The proposal to let off treated sewage from a gas-powered plant at Yelahanka into the Yelahanka lake has come under scrutiny from the Karnataka State Pollution Control Board (KSPCB). In a letter dated August 9, a copy of which is with The Hindu , KSPCB had expressed reservations about the Sewage Treatment Plant (STP) envisioned as a part of the Rs. 1,570-crore project.
While seeking approval for the treatment plant, the Karnataka Power Corporation Ltd. (KPCL) had proposed treating trade effluents (supplied from STPs at Jakkur, Hebbal and Yelahanka) through ultra-filtration and two-stage reverse osmosis to use within the plant. However, this generates around 190 m3 (around 1.9 lakh litres) per hour of treated waste water per day that was proposed to be let off into the 310-acre Yelahanka Lake.
The released water will have a Total Dissolved Solids (TDS) ranging from 6,000 to 7,000 mg per litre — more than 12 times the prescribed limit of 500 mg per litre.
KSPCB had then sought a report from the regional officer who pointed out that the recently-rejuvenated water body was being used for fishing. KPCL officials are yet to reply to the notice.
Residents’ fears
Behind high walls, six chimneys quietly tower over a large green space, while the background boasts of large residential complexes. It was years of protest that saw the diesel generator power plant at Yelahanka fall silent.
However, as work steams ahead to retrofit it as a gas power plant, fear of widespread pollution, noise and even water pollution has returned. “It was nearly impossible to stay in the area. We could not open our windows as there was dust and smoke entering our homes,” Manjunath, a shopkeeper at Kenchanahalli, which abuts the rear end of the power plant said.
Officials said the construction work was on schedule and the plant is expected to be operational in 2018.
“We are putting acoustic suppressors around turbines to reduce noise. Similarly, plantations will be increased within the 102-acre campus to reduce any impact,” said a Chandrakanth Dondiba, Chief Engineer (Gas, Solar & Wind).
“(However) the project is in the middle of a core residential area…While Liquefied Natural Gas is considered less polluting, the emission level will be above the limits for residential catchments,” says an online petition by residents against the project.
Not everyone thinks that restarting the plant is a negative idea. “When the apartment dwellers stopped the plant, we lost power in the area for over four months. The area needs electricity, and restarting this plant will see us getting good supply of electricity,” said a Bescom lineman living in the area.
Yelahanka Combined Cycle Power Plant
Project cost:
Rs. 1,571 crore
Seeks to generate
370 MW of power
Will retrofit a diesel power plant that was closed down owing to environmental concerns
in 2013
Spans 120 acres
in Yelahanka
Expected to be complete by March 2018
Currently, CNG supply by GAIL India supplied till Kuvempu Circle, around
10 km away
Environment Clearance issued on September 1, 2015
concerns
Air pollution: Nitrous oxide will be released.
KPCL claims overall
concentration will be
lower than 50 parts per million (permissible limit)
Water pollution:
Expected to generate around 1.9 lakh litres of waste water an hour.
Waste will have dissolved solids 12 times above permissible limit. KSPCB strikes down proposal
to release waste water into Yelahanka lake.
Noise pollution:
Expected to produce around 85-90 decibels of sound (close to the plant).
Permissible limit in industrial areas: 75dB
However, residents say the area should be considered a residential area for which the permissible
limit is 65dB.
