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Prelab 9 – Chemistry Alexis Clemons ISP 203L

Answer the questions on this document. Highlight your answers by changing the font color. Answer the following questions on your own and in your own words. Cite your sources when applicable. Save as a PDF prior to submitting on D2L.

Part 1 – The good the bad and the ugly Walking through campus on a beautiful spring morning you notice a strip of grass that brown, brittle, and dying. As the newly elected president of the school’s environmental club you vow the determine the cause and to prevent this from happening in the future. Your first step is to consult with the school’s grounds manager, April Liu. It turns out that April has been trying to keep this from happening each spring. “It’s because of all the salt we use to keep the sidewalks from freezing over all winter. We have to keep students safe as they travel between classes.” “Isn’t there a limit to how much salt you can use,” you ask April. “Not that I know of,” replies April. You decide to do some research on the subject. A quick internet search reveals that chloride standards exist for surface waters like rivers and lakes, but there seem to be no standards for the amount of salt that gets applied each winter and no one seems to be keeping track of the concentrations that are accumulating in the ground. You decide, as an environmental club, to set up an experiment to test the effect of different salt concentrations on the growth and germination of plants to help you establish a chloride standard.

BACKGROUND – Road Salt Salt is applied for safety reasons to impervious surfaces such as roads, parking lots, and sidewalks as an anti-icing or deicing agent during winter months. In the United States, use of sodium chloride (NaCl) based road salt has increased along with the increase in urban impervious land cover. There has also been a corresponding increase in chloride concentrations in rivers across the northern U.S., almost doubling average concentrations from 1990 to 2011 (Corsi et al. 2015). Although standards exist for chloride concentrations in surface waters there are no standards for terrestrial chloride concentrations that can impact germination and growth of vegetation. [1] Steven R. Corsi, Laura A. De Cicco, Michelle A. Lutz, Robert M. Hirsch, River chloride trends in snow-affected urban watersheds: increasing concentrations outpace urban growth rate and are common among all seasons, Science of The Total Environment, Volume 508, 1 March 2015, Pages 488-497, ISSN 0048-9697, http://dx.doi.org/10.1016/j.scitotenv.2014.12.012

BACKGROUND - Standards Read “A Brief Introduction to Standards” by Lawrence Busch

BACKGROUND – Bioassay* * Adapted from (http://ei.cornell.edu/toxicology/bioassays/lettuce/) Bioassays test for chemical toxicity by observing the effect different concentrations have on living organisms or tissue. Buttercrunch lettuce (Lactuca sativa var. Buttercrunch) seeds are a recommended species for bioassays by the EPA due to their ease of upkeep, rapid growth, and low expense. Additionally, both germination rate and radicle length can be used as response variables to the effect of various chloride concentrations.

PRELAB QUESTIONS – Answer in your OWN words. Refer to “A Brief Introduction to Standards” for questions 1-3. 1. What are technical standards? Technical standards are an established norm or requirement in regards to specific processes which ensures the processes are being used correctly. It’s also used as a set of data for comparative means in regards for other data. 2. How are standards developed? Standards are developed based upon a need for them and once a need for a standard is established, the development of the standard is underway. 3. What are some implications (economic, social, political) of implementing certain technical standards? Economic implications are the value of currency, social implications are common courtesy, and political implications are creating established governments 4. As a student at MSU you have a stake in chloride standards. Describe three other stakeholders that would likely be interested in chloride standards. MSU is a stakeholder because they want students to be healthy, the city of East Lansing is a stakeholder because they want citizens to be healthy so they can contribute to the local economy, and Environmental groups would be a stakeholder because they want to make sure the standards are upheld so that water running off into watersheds don’t damage the ecosystems. 5. As a student at MSU how do you perceive 1) the current road salt application practices on campus and 2) the value of maintaining healthy vegetation along the sidewalks The roads are close to being clear, I believe that if we could reduce the amount of salt on the roads there would be little impact on driving. As long as drivers be careful there shouldn’t be an issue with light snow on the surface. The

value of maintaining healthy vegetation is great. The better the sideways look the greater impression you have on students. 6. Be prepared to discuss, in detail, your project proposal with your classmates....