‘2009 EIA of Uma Oya foresaw possible groundwater drawdown’

The experts’ panel that compiled the Environmental Impact Assessment (EIA) in 2009 for the Uma Oya Multipurpose Development Project (UOMDP) today stressed that the EIA had clearly indicated the possibility of a draw down of groundwater through weaker zones into the tunnel, affecting domestic and irrigation activities in the surrounding.

Appearing before the media after seven years amidst allegations levelled on the EIA team, the experts yesterday rejected all allegations and stated that the EIA process had gone through the standard procedure.

The panel of experts headed by Senior Professor in Zoology of the University of Sri Jayewardenepura Ms. Swarna Piyasiri and Senior Professor in Engineering of University of Peradeniya K.D.W.Nandalal comprised 19 consultants including a hydro geologist, tunnel engineer, soil scientist, water quality expert, archaeologist, irrigation engineer, fauna and flora geologists, agronomist, infrastructure engineer, resettlement expert and an electrical engineer.

Senior Professor Swarna Piyasiri said the EIA team had recommended to the Central Environment Authority (CEA) to continuously monitor groundwater level fluctuations in the area around tunnel trace, especially along major fracture zones connected to the tunnel, during construction and operational stages.

“The EIA had identified and expected possible lowering of water table during the construction phase with the geological structural maps available by that time. In such instances, sealing of water leaks through proper grouting is necessary prior to further drilling of the tunnel,” she said.

Responding to questions as to who should take responsibility for the environmental, social and geological problems occurred in the project surrounding, Prof. Piyasiri emphasized that the responsibility lay on the EIA team only in planning and compiling the EIA which was issued in three volumes.

“With the approval of the UOMDP by the CEA, the implementation phase of the project commenced for which the involvement of the EIA team is beyond the purview according to the CEA’s terms. As per the terms, monitoring of the project’s activities is not mandatory for the EIA team,” she said.

She further said that the conditional approval letter of the CEA stated that the safety and emergency measures as well as monitoring plan of the project has to be followed by the Ministry of irrigation and Water Resources Management.

Senior Professor K.D.W.Nandalal stated that in any tunnel construction of underground mining operation, issues with the groundwater of the tunnel area can happen.

He said after grouting of fracture zones, groundwater flow towards tunnel area will gradually slow down with the rainfall and rise of water table could also be expected with the time.

“After proper lining and grouting, aquifer may recover but needs some time after the construction. This is a usual phenomenon,” he remarked. (Piyumi Fonseka)