Quarry monitors report 18 blasts in Q1; all readings stayed below PDD limits, consultants say

Franklin City’s Quarry Monitoring Committee on April 22 reviewed first-quarter monitoring from Stantec Consulting Services showing 18 controlled blasts, one formal complaint and no exceedances of the Plan Development District’s (PDD) vibration or decibel limits.

Stantec consultant Kristin (last name not specified) told the committee that during January–March the firm completed two observation events and that “there were a total of 18 blasting events and only 22 percent of them were confirmed by our monitors,” a gap the consultant said was partly due to monitor locations. She said the PDD requires that 85% of blasts for a calendar year fall below permitted levels, and that during the quarter “there were no blast events that were above the vibration limit and there were no blasts that were above the decibel limit.”

The consultant reported one formal complaint about vibration and noise from a March 4 blast; the complainant’s location was identified as south of Drexel Avenue and described the event as “it felt like a rolling blast.” No anonymous complaints or non-blast dust complaints were logged for the quarter.

Payne and Dolan representatives explained they plan to relocate some of their permanent seismographs during the company’s regular annual calibration in early May to reflect where the active blasting now occurs. Payne and Dolan land resources manager Clint Wenninger said the quarry currently has “4, permanent seismic graphs” and that blasting activity has shifted toward the quarry’s southeast corner; relocating the monitors, he said, will “better represent the actual blasting that’s going on.” Stantec and the quarry agreed to coordinate moves so the city’s monitor and the quarry’s units provide useful verification data.

Committee members discussed the value of keeping multiple, co-located monitors versus moving them to new positions. A committee member noted that the co-located monitors have been helpful for cross-checking readings and for investigating complaints, and Kristin said she would check whether one Stantec monitor could remain at its current 50 First Street location while other monitors are moved.

The committee moved to accept and place the report on file. The motion passed on a voice vote with no recorded opposition.

The presentation and discussion included maps showing complaint locations and the distribution of recent blasts; Stantec said the drawing confirmed most blasting during the quarter occurred in the central and southern parts of the quarry.

Upcoming: the committee was told an announced inspection was scheduled for the afternoon after the meeting, and Stantec will include any subsequent findings in the next quarterly report.