Four Science Projects Receive Awards from North Group

Sue Leskiw

For the 14th year, North Group Sierra Club sponsored awards for the best projects relating to environmental issues at the annual Humboldt County Science Fair, which was held virtually in mid-March. Four cash prizes were awarded. ree of the four projects North Group judges selected competed in the California State Science Fair in April!

“Fecal Matters” by fth-grader Petra Bunz from Gar eld Elementary School in Freshwater was awarded rst prize. Her research question asked “Is there a di erence in fecal contamination levels at upstream and downstream locations in rivers near grazing cattle?” She hypothesized that downstream sites would have higher concentrations of E. coli bacteria. Petra collected water samples from two local rivers with grazing cattle nearby – the Elk and the Little – both at their mouths and as far upstream as she could access. Elk River showed little di erence between the source and the mouth on all three test days, with samples measuring in the “clean” range. Petra was surprised that the mouth samples weren’t contaminated by the many cows she observed along the river. She conjectured that her results could have been a ected by two variables: taking samples during high tide when bay water could have diluted any contamination, or her mouth sampling location could have been near where treated e uent from the Eureka wastewater treatment plant is discharged. Little River showed mixed results, but both upstream and downstream areas tested above the “clean” range on at least two of three sampling dates. Results supported Petra’s hypothesis that there would be more fecal bacteria at the mouth than upstream. However, in no tests did bacteria levels reach the “contaminated” range.

Petra Bunz holding water sample taken from her upstream location on the Little River, 2/21/21

Second place went to Arcata High freshman Alexandra Morris for “Save the Day by Saving the Bay.” e objective of her 3-year study was to determine how an oil spill could be cleaned up with the least damage to the environment. Alexandra focused on absorbing crude oil out of bay water in this nal year of research. She examined whether a less-common method of sopping up oil would be a better approach than those currently used. Alexandra used six absorbents to remove oil from Humboldt Bay water samples: two types of oil-absorbent booms, the commercial product X-Sorb, feathers, peat moss, and hay. She mixed bay water, crude oil, and each test product into large tubs, observed them for an hour, then strained and drained the contents to measure how much oil remained. She found that feathers absorbed the most oil, leaving 5 mL of her starting amount of 125 mL, followed by peat moss (8 mL), hay (20 mL), X-Sorb (45 mL), white boom (60 mL), and blue boom (100 mL). All the non-commercial products she tested absorbed more oil than commercial products, so products currently used on oil spills may not be the most e ective. X-Sorb (the main product used commercially for oil spills) contains chemicals that could be harmful to the surrounding environment, whereas an absorbent such as feathers, found in nature, will not harm the environment. Alexandra was selected to compete at the State level.

Pacific Fisher in an old-growth sampling area.