Minimal presence of effluents : NIT report
Source: The Sangai Express

Imphal, January 22 2024: There is minimal presence of effluent and oil contamination in minor channels at Khanglapokpi, said NIT Manipur experts investigating water after the Leimakhong power station oil spill.

A report, the National Institute of Technology Manipur published today said the Total Dissolved Solids (TDS) recorded at the upstream, diversion point and downstream at Khanglapokpi have been found to be 218.5 ppm, 103.3 ppm and 69.85 ppm respectively.

This indicates the minimal presence of effluents and oil contamination in the minor channels, it said.

From the in-situ site sampling of the contaminated water, pH (potential of hydrogen) values of the upstream at Khanglapokpi, at diversion point and downstream point where Khanglapokpi and minor drainage confluence with Luwanglei stream are found to be 7.75, 7.19 and 7.63 respectively, suggesting the ability of the stream to dilute at downstream.

The Total Suspended Solids (TSS) recorded at the three locations averaged out to 0.093 mg/litre.

While the organic content is almost negligible, traces of heavy oil residue as debris are found in the upstream samples, said the report.

As per Indian Standards, the permissible limit of TSS for potability is 500 mg/litre.

Total Suspended Solids (TSS) refers to water-borne particles that exceed 2 microns in size.

Any particle that is smaller than 2 microns, on the other hand, is considered a Total Dissolved Solids (TDS).

The report said separation of heavy fuel and residues from the stream water is underway.

The water still needs to be tested further for toxicity and other related carbon compounds.

The laboratory of Civil Engineering Department, NIT Manipur is conducting the tests which will give further insights into the water quality and safety criteria for potability, said the report.

The report further mentions that traces of oil effluent could be observed in small contents at the confluence point of the Khanglapokpi Khong and other minor drainage channels in Leimakhong and Khurkhul and further down to Luwanglei stream.

The effluent discharge along Luwanglei stream needs to be further examined in detail for possible flow dispersion in the stream down through Loitang Khunou, Kameng, Mayang Langjing, Lamdeng before discharging into the Nambul river, as well as along the Leimakhong river at upstream point at Leimakhong-Kanto area, it said.

The experts carrying out the investigation includes Dr Ng Romeji (Hydrology & Hydraulics), Prof Bakimchandra (HoD, GIS & Remote Sensing), Prof Dr Albino Kumar (Environmental Engg), Dr A Azhoni (Climate Change) PhD Research Scholar Mukesh Yadav, MTech students Sandy Thingujam and Ksheroda Sapam.

The tests at the laboratories of Civil Engineering (Environmental) and Chemistry Department are being carried out with the support of Dr W Sujata, Asst Professor.

Comment