Activity 3.2 - Ore Grades, Waste, and Remediation
Upon completion of this segment, students should be able to:
- Use spatial and quantitative skills to interpret geological information.
- Calculate the amount of metals obtained and the amounts of waste created through mining.
- Evaluate the impacts of various factors on an ore's cut-off grade.
- Compare the pros and cons of continuing mining in an area and weigh different remediation approaches.
Context for Use
Description and Teaching Materials
This activity is intended as a small-group (2–4 students) activity followed by whole-class review/discussion.
This activity has three different parts called "sections." Students will need most of an entire class time (40–45 minutes) to complete the entire handout (all three sections) and discuss. To complete the activity in about 25 minutes instead, each student group should complete only one of the three sections (in about 15 minutes), each group a different section. In this situation, the instructor would divide this handout into three separate handouts, each handout going to a different section. At the end of class, the instructor should ask groups to briefly summarize the questions they worked on (and their answers) and lead discussion to ensure the concepts are shared between groups.
Ore Grades, Waste, and Remediation Student Handout in Word (Microsoft Word 2007 (.docx) 8.8MB Oct5 14) and in PDF. (Acrobat (PDF) 3.5MB Oct5 14)
Teaching Notes and Tips
- It might be helpful to review the definitions of "ore grade" and "cut-off grade" at the start of the activity.
- This activity includes the use of some basic math skills. Instructors might want to work through sample calculations if they think students will struggle with the proportions and unit conversions used in this activity.
- Ideally students will complete this activity in groups, although the activity can be done individually.
- This activity can be used after the Muffin Mining activity OR it can be used instead of the Muffin Mining activity (but still after a discussion of mining methods based on the pre-class reading/PowerPoint [found here: Unit 3 Pre-Class Reading] and the optional pre-class homework on the Abandoned Mine Lands & SuperFund/National Priorities List) as determined by the amount of class time and the interests of the instructor.
- If class time is limited, then students should be broken up into small groups. Each group will do only one section of the activity (it has three sections), and then the instructor should follow up with a review/discussion so that each group is exposed to each section. Ideally, students can present their results and explain their section to the rest of the class. There can be more than one group working on each section, so long as all three sections are completed.
- If the instructor has more time, students should still be broken up into small groups, but each group can complete the entire activity (all three sections).
- Either way, this should be followed up by a class discussion.
- In addition to each group reviewing their activities, the instructor can, once again, ask students their impressions of their results, and the types of social and environmental decisions that need to be made in the context of resource recovery.
- Each group may need basic calculators (most cell phones are sufficient). Student groups working on Section 1 will need two different colored markers per group.
- If printing out for the class in color is an issue, then the activity can be printed out in grayscale. It might be helpful to project (on a screen) the satellite map in color (provided in the PowerPoint version above).
- The data (in Excel) from the Section II graphs are provided below (References and Resources Section).
Assessments and Learning Outcomes
The learning outcomes are addressed by the activity questions as listed below:
- Use spatial and quantitative skills to interpret geological information: Calculations, map reading, and area estimates in Section 1; Graph reading and calculations in Section 2; Determination of ore grade trends in Section 3; Group discussion.
- Calculate the amount of metals obtained and the amount of waste created through mining: Questions in Sections 1 and 2; Group discussion.
- Evaluate the impacts of various factors on an ore's cut-off grade: Questions in Sections 2 and 3; Group discussion.
- Compare the pros and cons of continuing mining in an area and weigh different remediation approaches: Questions in Sections 2 and 3; Group discussion.
An instructor can decide to (a) not collect or grade this assignment at all but use it to inform class discussion and information, (b) grade its completion (or level of completion) briefly, or (c) grade the individual answers for each of the questions.
An answer key is provided (see Description and Teaching Materials section above). For the thought questions, the students may provide answers additional to the ones in the answer key.Some possible post-Unit 3 assessment questions appear on the Unit 3 page.
References and Resources
- If still available, this video/article from the Bozeman Daily Chronicle might be helpful: Video on Golden Sunlight Mine.
- Excel spreadsheets with data used to create the plots in Section 2 from the Mudd, G. M. 2009. report: Graphs A and B Production (Excel 2007 (.xlsx) 62kB Oct4 14) and Graph C Ore Grades. (Excel 2007 (.xlsx) 55kB Oct4 14)
- Data from: Mudd, G. M. 2009. "The Sustainability of Mining in Australia: Key Production Trends and Their Environmental Implications for the Future." Research Report No RR5, Department of Civil Engineering, Monash University and Mineral Policy Institute, Revised April 2009. Downloaded from http://users.monash.edu.au/~gmudd/files/SustMining-Aust-Report-2009-Master.pdf.