Cement-asbestos duct

[krockster]

I am involved in a medium voltage transformer/switchgear replacement project that involves two existing underground duct banks between the outdoor transformers and the indoor switchgear. According to available record drawings (noted as "AS BUILT") the duct banks are reinforced concrete with 4-way, 4-inch cement-asbestos ducts. The installation dates from the early 1970's. I proposed to replace the duct banks, but the Owner wants to know why they can't be reused. Even if they weren't cement-asbestos I would be reluctant to reuse them, as there is no way to ascertain the condition of the ducts while they are in use. If we were to try to reuse them I imagine this would become a remediation project, as the existing conductors are pulled out along with asbestos fibers. My preference would be to install a new duct bank adjacent to each of the existing ones, and plug the existing ones with concrete and abandon them in place.

Does anyone have any experience with reusing cement-asbestos ducts, and can anyone offer additional convincing arguments against it?

 

[7anoter4]

The use of asbestos-cement is prohibited by OSHA and other regulations.

http://www.soysa.org.uk/ppmeetings/ASBESTOS PRESENTATION.doc

http://www.osha.gov/OshDoc/data_AsbestosFacts/asbestos-factsheet.pdf

 

[burnt2x]

Amen. Agree with 7anoter4.