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ENGINEER'S INSPECTION REPORT DATE. 8/28:2011 <br />DAM NAME: MOUNT PiSGAH DAM I.D.: 120129 <br />OVERALL CONDITIONS <br />Overall the dam appears to be performing well Main issues are the valves the spillway size and the old outlet conduits. <br />1) Valves: Owner is working on replacing them possibly this fall. <br />21 Spillway Size: Owner's enaineer performed a spillway hydrology study and we recently returned it with comments. We had concerns <br />about the results from our Extreme Precipitation Analysis Tool program We will continue to work with your engineer toward approval of a <br />inflow design flood. <br />3) Old outlet conduits: Short term -- need to monitor seepage closely and monitor for external sians of distress along the old conduit <br />alignment Long term — perform internal inspection if possible and plan to properly abandon the conduits (ex. Grouting). <br />Based on this Safety Inspection and recent file review, the overall condition is determined to be: <br />`7 (71) SATISFACTORY yV (72) CONDITIONALLY SATISFACTORY EJ(73) UNSATISFACTORY <br />O `p <br />M a <br />a <br />o p y O.Y <br />m <br />'A N O q <br />0 t 0 a <br />oF-a`� <br />n 'o ° <br />O q <br />0Wa, <br />w <br />2Loyw <br />a os c <br />41 in a <br />�3 a 0. <br />C <br />-W E a <br />W q <br />N <br />mCt ut <br />QMi;c <br />O -"m <br />a.,2 I th <br />aa'^a <br />a <br />ffia�'a <br />OI q <br />W N a y <br />a 4, S <br />in E ` c <br />'A <br />S % E -9 <br />ITEMS REQUIRING ACTION BY OWNER TO IMPROVE THE SAFETY OF THE DAM I <br />MAINTENANCE - MINOR REPAIR - MONITORING <br />1(80) PROVIDE ADDITIONALRIPRAP: <br />------ ------- --- ----- - --- --- - ----- ------ --- --- -- -------- -- -- - - - --------------------------------------------- <br />(81) LUBRICATE AND OPERATE OUTLET GATES THROUGH FULL CYCLE continue to maintain <br />Q✓ (82) CLEAR TREES AND/OR BRUSH FROM: spillway return channel along downtream toe of dam, upstream slope, and from right & left groin. <br />© (83) INITIATE RODENT CONTROL PROGRAM AND PROPERLY BACKFILL EXISTING HOLES: downstream slope as needed <br />"(84) GRADE CREST TO A UNIFORM ELEVATION WITH DRAINAGE TO THE UPSTREAM SLOPE: <br />❑ (85) PROVIDE SURFACE DRAINAGE FOR: <br />R(86) MONITOR seepage at old outlets. Reset weir & Install staff gage. Fix leak in diversion pipe so seepage can be monitored better. <br />©(87) DEVELOP AND SUBMIT AN EMERGENCY ACTION PLAN: EAP needs to be updated. The copy in our riles is dated 1994. <br />®(e8) OTHER Perform monthly routine monitoring when reservoir is above 112 full. I've enclosed a blank inspection form. <br />©(89) OTHER Monitor dike on right side of spillway and spillway return channel during spillway flows. <br />ENGINEERING - EMPLOY AN ENGINEER EXPERIENCED IN DESIGN AND CONSTRUCTION OF DAMS TO: (Plans and Specifications must be approved by State Engineer prior to construction) <br />®(90) PREPARE PLANS AND SPECIFICATIONS FOR REHABILITATION OF THE DAM: Please provide us with plans and specifications for the valve replacement project. <br />F�(91) PREPARE AS -BUILT DRAWINGS OF: <br />........ -- --- - -- <br />(92) PERFORM A GEOTECHNICAL INVESTIGATION TO EVALUATE THE STABILITY OF THE DAM: <br />Q (93) PERFORM A HYDROLOGIC STUDY TO DETERMINE REQUIRED SPILLWAY SIZE: Returned with comments to your engineer. We will Continue to work with them <br />to approve an inflow design flood. <br />O (94) PREPARE PLANS AND SPECIFICATIONS FOR AN ADEQUATE SPILLWAY. if the hydrology report shows It Is needed. <br />❑ (95) SET UP A MONITORING SYSTEM INCLUDING WORK SHEETS, REDUCED DATA AND GRAPHED RESULTS: <br />Q (98) PERFORM AN INTERNAL INSPECTION OF THE OUTLET: When gates ere Closed. AI80 need t0 inspect intake conduits Upstream Of gate valves &document <br />as -built conditions if different from the old construction drawings (C -2441 ) <br />F�(97) OTHER: <br />❑(98) OTHER: <br />[_�(99) OTHER: <br />SAFE STORAGE LEVEL: RECOMMENDED AS A RESULT OF THIS INSPECTION <br />(101) FULL STORAGE _ FT. BELOW DAM CREST <br />,(102) CONDITIONAL FULL STORAGE - FT. BELOW SPILLWAY CREST <br />F-1(103) RECOMMENDED RESTRICTION 30 - FT. GAGE HEIGHT <br />NO STORAGE - MAINTAIN OUTLET FULLY OPEN <br />(104) CONTINUE EXISTING RESTRICTION <br />REASON FOR RESTRICTION <br />perform reauried maintenance Continue to make progress on valves spillway hydrology, and monitorincl old outlet conduits <br />ACTIONS REQUIRED FOR CONDITIONAL FULL STORAGE <br />l <br />Engineer's /` •' I _ ___ __ � -- /k� - — Signature - f/',�Ir�- ��?s^DATE- <br />Signature % <br />- WNERIOWNER'S REPRESENTATIVE -- = <br />INSPECTED B <br />r <br />Page 4 of 5 <br />