Building community knowledge,resilience and resistance through research

Skyrocketing housing costs in the U.S. have fueled research on gentrification, displacement, and neighborhood change, addressing how development processes impact low-income and working-class neighborhoods. Scholars have pointed to the importance of community-based knowledge in understanding the impact of gentrification at the neighborhood level (Chapple, Loukaitou-Sideris, Gonzalez, et al. 2017a; Chapple, Loukaitou-Sideris, Waddell, et al., 2017b) as well as how spatial knowledge informs organizing and activism of community-based organizations (Maharawal & McElroy, Annals of the American Association of Geographers, 108(2):380–389, 2018; Fields, Journal of Urban Affairs, 37(2):144–165, 2015; Elwood 2006a, The Professional Geographer, 58(2):197–208, 2006b). Despite the increasing research, less has centered on the knowledge of community organizers and residents in gentrifying neighborhoods and how community-driven mapping contributes to understanding of neighborhood level change from gentrification. This article presents a case study of community-driven research, analysis, and organizing of the Northeast Los Angeles Alliance (NELAA) a community-based member collective organization in Northeast Los Angeles with support of its academic partner Occidental College. The case study illustrates how community-driven research tied to organizing in the form of “countermapping” challenges the dominant practice and narrative of top-down property-centered development (Mahawaral and McElroy 2018). Further, the case study illustrates new ways to incorporate community knowledge into understanding of gentrification, displacement, and neighborhood change by: (1) introducing community-based collectives as particular types of community-based organizations utilizing community mapping and GIS; and, (2) illustrating detailed changes at the block and neighborhood levels by recognizing community-driven research and mapping as a source of in-depth and spatially specific historical knowledge and community vision.

     

Characterization and treatability of a contaminated soil from an oil exploration zone

A crude contaminated soil, arising from an oil production zone in Tabasco, Mexico was studied. A sample of about 40 kg was dried and screened through meshes 10–100. Total petroleum hydrocarbons and 6 metals (Cd, Cu, Cr, Ni, V and Zn) were determined to the different portions. For soil which passed mesh 10, six non-ionic, three anionic and one zwitterionic surfactant solutions (0.5%) were employed to wash the soil. Additional tests using surfactant salt mixtures and surfactants mixtures were carried out. Once the best soil washing conditions were identified, these experimental conditions were applied for washing the rest of the soil portions obtained (meshes 4, 6, 20, 40, 60, 80, 100). Total petroleum hydrocarbons values were in the range of 51, 550 to 192, 130 mg/kg. Cd was not found in any of the soils portions, and the rest of the metals were found at different concentrations, for every soil mesh. Treatability tests applied to the soils indicated that it is possible to get removals between 9.1 to 20.5%. For the case of a sodium dodecyl sulphate 1% solution, total petroleum hydrocarbons removal was as high as 35.4%. Combinations of sodium docecyl sulphate and salts, gave removal rates up to 49.5%. Total petroleum hydrocarbons concentrations for the whole soil were about 150,600 mg/kg. The higher the particle size, the lower the washing removal rate. The combined effect of particle size and total petroleum hydrocarbons concentration, determines the total petroleum hydrocarbons removal efficiencies. These facts are very important for designing an appropriate soil washing remediation process.