Letter from the Chief on Flyrock

• Posted on Jul 27, 2020

Letter from The Chief

Dear Eastern PA ISEE Newsletter readers,

Flyrock is an inherent risk of blasting, but is preventable. It does not have to happen. When it does occur there is a lot of effort by the blasting contractor, the permittee and DEP to find out why it happened and how to prevent it from happening again. Current blast records and widespread videotaping of blasts are critical for these efforts to succeed. These days most flyrock incidents are not caused by basic blast design errors such as too little stemming, boreholes too large for hole depths or burdens and spacings being too large or small. Most of the flyrock incidents that have occurred recently have been due to precautions not being taken to address conditions in the rock being blasted.

Quarry faces are often uneven which requires bore tracking and face profiling. Careful drilling with appropriate drilling equipment for the site conditions are a must as are detailed drill logs, so the blaster is aware of any changes in the rock. On construction blasting operations one of the biggest problems is inconsistent rock. Care must be taken to ensure that the blaster knows the extent and condition of the rock surrounding each and every borehole.

Blasting is an ultrahazardous activity and is regulated as such. Flyrock is prohibited. Flyrock is a serious violation and appropriate enforcement action will be taken in each case. All blasting in PA must be authorized by DEP permits. The activities conducted on those permits should not be a danger to the public or their property.

When designing blasts please be careful to include any measures that will prevent flyrock. We have been very fortunate to not have a flyrock fatality in PA since 1999. However, there have been several incidents in the past few years where there was potential for injury or worse. Added precautions will help to ensure flyrock incidents do not occur.

Please stay safe and stay healthy,

Richard Lamkie