TIOGA, ND (KFYR/CNN) – Oil officials in North Dakota say a pipeline spill has grown far beyond original estimations made two weeks ago.
The "Tesoro" leak was first reported to be about 750 barrels worth – that figure skyrocketed on Friday to more than 20,000 barrels.
A local water supply official explained why the size of the spill jumped so much.
"It wasn't s surface release, and so until they did geo-probe borings and put in monitoring wells, they did not have the full extent determined," said Dennis Fewless of the North Dakota Water Quality Division.
Water safety experts say the spill could have been even worse, but a layer of clay below the spill is keeping the oil from seeping into any ground or surface water.
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