A magisterial probe has found that faulty earthing led to the electrocution of 16 people at a Namami Gange sewage treatment plant in Uttarakhand's Chamoli and has recommended blacklisting of the two companies responsible for the STP's maintenance for violating safety norms.

The report of the probe, which was carried out by Chamoli Additional District Magistrate Abhishek Tripathi, also recommended power safety audits be conducted at all STPs to prevent such incidents.

The report of the probe was submitted to the state government on Saturday and released to the media.

It said the joint venture companies responsible for the electrification system at the STP violated terms of their contract and safety norms. It recommended cancelling their contracts and blacklisting them in Uttarakhand.

These joint venture firms are Jai Bhushan Malik Contractors, Patiala (lead partner) and Confident Engineering India Private Limited, Coimbatore.

There was a short circuit in the changeover panel and a sharp earth fault in the control and main panels. Due to the unavailability of proper earthing, the current passed through the metallic structures. The steps and railings leading to the plant were part of these metallic structures, the report said.

As a result, people who came in contact with the steps or railings got electrocuted. The earthing at the STP was not as per the norms, it said.

Lack of coordination between the Jal Sansthan and electricity department employees was also one of the reasons behind the incident, it added.

The report also recommended power safety audits of all STPs in the state to prevent such incidents in future.

Electric current ran through the steps and railings leading to the STP located on the banks of the Alaknanda River in Chamoli on July 18-19, killing 16 people and injuring 11.

The Uttarakhand Power Corporation Limited had said the incident took place after power was restored to the STP following a 20-minute shutdown for some repairs.

Four people, including the supervisor of the joint venture company, have been arrested in connection with the incident.

The prime objective of the Namami Gange programme is to make the water of the Ganga suitable for outdoor bathing.?