WPCe 2B1RV3|aBits Charter Roman 12pt (HP Roman 8) (Port) (FW)`9hC8,}Ah9> (P@fQXP"5^8DDp(TTd8@8`pppppppppp@@`x|tl@Xxhppx|xxtT`Td(dlXl`@hp88h8pllhLPDpddd\`d`dxddxxddxxxxxxdxddddd|Xt`t`t`t`@8@8@8@8pllllppppxddlllxdxhplddx|x|d|xxxtdxxxhxhxppxxdxxxxxdxxxxxxxlxxxpPNxxxt`dD`XXppxpLPpxxxxxxxxxxddxxxmxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx@lxxdxddddddddx2 Z YcHP LaserJet Series II (Additional)HLSEIIAD.PRSAh9> (P@fQh0$ZXP Progress Report to FEMA on Implementation of Dam Safety %for Fiscal Years 1990 and 1991 )U. S. Geological Survey Introduction 1. Dam Safety responsibility and jurisdiction: The U. S. Geological Survey (USGS) owns and has maintenance responsibility for one low dam and one small concrete topped earthen embankment. Program Actions Since Last Report 1. Actions taken in response to comments and recommendation in Chpt. V, "Conclusions and Recommendations" in National Dam Safety Program1988 and 1989: The USGS maintains the position of Dam Safety Officer. The USGS will inform Interagency Committee on Dam Safety (ICODS) members of any proposed changes in policy or standards should such occur and will strive to adopt uniform standards in accord with ICODS recommendations. 2. Changes in the administration of the dam safety program: The USGS has not implemented a formal dam safety program. The two small dams under USGS jurisdiction are perceived to offer no significant downstream hazard, even in the event of a catastrophic failure. A formal emergency action plan, however, should be prepared and implemented, in compliance with FEMA and ICODS recommendations and guidelines. According to Mr. Ben Raiche, Facilities Manager for the USGS Eros Data Center in Sioux Falls, SD background data on our Sioux Falls dam was provided to an office of the Bureau of Reclamation with the expectation that recommendations for an emergency action program would be provided. Mr Raiche is not currently in possession of any recommendations for a plan, therefore we would like to resubmit our data and make necessary arrangements for assistance in developing a dam safety/emergency action program in compliance with FEMA and other standards. Implementation Progress 1. Adequacy of Dam Safety Organization and Staff: The USGS dam safety organization and staff are considered to be adequate. The Sioux Falls dam is continually inspected and maintained by a trained engineering and maintenance staff. The Reston, Va. embankment has been inspected by USGS Safety Office oersonnel, the USGS Dam Safety Officer, and other earth science professionals at the USGS. 2. Dam Safety training: No dam safety training is currently being performed or supported. No training deficiencies are thought to exist at this time. (0*0*0*Ԍ 3. Status for independent review of design, construction and operation and use of external consultant services: The USGS does not currently engage in the independent review of dam design, construction and operation. The General Services Administration (GSA) is presently providing consultation in regard to shortterm remediation and longterm planning and reconstruction of a small earthfilled dam at USGS Headquarters in Reston, Va. 4. Rehabilitation of dams: The Nolan Pond Dam, located on the western edge of the USGS property in Reston Va. is currently undergoing shortterm repairs and study for permanent rehabilitation by the General Services Administration, Design and Construction Division, Architectural/Structural Section. The need for this rehabilitation was recognized prior to the close of this report period, however, the preliminary survey, analysis and remedial work have been done since Oct. 1, 1991. The Nolan Pond Dam is a small earthen embankment approximately 60 feet in length. Dam height, from crest to the bottom of a drainage culvert located at the downstream base of the dam is estimated at 12 feet. The dam is located on the northwest side of the 105 acre property. Nolan Pond, the impoundment formed by the dam is a catchment basin for runoff from some of the USGS parking lots and some of the roof drainage. The original structure was built in 1972 and has undergone several subsequent modifications, including a concrete cap with a slight spillway depression to accommodate overtopping. The downstream face has been reinforced with 1 to 2 foot riprap, and subsequently sealed with concrete. The concreting of the rock riprap on the downstream face has apparently permitted retention of water and the development of hydraulic pressure behind the downstream face. Conditions of concern observed at the dam are: 1. A cavity under the inlet structure, apparently due to soil erosion. 2. Soil erosion on the south side of the inlet structure. 3. A large cavity, estimated at 2 feet deep, 6 feet long and 5 feet wide, located near the top of the downstream face of the dam and extending under the concreted rock apron. 4. A second large cavity in a grassy area at the base of the downstream side of the dam, estimated at 2x10x4 feet in size. The USGS is evaluating the GSA study report which includes recommendations for shortterm remediation of the dam structure. Also bieng considered is a geotechnical study of the site and possible reconstruction of the entire dam. 5.Agency conducted management effectiveness reviews and GAO reviews: None. (0*0*0*Ԍ6. Dam failures or incidents and followup actions: None. 7. Status of emergency action planning: This is discussed above in Program Actions Since Last Report; (2) "Changes in the administration of the dam safety program." 8. Status of adoption of technical guidance developed by the ICODS: No special plan of adoption of specific guidelines is required for the management of two low hazard dams. 9. Special initiatives to improve the USGS dam safety program: No special initiatives have been undertaken prior to our statement above in this document, under "Changes in the administration of the dam safety program". Data Table *Inspections on the Sioux Falls dam are conducted on a daily basis.