What should be kept as a copy from the log?

Gauge calibration parameters are essential records that should be retained from the log because they ensure accurate measurements and quality control in earthwork projects. Calibration parameters provide documentation of the precision of measuring instruments used on site, which is critical for maintaining standards and ensuring that work is performed according to specifications. Keeping these records helps in tracking equipment accuracy over time, assisting in troubleshooting and maintenance, and providing a reference for verifying the quality of the work completed.

In contrast, daily work summaries, material safety data sheets, and incident reports, while important, serve different purposes. Daily work summaries document activity on the job site, material safety data sheets provide information on handling hazardous materials, and incident reports record any accidents or safety issues. These documents are essential for various operations and regulatory compliance but are not the primary focus regarding calibration and measurement integrity.