U.S. Fish and Wildlife is partnering with Washington State University – Puyallup to evaluate improvements in the default bioretention soil mix (60 percent sand and 40 percent compost) capacity to reduce nutrient, bacteria, and metal pollutants when amended with fungal spores and plants. Toxicity to daphnids and zebrafish will be evaluated with the amended soils.
Study questions
The study’s sampling quality assurance project plan provides information on the sites and study design.
- Do fungal and/or plant amendments improve the effectiveness of the default bioretention soil mix to reduce metal, fecal coliforms, and nutrient pollution from highway runoff?
- Are the amended mixes still capable of preventing toxicity to aquatic organisms?
Study findings
Monitoring was underway through 2018.
Project tasks and deliverables
Scope of Work, Amendment 1
- Quality assurance project plan (QAPP) — Deliverable 1
- Build and condition bioretention cells, baseline testing of materials
- Baseline water quality, sediment chemistry and cell conditions
- Report on conditioned cell’s microbiology, chemistry, toxicity
- Monitoring — six month reports on flow, water quality and toxicity
- Report on interim results regarding accumulation/mobilization
- Final report, fact sheet and two presentations