We conducted field observations in order to help us gather information about the waste problem in Cantera. Our liaisons, Alfredo Zapata and Luis Cintrón, guided us around the area to observe instances of open dumping, the current ineffective waste collection system, and potential sites for the waste collection facility. Using a satellite image of Cantera from Google Maps, these important locations were recorded with photographs and qualitative comments. These comments included the compositions of dump sites and overflowing trash bins, locations of potential sites for a waste collection facility, and important locations around the community that are pertinent to
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our project, such as the office of the Consejo Vecinal which is made up of Cantera’s local leaders and explained further in section 3.2. Using this information, we created a detailed log
corresponding to these locations, and a map identifying these points. We took a satellite image of the community from Google Earth and then we used the GoogleDraw function to label these points. We were able to identify these locations on an image because we took the GPS
coordinates of each site. In this map, the blue circles indicated problematic waste areas, the red squares showed the location of the potential sites for the waste collection facility, and the yellow triangles marked the important agencies that are pertinent to the proposed facility. This helped inform the siting process we undertook later because it provided a clearer understanding of the physical layout of the community.
Trash Audit
In order for us to learn about Cantera’s waste challenges, it was important to determine the amount and composition of the waste that the community produces. To do so, we performed a “trash audit”, an experiment in which community members were asked to dispose of their waste in provided bags so the contents can later be quantified. Throughout the United States, trash audit campaigns have been a popular way to assess weight and composition of waste. A successful example of this practice is seen in Earth 911’s waste audit of the Phoenix waste stream (True Life, 2010). Earth 911 is an organization that for the past 20 years has promoted environmentally friendly practices such as recycling and purchasing sustainable products. Their study found valuable information such as households throwing away a large number of
recyclables.
To execute this, three trash bags were distributed to participating households, two 13 gallon white trash bags and one 30 gallon black trash bag. Participants were instructed to dispose of recyclables in the white trash bags, and the rest of their waste in the black bag. Recyclable items for this experiment include plastic, paper, glass, aluminum, cardboard, and newspaper. By separating the types of wastes we were able to quantify how much of the total waste was
composed of recyclables. This information allowed us to explore the need for collaboration with Reciclaje del Norte (refer to section 4.4). This also allowed us to estimate the total amount of domestic waste that is on average produced by the citizens of Cantera. Items that participants were instructed not to dispose of include hazardous waste, sharp objects, liquids, batteries, and
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The participating households were selected via recommendations from the CDIPC.
These participants were provided a set of instructions (refer to Appendix C), a survey (refer to Appendix D), and the three trash bags. The survey was used to understand the waste habits of the individuals, as well as to gather information regarding waste composition and quantity from each of the sectors. To minimize the possibility that participants would alter their normal waste
disposal practices, all participants were informed prior to participation that the content of their trash bags would remain private and that they should continue their regular disposal habits. In order to keep track of each participant, household, and survey, each set of bags was assigned a number between one and 32. We attempted to distribute our 32 samples evenly across Cantera, which comprises 16 sectors, as seen in figure 8 below.
Figure 8: Map of the 16 sectors of Cantera, courtesy of the CDIPC
In order to give a sufficient time period to accumulate waste, the participants were asked to begin accumulating waste in the bags on Saturday, November 8th at noon, and conclude on Monday, November 10th at noon. Some of the filled bags were dropped off at the CDIPC headquarters by the participants, while we picked up the rest at the participants’ houses. We did not have access to anything more than a basic analog scale which was too small to weigh the
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bags directly. Therefore, the weight of each bag was measured through one person standing on a scale and recording his or her weight and then repeating this while holding the bag as seen in figure 9. The difference between the two measurements provided the weight of the bag. The bags were not opened for a more detailed record of the waste composition.
Figure 9: Example of measuring the bags in the trash bag audit
Through this campaign, we collected data regarding waste composition and generation rates per household. Once the measurements of weight had been recorded and the corresponding surveys were collected, all the information was compiled in a Microsoft Excel spreadsheet. This spreadsheet included each participant’s unique identifier, their demographic information, and waste measurements. The measurements of waste weight were used to project each person’s annual waste production for both recyclables and non-recyclables. We assumed that this two-day period was representative of normal waste disposal. We used this information to extrapolate to the entire community, generating an estimate of the community’s yearly waste production. We used the estimation of 10,000 residents in the community of Cantera, based on the demographic information provided by the CDIPC (refer to Appendix A). Using Excel’s Pivot Table and Chart feature, we created multiple views of the data to assess the percentage of recyclables and other waste being disposed of. This feature was also used to investigate spatial variability in waste production between sectors. We did this by comparing the unit waste generation per person by
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sector. A proper facility design that fits the community’s needs was determined by quantifying the current weight and composition of waste in Cantera (objective 3). Finally, we used a two sample t-test to see if there was a significant difference between combined waste and recyclable generation in the barriadas and the subsidized housing. If there was a significant difference between waste generations in these types of household, accommodations would have to be made such as siting the facility in an area with higher waste generation, or education on how to reduce waste generation.
3.2 Identifying the Key Stakeholders’ Opinions of the Potential Establishment