Whitaker Ponds Natural Area Remediation Project: Response of Macroinvertebrate Communities One Year Post-Remediation
Start Date
4-4-2023 3:30 PM
End Date
4-4-2023 3:39 PM
Abstract
East and West Whitaker Ponds are located along the Columbia Slough, surrounded by industrialization. Metro Metals, a metal recycling plant directly behind East Whitaker Pond, historically drained untreated water into the pond until 2008 when a stormwater treatment was put in place. After the Department of Environmental Quality (DEQ), discovered contaminants, including heavy metals, pesticides, PCBs, semi-volatile organic compounds, and PAHs in East Whitaker Pond, Metro Metals and DEQ collaborated on remediation of the pond in 2021 by placing a protective six-inch cap on the contaminated sand. After remediation, the pond was refilled naturally by rainwater and groundwater to allow aquatic plants and animals to repopulate the area. We collected three years of pre-remediation (2018-2020) and one year of post-remediation (2022) aquatic invertebrate community samples. Samples were taken once per month from April to October from six locations in Whitaker Ponds, four locations in the East Whitaker Pond and two in West Whitaker Pond. Aquatic invertebrates were identified to family, and richness and abundance were determined. A non-metric multidimensional scaling (NMDS) and linear regression analysis was performed in R to examine community shifts pre- and post-remediation. With only one year of post-remediation data, the NMDS did not show a community shift. However, linear regressions over time did show a modest increase in both richness and abundance. With our initial year of post-remediation data, Whitaker Ponds tentatively appears to be an example of an urban aquatic community's resilience to contamination and positive response to remediation efforts.
Subjects
Habitat restoration, Land/watershed management, Water quality
Persistent Identifier
https://archives.pdx.edu/ds/psu/40489
Whitaker Ponds Natural Area Remediation Project: Response of Macroinvertebrate Communities One Year Post-Remediation
East and West Whitaker Ponds are located along the Columbia Slough, surrounded by industrialization. Metro Metals, a metal recycling plant directly behind East Whitaker Pond, historically drained untreated water into the pond until 2008 when a stormwater treatment was put in place. After the Department of Environmental Quality (DEQ), discovered contaminants, including heavy metals, pesticides, PCBs, semi-volatile organic compounds, and PAHs in East Whitaker Pond, Metro Metals and DEQ collaborated on remediation of the pond in 2021 by placing a protective six-inch cap on the contaminated sand. After remediation, the pond was refilled naturally by rainwater and groundwater to allow aquatic plants and animals to repopulate the area. We collected three years of pre-remediation (2018-2020) and one year of post-remediation (2022) aquatic invertebrate community samples. Samples were taken once per month from April to October from six locations in Whitaker Ponds, four locations in the East Whitaker Pond and two in West Whitaker Pond. Aquatic invertebrates were identified to family, and richness and abundance were determined. A non-metric multidimensional scaling (NMDS) and linear regression analysis was performed in R to examine community shifts pre- and post-remediation. With only one year of post-remediation data, the NMDS did not show a community shift. However, linear regressions over time did show a modest increase in both richness and abundance. With our initial year of post-remediation data, Whitaker Ponds tentatively appears to be an example of an urban aquatic community's resilience to contamination and positive response to remediation efforts.
