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City of Orono – Orono Public Works Facility, Orono, MN AET Proposal No. P-0012042 September 15, 2022 Page 7 of 10 Bituminous Subgrade Test-Roll Observations and Testing During or after final grading of the pavement subgrade soils, AET personnel will observe test-rolling of the pavement subgrade soils. These observations will be performed by an Engineering Assistant on an on-call basis. Our scope of services will include the following:  Observe the reaction/stability of the pavement subgrade soils as they are test-rolled by a loaded, tandem-axle dump truck.  Evaluate the subgrade deflections under the wheel loads, and mark areas of excessive deflection. Areas of excessive deflection will be shown to personnel from the contractor and/or their subcontractors.  Provide recommendations for correction of the unstable subgrade soils. After placement of the Class 5 aggregate base, an Engineering Technician II from our firm will test the compaction of these materials using the nuclear density gauge method, or by performing DCP testing. The nuclear density gauge test results will be compared to the Standard Proctor maximum dry density. We estimate 2 trips will be required to complete the test-roll observations of the pavement subgrades and 2 trips will be required for aggregate base compaction testing services. Bituminous Observations and Testing When placement of the bituminous base and wear layers begins, an experienced Engineering Technician II will make site visits on an on-call to observe the placement and rolling of the bituminous layers and to perform testing of the bituminous. The technician will perform the following services:  Measure the temperature of the bituminous as it is placed and while it is being rolled.  Measure the thickness of the bituminous layer while it is being rolled.  Help to establish a rolling pattern each day by observing the number of passes the roller makes over the bituminous, and measuring the density of the bituminous during the rolling to evaluate how many passes are needed to reach the maximum density.  Obtain samples of the bituminous for laboratory testing. We assume the paving will be performed in 2 lifts and assume that 3 trips will be performed by our Engineering Technician II for the above referenced observation and sampling services. The samples retrieved from the site will be tested in our laboratory for MnDOT Gyratory properties, including:  Gyratory density, Rice specific gravity, Asphalt Film Thickness (AFT), Coarse Aggregate Angularity (CAA), and Fine Aggregate Angularity (FAA).