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It has been an unsually wet spring here in Snohomish, Washington and between the pervasive rainfall, a case of bronchitis, and planned horse trips into the back country; it has taken quite a long time to get our Paragon System up and out of the ground.  But despite all of the delays, we have recently made a good deal of progress.  The following is our journal of significant events that have taken place.

Day 3 – Roger Portman (farm owner) and Ryan Burke (O₂Compost engineer) staked out all of the post locations and dug eight 3-foot deep post holes using a rented auger.  This was a labor intensive process, given that we live in glacial terrain and that rocks in the soil abound.  In addition, the ground water level is near its high point and that four of the eight holes immediately filled with water.   

Once the holes were dug, a bag of ready mix concrete was placed in the bottom of each hole to serve as a solid base. The objective with doing this is to provide a pad to support the bottoms of the posts and minimize short-term and long-term settlement of the structure.

Day 4 – Roger and Ryan wrestled the eight 8-inch by 8-inch posts into position and secured them with bracing.  This was heavy work and both were be glad to see the last post secured. The biggest challenge with this step is to make sure that each post is on-line and vertical.  As you can see in the photo, a good deal of bracing is required to make sure the posts do not move when the concrete is poured.

Day 5 – they built six aeration boxes (two per bin) as part of the concrete form work.  Each box includes a ledge on which to place the slatted floor to spread the airflow evenly across the base of the pile. Each form included a 3-inch diameter hole through which the aeration pipe would extend. The forms were designed to knock out easily after the concrete was poured and allowed to set-up for 24-hours. 

Day 6 – additional crushed rock was brought in to raise grade and provide additional support for the aeration boxes.  The outside forms were also added, making them secure with metal stakes to prevent blow-out from the pressure of the concrete.  In addition, the rebar was added on a prescribed grid pattern.  In this case, the walls will be poured in place concrete that extend between the posts to form three sided bins.  Lastly, the aeration pipes were added, as seen in this photo.

Day 7 (now Day 48 since breaking ground) – the concrete was finally poured – a cause for celebration.  Because of soft ground conditions, a pump truck was used to transfer the concrete from the concrete truck to the aeration slab.  While this cost a bit more, it made it much easier to direct the wet concrete to where it needed to go, thereby greatly reducing the labor of transporting it with a wheelbarrow.  A concrete vibrator was used to make sure the concrete filled in all of the gaps to eliminate air pockets.

Day 8 – 24 hours after the concrete was poured, the forms were removed to reveal an excellent finished concrete slab.  As can be seen in this photo, vertical rebar had been installed immediately after the concrete was poured (while it was still wet) and will be used to connect the pad with the walls.  At this point, the only thing remaining to do with the walls is to form them up and pour the concrete later this week.  Again vacation is coming into play, with Roger and his wife heading off to Europe for a 3-week cruise throughout the Scandinavian Countries.  This will allow plenty of time for the concrete to set up and achieve its maximum strength.

Our next blog will show the finished walls followed by the superstructure and installation of the aeration system.  “Stay Tuned!”