norms of BOD<10mg/L, suspended solids 10mg/L and nitrogen <10mg/L, Fecal Coliform <230 most probable number (MPN) 100mL in outlet all across India for existing as well as new STPs.
This order came after city-based activist Nitin Deshpande approached NGT in 2018 as Central Pollution Control Board (CPCB) and The Ministry of Environment, Forest and Climate Change (MoEFCC) had relaxed several norms and standards of Sewage Treatment Plants in India.
The order states that “as per the draft norms proposed by the Central Pollution Control CPCB in 2015 - the Biochemical Oxygen Demand (BOD) was <10 mg/L, Chemical Oxygen Demand (COD) was 50 mg/L, Total Suspended Solids (TSS) was <20mg/L, Total Nitrogen <10mg/L, Ammonical Nitrogen was, 5mg/L, Total Phosphorus was on no limits and Fecal Coliform was <100 mg/L”.
These standards were diluted in the 2017 notification by the MoEFCC - BOD was 30 and, 20 mg/L, COD had no limits, TSS was <100 and < 50, Fecal Coliform was <1000 and Ammonical Nitrogen, Total Phosphorus Total Nitrogen had no limits.
Deshpande said, “Scrapping the 2017 notification by MoEFCC, which had relaxed standards for upcoming STPs, the NGT has now ordered stringent norms for all existing and upcoming STPs in the country. The draft norms proposed by the CPCB in 2015 were diluted by the MoEFCC in 2017 notification, which essentially permitted more pollutants than what was allowed under the 2015 draft.”
An expert committee was formed by NGT comprising members from IIT Kanpur, IIT Roorkee, National Environmental Engineering Research Institute based in Nagpur and CPCB.
“The committee accepted the report and the NGT passed an order on April 30, 2019, to scrap the 2017 norms and instead follow the more stringent ones as recommended. Now, all STPs in India should be made on these standards,”Deshpande added.
