Sioux City Journal

Drilling shows aquifer lies beneath refinery site

Geologist: Till protects aquifer from surface spills

By Michele Linck Journal staff writer | Posted: Wednesday, August 06, 2008

ELK POINT, S.D. -- The Lower Vermillion-Missouri Aquifer underlies all or most of the Union County site where a Texas company wants to build an oil refinery, but a South Dakota state geologist said that doesn't worry him.

Derric Iles is part of a team that has been drilling test holes for permanent monitoring wells in the area where Hyperion Refining hopes to build a 400,000-barrel-a-day refinery and energy center. Iles said the team has found what he called "a protective layer of till" -- a glacial deposit of fine clays and silts -- lies between the aquifer and the land surface. He said till is highly impermeable, making it difficult for substances to leak through it.

"For that reason, I don't view activity at the land surface, such as the proposed energy center, as posing a threat to the lower aquifer," Iles said. "That's just my opinion. We have to do the drilling and install the permanent ground water monitors."

He said the monitors will provide scientific data showing whether his opinion is warranted.

The drilling team discovered there is enough alluvium along Brule Creek upstream of the refinery site for shallow monitoring wells, but drilling remains to be done downstream, Iles said.

The geologists were surprised to find that the aquifer apparently does not reach as far east toward the creek as old maps show, he said.

The creek runs just east of the eastern edge of the nearly 4,000-acre site for the proposed refinery, about seven miles north of Elk Point. Nearby residents have cited pollution of the aquifer and creek among reasons they oppose the $10 billion project.

Drilling, which started in mid-July but was interrupted by an equipment breakdown, will continue for another week as the team drills deep test holes to better define the aquifer and sinks at least three monitors more than 200 feet deep.

The state Department of Environment and Natural Resources is reviewing Hyperion's air-quality permit application. Project executive Preston Phillips told the Journal last month the company expects the application to be ready for the required 30-day public comment period later this summer, but DENR spokesman Kim Smith said department engineers were not ready to predict when it would be ready.

Story Comments

UnCoGal wrote on Aug 7, 2008 2:02 PM:

" Now finally there is talk about an independent, unbiased group doing an Environmental Impact Study! The EIS should have been done before the P&Z vote, before the Commissioners vote, and long before the public vote. With that information each group could have made an informed decision, rather that voting on the "green" statements from Hyperion. Better late than never. The EIS is the law in SD, so we will see if it gets obeyed or by-passed! "

UnCoGal wrote on Aug 7, 2008 1:56 PM:

" Name calling proves nothing! Thank heavens they are going to put in perimeter groundwater monitoring wells. Groundwater is often polluted with petroleum products near refineries. Check out Rosemount, MN. The contaminating leak went into the bedrock. Safe? No, the bedrock cracked and the petroleum went into the water source! "

DakotaCowboy wrote on Aug 6, 2008 3:36 PM:

" dwmjb. Lets see is that for Dumb Witted Mindless Jerk Blowhard? Look around you, not all water comes from a bottle. I am sure you wouldn't be able to find it, but for starters, where is this research of yours? "

Bull Rider wrote on Aug 6, 2008 2:27 PM:

" If anyone hasn't looked around, the state of Montana has 2 oil refineries exactly like what will be built here, only this one will be newer, safer, cleaner, more efficient. Those 2 in Montana a state which has a little more environmental awareness than sandy dusty old South Dakota, were just fine with them building and operating there. They are cooled by the Yellowstone River which if you look at where it flows...eventually right past Vermillion, via the Missouri River. Point being, they have had zero issues with it. They have enjoyed the economic impact. They would gladly take another one if they were chosen again. "

dmwjb wrote on Aug 6, 2008 12:56 PM:

" Dakota Cowboy: your commments are ignorant and just plain stupid. Sure, let's just go ahead and put in a refinery with no research and study on how it might affect our air and water. How irresponsible. And for you to call people who are concerned about these potential affects as using "scare tactics" shows your complete and total ignorance. "