January 23, 2004  


Excavation Clearance Form: What is it All About?

By Eva Dusek

If you have ever done excavation work at SLAC, you are probably familiar with the Excavation Clearance Form. The form, along with instructions and background information, can be found on the Web at: http://www.slac.stanford.edu/esh/forms.html

The Excavation Clearance Form helps you complete your project safely and protect the environment during excavation work. It is required for all excavation projects at the Lab.

Fill It Out Before You Dig

One of the greatest hazards during excavation work is accidental contact with utility lines. When you submit an Excavation Clearance Form, the Mechanical Design-Facility Design Services (MD-FDS) group completes the Utility Survey section and provides you with maps of all documented underground utilities that are in your excavation area. Because locations of utilities shown on maps are approximate, a utility line locator may also need to locate and mark utilities in the field. MD-FDS can assist you with this process by arranging for a private locator to come on site to locate and mark utilities in your excavation area.

Protect Yourself from Things You Cannot See

Potentially harmful chemicals ranging from metals such as lead to oils and solvents may be in the soil where you will be working. It is important to know what kinds of chemicals you might encounter so that you can protect yourself and your co-workers. Excavated materials should also be managed properly to protect the air and nearby streams. The Chemical Survey portion of the form gives information to help protect both workers and the environment.

SLAC’s high energy physics research results in radiologically activated materials. In areas where activated soil or other materials could be encountered during excavation, please pay special attention to recommendations provided in the Radiological Survey portion of the form. SLAC has several miles of underground tunnels that are covered with at least 25 feet of soil to shield humans and animals from radiation generated within the tunnels. If your excavation area is near one of these tunnels, it will be important for you to pay special attention to the Radiation Safety Survey Beam Lines portion of the form.

Timely Tips

•Be sure to indicate on the form exactly where you plan to dig and the depth to which you will dig.

• Review the comments on the form so that you can protect yourself, workers and the environment.

• Remember to have the form at the worksite during excavation work.

• Submit a new form if the limits of your excavation expand or deepen.

Contact Eva Dusek (Ext. 3025) or Mike Hug (Ext. 4042) with any questions or comments about the Excavation Clearance Program.


The Stanford Linear Accelerator Center is managed by Stanford University for the US Department of Energy

Last update Friday January 30, 2004 by Kathy B