New Delhi: Nearly half of the 3,145 highly polluting industry units that were issued notices by the Central Pollution Control Board (CPCB) in 2015 have installed effluent/emission monitoring systems, the environment ministry said on Monday.

In 2015, CPCB issued notices to industry units under 17 categories, asking them to install continuous effluent/emission monitoring systems. Of the total 3,145, 1,475 have installed the devices and 805 are expected to do it by March end.

The government closed 321 polluting industry units asking them to re-open it only after putting in place the devices. Closure orders were issued to 141 others and action is being initiated against the remaining 403 industry units, the ministry said.

“The earlier method of physical sampling and lab testing was found to be inadequate as it could not capture pollution levels 24 hours. With online monitoring the situation has completely changed and monitoring can be done continuously. We shall also bring about necessary changes in law to enable use of on-line data as legal evidence," said environment minister Prakash Javadekar at a press conference.

The minister said that at least 200 industry units are exceeding their permissible limits more than once a day and those are the industry units the ministry is focusing on now.

The emissions covered under continuous monitoring systems include particulate matter, sulphur dioxide, nitrogen dioxide, carbon monoxide and ammonia and effluent parameters include flow, pH (hydrogen potential), bio-chemical oxygen demand, chemical oxygen demand, total suspended solid and ammonical nitrogen.

Data connectivity has been established between 1,101 units and the CPCB. Text messages and emails are automatically generated whenever the emission or effluent standards exceed the permissible limits for more than 15 minutes. Text messages are sent to stakeholders such as CPCB, State Pollution Control Board and the concerned industry.

“This is a big step forward in regulation and this is a big boost to the clean India campaign. The industry has also responded positively and has improved their procedures to minimize pollution," Javadekar added.