REG NASA-LLIS-0932-2001 Lessons Learned Configuration Control for Underground Utilities.pdf

1、Lessons Learned Entry: 0932Lesson Info:a71 Lesson Number: 0932a71 Lesson Date: 2001-03-21a71 Submitting Organization: KSCa71 Submitted by: Daniel TweedSubject: Configuration Control for Underground Utilities Description of Driving Event: On January 7, 2001, a large washout was discovered in the vici

2、nity of Facility K7-1205F at the Kennedy Space Center Press Site. Water was flowing from the open end of a failed 4“ potable water main. The washout undermined portions of the concrete foundation and driveway apron for a garage canopy at K7-1205F and damaged the sewer and electric services to the fa

3、cility.The dominant root cause of this mishap was the removal of a concrete thrust block from the end of the 4“ water main during installation of a power conduit by a KSC support contractor. The thrust block was mistaken for waste concrete material. With the removal of the thrust block, used as the

4、primary constraint for the direct buried slip joint piping system, there was insufficient contact area with the soil to prevent the water main from separating at the joints.Lesson(s) Learned: The Mishap Investigation Board learned that thrust blocks at KSC are not documented or identified in a manne

5、r which would enable utility locators to locate them, and that modifications to non-configured systems are often performed using engineering sketches that are not typically incorporated into master planning drawings. For underground utilities, this results in some installations that are not adequate

6、ly documented.Recommendation(s): 1. Thrust blocks should be documented as integral components of underground piping systems, and design agencies should update their specifications to provide for positive identification of all new underground thrust blocks from ground level.2. Excavation control proc

7、esses should be reviewed and revised as necessary to incorporate the Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-identification of known and probable thrust block locations when utility locators identify underground piping systems.3. Facility man

8、agement organizations should review configuration management processes and revise them as necessary to ensure that all underground utility modifications are documented (as-built) and incorporated into appropriate master planning documentation.Evidence of Recurrence Control Effectiveness: N/ADocument

9、s Related to Lesson: N/AMission Directorate(s): a71 Exploration Systemsa71 Sciencea71 Space Operationsa71 Aeronautics ResearchAdditional Key Phrase(s): a71 Configuration Managementa71 FacilitiesAdditional Info: Approval Info: a71 Approval Date: 2001-03-26a71 Approval Name: Eric Raynora71 Approval Organization: QSa71 Approval Phone Number: 202-358-4738Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-