A three-storey mixed-use building on North Front Street hit refusal at less than two metres during preliminary exploration. The contractor had assumed competent limestone but instead encountered dense glacial till with nested cobbles—classic Belleville subsurface. Standard Penetration Testing sorted it out fast. SPT remains the backbone of site investigation across southeastern Ontario because it delivers a blow count and a sample in one go. For projects along the Moira River or up toward the 401 corridor, the test cuts through guesswork when overburden stratigraphy is erratic. We run the SPT rig on truck-mounted or track-mounted setups depending on access, and we log every six-inch increment so the geotechnical engineer gets a profile that stands up to NBCC 2020 and Ontario Building Code review. Pairing the SPT with grain-size analysis helps distinguish a well-graded till from a silty sand lens—critical when bearing capacity varies across a single building footprint.
SPT N-values in Belleville’s glacial till often jump from 8 to refusal within a single drive—that transition defines the bearing stratum.
