The
Jefferson County Environmental Services Department (JCESD)
retained the services of the Tetra Tech Project Team to evaluate
92,000 linear feet of reinforced concrete pipe (RCP) known
as the Shades Valley Transfer Interceptor. The gravity interceptor
that was installed in 1987 consists of RCP ranging in sizes
from 36 inch to 72 inch. The pipe was designed to carry pretreated
wastewater flow from the Scott’s
Branch Pretreatment Facility to the Valley Creek WWTP. In addition,
several gravity sewer and forcemains connect to the Shades
Valley Transfer Line along the way to the Valley Creek facility.
The
focus of the presentation will be to explain the process
to effectively evaluate reinforced concrete pipe that has
experienced exposure to hydrogen sulfide corrosion. The process
will consist of developing a condition assessment which is
based on a Corrosion Risk Assessment Analysis. This will
then be used to developed a detailed pipe inspection plan
that can consist of manned and unmanned pipe inspection using
advanced technology such as pipe scanning and sonar. In addition,
techniques will presented for evaluating field data that
will be used to determine a remaining pipe service life in
order to recommend the type and timing of pipe rehabilitation.
Also, a corrosion model will be demonstrated to effectively
predict long term effects of corrosion and remaining pipe
service life. |
