New Austrian Tunnelling Method called Sprayed Concrete Lining.

A local community defined by physical boundaries or social similarity. Boundaries may not be precisely defined

Laborer on the drilling crew who handles drill steel replacements and bits and does general housekeeping.

Oxides of nitrogen. Common pollutants monitored in urban areas. Work has been directed at understanding the total cost to society of the release of such pollutants

Unwelcome sound

Sounds or sound levels causing annoyance, environmental or health impacts

The failure to meet a specified standard.

Full-circle or arch forms that when stripped and collapsed, will not pass through other forms erected in place.

Pollutant and dangerous smoke produced in the construction site.

Attachment at end of delivery hose from which shotcrete is jetted at high velocity

Worker on shotcrete crew who manipulates the nozzle, controls consistency with the dry process, and controls final disposition of the material