Embedded Files
Authored by: James Rice, chemistry and physics teacher at Northridge Academy High School
Location:
Sunshine Canyon Rd, Sylmar,
CA 91342
Description:
The Sunshine Canyon landfill is located immediately to the west of the junction between the 5 and 14 freeways just north of Sylmar and just south of Santa Clarita, allowing it to be remarkably convenient in terms of proximity to the source of waste but far enough removed to prevent unwanted odor and immediate risk of leachate contamination. As the name implies, it is situated in a canyon, making it an ideal spot for collecting large volumes of solid waste.
As of 2015, Sunshine Canyon annually took in about 45% of all solid waste deposited in Los Angeles County landfills, making it currently the largest single recipient of solid waste in the county.
Audience:
Great for environmental science teachers to talk about how toxins can enter, or be prevented from entering, soil and the subterranean waters. Also great for discussing carbon cycling due to methane and CO2 production. This could also pair well with a sewage treatment field trip.
Potentially useful for biology teachers to talk about a large-scale example of anaerobic respiration due to the bacteria that break down biological materials while buried in an anoxic environment.
Useful for earth science teachers because it provides a microcosm of the way water processes through soils, and stressing how the design of a landfill is meant to prevent the entry of toxins into groundwater.
This would also be an excellent tie-in to Brie-anna Molina's Design a Landfill engineering project. The trip could either be used to present engaging phenomena or as the culmination of the students' design process in which, prepared by their previous work, students would be able to gain deeper insight into
Science Concepts Addressed: The following science concepts can be addressed by a field trip to the Sunshine Canyon Landfill.
Aqueous solutions: Water is arguably the most important substance on earth for life, even ahead of oxygen, particularly because it dissolves such a wide variety of other compounds, allowing them to collide more often because they are held together in the condensed, but mobile, liquid phase. So, water, in the form of rain, is also able to dissolve countless materials that find themselves in landfills, creating leachate. Because of gravity, and if there is any leakage in the bottom of the landfill, leachate can enter groundwater, which is covered in the study of hydrology. This leads us to...
Watershed Hydrology: In general, landfills produce considerable amounts of liquid leachate. Being able to predict where leachate may go depends on understanding hydrology, the study of how water flows both above and below the surface of the earth.
Groundwater Discharge: Water that accumulates underground is able to run off if its substratum has any vertical exposure. The pipes used for allowing leachate to run off act as an artificial version of this phenomenon, demonstrating it in a very concrete way.
Anaerobic Respiration: Methane and carbon dioxide are produced by bacteria inside the waste through the process of anaerobic respiration, rather than our more familiar aerobic respiration, because the compaction of waste under soil cuts off access to oxygen. The teacher can point out that organisms can perform metabolic processes under a wide variety of environmental conditions, and also illustrate how, generally, fungi and bacteria can be much hardier than everyday experience would point to. This might also be a good time to discuss extremophiles (thermophiles, halophiles, etc.)
Engineering Design: Considerable engineering goes into ensuring that the waste and all the materials contained in and produced by it stay isolated in the landfill without infiltrating the geosphere, hydrosphere, or atmosphere. Particularly in connection with the design challenge already mentioned above, the landfill can be used to showcase the engineering design process, and help students to see how the engineering elements that they have developed in the classroom are actually relevant to real-world work.
Photo and Video Gallery:
Virtual Tour of Rhode Island's Central Landfill
A cutaway illustration of the multiple layers of a modern landfill
A new landfill having its liner installed
Installation technician joining pieces of liner together to insure they are water tight and prevent leachate from infiltrating the soil.
Active landfill cell at Shepard Waste Management facility
Rain runoff running down the cap of a finished landfill
Pipes collecting methane gas produced by anaerobic bacteria inside the buried waste
A close-up of leachate pouring from a collection pipe
A leachate collection pond
A schematic for one of many proposed methods for decreasing color and chemical oxygen demand (COD) in leachate through electrocoagulation (highlights and abstract here)
For additional information:
Page updated
Google Sites
Report abuse