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Sustainable Waste Management Dialogue of Civilizations
Scott Hershey (on the right) is a senior structural engineering student on the Sustainable Waste Management Dialogue of Civilization with Professor Annalisa Onnis-Hayden. He just graduated after four years and is currently finishing out his general electives. After this, he plans to live in Colorado for the summer working as a whitewater rafting guide and then hike in all the national parks. Eventually, his goal is to work for a timber-engineering firm designing large timber or CLT (cross laminated timber) buildings currently nonexistent in the United States. He is interested in free food around campus, off-roading, working out, and being outside.
Sustainable Waste Management Dialogue of Civilizations
Four weeks ago I took a big step in my life, I started a blog. Now to many, this wouldn’t seem like much, but I had never done such a thing before. I’d never journaled, never scrapbooked, rarely put photos on Facebook even though I love to take them, and truly hated the thought of writing a blog. I started my trip to Sardinia on this Dialogue of Civilization by writing a (required) post about my thoughts and expectations of what this trip would be about. Somehow I got hooked on the idea of documenting my trip, not just in pictures that I think are worth over a thousand words, but in words as well; my thoughts instead of just visuals. I knew I wanted to go into engineering in elementary school, partially because I loved math, but also because I was repulsed by the idea of a writing intensive career. Now, one of the last things I do in my undergraduate engineering career is volunteer to write a COE blog post. Go figure.
So what am I doing here? Where am I? Can I still get Chicken Lou’s or a Dunkin Donuts iced coffee? Sadly the answer to the last question is “no” but I’ve found equivalent vices. But really, as someone who did their main civil courses focusing in structural engineering and construction management, why did I choose to go to an island in the middle of the Mediterranean to study environmental engineering? We have the obvious answer of, why not go to a place whose Google Image search results show white sand beaches nestled in covert coves with turquoise water as far as the eye can see; but there’s more.
The main focus of this dialogue is sustainable waste management and that doesn’t just mean promoting greater recycling percentages. This topic has a broad range of specific applications from mining waste remediation to incineration plant processes. Now this is really what I’m into because it touches on all fields of engineering. I was always that kid who would watch the trash trucks do their collection because, as many would disagree with me, it was interesting. What happened to that old lawnmower you took to the dump when it stopped working? I went there and took it to try to fix it (and was generally unsuccessful in my youth). The other topic that piqued my interest was the mining waste remediation. Over the past few years I’ve been spending my summers in Colorado, a former gold rush state, and it seems like wherever you go, you can see a pile of mine tailings (the unwanted crushed stone) or a highly acidic yet beautifully turquoise tailings pond. What are we doing with these contaminants that crowd the beautiful landscapes?
Our classes have been answering the exact questions I’ve been asking myself for years and although this field isn’t my primary focus, it has changed the way I live my day-to-day life. Coming to Sardinia to study waste management is a great choice because Italy is just average within the European Union in regards to their waste policies. They aren’t Sweden (who only landfills 0.7% of their total trash) but they also aren’t Bulgaria (who landfills 100% of all their waste). Italy’s rates are around 50%, but that number is going down with increased recycling and incineration rates.
As an American you say “Incineration! That can’t be good!” and this is one of the main differences between the EU and the US. It’s similar to the debate of gasoline vs. diesel. As a self-proclaimed “gearhead”, I am a supporter of the cleaner emissions of diesel vehicles (regardless of higher somewhat higher NOx emissions that seems to be a focus point of the debate…) and it seems the EU is as well. Just like this debate, the landfill vs. incinerate debate is about choosing the lesser of two evils. Do we potentially pollute our water supplies, air, and land with the eyesore that is a landfill or do we burn the waste instead? With incineration we can produce energy for the grid or use the heat for district heating similar to New York City’s district steam. Another advantage is waste reduction factor. By incinerating our waste, scrubbing the emissions, and recovering the incombustible metals, we are saving precious land, preventing nonrenewable resources from sitting in a landfill, and creating a safer environment for all. Our course was focused on this type of material but also included site visits to solidify our knowledge.
Sardinia was once a mining hub for Europe due to its large amount of natural resources, but also because of its geographic advantage for trade. We have done site visits to historic landmarks such as Porto Flavia, an old mining distribution center on the western coast used to load ships with mining ore to be transported to refining areas. Just like Colorado, traveling around areas of mining activity you can see the large tailings piles. Some have been repurposed such as in the city of Iglesias where a tailings pile was used as the base for a soccer field (spoiler alert: terrible idea). High levels of lead and other heavy metals have been found in the populations of the area that can be attributed to this mining activity. Instead of building on top of them, researchers at the University of Cagliari have been looking into phytoremediation techniques. Other than being a big word that makes you sound smart, phytoremediation is proving to be a cost effective system and environmentally sustainable technique for removing or capturing heavy metals from the soil.
So what is phytoremediation and how does it work? Phytoremediation is the process of using plants such as Douglas Fir trees or Alfalfa plants to uptake the contaminants from the ground and hold them within the plant. This system has been shown to take contaminants such as lead at concentrations of over 5,000 mg/kg of soil down to the allowable threshold of 100 mg/kg. The species of plant used is determined based on the application. Deep rooted species such as Douglas Fir or Willow trees can be used to stabilize areas with deep contaminants or contain water table contaminant plumes. Smaller, faster growing plants such as Alfalfa or the Mastic tree can be used to stabilize or to completely remove toxins by moving the toxins to their shoots, stems, and leaves. These plants can then be removed and disposed of, completely decontaminating the area. It’s systems like this that I never would have learned had I taken classes on campus.
There was a large cultural aspect to the trip as well. Other than just learning about how they move trash around here, we got to see the island in a way most tourists wouldn’t. Our Professor, Annalisa Onnis-Hayden, is a native to the island and did most of her studies at the University of Cagliari, where we are currently studying. Her PhD advisor has given us talks and shown us the labs but has also come to dinner with us. In the first few days she was even nice enough to tell a little white lie and say I could pass for an Italian based on my clothing choices. We’ve gone to the beaches seen in the Google searches, made pasta by hand in the traditional Sardinian fashion, and hiked into the deepest canyon in Europe.
|Gorropu Canyon –
Tiny Human for Scale
|Native Sardinian or Northeastern Civil Engineering Student?|
I’ve had enough charcuterie and seafood to feed a small army it seems, and have even tried horse meat. If you’re wondering, it’s similar to beef, a little leaner, and a little sweeter. I’ve explored underground caves filled with massive limestone stalactites and stalagmites and the geology nerd in me has taken too many pictures of angular unconformities (shoutout to Prof. Richard Bailey). I’ve found my Chicken Lou’s equivalent, the only place in the city to serve a real, greasy, American burger but have yet to find iced coffee here.
|Neptune’s Grotto with
Stalactites and Limestone
Columns in the Background
|Angular Unconformities Galore!||Charcuterie Board|
Was I thrilled to be going back to classes after walking for graduation? Not at all to be honest. At this point though, four weeks after getting to Sardinia, I don’t regret how my last weeks of college have played out. I’ve met some incredible people, eaten like a king for weeks, and lived the life of an Italian. Annalisa told us on the first day that, just as she did in France in her college years, someone here has to find their spouse when they come here. Sadly I didn’t find my Italian wife yet, but I still have one week to go. Wish me luck.