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• 1981 Uncertainty about the Lazard classification prompted more detailed study. After reevaluation, the hazard classification was changed to "moderate" or Qass IL The ?.may Corp of Engineers was informed of the change and the structure was removed from them list of unsafe "]righ Lazard" dams. 1983 Based on the results of field investigations and stability analysis, the owners were provided additional recommendations and advised tbe restriction would remainin effect Repairs to the dam would Lave to include: Constmction of a spillway to meet dent design standards • Perfamz slaln7iry analysis of the embankment • Modify tbe shucture as required based on Ute stability analysis results • Investigate underground coal nrining activities in the azea which may also affect safety of the dam • Perform an internal inspection of the outlet 1984 With the outlet's Limited capacity, the reservom wind not be controlled at the restriction level during unusually lrigh Spring nmoff Daily inspections of the dam were perfotmerl Wahl the maoff subsided and the reservon- lowered to the restriction level Because of delays in making repairs, safety cancans remained at issue. The inability >fl wntrol the reservoir level drning periods of above nom rtmoff incessantly cLaliertged the effectiveness of a storage resmction. As a result the owffir was intaamed tbe spillway nmstbe excavated to the restricted level, 10 Beet below the dam crest Delays doe to weather and in Forest Service approval Prev®ted wmpletion of ttre regtmed spillway excavafiain. As a result the restriction was increased la 15 feet below the dam crest to provide additional storage during xnnoff • 1985 During a mutime anmtal safety inspection of the dam a crack an the embankment was observed begi~g at the left abutmerrt and egg 100 feet along tbe cede of the crest The crack was 125 inr~s wide and about 2 feet deep. Ano&or crack was observed on 11te downstream face, measa®g 15 feet long in the straps of an arc. Water level is the reservoir at the time of inspection was 1 foot below the spiIIway crest because of unwt>aCy Ligh Spring ~ff The owlet was open fully in wmpli~ce wi9lrpravisiom: of the resection. Investigations were undertaken in late Smmner The cracks were ecavated to dete®ine the depth and extent White paint was poured into /Le surface pace fA improve visrbility of the vertical extent of aacl~mg dining excavation. Cracks vrae traced to a dept of about seven feet 1Be excavation resah5ed in a teach across the downstream shell of the dam, extending from the le$ abntmeot for a distance of aborrt 130 fcet and 29 feet deep. The embankment fill material was very wet near the abuUment wnhact Becaau of the Irigh level of saturation, ~a dram was installed at Ste botNm of the excavation befine backfi}Img. The sprlway was also eacavabed 5 fiat Iowa, resulting in a total freeboard of 10 feet After completion of the drain and spillway excavation, the restriction was revised to 1 foot below spill Provisions of the restriction regn¢ed weekly inspection and monitoring ofll>c dam be perfo~td when the reservoir level was wifitm 5 Beet of spill 1986 Dmiag Spring rmuo$ tLa reservoir mould not be wNCOlled at Ste restriction level by 9re orHlet and again spilled as in Ste two previeasyearg. D~ as inspection of the dam, a 1 inch wide crack was observed diagotmlly across the spiIIway cLa>mel, 20 feet downstream offfie emrance. The aadc exmbited vortical displacement of 2 inches dowawdrd on tbe lpsJzeem side. Tls hate a tqr the left bank of ~ spr7lway clta~l, across the road, and disappeazed itrto 8re brash on the hilLtide above Ste dam. 1987 Tn eazly Lune, the access road in the dam was destroyed overnight by a landslide OS miles downstream Several days passed before the main access mad could be restored. •