Rock hauled from the M-648 rock cut at Maple Bend

Sources

• Blast_Plans_Drill_Logs_Shots_01-52.pdfBlast plan and drill log for each shot: stations, drilled area, bench height, neat-line volume and overburden depth per hole104 pages
• Blast_Reports_M-648_2026.pdfBlaster’s report for each shot, used for shot number, date and location52 pages
• Scale_Tickets_Maple_Bend_Yard_2026.xlsxExport from the truck scale at the Maple Bend crushing yard: ticket number, date, time, truck, net tons and source7,129 rows
• Daily_Reports_M-648_Apr-Sep_2026.pdfSuperintendent’s daily reports with loads hauled per shot; June 8–12 missing224 pages
• Cross_Sections_Rock_Excavation_Sta_27+50-45+00.pdfCross sections every 50 ft with the rock excavation payment lines36 sections
• Engineer_Letter_Rock_Excavation_Quantity_2026-10-16.pdfThe Engineer’s request to substantiate the rock excavation overrun by cross section2 pages

Method

1. Each shot was identified by its number in the blast plan and the blast report. Stations, drilled area, average bench height and neat-line volume were taken from the blast plan.
2. Loads per day and shot in the daily reports were matched to that day’s scale tickets in weighing order. Where the report gives a load count per shot, the link counts as documented. Where it gives only the time the loader moved to the next shot, tickets are assigned by weigh time less 15 minutes of haul time and count as indirect.
3. Loads with no ticket, while the scale was down on May 19–20, were converted at 22 CY loose per load and a swell factor of 1.55.
4. Weighed tons were converted to in-place volume at the selected density and compared with the blast-plan volume. A ratio between 0.95 and the selected upper limit is treated as consistent with overbreak. Shots where the daily report says soil and shot rock were loaded together are not treated as documented, whatever the ratio.
5. Each shot’s length was allocated to the 50-ft cross-section intervals. Only shots lying entirely within one interval give a documented volume by cross section. All other shares are calculated.
6. For the week of June 8, the shots fired before or during that week whose reported loads do not cover their blast-plan volume form one group. That week’s tickets are compared with the group’s combined volume.

Assumptions and limitations

• The contract is assumed to use the MDOT 2020 Standard Specifications for Construction as modified by the project special provisions. Under subsection 205.04.C, the Engineer measures Excavation, Rock (paid per cubic yard) by the staked-section method to the plan or Engineer-approved cross section, with no allowance for overbreak, and measures overburden as Excavation, Earth. Scale tickets do not replace that measurement, but they show that the rock was broken and hauled. The 0.95 lower bound and the upper limit of the ratio are this review’s own plausibility check, not a contract tolerance.
• The top of rock exists only in the drill logs, because the stripped rock surface was not surveyed before drilling. Subsection 205.03.B requires the rock surface to be exposed so the Engineer can measure it before rock excavation starts, so the missing survey is itself a gap the Engineer can point to.
• Per the daily reports, all shot rock was hauled to the crushing yard. None was placed directly in embankment.
• The density of 2.23 tons/CY in place and the swell factor of 1.55 are assumed for granite gneiss. Check them against the project’s geotechnical report.
• Bench height is assumed uniform along each shot when volume is allocated to cross sections.