Waste, Wind, and Water: GSOC Field Trip to Eastern Columbia Gorge
by Janet Rasmussen
On June 19th and 20th, 2009, Dave Olcott led GSOC members on a field trip to the eastern end of the Columbia Gorge to tour a waste facility, wind farms, and cherry orchards.
We paused after exiting I-84 at Phillip Canyon to be certain all cars made it this far. Car caravan field trips can be a real challenge, but cell phones helped us keep in touch, at least when service was available. Jan rode with Dave in the lead car and kept us moving along and staying together.
This large rounded mound, visible from about Milepost 123 on the I-84 route through the Gorge, is an expansion bar deposited by the Ice Age Floods (also known as Bretz Floods and Missoula Floods). The massive floods, which overtopped the Gorge on the south side in several places, rushed through the narrows upstream, but when the waters reached this widened part of the Gorge and flowed up the side canyon, the current slowed and consequently dropped an enormous load of boulders and gravel.
Barge traffic heading downstream on the Columbia River, as seen from our first stop.
Trip leader Dave Olcott, left, addresses the group as we view more massive flood deposits in Phillipi Canyon.
The road up the canyon took us past these pillars of "biscuit basalt", which have horizontal as well as vertical cleavage. This basalt is from the Priest Rapids member of the Wanapum Basalt (middle Miocene). We were fortunate to have Columbia River basalt expert Bev Vogt with us on the trip.
As we continued through wheat farming country, heading south on Phillipi Canyon Road, we stopped to look at these glacial erratic boulders, mostly granites. They were likely rafted to the area in icebergs during the Ice Age Floods 10-12,000 years ago. Dave stands atop one of the boulders, while Sara looks on. He said these boulders were likely found throughout the area, but moved to the edge of the field to get them out of the way of farm equipment.
Beautiful wheat country on the top of this plateau. This winter wheat is farmed without irrigation, using specific methods to conserve soil and water in this dry country.
We turned onto Blalock Canyon Road, and drove east until we entered Alkali Canyon, for a tour of the Columbia Ridge Landfill. The landfill takes 40% of Seattle's household waste via train, and 85% of Portland's waste via truck. Gilliam County, population around 2000, was happy to have the landfill sited here, where it provides many jobs and good tax income for the local economy. The operators make an effort to manage the landfill sustainably. Water is recycled through the waste dumps to encourage bacterial decomposition without wasting the little water that falls on this dry country.
The facility also owns 12,000 adjacent acres, which are leased to Pacific Power for a wind farm.
We piled onto a tour bus to take a closer look.
Containers of compacted trash are decoupled from trucks and lifted on ramps to spill their contents, while enormous caterpillar trucks compress the trash into the ground. Each day's trash is covered with a foot of soil and fences collect the ubiquitous blowing plastic bags. Unfortunately, there are escapees. Try to avoid using plastic bags!
Currently, methane is pumped from within the landfill and burned in a single flare, but within a few months, this 6.4 megawatt generating facility will burn the methane and provide power for operations.
At the end of our tour, geologist/bus driver Joe Kephart, drove us up to an outcrop of gravels, over silty deposits, on top of Rattlesnake Ridge ash beds. The carapace of an extinct species of turtle was found above the ash beds and is exhibited in the office of the facility.
We left the waste facility to return to the Interstate. Along the way, we stopped to view these massive delta deposits from the Ice Age Floods. Doug stands here for scale.
We had a brief rest stop in beautiful Arlington, before continuing on to Rufus. There we met Sandy Macnab, who rode with us for the next portion of the trip.
At our next stop, south of Rufus, I had to get a photo of these beautiful horizontal ridges on the hillsides that we are all so familiar with. They are partly a geological phenomenon of slumping rocky hillslopes, emphasized by game and livestock trails.
Sandy told us how several flash floods had shot boulders through the culverts into the town of Rufus. Metal fences in the canyons above the culverts have trapped some of the rocky debris, but they are still at risk for devastating floods. See how the canyon below a culvert under the road has been eroded by the hydraulic power from above.
Sandy Macnab, Sherman County Extension Agent, explained some of the conservation measures used to preserve soil in dry wheat farming. From the wheatfields we could see wind turbines in all directions, like kinetic sculptures, rotating steadily in the breeze. We visited Portland General Electric's Biglow Canyon Wind Farm and Iberdrola's Klondike Wind Farm.
Wind energy is neat and the windmills are beautiful structures, in my opinion. But there are downsides. They do make a little noise, and they all have flashing red lights on top, which can be disturbing to rural residents accustomed to nothing but starlight. And then there are the birds and bats. Every year people do counts of dead birds under windmills to assess this risk.
According to a recent study, there are 0.0-2.0 bird fatalities per turbine per year and 0.0-47.5 bat fatalities per turbine per year. (Jana S. and Pogacnik, M., 2008. The impacts of wind farms on animal species. Acta Veterinaria-Beograd 58:615-632) We'll examine the issue of bird:blade contact in the puzzler.
We saw wind turbines under construction, and many more in use than we had suspected. It seems like every time we drive to Eastern Oregon, there are more to be seen, and always the parts are being moved along the Interstate by trucks heading east.
At Iberdrola's facility, Jackie stands within the base of a giant turbine blade.
A view of a wind turbine from between two blades lying on the ground.
Doug and I stand before a nacelle on the ground. This is the aerodynamically shaped housing for the gears and drivetrain at the top of the wind turbine, to which the three blades are attached. They are about the size of a motor home. Hmm, if they only had windows, wouldn't that be a great place to live? Long way to carry the groceries, though...
The puzzler: Let's assess the risk of a bird hitting or being hit by a windmill blade while flying through the circular area described by the turning blades. If we estimate the area of the circle taken up by blades at 5%, then every bird who is simply not looking where it's going, perhaps texting while flying, has a 5% chance of striking a blade while flying through. Now let's evaluate the additional risk of being hit by a moving blade. First, I'll list some assumptions to make the problem easier. We'll assume that:
The windmill is a 2-dimensional structure, the blades are straight, and the center point is inconsequential.
We won't consider the area of the bird, only its length and velocity.
The question has two parts: 1) How fast (in mph) are the blade tips turning? We estimated the risk of a bird hitting a stationary blade to be about 5%. 2) What is the additional risk, to the nearest percent, of a 12" long bird, flying at 30 mph, being hit by a moving blade while flying through the area described by the blades of the windmill?
According to a handout from PGE's Biglow Canyon Wind Farm, the three rotors turn clockwise at 14.4 rpm with a rotor diameter of 269 feet. Hint: to answer these questions, you will need to calculate the circumference and area of a circle and do some unit conversions. It might be helpful to make a simple sketch of the problem. If you find this exercise frustrating, please be aware that it took Doug (a professional mathematician) and I many hours to construct the problem and argue out the details, but at last we agreed and came to the same answers. Of course it takes me twice as long and I throw in all sorts of circuitous and redundant steps and can't remember how many feet in a mile, etc.
The first correct answer to both questions wins choice of lunch or dinner with the editor or an exciting gift package of locally produced goods. Honorable mention to all who can answer the first or both questions correctly!
We returned to I-84 via Fulton Canyon, where we made a stop.
On the north side of the Columbia Gorge, erosion from the Ice Age Floods carved terraces and sheared off the ends of ridges about halfway up the canyon wall.
I didn't know that a portion of the Oregon Trail can be seen here at the mouth of Fulton Canyon. Bart is walking up the old ruts, which were used in later years for cattle drives.
At last we returned to The Dalles, where most of us stayed at The Dalles Inn. Dusty and weary, we checked in, and then regrouped an hour or so later for a walk to The Mint, where we planned to have dinner and a wine tasting. The original building was constructed in 1864 of hand-hewn local stone for the purpose of minting coins from Canyon City gold diggings. By the time the building was completed, the gold was dwindling, and eventually the building changed hands several times. Now it houses Erin Glenn's Winery and tasting rooms. We were treated to a special tasting of four wines in the stone and brick walled cellar, surrounded by oak wine casks, dimly lit with candles perched on small ledges in the stone walls. We also were given a salad and appetizers, and chose our dinners from a menu of small plate dishes. Quite a few came away with bottles of wine. We were treated to an oral history of the building while local musicians played above.
Taylor pours a red wine.
We met up the following day at the Safeway parking lot, to begin our tour of cherry orchards and more geology.
We drove to Sirosis Park on a hill in The Dalles, overlooking the Gorge. Today, our local host was Tom Bailey of Orchard View Farms. In the upper left, an arrow points to the land once owned by his great grandparents in the 1880's. He told us an old family story about the place that exemplifies the complicated and fragile hydrology of this region.
While the father of the family was away for an extended period, the two young boys were responsible for carrying water from a 35-foot-deep hand-dug well. Water collected slowly in the stone bottom of the well, so that they had to repeatedly drop and haul up a bucket to fill, cup by cup, another bucket for water. They decided to make the bottom of the well a little deeper so that they would only have to drop the bucket once to fill it. They took turns lowering one another into the well, and working with picks until they had hammered away another foot of basalt rock, and made a deeper collection pool for water. This took them a couple of weeks. But when they came to collect water one morning, the well was dry. All the water was now draining away through a fracture now exposed in the basalt floor of the well. The homestead had to be abandoned.
Tom Bailey tells us his family story, while Susy and Arthur listen.
As we drove back down through town, Tom pointed out several homes in the hills that once stood above the level of the sidewalk. They are unfortunately located on the rotating block of an active landslide, and now are beneath their former level. This house has elevated its driveway and garage. Another house is having a new foundation put in to lift it up. But those are just stopgap measures. We were a little surprised that building lots are still for sale in the area.
Near the top of the fault block are gravelly deposits of the Chenoweth Formation.
We stopped coming down a long hill to look at this outcrop of a Cascadian lahar, or pyroclastic flow. Blocks of volcanic rock are caught in the hardened ash. Clay and Barbara Kelleher's grandson joined the Geological Society field trip. Here with his hand sample he stands for scale beneath the outcrop. What are the odds of young Bailey developing an interest in the geological sciences?
Jackie holds a chunk of ash with the imprint of a burned twig in it. These were pretty common here.
The beautiful sweet cherries of the region are just beginning to ripen.
Our field trip continued with several stops at cherry orchards, where we were just beginning to learn about the unique challenges of growing cherries in this region. Ongoing research on irrigation and water conservation measures, as well as innovative methods of non-chemical preservation of ripe cherries for shipping, have optimized the production of large, delicious sweet cherries. The orchards are planted with different varieties at elevations ranging from 100 to 1800 feet so that fruit is ripening continuously over a longer season.
As we caravaned along on winding hilly two lane road, Doug suddenly choked on an apple. I had to stop abruptly in the middle of the road. He was able to clear his airway, but a piece of apple remained painfully lodged in his esophagus so that he couldn't swallow. Bev, who was riding with us, called the lead car. Jan hopped out and advised every driver to stay in formation. Tom, still riding with Dave in the lead car, led us directly to the emergency room at the hospital in The Dalles.
The rest of the folks continued on the trip. After awhile, Bev and Bart were picked up from the waiting room so that they could continue the trip and get an alternate ride home. Doug and I languished in the ER for 4 hours, the place was jam-packed with more coming in. After a dose of medication, Doug was able to swallow small sips of water, but they were unwilling to perform a procedure to remove it until the following day, saying that the problem would likely resolve itself. We finally left and headed for home. As we entered Portland, the apple finally went down.
We were sorry to miss the end of the trip, but I was able to get some questions answered about the cherry growing when we met the group again for Clay's geological interpretive hike of Silver Falls State Park in July. Doug recovered in a few days from his experience, but has been eating cherries instead of apples.
