silo 3 - U.S. Department of Energy

Access and Retrieval Strategy for the Silo 3 Project
Document No. 40430-PL-0002, Rev. 1
September 2003
* _. , ’; :
0 I .o INTRODUCTION 5069
This Access and Retrieval Strategy (A&RS) document describes the strategies, systems,
and equipment for accessing and retrieving material from Silo 3. The silo is located at the
U.S. Department of Energy (DOE) Fernald Closure Project (FCP) site in Fernald, Ohio.
Previously, the site has been named the Feed Materials Production Center (FMPC) and the
Fernald Environmental Management Project (FEMP). As part of the remediation of
Operable Unit 4 at the FCP, approximately 5,100 yd3 of byproduct metal oxide materials
stored in Silo 3 will be removed, conditionedltreated, packaged, and transported to an offsite
facility for disposal.
0
0
The A&RS is limited to access and retrieval operations only and is not intended to describe
the subsequent handling, conditioning/treatment, packaging, and transport of the Silo 3
material. These activities are covered in the Process Description for the Silo 3 Project
(FEMP 2003).
1.1 OVERVIEW OF ACCESS AND RETRIEVAL SYSTEMS
1.1.1 PRELIMINARY ACTIVITIES
Access and retrieval of the Silo 3 material will be accomplished by using both pneumatic
and mechanical systems. Before the silo is accessed for retrieval operations, the radon
concentration in the silo headspace will be reduced to an acceptable level. In preparation
for mechanical retrieval, a reinforced concrete framework has been installed on the east
silo wall (during Silo 3 Project construction), and a section of the silo wall will be removed
(after initial pneumatic retrieval operations).
1.1.2 PNEUMATIC RETRIEVAL SYSTEM
x.
Pneumatic retrieval involves vacuuming material through the existing man ways on the
Silo 3 dome. The system is used to remove flowable material in a controlled manner from
top to bottom and from behind the silo wall before creating the wall opening. The
Pneumatic Retrieval System (PRS) transfers the material to the Process Building, where the
material is conditionedhreated and packaged. The PRS will be operated initially since the
material height is into the dome space.
1.1.3 MECHANICAL RETRIEVAL SYSTEM
In addition to pneumatic retrieval, a Mechanical Retrieval System (MRS) is used to access
and remove the compacted material from Silo 3. A mechanical excavator transfers Silo 3
material to a bin located in the Excavator Room. An inclined belt conveyor feeds the
material to the Process Building.
It is also expected that the excavator will be used as necessary to manipulate a vacuum
wand end effector to retrieve material using the PRS. The excavator can also be used
specifically to loosen compacted material, which then could be vacuumed by the PRS
vacuum wands located inside the silo.