DC Cook Turbine Components

The Challenge

When the Donald C. Cook Nuclear Plant (D.C. Cook) in Lake Township, MI replaced its turbines and corresponding outer casings — which were close to 91 meters in length — disposing of the obsolete turbines demanded a unique but crucial decontamination process.

The major hurdle was determining a feasible method of transporting 687,192-kilograms of turbine components to UniTech’s Oak Ridge, TN service center, thus eliminating the typical utility planning required before on-site turbine decontamination can commence.

The Solution: Shipment

D.C. Cook’s large turbine components were too heavy for long-distance trucking and took up considerable space, but required shipment to UniTech’s Oak Ridge Service Center for off-site processing, decontamination, and final disposition.

Barnhart Crane & Rigging partnered with UniTech and D.C. Cook, shipping turbine components by barge to the newly reopened Oak Ridge barge access area via the Mississippi, Ohio, and Tennessee navigable river systems.

Turbine components were welded to the barge for continuous stability throughout travel. The barge departed from St. Joseph, MI on Sunday, Sept. 10, 2017 and arrived at the Oak Ridge barge area in the early morning hours on Wednesday, Sept. 27 after seventeen and a half days in transit.

The Solution: Receiving

Crews spent the ensuing two days draining the barge water, breaking welds, and setting up cranes for land transportation. It took two full days to unload and stage all six turbine casings from the barge and prepare for trucking to UniTech’s Oak Ridge Service Center. The barge was free released, and departed on Oct. 1. Over the next two days, upper turbine casings were trekked to UniTech’s facility, just five kilometers away, at a cautious pace of 1.6 kilometers per hour, not including the movement of powerlines. Inner casings were received, decontaminated, and cut for recycling within a 72-hour timespan, completed by 2:30 a.m. on Oct. 5.

Shipment of the lower casing components from the dock to UniTech’s Oak Ridge Service Center was delayed when removal of blade carriers posed a risk of crane shock. Delay in shipment to the service center also caused the project to run into fall outage season, a high-volume stretch of time for UniTech’s Oak Ridge facility, which necessitated special off-site storage considerations. Processing of lower casings began on Oct. 10 and finished on Nov. 15.

The Solution: Processing

Once received at the Oak Ridge facility, UniTech processed a total of six casings:

Description	Qty	Length (m)	Width (m)	Height (m)	Mass (kg)
Inner Casing A – Upper Half	1	9,347	5.004	3.607	70,306.817
Inner Casing B –Upper Half	1	9,347	5.004	3.607	70,306.817
Inner Casing B –Upper Half	1	9,347	5.004	3.607	70,306.817
Lower Casing A w/ Blade Carrier & Shipping Frame	1	9,347	6.299	4.572	158,757.33
Lower Casing B w/ Blade Carrier & Shipping Frame	1	9,347	6.299	4.572	158,757.33
Lower Casing C w/ Blade Carrier & Shipping Frame	1	9,347	6.299	4.572	158,757.33

 

For the D.C. Cook turbine decontamination project, UniTech utilized both standard and specialized monitoring processes.

A unique Gamma Spectroscopy process was utilized to verify decontamination of inaccessible areas, and used as a basis of validation for free release survey documentary.

Within 48 days, 687,192 kilograms of turbine components were processed and invoiced for services. Zero percent of material was disposed as low-level radioactive waste (LLRW); 659,977 kilograms of material (97 percent) was recycled during final disposition; and 20,412 kilograms (3 percent) of material was free released to a Tennessee-approved low-level contamination landfill.

Segmentation was very important to this project in particular, with nearly all materials being prepped for recycling.