by Tony Heath, Project Engineer

This post covers Thursday, August 15.

Howdy! Today was a big day at the garden: the soil mix is here!

The Landscape Recycling Center (LRC) delivered the bioretention soil mix backfill for the south cell. LRC started delivering the soil mix slightly before 8:00 a.m. while Facilities & Services’ Josh and Stephanie finished up with the last section of bike path removal. Delivering the soil to the site took the majority of the day and required more than 14 truck loads.

Around 9:00 a.m., the bike path removal was complete and work refocused to spreading the soil throughout the south cell. It was an imperfect science but we tried to install the soil in 8″ lifts to meet our 24″ amended soil depth across the entirety of the cell.

8″ lift installation to achieve 24″ depth. Photo by Tony Heath.

During the soil mix backfill installation, we ensured to minimize compaction as much as possible. To that end, Stephanie used a tooth bucket to spread the soil instead of the grade bucket. Further, she carefully positioned the backhoe outside of the rain garden’s perimeter to avoid compaction in the cell from the heavy equipment. These precautions made installation slow going despite the soil mix being easy to work with. Nevertheless, the time and care taken now is worth it to ensure infiltration performance in the long run.

At the end of the day, we used hand tools to work the soil into the corners and other places hard to reach with the backhoe. Soil mix installation took most of the day, but we got everything done!

I’m out of town on Friday but look forward to being back to the site on Monday.