Geo-technical Report - PL and LL

During today’s “Soil Analysis” workshop with Coach Jason Pieper, we were reviewing plastic limits (PL) and liquid limits (LL) (Part 2 question #10) from a geotechnical report. Interestingly, the Liquid and Plastic Limits Test Report indicates testing of PL and LL for certain boring sites, but doesn’t indicate PL and LL when reviewing the site specific boring log. For example, B3 indicated PL and LL on the Testing report but not on B3 detailed boring log. Shouldn’t both the testing report and the boring log shows the same information? Why would the information on the testing report different from the boring log?

(Side note: was trying to tag Coach Jason Pieper, but couldn’t find his name under the tag drop down menu)

Hey @mmcandy21,

Great question! Let me see if I can ping Coach Jason to respond. Sorry for this technical difficulty!

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@mmcandy21, thank you for the question. After discussing the question with our geotech engineers, we have concluded that the boring log provided by Engeo for B3 contains a mistake. Although the boring log contains several bits of information, this is compiled by the geotechnical engineer from the reports, and may be subject to human error. The best place to find the PL and LL information is in the “Liquid and Plastic Limits Report” (p. 79) as this will represent the primary source of the information given to the engineers.