ENVR EXERCISE Lab 3 Environmental Scene Investigation (ESI)

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1 Name: Overarching Theme for Labs The Texas Commission on Environmental Quality (TCEQ) is the principal environmental agency for Texas. Their mission is to support economic sustainability while protecting human and natural resources by monitoring and regulating environmental quality (e.g., clean air/water, proper waste management). With offices all over Texas, they are involved in a broad range of scientific studies and they partner with Homeland Security, FEMA, the Superfund Program, and Texas Parks and Wildlife. Throughout this semester, you will be acting as a TCEQ contractor reviewing a whole series of environmental questions, from toxic spills to disaster response. Consider these as realworld scenarios, because the situations you will be presented with can and do occur! ENVR EXERCISE Lab 3 Environmental Scene Investigation (ESI) SAFETY CONCERNS: Chemical splash goggles must be worn by everyone in the lab while chemicals are out and in use. Goggles and a sterilizing cabinet have been provided in the lab classroom. Safety glasses are not permitted as a substitute. Care should be taken to keep all lab materials away from the edge of the lab table where they could be knocked onto the floor and broken. Notify me immediately if glass breakage occurs. Students are not to clean up broken glass. Notify me immediately if a chemical spill occurs. Students are not to clean up chemical spills. Care should be taken to minimize inhaling chemical vapors by wafting. Care should be exercised when using hot plates to prevent burns if touched directly. Care should be exercised when using Iodine solution as it may stain clothing and skin. DO NOT taste any substances being tested. Dispose of all waste from chemical testing ONLY as directed by lab instructor. Overview This activity explores the concept and application of the scientific method. In order to distinguish between association and true cause-effect relationships, phenomena must be investigated using designed experiments and careful observations that can be repeated by others. Background Galveston has a history of devastating hurricanes. In 1900, Galveston was essentially obliterated by the hurricane, with a loss of life possible reaching 12,000. As this hurricane occurred before the official procedure of naming storms, it is commonly known as the Great Galveston Hurricane or, somewhat incorrectly, the Galveston Flood. Regardless of the name given to it, it stands as the worst natural disaster in U.S. history in terms of loss of life. Since that time, Galveston has suffered at least 14 other damaging hurricanes. In addition to, and often as a direct result of, destruction and loss of infrastructure, hurricanes promote disease from dead bodies, standing pools of water that provide homes for mosquitoes, injuries, improper sanitation with loss of power to allow flushing, boiling water, etc.

2 We will discuss the response to a hurricane scenario and its possible implications in this lab exercise. The Problem Galveston, 2011: A Category 4 storm, Hurricane LeRoy, makes landfall on Galveston Island on September 9 just west of Galveston College. Wind speeds in excess of 140 mph caused complete destruction of small residences and apartment complexes over a 20 block area from 53 rd to 45 th street, leveled several gas station canopies sparking massive fires, locally broke through the sea wall allowing 20-ft high storm surges to cross the island, and blew much of the college seemingly into nearby Lasker Park. The storm continued inland along a northwesterly track; the storm did not turn to the northeast until it passed west of the Dallas-Fort Worth metroplex. Damage to the city of Galveston was slightly less severe, with wind speeds under 131 mph, but was still widespread. Power outages were reported over 65% of the city, with flooding >1 foot covering 40% of the city. See noaa.gov for a more detailed report. In the wake of this hurricane, every resource is being mobilized to help preserve lives and respond to basic needs in the affected area. In the outskirts of the city, one of many hubs for dispersal of emergency goods, a number of railroad boxcars containing ingredients desperately needed to produce food products for the citizens of Galveston were brought in by FEMA, the Federal Emergency Management Agency. Unfortunately, after the train was moved to a side track, it was discovered that one or two of these railcars were damaged during the hurricane as evidenced by white powder found alongside the tracks. A logical conclusion is that if the contents of the railcar could leak out, then contamination could also enter the railcar and pollute the contents. Records indicate that the railcars contain various food ingredients: sugars, salt, flour, baking soda, baking powder, and corn starch. An additional railcar contains Plaster of Paris to be used in building repairs. As a scientific contractor with TCEQ, your assistance is needed in identifying what railcar(s) may have been compromised and potentially contaminated. The results you obtain will help FEMA agents decide which food ingredients (if any) to destroy and which may be safely used to help feed those in need. Materials: Vials of known rail car contents (1 set per group) Vial of unknown white powder (1 per group) Hand lens (max per group) Spatula (2 per group) Iodine solution (1 dropper bottle per group) Vinegar (1 dropper bottle per group) Dimple plate (1 per group) Grease Pencil (1 per group) Aluminum foil Hot plate (1 per group) Method: Observe and record your results on the Powder Analysis Chart for each identified powder. Remember you have a limited amount of each sample.don t waste any as you may need to run multiple or duplicate tests to confirm your results. Be careful to prevent cross-contamination of samples. Carefully clean the spatula (wash with water and dry with paper towel) before and after each use.

3 Visual Observation: Using a clean spatula, take a small amount (a few grams) of each identified powder and examine it with the hand lens. Draw what it looks like on the Powder Analysis Chart (e.g., Does it look like a fine powder or have specific crystal shapes? What is the appearance of the crystals?). Vinegar Test: With a grease pencil, label the rows of the dimple plate for each identified powder. Using a clean spatula, place a small amount (a few grams) of each identified powder in one dimple of the respective row of the dimple plate. Carefully add one or two drops of vinegar and watch for any reaction or change that might occur. Record your findings. Iodine Test: Using a clean spatula, place a small amount (a few grams) of each identified powder in one dimple of the respective row of the dimple plate. Carefully add one or two drops of iodine and watch for any reaction or change that might occur. Record your findings. Heat Test: Using a clean spatula, place a small amount (a few grams) of each identified powder on a piece of aluminum foil. Carefully place the foil on the hot plate to expose the powder to heat and watch for any reaction, change, or odor that might result. If perceptible smoke or a strong odor is given off by your heated sample, remove it immediately. Record your findings. TESTING THE UNKNOWN Carefully repeat each of the above steps by using a small amount (a few grams) of the unknown. Record all the results on your Powder Analysis Chart. o For each test, note whether a reaction occurs and, if so, describe what happens in detail, o including changes over time while running each test. For the HEAT TEST, be as specific as possible in describing the odor (remember to waft the smoke) and what it smells like. Identify the unknown based on the results you have obtained and complete the Laboratory Affidavit. List names of all lab group members; SIGN your own name. Note: You may have a different unknown than other lab groups so conduct your own testing and draw your own conclusions. Your unknown may contain one or two powders, so be careful in conducting tests and making your observations.

4 Rail Car and Powder 1. Powdered sugar Drawing of Powder Powder Analysis Chart Vinegar Test Iodine Test Heat Test 2. Salt 3. Baking Soda 4. Baking Powder 5. White Flour 6. Corn Starch 7. Plaster of Paris

5 Powder Drawing of Powder Vinegar Test Iodine Test Heat Test Unknown Environmental Powder Sample Sample # Powder Identification(s): Laboratory Affidavit Lab Group Member Signature of Researcher: Rail Car Number Contents Potentially Contaminated? Recommend Destruction? Recommend Safe to Use? 1 Sugar (powdered) Yes No Yes No Yes No 2 Salt Yes No Yes No Yes No 3 Baking Soda Yes No Yes No Yes No 4 Baking Powder Yes No Yes No Yes No 5 White Flour Yes No Yes No Yes No 6 Corn Starch Yes No Yes No Yes No 7 Plaster of Paris Yes No Yes No Yes No

6 Discussion and Analysis 1. List and explain four ways this exercise was similar or different from the scientific method. 2. Discuss at least two possible important implications/consequences of your having incorrectly identified the contaminated rail car. 3. Prepare a formal memorandum (NOT a formal lab report) for this exercise to be submitted to the Director of FEMA. Be sure to include the following in the appropriate sections of your memo. Identify and explain at least three variables that may have affected the reliability of your testing procedure. List and discuss possible confounding factors that may make your results incorrect.