Acidic rock a speed bump for I-99 construction
When construction crews unearthed large deposits of the mineral pyrite during construction of Interstate-99 in Central Pennsylvania, the discovery set back completion of the road several years and inflated the cost by millions of dollars. The personal and emotional cost felt even greater to residents of the area, who saw well water go bad and the value of their homes plunge. Reporter Grace Muller explores what happened on Skytop Mountain and whether much of the damage could have been prevented.
The $100 million mistake on Skytop Mountain
The water ran red. That's when workers at PennDot realized the scope of the problem.
The Pennsylvania Department of Transportation heard about it from workers at the Department of Environmental Protection. A few had noticed rusty-colored water on the side of the road as they drove to work.
Around the same time, neighbors to the project suspected there was a problem too, when water in the creek turned red. They didn't know what to think when they heard it was from an oil spill up on the highway.
Stopping the flow of red water was only the first step of the 100-million dollar clean up on I-99.
I-99 is a road that links Interstate highways 80 and 76 in the heart of Pennsylvania, though some people who live in the area say the road is the link that bridges Philadelphia and Pittsburgh to Penn State football.
For people living in the area, the road has been both a great thing -- getting rid of traffic in the neighborhood -- and a nightmare. They can't say yet if it has been worth it.
Construction of the highway had its share of routine problems. Then it hit a major obstacle -- a rock called pyrite.
It's common to find the rock in Pennsylvania. When workers first found it, people at PennDot thought the pyrite was garden-variety.
"Did it turn out to be worse than that? Yeah, it sure did," retired PennDot district executive George Khoury said.
Pyrite is best known for one form, Fool's Gold. People used to mine it thinking they would make a fortune. In this case, on Skytop Mountain ten miles outside of State College, PennDot found a stadium-sized pile of Fool's Gold's cousin, another kind of iron sulfide, and lost a fortune.
Video: Country store owner Frank Hartranft keeps a piece of Skytop Mountain pyrite by the cash register to show customers the rock that caused so many problems up the road.
This type of pyrite is no problem when it stays underground. Rain seeps through the rock, creating small amounts of sulfuric acid over hundreds of thousands of years. The pyrite in Skytop Mountain only became a problem when contractors exposed tons of it over two years, in 2002 and 2003, while building I-99.
The fool's gold that you've seen before, in kids' geology kits or funky old jewelry, breaks off in big chucks. The type of pyrite that plagues I-99 is laced through the sandstone, giving it more surface area for water to hit.
If pieces of fool's gold are like coffee beans, the pyrite in Skytop had the consistency of finely ground coffee. If you run hot water over coffee beans, you'll get some coffee-flavored hot water. When water filters through ground coffee, or iron pyrite, that's when you get the strong stuff.
The pyrite in Skytop "was stronger than anything anyone had found before," Khoury said.
The sulfuric acid, in turn, leeches other minerals out of rocks in the mountain and into the water. In the area around I-99, tests found unusually high levels of lead, manganese, iron and aluminum.
Hard to sell to taxpayers
Video: Penn State geologist David "Duff" Gold consulted on the I-99 project. He wishes now that he'd been called in sooner.
The Skytop section of I-99 is four lanes and two and a half miles long. PennDot accepted an initial construction bid from a company named HRI, Inc. for around $39 million.
For the completed project, road and bridge building costs fell in close to that, at $44 million, according to Marlaine Fannin, a PennDot community relations coordinator. Efforts to fix the problems caused by construction soared to more than twice the price of building the road. They are now in the $100 million range.
People have known that there was pyrite in Bald Eagle Ridge for decades, Penn State geologist Duff Gold said. They just didn't know how much.
A Pittsburgh engineering firm, American Geotechnical and Evironmental Services, took the core samples for the project in 1998. They took samples of the rock by drilling straight down and then horizontally into the mountain. Gold said that the firm used the wrong sampling strategy.
Because of the way the mountain formed millions of years ago, the layers of pyritic rock in Bald Eagle Ridge were vertical, not horizontal. A few steps to one side or the other and the core sample taken from above could miss the bulk of the pyrite. That's what happened on Skytop.
Skytop's pyrite has been described numerous times by people involved in the project as a particularly "wicked" type.
It's a "totally unique formation ... found nowhere else in the world," PennDot's retired district executive Khoury said.
When contractors started digging into the hill, they had no idea the amount of pyrite underneath. Two percent sulfur is the highest level of sulfur in the core samples. Gold says the amount of pyrite they found in Skytop is closer to five percent.
A five percent ore body is a high enough percentage to mine the area, if anyone wanted to mine pyrite for its sulfur.
How they fixed it
Timeline: PennDot has tried to fix the problems caused by pyritic rock in I-99 since 2002.
Water hitting the newly exposed pyrite makes sulfuric acid that seeps into the ground. The minerals the acid released has made the water borderline undrinkable for some people living in the area. Vera Carson is one of them.
Roy and Vera Carson built their house 55 years ago, near the intersection of state highways 322 and 550. Roy's family owned the land and his brother had a service station there. Everyone called the intersection Carson's Corner.
Living on Carson's Corner put Vera in a unique position to watch PennDot's activity on the two highways. Almost a decade ago, she started her watch on a new section of 322, which eventually became I-99.
Sitting in her living room recently, Vera glances up as a dump truck drives by. Through the window, it looks almost as tall as the house. Vera pauses her sentence, distracted as her eyes follow the truck down the road.
"I've got to nose [around] to see what they're doing," Vera said.
She has nosed around so much that she was told she couldn't walk around a new water treatment area without a hardhat. So Vera borrowed one.
Water drives Vera's investigation: her water, the noise of dump trucks running past her house and the dust billowing down the road after them.
The 80-year old now has a handwritten list sitting on her kitchen counter of names and phone numbers she's compiled of people to call: PennDot's field office, the Department of Environmental Protection, and I-99's primary contractor HRI Inc.
Vera first noticed something strange happening with the I-99 construction when the huge trucks started taking loads out of the construction site after dark.
"They started hauling dirt out of here at night. And so I call and ask them 'well, why do you haul this dirt at night?' They had to cure over winter," Vera said. "I never heard tell of curing dirt over winter. That told me something was going on wrong, so that's when I started checking into it."
Her well water was fine for more than 50 years. Now, she doesn't know if she and her husband will be able to sell their house when they get older. She doesn't know if she will ever be able to open her windows on a summer night again, without dust from construction blowing in.
Jay Siewers lives down the road from Vera. He's lived in Matternville for 32 years, long enough for neighbors to call him the mayor of Matternville. People there know him as Hooter.
Hooter's tiny village boasts a former stagecoach station, a stop on the Underground Railroad and a creek that runs through their yards, down the hill from I-99.
These days, residents of Matternville can also boast that they live 500 feet away from the most contaminated water in the I-99 project.
The tiny brook trout in their creek have "gone belly up," Siewers said.
PennDot ripped out the old stagecoach road to dig the containment pool. The trees that protected the village from road noise and wind were chopped down, with the promise of being replanted in the future.
"It would take a couple of generations to restore all that," Hooter said. "It could be done, but they took away what we had, for the ones that were living here."
The containment pond looks benign, a pool of water surrounded by dirt.
Hooter asked for a show of hands one night at a public meeting, back when there still were meetings about the problems with the highway. He asked if anyone would take a bath in the containment pool. No one raised their hand.
The water in the containment pools has alternately had high levels of lead, iron, aluminum and manganese. The PH of the water hovers around 3, as acidic as vinegar, before treatment. Pure water has a PH of 7.
"So then I put my hand up and said, well, apparently, this is what I'm doing," Hooter said.
Unlike neighbors, that use well water, Hooter's water came from an artesian spring that shares an aquifer with the containment pool. Hooter says sharing the aquifer with it is like taking a bath and drinking the water out of the containment pool.
"I remember the one time, the water got so bad," Hooter said. Skelly & Loy, an independent engineering firm that does the water sampling, "checked it and there was a lot of lead in there. And that was the scary point there."
That's when Hooter started getting bottled water.
Bad well water is not uncommon in Pennsylvania. In a study done by Penn State, 40 percent of the wells tested were over the state's safe-drinking-water standards for at least one contaminant. Many of the people living there didn't know they were drinking bad water.
In some areas, people blame new construction for problems with their water they've actually had for years. It doesn't seem like that is the case for most living in the area around I-99. Test results from the Pennsylvania Department of Environmental Protection show clean water before construction started in the area.
HRI pays to have reverse osmosis water treatment machines installed in houses if the well tests meet the guidelines set by the PA Department of Environmental Protection and Skelly & Loy.
The water has to consistently go above safe water drinking guidelines for compounds related to the rocks on Skytop. Hooter's test results bounce up and down between each testing, so he's never met the guidelines for a water treatment system.
"I don't want to buy [a reverse osmosis system]. My water was fine before," Hooter said.
While residents' drinking water is in limbo, fish are fine swimming downstream from the I-99 project.
"You can't pee in one end of the pool"
Video: Longtime fly fisher Robin Schulze says Spruce Creek is lucky to have escaped problems from I-99 construction upstream.
Buffalo Run is a tributary of famous Spruce Creek, notably fished by President Jimmy Carter. The stream's high alkaline content helped buffer the acid runoff. The Fish & Boat Commission only has one report of a fish kill in the area since the problems on Skytop started.
Dave Spotts, from the Pennsylvania Fish & Boat Commission, said that without PennDot's quick response, the acid runoff could have put fish in danger in Buffalo Run.
Fly fisher Robin Schulze agreed. "Something that happens in the watershed often makes its way into the waters you care about."
Schulze said fisherman lucked out -- this time.