
Do you have a back-up plan??????
During the wet weather you need an alternate plan when trenching.
Why do you ask?
Because water can turn an “A” type soil into a “C” type soil very quickly,
(read our previous post on soil types)
What is your back-up plan?
Use a Trench Box!
How do I use a Trench Box you ask!
Here are the instructions….
· Make sure your trench box is 2 ft. or less from the bottom of your trench.
· Make sure you have 18 inches of freeboard from the top of the trench to the top of your trench box.
· Calculate your slope by measuring from the bottom of the freeboard of your trench box.
· The slope will need to be 34 degrees from horizontal.
What are the signs that my soil type is changing?
· The soil wall starts oozing water out of the vertical wall of the trench.
· There is water in the bottom of the trench.
· There are chunks of soil breaking away from the vertical wall.
Remember: Most soils will change to a type “C” soil very quickly once water is introduced.
The most important safety tip I can share with you is this:
When working with type “C” soil sloping begins at the bottom of the trench. There is no vertical wall.
Do not measure for slope any other way!