ABSTRACT

A solid waste landfill siting exercise has been developedfor an introductory environmental geology course.Students are asked to site a county landfill using theactual state guidelines developed and enforced by theWisconsin Department of Natural Resources. Thestudents work in small groups and synthesizeinformation from a variety of resources, including mapsof geology, hydrology, land use, and topography. Afterchoosing a site, students explain the benefits anddrawbacks of the chosen location in oral and writtenformats. The exercise asks students to draw on a varietyof topics and skills explored earlier in the term and toapply them to a real-world environmental problem. Ithas been successfully implemented as a capstone projectat a liberal arts college and a large public institution.

INTRODUCTION

Introductory environmental geology courses have thedaunting goal of providing students with the frameworkfor asking appropriate questions about the myriad ofenvironmental issues they will encounter in everydaylife. The applied nature of these issues makesproblem-based learning especially applicable to suchcourses (Lev, 2004). Cooperative learning, in whichstudents work in groups to achieve a common goal, canalso prove effective because environmentalproblem-solving often requires disciplinary diversity(NRC, 1997).

Wisconsin's landfill siting process provides atemplate for a capstone project that challenges groups ofstudents to analyze a diverse data set and propose asolution to a real-world geo-environmental problem.Successful capstone courses implemented forenvironmental geoscience programs stress small-groupidentification, analysis, and solution of problems that ageologist might encounter as a consultant or in anindustrial or regulatory role (Harbor, 2000). Capstoneprojects for introductory environmental geology coursesshould similarly model realistic situations by askingstudents to apply geologic knowledge drawn from workearlier in the term, interpret new site-specificinformation, and present their conclusions inprofessional written and oral formats.

A capstone project based on waste managementissues asks students to face an environmental problemthat we all contribute to, but to do so from a geologicperspective. The topic is well suited for a capstoneexercise because a landfill's ability to isolate solid andliquid waste is largely determined by its geologic andhydrologic setting, and solid waste managementtypically appears as a later chapter in widely used

environmental geology textbooks (e.g., Montgomery,2003; Pipkin et al., 2005). The subject also raisesinteresting and important societal questions regarding,for example, environmental justice, waste reductionstrategies, and reclamation of land after filling iscomplete.

Wisconsin's landfill siting process balances the needfor environmentally sound disposal of solid waste withthe concerns of local citizens. All new landfills in the statemust obtain both local and state approval prior toconstruction. The first step in the process is the initial siteinspection (Figure 1), the purpose of which is to obtain apreliminary evaluation from the Wisconsin Departmentof Natural Resources (WDNR) regarding the potential ofa proposed property to meet location and environmentalperformance standards as specified in the WisconsinAdministrative Code (s. NR 504.04) (Table 1). A requestfor an initial site inspection must be accompanied by acover letter that identifies the applicant, the type of solidwaste storage facility proposed, its proposed location byquarter-quarter section, and the present land use. Inaddition, applicants are encouraged to submit theLandfill Initial Site Inspection Request CompletenessChecklist (available at http://dnr.wi.gov/org/aw/wm/solid/landfill/ldfisicklist.pdf) (Huebner, 1996), aform that outlines general submittal requirements andlandfill request minimum requirements for an initial siteinspection. The landfill siting exercise presented here isbased on the preliminary environmental assessmentrequired to evaluate whether a site meets the locationand environmental performance standards as specifiedin the Wisconsin Administrative Code (Wis. Adm.Code).

GOALS OF THE EXERCISE

The overall objective of this exercise is to site a 150-acresolid waste landfill for a county in Wisconsin. Students insmall groups identify a convenient and environmentallyfriendly location for the landfill. Additional goals are tosynthesize information for an unfamiliar setting from avariety of maps and to explain the benefits anddrawbacks of the chosen location in oral and writtenformats.

The landfill siting exercise is intended to promotestructural and multidimensional levels of learning, asdefined by the Biological Sciences Curriculum Study(1993) and the Geoscience Academic Excellence Model(Brunkhorst, 2002). A structural level of learning is when"students construct appropriate explanations based onexperience and discuss and explain concepts in their ownterms," and a multidimensional level is when "studentsapply the knowledge gained and skills developed tosolve real problems that may require the integration of

458 Journal of Geoscience Education, v. 54, n. 4, September, 2006, p. 458-463

A Solid Waste Landfill Siting Exercise for an IntroductoryEnvironmental Geology Course

Susan K. Swanson Beloit College, Department of Geology, 700 College Street, Beloit, WI 53511,swansons@beloit.edu

Jean M. Bahr University of Wisconsin, Department of Geology and Geophysics, 1215 W.Dayton Street, Madison, WI 53706, jmbahr@geology.wisc.edu

Jeffery D. Wilcox University of Wisconsin, Department of Geology and Geophysics, 1215 W.Dayton Street, Madison, WI 53706, jwilcox@geology.wisc.edu

information from other disciplines within and outside ofscience" (Brunkhorst, 2002, p. 76).

BACKGROUND AND LABORATORYMATERIALS

Throughout an environmental geology course, studentsdevelop the skills to interpret maps of topography,bedrock geology, glacial geology, soils, and the watertable. However, individual laboratory exercises oftentreat the subjects separately, highlighting interesting andrelevant examples for each. To site a landfill, studentsmust interpret maps simultaneously, which drawsattention to relationships among the different types ofdata. For example, in Wisconsin wetlands are commonly

found on former glacial lakebeds, and sandy soilsdevelop on outwash plains. Although such relationshipsare emphasized earlier in the term, this exercise createsan additional opportunity for students to reason throughsuch relationships, or recognize new ones, in anunfamiliar setting.

Many land fills in Wis con sin are man aged or op er-ated at the county level. The num ber and en vi ron men taldi ver sity of coun ties in Wis con sin al low the es tab lish-ment of groups of stu dents, each of which is re spon si blefor sit ing a land fill in a sin gle county. U.S. Geo log i calSur vey top o graphic maps for coun ties in Wis con sin(1:100,000 scale) are avail able at the Wis con sin Geo log i-cal and Nat u ral His tory Sur vey (WGNHS, http://www.uwex.edu/wgnhs/pubs.htm). The WGNHS also pub-lishes maps de tail ing the state's Pleis to cene ge ol ogy,

Swanson et al. - Solid Waste Landfill Siting Exercise 459

Figure 1. Wisconsin’s Landfill Siting Process (modified from Huebner, 1996). An asterisk (*) indicates that areport is required.

Location Standards Performance Standards

According to s. NR 504.04 (3), the proposed facility will be(a) At least 1,000 feet from navigable lakes, ponds, or

flowage.(b) At least 300 feet from navigable rivers and streams.(c) Outside of all floodplains.(d) At least 1,000 feet from any state and federal highway,

right-of-ways, and public parks, or will be screened andnot visible.

(e) At least 10,000 feet from airport runways, 5,000 feetfrom piston airport runways, and not create asubstantial bird hazard.

(f) At least 1,200 feet from public water supply wells.(g) At least 200 feet from a fault that has had displacement

in Holocene time.(h) Outside seismic impact zones.(i) Outside unstable areas.

According to s. NR 504.04 (4), the proposed facility will nothave

(a) An impact on any wetlands.(b) A significant adverse impact on critical habitat areas.(c) A detrimental effect on any surface water.(d) A detrimental effect on groundwater quality or will

cause an impact that will exacerbate an attainment orexceedance of any ch. NR 140 preventative action limitor enforcement standard.

(e) A concentration of explosive gases which exceed 25% of the lower explosive limit for such gases in structures,soils or air beyond the facility property boundary.

(f) A concentration of any hazardous air contaminantexceeding the limitation for those substances containedin s. NR 445.03.

Tabel 1. Location and environmental performance standards as specified in the Wisconsin AdministrativeCode (s. NR. 504.04).

bed rock ge ol ogy, ground wa ter, and soils at the countylevel (Ta ble 2). Most of the maps are pub lished at scalesof 1:100,000 or 1:250,000. We have suc cess fully usedseven coun ties for this ex er cise, in clud ing Ad ams,Barron, Dane, Mar a thon, Polk, Por tage, and Wood. Forcoun ties that do not yet have a com plete suite of re-sources, state level maps are avail able. How ever, we rec -om mend the state-level maps in Ta ble 3 to com ple mentthe county-level maps even when the larger scale mapsare avail able for a par tic u lar re gion. Other ba sic lab ma te-ri als that are use ful for the ex er cise in clude rul ers, cal cu-la tors, and Pub lic Land Sur vey Sys tem (town ship, range,and sec tion) tem plates.

DESCRIPTION OF LANDFILL SITINGACTIVITIES

After introducing general information on wastemanagement, such as disposal methods, hazardsassociated with municipal waste disposal, and landfilldesign, we discuss as a class each step in the landfilllicensing process (Figure 1). In doing so, studentsdevelop an appreciation for the diverse expertise andobjectives of the stakeholders involved (e.g., applicants,consultants, regulators, local citizens) and theimportance of documentation and writing in the process.This discussion also provides a framework for the rolethe students are playing in their initial site assessment.Students are then divided into groups of two to four.They are told that the solid waste facility will occupy 150acres. The landfill will be constructed with a liner andleachate collection system, which requires excavation to

approximately ten feet below the existing groundsurface.

We encourage each group to consider the purposeand significance of the location and performancestandards in the WDNR landfill siting criteria (Table 1) asthey formulate a strategy to accomplish their task. Mostof the location standards are relatively straightforwardrequirements that are intended to provide buffers, orsetback distances, around sensitive features orresidential areas (s. NR 504.04 (3) (a) - (f)) (Huebner,1996). Of these criteria, a few require information that isnot readily available for every county. For example,landfills cannot be sited within 1,200 feet of public watersupply wells. If water table maps do not show welllocations, we apply the buffer to municipal boundariesbecause most municipal wells are drilled within citylimits. Some of the location standards refer to thepotential for geologic hazards, like seismic activity ormass wasting processes (s. NR 504.04 (3) (g) - (i)), andtherefore demand more in-depth evaluation of thebedrock and Pleistocene geology maps.

The performance standards insure against adverseimpacts on critical resources and habitats (Table 1).Several of the standards are considerably vague, whichusually generates discussion within groups. The firstfour standards require an evaluation of the hydrologicresources in the county. At this stage in the licensingprocess, the WDNR does not require full evaluation of s.NR 504.04 (4) (d), which refers to Wisconsin's drinkingwater regulations (ch. NR 140); however, we suggest toour classes that the base of the landfill should be at leastfive feet from the seasonal water table high to add amodest level of protection to groundwater resources.

460 Journal of Geoscience Education, v. 54, n. 4, September, 2006, p. 458-463

Pleistocene Geology1 Bedrock Geology1 Water TableSoilAttenuationPotential

1:100,000 1:250,000 1:100,000 1:250,000 1:100,000 1:100,000

Adams Ashland Juneau Ashland Pierce Adams Ozaukee Adams3

Barron Bayfield LaCrosse4 Barron Polk Barron Pepin Barron

Brown Douglas Marathon Bayfield Price Brown Pierce Chippewa

Dane2 Iron Portage Buffalo Rusk Buffalo Polk Dunn

Florence4 Sauk4 Burnett Sawyer Burnett Portage3 Eau Claire

Forest4 Wood Chippewa St. Croix Chippewa Price Langlade

Juneau Clark Taylor Clark Sauk4 Pepin

Langlade4 Douglas Trempleleau Columbia St. Croix Pierce

Lincoln4 Dunn Vilas Dane2 Trempeleau Polk

Marathon Eau Claire Washburn Dodge Vilas Portage

Ozaukee Florence Dunn Walworth St. Croix

Polk Forest Eau Claire Washington Trempeleau

Portage Iron Jackson3 Waukesha Wood

Sauk4 Jackson Jefferson Waupaca3

Taylor Langlade Juneau3 Waushara3

Vilas4 Lincoln Landlade Wood3

Washington Marinette Marathon3

Waukesha4 Oneida Marquette3

Wood Pepin Monroe3

Table 2. County level maps published by the WGNHS. Notes: 1 State level bedrock geology and glacial geologymaps are also published by the WGNHS (see Table 3). 2 Additional Dane County maps are available in WGNHSOpen-File Report 1999-04 (Bradbury et al., 1999). 3 Water table elevation maps for these counties areincluded in WGNHS Miscellaneous Paper 81-1 (Lippelt and Hennings, 1981). 4 Also published in digital format.

This guideline is taken from requirements for othernon-landfill solid waste facilities in the state (ch. NR 502,Wis. Adm. Code). The last two performance criteria (s.NR 504.04 (4) (e) and (f)) refer to explosive limits forgases and control of hazardous air pollutants. Studentsdo not evaluate these criteria because the WDNR doesnot require reporting of potential conflicts with thesestandards at this stage in the licensing process andevaluation would require information that is beyond thescope of the course.

The process of introducing the exercise, discussingthe landfill siting process, and assigning student groupscan be completed in one 50-minute class period. Detailedsuggested schedules of activities for the entire exerciseare discussed below.

EVALUATION

Students are evaluated as a group and/or individually.One week after the students begin the exercise, eachgroup presents their results to the class in a 10- to15-minute presentation (including time for questions).Groups are evaluated by the instructor for organizationand clarity, their description of the geologic setting, andthe benefits and drawbacks of the proposed site. In someyears, the other students in the class also evaluated eachgroup. Peer evaluation has the advantage of engaging allstudents and generating more questions during and aftereach presentation.

Students also write a cover letter to a solid wastespecialist at the WDNR (i.e., the instructor) requesting an initial site inspection of the proposed site. The letter canbe written individually or as a group, and it is due on thelast day of the group presentations. The WDNR LandfillInitial Site Inspection Request Completeness Checklist(available at http://dnr.wi.gov/org/aw/wm/solid/landfill/ldfisicklist.pdf) can serve as a guide for contentand it can be included as an attachment to the letter. TheGeneral Submittal Requirements outlined on thechecklist refer to any report submitted in the licensingprocess (e.g., initial site report, feasibility report, plan ofoperation, as-built documentation report) (s. NR509.04,Wis. Adm. Code). Because the request for an initial siteinspection requires only a cover letter and not a report(Figure 1), students should read through therequirements, but they do not need to compile a report.

The Landfill Request Minimum Requirementsoutlined on the checklist specify information that anapplicant must submit at this stage in the licensingprocess and provide a template for the students' coverletters. The first requirement is the cover letter itself;students should include all of the information listedunder this requirement. The second and thirdrequirements are letters from the Bureau of EndangeredResources and the Wisconsin State Historical Society.

The purpose of these letters is to demonstrate that anyhistorical, scientific, or archaeological areas within thevicinity of the proposed landfill and any critical habitatareas and state or local natural areas within one mile ofthe proposed landfill have been identified (s. 509.04 (4),Wis. Adm. Code). Although these are importantrequirements in the landfill siting process, we do not askstudents to submit corresponding letters. The fourth andfifth requirements describe the environmentalconditions in the vicinity of the proposed site andcompliance with the location and performance standardsdiscussed earlier (Table 1). The WDNR asks for a map todescribe the environmental conditions. In a moreadvanced environmental studies course, students couldbe asked to draft such a map. However, we instruct ourstudents to describe this information in an organizedmanner in their cover letters, in addition to discussingcompliance or potential conflicts with the location andperformance standards.

SUGGESTED SCHEDULES OF ACTIVITIES

The exercise has been completed six times in classes ofapproximately 20 students (Beloit College) and threetimes in classes of up to 120 students (University ofWisconsin-Madison). The Beloit College course meets forfour 50-minute lecture/discussion sessions with onethree-hour lab session per week. One three-hour labsession is generally sufficient for the instructor tointroduce the exercise, the class to discuss the steps in thelandfill licensing process, and the student groups toidentify several potentially viable sites in their assignedcounty. One additional 50-minute class period is oftenreserved for final decisions regarding proposed sites,initial discussions regarding class presentations, and anyremaining questions. Up to two 50-minute class periodsare reserved for the presentations. Students are expectedto write individual cover letters outside of class andsubmit them along with any supplementary materials.The cover letters are due approximately a week and ahalf after the students begin the exercise.

The University of Wisconsin-Madison (UW-Madison) course meets for two 50-minute lecturesessions and one 50-minute discussion session per week.Discussion sections typically have approximately 20students. One 50-minute discussion session is utilized forthe instructor to introduce the exercise, for the class todiscuss the steps in the landfill licensing process, and forthe groups of students to begin working on the sitingprocess. Students are expected to meet outside of class tocomplete the siting process. Class presentations arespread out over the following two weeks during thediscussion sections. Students are expected to write coverletters as a group, instead of individually, and submitthem along with any supplementary materials. Coverletters are due approximately three weeks after thestudents begin the exercise.

ASSESSMENT

Students who completed this assignment at BeloitCollege and the UW-Madison in Spring 2004 agreed toparticipate in a survey to help assess learning andevaluate the design of the exercise. The survey, approvedby each institution's respective Institutional ReviewBoard, asked which maps and steps in the landfill sitingprocess needed additional explanation. The number ofresponses corresponding to each map (Figure 2a) or step

Swanson et al. - Solid Waste Landfill Siting Exercise 461

Map Title Scale

Bedrock Geology Map ofWisconsin 1:1,000,000

Glacial Deposits ofWisconsin

1:500,000

Landscapes of Wisconsin 1:500,000

Wisconsin Land Cover 1:500,000

Table 3. Supplementary state level maps for the solidwaste landfill siting exercise.

(Figure 2b) is normalized to the size of the Beloit Collegeand UW-Madison classes to ease the comparison ofresults. Students in both classes indicated that theyunderstood most of the maps and that the landfill sitingprocedure is clear. Survey responses were supported byexplanations in the cover letters. Most students did asufficient job of explaining the benefits and drawbacks oftheir proposed landfill site.

In both classes some students wanted additionalexplanation of the soil attenuation potential map (Figure2a). Neither course devoted an entire chapter to soils in2004, but the Beloit College course covered topics relatedto soils at other points in the term, instructors in bothcourses provided additional explanation of the mapduring the introduction to the exercise, and a completediscussion of soil attenuation is provided on each map.However, comments on the surveys suggest that theconcept of soil attenuation potential remained confusing.Students also had trouble explaining the informationdisplayed on this type of map in their own words. Forexample, they referred to the map by a variety of titlesincluding, the "pollution attenuation map", the"attenuation of soil map", and the "soil solubility map."A smaller set of students in both classes indicated that thegeologic cross-sections on the Pleistocene maps neededfurther explanation (Figure 2a). Students in theUW-Madison course did not construct geologiccross-sections earlier in the semester. The Beloit Collegestudents, who did construct cross-sections, indicatedthrough survey responses and class discussion that a

source of confusion is the large vertical exaggerationused in these cross-sections.

To evaluate whether students could apply skills andknowledge gained throughout the term to the problem offinding an environmentally sound location for thelandfill, we also asked students which maps were mostand least useful in the process (Figure 2c and d). Figure2c shows that no single map was identified as mostuseful by a majority of students. In addition, manystudents indicated that all of the maps were useful (orthat none was least useful), which demonstrates theunderstanding that each map contains some, but not all,of the necessary information.

A number of students in both courses indicated thatthe soil attenuation potential map is the most usefulresource. In light of their responses to the first surveyquestion, some students may have relied heavily on amap that they did not fully understand. If the soilattenuation potential map is used, we recommendstressing that many environmental characteristics suchas slope, vegetation type, rock and unconsolidatedmaterial composition, in conjunction with soil,determine the overall potential of the environment toprotect groundwater. The specific WGNHS rankingsystem for evaluating the attenuation potential of soils isbased on texture, total depth, permeability, content oforganic matter, and pH (Good and Madison, 1987).However, soils typically comprise only the upper two tofour feet of unconsolidated materials at the earth'ssurface. Therefore, the soil attenuation potential mapshould be used in close association with the bedrock

462 Journal of Geoscience Education, v. 54, n. 4, September, 2006, p. 458-463

Figure 2. Student survey results from Beloit College (light gray) and the University of Wisconsin-Madison(dark gray). The number of responses are normalized to the respective class sizes.

geology map or the Pleistocene geology map. ThePleistocene geology map, in particular, appears to havebeen under-utilized by some groups; many studentsindicated that the Pleistocene map and cross-sectionswere the least useful resources (Figure 2c and d).

The last survey question asked students to providerecommendations for improvement to the design of theexercise. Overall, responses were very positive. Severalstudents commented that the exercise helped integratethe concepts they learned earlier in the semester. Othersappreciated the fact that the exercise emphasizeslinkages between human needs and environmentalconditions. Some counties do not have idealenvironmental conditions, but a landfill is necessaryunless residents are willing to pay for the high costs oftransporting solid waste.

Most of the recommendations involved providingadditional resources, although students realized that notall counties have identical resources available. Severalstudents suggested using floodplain maps, and becausesuch maps are available through the Federal EmergencyManagement Agency (FEMA), they could be easilyincluded. Many students also suggested residential anddetailed road maps. However, the county scaletopographic maps show federal, state, and county roads.Alternatively, students could be encouraged to find theirown supplementary materials if they think suchinformation would be useful.

CONCLUSIONS

The landfill siting exercise provides students with areal-world problem to which they can apply theirgeological expertise. Beloit College and UW-Madisonand are both located in Wisconsin, but we believe theexercise is applicable to any introductory environmentalgeology course. All of the resources necessary for theexercise can either be downloaded or ordered from theWGNHS. A complete set of maps for one county costs$15 - $25. Detailed assignments are also available fromthe first author.

The exercise is highly flexible and easily modified toaddress different environmental conditions by varyingcounties in Wisconsin or even using map sets fromdifferent states. The schedule of activities is also flexibleas demonstrated by the success of the exercise at bothBeloit College and UW-Madison, two institutions withvery different weekly course timetables.

Instructors can also incorporate role-playingactivities. For example, in the fall 2004 course taught atUW-Madison, three groups in each discussion sectionwere asked to site a landfill in different areas within thesame county. All three groups presented "sales pitches"for their chosen locations, and then were allowed todebate the relative benefits and drawbacks of each.Students who were not part of those three groups werethen asked to vote on the best location as if they weremembers of a local board. This variation of the exerciseresulted in students being more attentive during thepresentations and increased the amount of interactionbetween presenters and the audience. Students were also able to see that some decisions were not necessarily"right or wrong," but were based on prioritizingcompeting goals. For example, while one group saw treeremoval as a drawback at a proposed site, another groupintentionally chose a wooded site so the landfill wouldnot be visible from the highway. In many cases, theselected site - as voted by the other students -was

probably not the best of the proposed sites in a county;many students recognized the importance of aconvincing presentation style, both as engaged listenersand as presenters themselves.

ACKNOWLEDGMENTS

We thank the WDNR for their cooperation in explainingaspects of Wisconsin's solid waste management code andthe WGNHS for providing comprehensive lists of mapsavailable at the county and state level. We also thank thestudents in the spring 2004 environmental geologycourses at Beloit College (Environmental Geology andGeologic Hazards) and UW - Madison (EnvironmentalGeology) for evaluating this exercise.

REFERENCES

Biological Sciences Curriculum Study, 1993, DevelopingBiological Literacy, a guide to developing secondaryand post-secondary biology curricula, Dubuque, IA,Kendall/Hunt Publishing Company, 128 p.

Bradbury, K.R., Swanson, S.K., Krohelski, J.T., and Fritz,A.K., 1999, Hydrogeology of Dane County, WGNHSOpen File Report 1999-04, 66 p. + 2 color plates.

Brunkhorst, B.J., 2002, A working model for evaluatingacademic excellence in geoscience education,undergraduate, and K-12, Journal of GeoscienceEducation, v. 50, p. 72-77.

Good, L.W., and Madison, F.W., 1987, Soils of WoodCounty and their ability to attenuate contaminants,WGNHS Map 87-6.

Harbor, J.M., 2000, A capstone course in environmentalgeosciences, Journal of Geoscience Education, v. 48,p. 617-623.

Huebner, P.M., 1996, Wisconsin's Landfill Siting Process, Madison, WI, Bureau of Waste Management,Wisconsin Department of Natural Resources, 9 p.

Lev, S.M., 2004, A problem-based learning exercise forenvironmental geology, Journal of GeoscienceEducation, v. 52, p.128-132.

Lippelt, I.D., and Hennings, R.G., 1981, Irrigable LandsInventory - Phase I Groundwater and RelatedInformation, WGNHS Miscellaneous Paper 81-1.

Montgomery, C.W., 2003, Environmental Geology (6thedition), New York, McGraw-Hill, 554 p.

National Research Council (NRC), 1997, ScienceTeaching Reconsidered: a handbook, WashingtonD.C., National Academy Press, 88 p.

Pipkin, B.W., Trent, D.D., and Hazlett, R., 2005, Geologyand the Environment (4th edition), Belmont, CA,Brooks/Cole, 473 p.

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