WPC  2"BR ZpX#|TArial ItalicArialArial BoldHP LaserJet 4 PlusIIHPLA4PLU.PRS2xCQ\'sZX 9ND,C2xjAG;X 1mC9,  Xm2PG;XP/qC:,cXq2pPG;X2n T|TOO "4^DDV6OOYAOAADDAwDADn6wD66w6RwDwwwuR?ROAnOOODOOOOOOuOAwCCCCCCCCwwwwwwA6AAA6AAgww6A6[6RRRwwwwTDDwuuu6RwDwwDu414WddddddddddddddddddddddddddddddddddddddddNTT~PYVPTO33PPPPTTyuu3OuO"uu~uu"m+^99Ipp.DDNt9D99pppppppppp99tttp̅}9ep}}999\p.ppepp9pp..e.ppppDe9peeeeE5EtD9sZDDD9DDDDDDpD|9pppppȰepppp99999999pppppppppepp|pepppppeeee|pppppppppppp9.999.99Xeep.p:p.pDp.pxppppȼDDDeeee}L}9}9ppppppe}e}e}epp.pDe}9ee|pp8dp,(,WddddddddddddddddddddddddddddddddddddddddNHxxHlpD|pppppLJpDHpD,,DDpDDxppxHxxHsdd,DdD"dxdldtxxd"m+^:D`pp8DDLt8D88ppppppppppDDttt|Đ|8p|||D8Dtp8p|p|pD||88p8||||LpD|pppdL8LtD8ttDDD8DDDDDDpD|8pppppȰppppp88888888|||||||||pp|||p||ppppppppppp||||||||88888888ppp|8|L|8|`|8|||||ȼLLLpppp|`|D|D||||||p|d|d|d||8|Lp|Dpp||:dp,0,WddddddddddddddddddddddddddddddddddddddddNHxxHppD|pppppLHpDPpD88ddpDDxppxHxxHs||8ddD"dxxldtxxd2  P #Xm2P XP#e  yxdddy Jicarilla Lajara|'`v(#5Conceptual Design   I.XEXECUTIVE SUMMARY (# XThe LaJara Lake Dam is owned and operated by the Jicarilla Apache Tribe (Tribe). LaJara Lake Dam has been identified as unsafe by the Bureau of Reclamation (BOR) under the Safety of Dams program for the Bureau of Indian Affairs (BIA). LaJara Lake Dam is classified as a high hazard dam.(#  XIn September, 1992 the Tribe retained the BenhamHolway Power Group (BHPG) to perform the following scope of work:(#  R 1.` ` Investigate the safety of LaJara Dam and verify suspected deficiencies.(#`  R 2.` ` Perform feasibility studies of a wide variety of potential remedial measures.(#`  R\ 3.` ` Perform more detailed conceptual design studies of a limited number of preferred remedial measures.(#`  R 4.` ` Design and supervise installation of remedial measures selected. (#` XLaJara Dam was extensively investigated and analyzed (number 1 from above) resulting in a Deficiency Verification Analysis (DVA) report. The conclusions of the DVA classify LaJara dam as "Unsatisfactory" as defined in the Indian Dams Safety Act of 1994, P.L. 103302August 23, 1994. Interim measures have been implemented to provide early warning for piping failure and normal event overtopping. These measures if used properly result in changing the classification to "Poor". The Feasibility Design Report (number 2 from above) has been completed and the results were used to develop the conceptual design report.(# XThe purpose of this report is to further develop the conclusions and recommendations of the feasibility study and to recommend remedial measures for final design. After these conceptual designs have been reviewed by the Tribe and the preferred alternatives have been determined, final designs will be prepared.(# (,))ԌXSection II of this report gives the purpose of the report and a general description of the existing dam and deficiencies of the existing dam. Section III discusses the hydraulic and hydrologic loading criteria and develops the conceptual design hydraulic improvements. Section IV discusses the geotechnical/embankment design criteria and develops the conceptual design geotechnical improvements. Section V discusses the structural design criteria. Section VI discusses important construction aspects associated with the different remedial measures. Section VII discusses environmental consequences of the remediation alternatives. Section VIII lists the conceptual design alternatives to consider for final design. Section IX evaluates the conceptual design alternatives on the basis of constructability and cost. Section X determines the alternative recommended for final design.(# XThe recommended alternative for final design is Alternative 3 which is shown on drawing LX222. The hydraulic improvements included in this alternative are as follows: (1) provide roller compacted concrete (RCC) protection for the downstream slope and crest to permit overtopping of the dam, (2) add fusegates and the diversion dike emergency spillway, (3) repair the existing corrugated galvanized metal pipe (CGMP) structures under State Highway 537 and remove potential falling rock from the bluff, and (4) replace the outlet works. The geotechnical improvements included in this structure are as follows: (1) provide an all weather surface crest, (2) provide RCC on upstream slope from crest to normal water level and dumped rock from normal water line to upstream toe, and (3) provide a downstream toe drain, 40 foot RCC apron, and 20 foot riprapped stilling basin.(#