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Home My WebLink About4.10 Schaefer Ranch GHAD CITY CLERK File # 360-60 AGENDA STATEMENT CITY COUNCIL MEETING DATE: November 7,2006 SUBJECT: Resolution Setting a Public Hearing on the Formation of the Schaefer Ranch Geologic Hazard Abatement District Report Prepared by Frank Navarro, Senior Civil Engineer ATTACHMENTS: Resolution Setting a Public Hearing on the Formation of the Schaefer Ranch Geologic Hazard Abatement District, together with: Exhibit "A" to the Resolution, Petition For Formation (including Exhibit "A" to the Petition, Boundary Map, Exhibit "B" to the Petition, Legal Description, and Exhibit "c" to the Petition, Plan of Control), and Exhibit "B" to the Resolution, Notice of Public Hearing ~'AdoPt the Resolution Setting a Public Hearing on the Formation of the Schaefer Ranch Geologic Hazard Abatement District. RECOMMENDATION: FINANCIAL STATEMENT: There is no immediate fiscal impact. Once the Schaefer Ranch Geologic Hazard Abatement District ("Schaefer Ranch GHAD") has been formed and a funding mechanism has been approved by the Board of Directors and affected property owners, the costs associated with the operation of the Schaefer Ranch GHAD will be offset by assessments paid by property owners within the District. DESCRIPTION: Division 17 of the California Public Resources Code establishes legal standards for geologic hazard abatement district ("GHAD") formation, GHAD financing and the scope of GHAD authority (Section 26500 et seq.). California Public Resources Code S 26550.5 provides that proceedings for the formation of a new GHAD may be initiated by a petition signed by owners of at least ten percent (10%) of the real property to be included within the proposed district. ------------------------------------------------------------------------------------------------------------- COpy TO: ITEM NO. 'tIO ,'\ V Page 10f2 G:\DEVELOP\Schaefer Ranch\GHAD Formation\agst Schaefer Ranch GHAD Formation 11 0706.DOC The Schaefer Ranch GHAD annexation petition has been executed and submitted to the City Council of the City of Dublin. The adoption of the resolution setting a public hearing on the formation of the Schaefer Ranch GHAD is the first step in the formation process. ANALYSIS: Under the Public Resources Code, the City Council must adopt a resolution setting a public hearing and noticing by mail the owners of real property to be included within the Schaefer Ranch GHAD at least twenty (20) days before the date set for the hearing. Property owners may thereafter object in writing to the proposed formation of the Schaefer Ranch GHAD. The City Council of the City of Dublin will hold a public hearing on the proposed formation of the Schaefer Ranch GHAD on December 5, 2006.. If it appears at the hearing that the owners of more than 50 percent of the assessed valuation of property within the territory to be annexed object to the formation, the proceedings must be abandoned. At the close of the hearing, the City Council will decide whether or not to form the Schaefer Ranch GHAD. After the Schaefer Ranch GHAD is formed, the City Council must take additional steps to make the Schaefer Ranch GHAD operational. Specifically, the City Council must then appoint members to act as the initial Board of Directors for the Schaefer Ranch GHAD. The Board of Directors must then pass a budget and levy an assessment. Levying the assessment requires two steps: (a) approval of the engineer's report and the initiation of the assessment ballot proceeding, and (b) following the 45-day notice period required by Proposition 218, a public hearing to tabulate the assessment ballots and approve or deny the assessment. RECOMMENDATION: Staff recommends that the City Council adopt the Resolution Setting a Public Hearing on the Formation of the Schaefer Ranch Geologic Hazard Abatement District. Page 2 of2 16 ~;;L, RESOLUTION NO. . - 06 A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF DUBLIN ************************************* SETTING A PUBLIC HEARING ON THE FORMATION OF THE SCHAEFER RANCH GEOLOGIC HAZARD ABATEMENT DISTRICT WHEREAS, this Resolution is adopted pursuant to the provisions of Division 17 (Section 26500 et seq.) of the Public Resources Code, entitled "Geologic Hazard Abatement Districts"; and WHEREAS, on November 1,2006, the City Council of the City of Dublin was presented with a petition for the formation ofthe Schaefer Ranch Geologic Hazard Abatement District ("GHAD Petition"), including a plan of control ("Plan of Control"); and WHEREAS, the GHAD Petition, attached hereto as Exhibit A, is substantially in the form described in Section 26551 and 26552 of the Public Resources Code; and WHEREAS, the City Council reviewed the Plan of Control presented with the GHAD Petition and has determined that the health, safety and welfare require the formation of the Schaefer Ranch Geologic Hazard Abatement District ("District"); and WHEREAS, the City Council intends to schedule a public hearing ("Hearing") on the proposed formation of the District pursuant to the requirements of Section 26557 of the Public Resources Code. NOW, THEREFORE, BE IT RESOLVED THAT: Section 1. Findin2:s and Determinations The City Council hereby finds and determines that the above recitals are true and correct and have served as the basis, in part, for the findings and actions set forth below. Section 2. Public Hearin2: Scheduled The City Council will conduct a Hearing on the proposed formation of the District on December 5t\ 2006 at 7:00 p.m. or as soon thereafter as the matter can be heard, in the City Council Chambers, 100 Civic Plaza, Dublin, California, 94568. At the Hearing, any objections to the proposed district shall be presented. Section 3. Notice of Hearin2: A notice ofthe hearing ("Notice"), attached hereto as Exhibit B, shall be mailed to each owner of real property to be included in the proposed district as shown on the assessment roll last equalized by Alameda County. The Notice shall be mailed first-class, postage prepaid, in the United States mail and postmarked not less than 20 days preceding the date of the Hearing. The Notice shall include a copy of the GHAD Petition and shall indicate where the Plan of Control may /7-7-D& Lj, /0 Af-IztLh fYleh+ 1 /) FtJ~;) be reviewed or duplicated. The Notice shall also set forth the address where objections to the proposed formation may be mailed or otherwise delivered up to and including the time of the Hearing. Section 4. Obiections to Formation At any time not later than the time set for hearing objections to the proposed formation, any owner of real property within the proposed district may make a written obj ection to the formation. Such objection shall be in writing, shall contain a description ofthe land by lot, tract, and map number, and shall be signed by such owner. Objections shall be mailed or delivered as specified in the Notice. Ifthe person whose signature appears on such an objection is not shown on the assessment roll last equalized by Alameda County, the written objection shall be accompanied by evidence sufficient to indicate that such person is the owner of said property. PASSED AND ADOPTED on the 7th day of November, 2006, by the following vote: AYES: NOES: ABSENT: ABSTAINING: Mayor ATTEST: City Clerk 2 3fb'D d EXHIBIT A GHAD PETITION EXHIBIT A To the Resolution ~Ob~d PETITION FOR FORMATION OF THE SCHAEFER RANCH GEOLOGIC HAZARD ABATEMENT DISTRICT PURSUANT TO DIVISION 17 OF THE PUBLIC RESOURCES CODE OF THE STATE OF CALIFORNIA TO: The City Clerk for the City of Dublin: The undersigned owners of land within the boundaries of the territory proposed to be included in the Schaefer Ranch Geologic Hazard Abatement District ("District") hereby request that the City Council of the City of Dublin initiate proceedings for formation of the District to include the territory described in Exhibit A ("Boundary Map") and Exhibit B ("Legal Description"), attached hereto, pursuant to the provisions of Division 17 of the Public Resources Code sections 26500 et seq. Said owners are the owners of all the territory proposed for inclusion in the District. (a) This petition is made pursuant to Division 17 of the Public Resources Code with particular reference to Article 3 (commencing with Section 26550) and Article 4 (commencing with Section 26561 ). (b) Opposite the signature of each petitioner is an indication of the lot, tract and map number or other legal description sufficient to identify the signature of the petitioner as that of an owner of land within the territory proposed to be included in the District. (c) Opposite the signature of each petitioner is an indication of the date on which said petitioner's signature was affixed to this petition. 5iJb~;) (d) The following documents are attached to this petition and are incorporated herein by reference as if set forth in full in the petition: i. A map of the boundaries of the territory proposed to be included in the District (Exhibit A); ii. A legal description of the boundaries of the territory proposed to be included in the District (Exhibit B); and iii. A Plan of Control prepared by an engineering geologist certified pursuant to Section 7822 of the California Business and Professions Code, which describes in detail geologic hazards, their location and the areas affected thereby, and a plan for the prevention, mitigation, abatement and control thereof (Exhibit C). 0-/--0(0 Per Exhibits A & B Date Albert D. Seeno, III Signature of Petitioner Description of Property Date Signature of Petitioner Description of Property Date Signature of Petitioner Description of Property Date Signature of Petitioner Description of Property <6;:r EXHIBIT A BOUNDARY MAP EXHIBIT A . 70 i::he ?eti t/Ofl' MANUEL MACHADO EAST SA Y REGIONAL PARK OtSTRtCT ,~PN f}!3A..140(J.(j()1.o3 APN 85.IJ,.P400.()OU)5 ACCEPTED 1/4 CORNER ACCEPTED 1/4 CORNER COUNTY OF ALAMEDA us. 32 33 5 4 US S89'29.04"E 2594.61" S89'33.S2..E 1715. IS. CITY OF DUBLIN '" ~ :s '" ~ ).. .... ~ o <.:> \" ;;~ 6~ ~'" g;:? <:: ~ !1l Cl ~ ).. .... (:; ;...., :.0"" ~U ;::d l.:;, ~~~ '" ffit: (;)<( 444.83 t ACRES TOTAL EX/STING SCHAEFER RESIDENCE BEl-t!ES /'lO 99-13/918 600 EAST RA Y REG/ONAL PARK D/STR/CT '" ~ 11; :5 ~ '" Cl ~ ~ ).. i::: ~ (:; o US. (.) R.f.W 33 34 4 3"'- ACCEPTED 1/4 CORNER T.3S R.I.W TRACT 6765 SCHAEFER RANCH A PORTION OF SECTIONS 3 & 4, TOWNSHIP 3 SOUTH, RANGE 1 W!:ST, MT. DIABLO BASE AND MERIDIAN. CITY OF DUBLIN ALAMEDA COUNTY, CALIFORNIA ftJa DlUll!gn R8lICJWCeS, Ale. '7""" ~ . ........ . ....,.,.., APh! 85A-.,N!J()..U04..0i .700 y..- VaIIt,. RH4 _ 100 w_~____ SCALE: t" = toOO' 7EI.__OO NOVEMBER, 2006 EAST BA Y REGtONAL PARK D/STRlCT ~ :it ~ APN 94;.(;(j:8..008 L8 I o I 500 I 2000 I 1000 , \ \ \ /.'EAST RAY REGIONAL PARK D/Sm/CT ,...,.\./.... APsV 941-00U3.Q09 ..~ \ \ \ COUNTY OF ALAMEDA EXHIBIT 'A' GHAD BOUNDARY EXHIBIT SHEET 1 OF 2 .... --1 "I C)''" ~ Ii) LINE TABLE LINE LENGTH BEARING L1 145.11 $48 034 '1j "E L2 35.93 509'59'09"E 13 108.23 516'19"16"W L4 25.00 S13"40'44"E L5 438,12 541"19'00"E L6 249.89 532'04"20"< Ll 49144 SI8'05'49"E L8 502"81 502'20"33"E L9 176.93 518'35"08"E L10 178.88 500'34"01"W 111 338.98 519'09"21""W L12 221.56 584 '55"54"W L13 174.32 505'04"06"E L14 205.13 515'29"10"W L15 816.14 N89'42"48"E L16 51368 512'21"42""E L11 299 82 516'44 "06"E L18 565,51 N86"OI'31"E L19 118.45 590'OO"00"E L20 23881 N52'15"21"E L21 145.72 580'23"31"E L22 338.94 557'59"05"E L23 324"50 586'40"56""E L24 479.65 564 '23 "41"E L25 53"'8 531'11"05'E L26 54.55 552'46"22'W L21 64.98 562'26"35"E L28 5182 Nl7'29"03"W L29 41.26 524'46"42'W L30 36.60 ST9"18'2rw L31 45.12 N34"14'51"W L32 38653 584'49"OrW L33 122.22 521'31"J9"W L34 152.60 564'56"28"W L35 225.92 N54'OS'20"W L36 91.81 587'40"43"W L31 164.40 523'31"03"W LINE TABLE LINE LENGTH BEARING L38 195.64 514'01'35"W L39 204.10 N82'39"32'W L40 255.59 N53'44'04'W L41 105.06 S82"'8'S4"W L42 110.84 S19'51'38"W L43 T15.61 N89"27'Ol"W L44 154.13 N24'59"58"W L4S 216.11 S8S"SS"6"W L46 178.82 519'52"26"W L47 320.99 58S"17'16"W L48 UO.61 N2474'2S"W 149 294.12 S86'20"13"W L50 102.97 548'49"53"W L51 232"99 N66'31'21"W L52 241.96 N43'02"38"W L53 484.10 N14"41'36"W L54 318.64 581'08"09"W L55 426.98 N4f"39'34"W L56 260.44 N60"33'3rW L51 380"38 518'03"55"W L58 18.85 516'29"42"W L59 300.19 N14'30"24"W L60 458.31 N61'22"45"W L61 458.62 N75",,'25"W L62 401.40 N81'58"44'W L63 301.13 N16'12"50'W L64 222,75 N81"06'38"W L65 274.44 NSS"2f20"W L66 123"83 510'39"5S"W L6l 558.44 N03'08"04"E L68 890.26 588'22"02"< L69 583.44 N01'31"58"E LlO 539.69 N62"27"25"E Lll 341.12 562'21"25"W Ll2 319"35 NOO"30'45"W Ll3 2.43 553'16"1O"W Ll4 14.74 527'13 "56'W CIJRYE DA TA CIJRYE DELTA RADIUS LENGTH CI 59"21'40" 112.50' 119.02' C2 38'35"04" 231"50" 159"94" C3 26'18"25" 231.50" 109.05" C4 16'17"59'" 559.94' 159.29" C5 11'06"30'" 450.00' 81.24' C6 16"41'54" 1175.00' 342.44' Cl Ir24'SO" 1525.00" 330.42 C8 1'50"23"" 1115"00" 31.13" C9 6'25"39" 1225.00" 131.42" Cl0 26'02"14" 389"00" 176.18" CI1 0'20"22"" 8030"00' 41.56' C12 6'24'00' 1510"00" 175.31" C'3 4"29'19" 650.00" 50.92" TRACT 6765 SCHAEFER RANCH A PORTION OF SECTIONS 3 & 4, TOWNSHIP 3 SOUTH, RANGE t WEST, MT. DIABLO BASE AND MERIOIAN. CITY OF DUBLIN ft~LA:~';~ __ 'i,..... ,...... · .......... · ......... R100 Ypooo\> v-,. Rood, __ 1tItI w_ QowM, 00JN0n0I0 _ 7I!l IU6I _tJO NOVEMBER, 2006 EXHIBIT 'A' GHAD BOUNDARY EXHIBIT SHEET 2 OF 2 C<J ~ C>\\ ~) q at 6d- EXHIBIT B LEGAL DESCRIPTION EXHIBIT B. -I:: 0 -tlte '""kt:/tiol'l 1 t'b<6d- EXHIBIT "B" GHAD LEGAL DESCRIPTION ALL THAT REAL PROPERTY SITUATE IN THE COUNTY OF ALAMEDA, STATE OF CALIFORNIA, DESCRIBED AS FOLLOWS: A PORTION OF SECTIONS 3 AND 4, TOWNSHIP 3 SOUTH, RANGE 1 WEST, MOUNT DIABLO BASE AND MERIDAN, MORE PARTICULARLY DESCRIBED AS FOLLOWS: BEGINNING AT THE NORTHWEST CORNER OF SAID SECTION 4; THENCE ALONG THE NORTH SECTION LINE OF SAID SECTION 4, SOUTH 89029'04" EAST 2594,67 FEET TO THE NORTH ~ CORNER OF SAID SECTION 4; THENCE CONTINUING ALONG SAID NORTH SECTION LINE SOUTH 89033'52" EAST 1715,15 FEET; THENCE ALONG THE ARC OF A NON-TANGENT CURVE, THE RADIUS POINT OF WHICH BEARS SOUTH 79006'33" EAST, CONCAVE TO THE EAST, HAVING A RADIUS OF 172.50 FEET, THROUGH A CENTRAL ANGLE OF 59027'40", AN ARC LENGTH OF 179.02 FEET; THENCE SOUTH 48034'13" EAST 145.11 FEET; THENCE ALONG THE ARC OF A CURVE, CONCAVE TO THE SOUTHWEST, HAVING A RADIUS OF 237,50 FEET, THROUGH A CENTRAL ANGLE OF 38035'04", AN ARC LENGTH OF 159.94 FEET; THENCE SOUTH 09059'09" EAST 35.93 FEET; THENCE ALONG THE ARC OF A CURVE CONCAVE TO THE WEST, HAVING A RADIUS OF 237,50 FEET, THROUGH A CENTRAL ANGLE OF 26018'25", AN ARC LENGTH OF 109,05 FEET; THENCE SOUTH 16019'16" WEST 108.23 FEET; THENCE SOUTH 73040'44" EAST 25,00 FEET; THENCE SOUTH 41019'00" EAST 438,12 FEET; THENCE SOUTH 32004'20" EAST 249.89 FEET; THENCE SOUTH 18005'49" EAST 497.44 FEET; THENCE SOUTH 02020'33" EAST 502,81 FEET; THENCE SOUTH 18035'08" EAST 176.93 FEET; THENCE SOUTH 00034'07" WEST 178,88 FEET; THENCE SOUTH 19009'21" WEST 338.98 FEET; THENCE SOUTH 84055'54" WEST 227,56 FEET; THENCE SOUTH 05004'06" EAST 174.32 FEET; THENCE SOUTH 15029'10" WEST 205.73 FEET; THENCE NORTH 89042'48" EAST 816,74 FEET; THENCE SOUTH 72027'42" EAST 573,68 FEET; THENCE SOUTH 76044'06" EAST 299,82 FEET; THENCE NORTH 86001 '31" EAST 565,57 FEET; THENCE SOUTH 90000'00" EAST 118.45 FEET; THENCE NORTH 52015'21" EAST 238.87 FEET; THENCE SOUTH 80023'31" EAST 145,72 FEET; THENCE SOUTH 57059'05" EAST 338,94 FEET; THENCE SOUTH 86040'56" EAST 324.50 FEET; THENCE SOUTH 64023'41" EAST 479.65 FEET; THENCE ALONG THE ARC OF A NON-TANGENT CURVE, THE RADIUS POINT OF WHICH BEARS NORTH 69000'53" EAST, CONCAVE TO THE NORTHEAST, HAVING A RADIUS OF 559.94 FEET, THROUGH A CENTRAL ANGLE OF 16017'59", AN ARC LENGTH OF 159.29 FEET; THENCE SOUTH 37017'05" EAST 53,18 FEET; THENCE SOUTH 52046'22" WEST 54.55 FEET; THENCE SOUTH 62026'35" EAST 64,98 FEET; THENCE ALONG THE ARC OF A NON-TANGENT CURVE, THE RADIUS POINT OF WHICH BEARS NORTH <?;)... 01024'28" EAST, CONCAVE TO THE NORTH, HAVING A RADIUS OF 450.00 FEET, THROUGH A CENTRAL ANGLE OF 11006'30", AN ARC LENGTH OF 87,24 FEET; THENCE NORTH 77029'03" WEST 57,82 FEET; THENCE ALONG THE ARC OF A CURVE , CONCAVE TO THE SOUTH, HAVING A RADIUS OF 1175,00 FEET, THROUGH A CENTRAL ANGLE OF 16041'54", AN ARC LENGTH OF 342.44 FEET, TO A POINT OF NON-TANGENCY, THE RADIUS POINT OF WHICH BEARS SOUTH 04010'57" EAST; THENCE SOUTH 24046'42" WEST 41.26 FEET; THENCE SOUTH 79018'27" WEST 36,60 FEET; THENCE NORTH 34014'51" WEST 45.12 FEET; THENCE SOUTH 84049'07" WEST 386,53 FEET; THENCE ALONG THE ARC OF A CURVE, CONCAVE TO THE NORTH, HAVING A RADIUS OF 1525.00 FEET, THROUGH A CENTRAL ANGLE OF 12024'50", AN ARC LENGTH OF 330.42 FEET TO A POINT OF COMPOUND CURVATURE; THENCE ALONG SAID COMPOUND CURVE, CONCAVE TO THE NORTH, HAVING A RADIUS OF1175.00 FEET, THROUGH A CENTRAL ANGLE OF 01050'23, AN ARC LENGTH OF 37,73 FEET, TO A POINT OF NON-TANGENCY, THE RADIUS POINT OF WHICH BEARS SOUTH 05023'34" WEST; THENCE SOUTH 27037'39" WEST 122.22 FEET; THENCE SOUTH 64056'28" WEST 152,60 FEET; THENCE NORTH 54005'20" WEST 225.92 FEET; THENCE SOUTH 87040'43" WEST 91.81 FEET; THENCE ALONG THE ARC OF A NON- TANGENT CURVE, THE RADIUS POINT OF WHICH BEARS NORTH 09053'56" WEST, CONCAVE TO THE NORTH, HAVING A RADIUS OF 1225.00 FEET, THROUGH A CENTRAL ANGLE OF 06025'39", AN ARC LENGTH OF 137.42 FEET, TO A POINT OF NON-TANGENCY, THE RADIUS POINT OF WHICH BEARS NORTH 03028'17" WEST; THENCE SOUTH 23037'03" WEST 164.40 FEET; THENCE SOUTH 74001 '35" WEST 195.64 FEET; THENCE NORTH 82039'32" WEST 204.10 FEET; THENCE NORTH 53044'04" WEST 255.59 FEET; THENCE SOUTH 82018'54" WEST 105.06 FEET; THENCE SOUTH 19051 '38" WEST 170,84 FEET; THENCE NORTH 89027'07" WEST 115.61 FEET; THENCE NORTH 24059'58" WEST 154.13 FEET; THENCE SOUTH 88055'16" WEST 216.17 FEET; THENCE SOUTH 19052'26" WEST 178.82 FEET; THENCE SOUTH 85017'16" WEST 320.99 FEET; THENCE NORTH 24024'25" WEST 140,61 FEET; THENCE SOUTH 86020'13" WEST 294,72 FEET; THENCE SOUTH 48049'53" WEST 102,97 FEET; THENCE NORTH 66031'21" WEST 232.99 FEET; THENCE NORTH 43002'38" WEST 241.96 FEET; THENCE NORTH 74041 '36" WEST 484,10 FEET; THENCE SOUTH 81008'09" WEST 378,64 FEET; THENCE NORTH 41039'34" WEST 426,98 FEET; THENCE NORTH 60033'37" WEST 260.44 FEET; THENCE SOUTH 78003'55" WEST 380,38 FEET; THENCE SOUTH 53016'10" WEST 2.43 FEET; THENCE ALONG THE ARC OF A CURVE, CONCAVE TO THE SOUTHEAST, HAVING A RADIUS OF 389,00, THROUGH A CENTRAL ANGLE OF 26002'14", AN ARC LENGTH OF 176,78 FEET; THENCE SOUTH 27013'56" WEST 74,74 FEET; THENCE, ALONG THE ARC OF A NON-TANGENT CURVE, THE RADIUS POINT OF WHICH BEARS SOUTH 69001 '00" EAST, CONCAVE TO THE EAST, HAVING A RADIUS OF 650,00 FEET, THROUGH A CENTRAL ANGLE OF 04029'19", AN ARCH LENGTH OF 50.92 FEET; THENCE SOUTH 16029'42" WEST 18,85 FEET; THENCE NORTH 74030'24" WEST 300.19 FEET; THENCE NORTH 67022'45" WEST 458,31 FEET; THENCE NORTH 76011 '25" WEST 458,62 FEET; THENCE NORTH 87058'44" WEST 407.40 <t:~ ,J FEET; THENCE NORTH 76012'50"WEST 301.13 FEET; THENCE NORTH 81006'38" WEST 222,75 FEET; THENCE NORTH 55021 '20" WEST 274.44 FEET; THENCE SOUTH 70039'55"WEST 123,83 FEET; THENCE NORTH 03008'04" EAST 558.44 FEET; THENCE SOUTH 88022'02" EAST 890.26 FEET; THENCE NORTH 01037'58" EAST 583.44 FEET; THENCE NORTH 62027'25" EAST 539.69 FEET; THENCE ALONG THE ARC OF A NON-TANGENT CURVE, THE RADIUS POINT OF WHICH BEARS NORTH 24024'16" EAST, CONCAVE TO THE NORTHEAST, HAVING A RADIUS OF 8030.00 FEET, THROUGH A CENTRAL ANGLE OF 00020'22", AN ARC LENGTH OF 47,56 FEET TO A POINT ON A REVERSE CURVE; THENCE ALONG THE ARC OF A REVERSE CURVE, CONCAVE TO THE SOUTHWEST, HAVING A RADIUS OF 1570.00 FEET, THROUGH A CENTRAL ANGLE OF 06024'00", AN ARC LENGTH OF 175,37 FEET, TO A POINT OF NON-TANGENCY, THE RADIUS POINT OF WHICH BEARS SOUTH 18020'38" WEST; THENCE SOUTH 62027'25" WEST 341.72 FEET; THENCE NORTH 75052'39" WEST 963.67 FEET; THENCE NORTH 00030'45" WEST 319.35 FEET; THENCE NORTH 00050'31" EAST 1362.44 FEET TO THE POINT OF BEGINNING. CONTAINING 444.83 ACRES ( 19,376,631 SQ, FT,) MORE OR LESS. // ~Ol" (}h \~... "".' 1: if -:)1' ,.rJ V EXHIBIT C PLAN OF CONTROL . "PLAN OF CONTROL FOR SCHAEFER RANCH GEOLOGIC HAZARD ABATEMENT DISTRICT (GHAD) '. . nm1T~ to t:J..e Jli;;ir:iO pt PLAN OF CONTROL FOR SCHAEFER RANCH GEOLOGIC HAZARD ABATEMENT DISTRICT (GRAD) DUBLIN, CALIFORNIA SUBMITTED TO SCHAEFER RANCH, LLC PREPARED BY ENGEOINCORPORATED PROJECT NO. 4748.1.500.01 NOVEMBER 1, 2006 COPYRIGHT @ 2006 BY ENGEO INCORPORATED. THIS DOCUMEJ\'T MAY NOT BE REPRODUCED IN WHOLE OR IN PART BY ANY MEANS WHATSOEVER, NOR MAY IT BE QUOTED OR EXCERPTED WITHOUT THE EXPRESS WRITTEN CONSENT OF ENGEO INCORPORATED. . . . li.tJt~) ~~ ENC3EO INCORPORATED T ABLE OF CONTENTS Page I. Authority and Scope ,....""......,........."....".. ....."......... ..., ..... ...........,.. '..,..',..,.... ,..,. ...,'.., '.. 1 Property Identification".,.." ..,.......,....,.."....,....""..."..",.. .,.....".."",.....,..,....,.......".", ..,1 II. Background.... ......',.. .......".....,..'...." ...., ...........,..........,..,..,....."..........,......,.. ......... '......,.., 2 Pregrading Site Conditions........,' ....".."..,.."..".... ......",......,.."..,.....,..,.,..,..,............",..2 Proposed Development....."...".....,..",.."..,........"..,.,..,......,...., ,..,...........................,..... ,2 Open Space,........... ....... .....,.., .......,..,.... .........,..".." .....,'........................... ........"......,.., ,4 GHAD Responsibilities ....",.... .........,.."..."",.....,.......",....".....,......,....".........,......,.."..4 III. Site Geology.... ....,..,....,...." .....,., ....'..., ,..".. ......' , '....",..., ....,.. ...".."..,.,.. .............,....",.. ,....' 6 Geologic Setting""""""""."""""""",.."".""""",.""""".,."..""."",..""."""",.,.""""" 6 Site Geology.............,...........................,..."..".......".....,...",..........."..",...........,........,.... 6 IV. Geologic Hazards,..".." ....",.."..., ,.. ..." ......,......",,'...... ................"..,..,'....",....,....,'..." .....' 7 Slope Instability....,....,....,..,..",..,..,.." .......",..",.....".., .....".........,....,'..,..... ,.......,...." ...., 7 Erosion and Sedimentation ....,..,......,.... ...........' .....,.. ..... ..............", ...... ....".....,........., ..,9 Seismically-Induced Ground Shaking......"""...",...,.......,.....",...,..,.,...""".....,.,..".... ,..9 V. Criteria for GHAD Responsibility .............................,....,......,....................................., 11 Prevention, Mitigation, Abatement and/or Control of Geologic Hazards ....,..............11 Exceptions..,.."........"....,.,.." .........', ..'......,..........".....,..,..,..,..,..,.......",..,...,'..'",,'...., ...11 Isolated or Remote Slope Instability.. .............. ............. ........ ........... ......... ......,.. ,.. ..,.. ..11 Single Property..,.. .....,........ ..... ........."...."..,........,..", .......,...", ........., ...."".., .........,.... ..11 Geologic Hazards Resulting From Negligence of Property Owner,.......................,.... 12 Vertical Movement or Creep Due to Shrink Swell or Settlement ......................,....,...12 Protected Wildlife Habitat...,..",..".... ,....'......,.......,..',....."..,..,........,...."....,......, ...,..., ,13 Property Not Accepted,..,..,...., ...,...,.... .......'",.....' ....",..,..,......" ...............""..,... ......., ..13 Damage to GHAD Accepted Property from Landslide Originating on Property not Accepted by GHAD .. ....,..,.." ......"..,.......'..,......"..,......,........,.'....".........".....,...,..,..... ,13 GHAD Funding or Reimbursement for Damaged or Destroyed Structures or Site Improvements ,..",......"""..,....,..,..",..,.."..,....,..",..,..",.....,..".."..........",..."..,......".., ..13 VI. Acceptance"....,.."....,.........,..,..., ..........,...,.."..,......"................,...",.." ..... .... ..............'..'.. 15 Activation of Assessment..,.."" ....""'.....""""".."..,..""",......,,,.. .......'""..' ,..'"""".... ,15 Responsibility for GHAD Activities,................,.......,.."., ,....".,....,....."..,.... ........,...., ..15 VII. Schaefer Ranch GHAD Management Plan....,........,..,..............................,....,..,.............. 16 Landslide Mitigation for Existing Landslides and Erosion Features .......,...................17 Geotechnical Techniques for Mitigation of Landslide and Erosion Hazards ..............21 VIII. Priority of GHAD Expenditures................ ..,..............,.. ,...... ,.. ,.......... .........,....,.. ..,....... 23 IX. Biotechnical Recommendations for Prevention and Mitigation of Existing or Potential Erosion Hazards"....,...,..".. .....,..."..",....",.."..,..""........,....,..""..""".",.."....,....,.....""", 24 4748,1.500,01 November 1,2006 DRAFT C1 UO~~ EN<3EO INCORPORATED TABLE OF CONTENTS (Continued) X. Maintenance and Monitoring Schedule ..,..,..,........,.......,...............,...........,.................. 25 SELECTED REFERENCES EXHIBIT A - GHAD Legal Description EXHIBIT B - GHAD Boundary Exhibit GHAD Open Space Exhibit PLATE 1- Parcel Designation Plan PLATE 2 - Geologic Map APPENDIX A - Water Quality - Detention Basin Monitoring and Maintenance APPENDIX B- Site Geology 4748,1.500,01 November 1, 2006 DRAFT (1) db <D~ ENGEO INCORPORATED I. Authority and Scope The Schaefer Ranch Geologic Hazard Abatement District ("GHAD" or "District") is proposed to be formed under authority of the California Public Resources Code (Division 17, commencing with Section 26500), Formation of the GHAD has been proposed to provide a framework for the prevention, mitigation, abatement, and control of identified or potential geologic hazards, Development of a Plan of Control prepared by a State Certified Engineering Geologist is a requirement for formation of a GHAD, Pursuant to Section 26509, this Plan of Control was prepared by an engineering geologist certified pursuant to Section 7822 of the Business and Professions Code and describes the geologic hazards, their location, and the area affected by them, It also provides a plan for the prevention, mitigation, abatement, or control thereof, As used in this Plan of Control, and as provided in Section 26507, "geologic hazard" means an actual or threatened landslide, land subsidence, soil erosion, earthquake, fault movement, or any other natural or unnatural movement of land or earth, Property Identification The boundary of Schaefer Ranch (Tract 6765), the legal description of the property, its parcel designations, and the proposed boundary of the GHAD are shown in Exhibits A and B and Plate I. 4748,1.500.01 November 1,2006 DRAFT 1 1C1 ~ ~d- ENGEO INCORPORATED II. Background The Schaefer Ranch project is located on the north side of Highway 580 in west Dublin, California. The east side of the property borders open space for an adjacent subdivision and East Bay Regional Park District land, The northern side of the property borders East Bay Regional Park District land and the Machado Property. The west side of the property borders the DaVilla/Eden Canyon Family Partnership Property, Access to the site is currently provided via Schaefer Ranch Road through an existing freeway underpass, The site is approximately 445 acres in area and is bordered on the west and north by undeveloped land (the "GHAD Property"), The GHAD Property includes the area shown in Exhibit B, Pregrading Site Conditions The GHAD Property is located in an area dominated by a high ridgeline that reaches elevations of over 1,100 feet (Plate 2), In plan view, the crest of the ridge forms a "V" shape, open to the west. The high point on the property, Donlan Point at elevation 1,138 feet, occurs at the apex of the "V", at the east end of the high ridgeline, East of Donlan Point, a single ridgeline continues to the east at elevations of 750 to 900 feet. South of the ridge, the property slopes to Highway 580 at elevations of 600 to 700 feet. The center of the high ridge is drained by Marshall Canyon and Kelley Canyon, Wagon Wheel Canyon flows from a saddle south of the main ridge, All three canyons drain northwest, into undeveloped lands. The vegetation on site currently consists of open grassland in upland areas and south-facing slopes, local brush and tree cover in the canyon bottoms and some lower portions of north-facing slopes, Proposed Development The Preliminary Grading Plan for the subject property, developed by PIA Design Associates currently shows single family residential units, interior subdivision streets, a leisure park, a 4748,1,500,01 November 1, 2006 DRAFT 2 t';~ dO (J'D '6 cJ- ENGEO INCORPORA TED sports park, three detention basins, three water quality basins, a water tank, an East Bay Regional Park District trailhead, staging area and associated trails and an approximately 5.7 acre parcel at the site, A Geotechnical Investigation dated October 1997 was completed for the Schaefer Ranch site by Alan Kropp and Associates (AKA), ENGEO Incorporated performed a supplemental exploration at the Schaefer Ranch site and provided supplemental geotechnical recommendations in a report dated January 29, 2004, as well as subsequent documents listed in the references section, Grading plans for the subject site indicate that the majority of planned residential units will occupy cut areas along the west-northwest and northwest trending ridgelines at the site, Proposed residential units will also occupy building pads in fill areas in the southwest portion of the site west of proposed Schaefer Ranch Road and within the west and northwest portions of the site, In addition to the proposed residential development, a westward extension of Dublin Boulevard is planned at the site, Along the uphill side of the Dublin Boulevard Extension, 2: 1 (horizontal: vertical) slopes up to 180 feet in vertical height are planned, East of Station 30+50 the 2:1 slopes are planned to be rebuilt as engineered fill slopes, West of Station 30+50, portions of the 2:1 slopes outside of mapped landslide areas are not planned to be rebuilt. Landslides within the grading limits along Dublin Boulevard are planned to be completely removed and replaced with drained engineered fill, Benches with concrete-lined ditches and stormdrain systems are planned on graded slopes steeper than 3: 1, According to grading plans by P / A Design Resources, deep fill areas are planned at the southwest and northwest portions of the Schaefer Ranch Project site. Engineered fill within the above mentioned portions of the site are shown to extend up to approximately 150 feet above original grades in some places. ENGEO provided recommendations for the monitoring of deep fills in letters dated June 26, 2005, and August 17, 2005, Settlement instrumentation will be 4748,1.500.01 November 1, 2006 DRAFT 3 d lfiQ 1)OL- ENGEO INCORPORATED provided in the deep fill areas at the southwestern portion of the site west of Schaefer Ranch Road and in the deep fill area in the northwest portion of the site, The developer will provide for monitoring of the settlement instruments during grading as well as during the residential construction period, Open Space Project Open Space includes Parcels AI, Bl, C1, E, F, G, R, L, P, R, S, U and V as shown in Open Space Exhibit. Title to these parcels will be conveyed to the GRAD approximately three years after the recording of the first final map affecting the GHAD Property, Since long-term maintenance and stability of the GRAD Property will protect the open space, which is an amenity that will benefit all of the current and future property owners, the funding for the GRAD's activities will be shared by all current and future property owners within the GRAD's boundaries, All such activities shall be consistent with this Plan of Control. According to the GHAD Boundary Exhibit prepared by P A Design Resources (August 16, 2006) approximately 66 acres of open space designated as Parcel A has been deeded to the East Bay Regional Park District and will therefore be outside of the GRAD's boundaries, although the GRAD reserves the right to enter this property at its discretion in conjunction with maintenance and repairs on the GHAD property (see attached Exhibit B), GRAD Responsibilities The GHAD will mitigate, prevent, abate or repair landslide or erosion hazards that could directly affect property within the GRAD boundary, as necessary to implement this Plan of Control. The GRAD will also assume open-space management responsibilities that are required for the Schaefer Ranch Project. These responsibilities will include: vegetation management, erosion control, vegetation removal (fire suppression), and selected other maintenance associated with 4748,1.500,01 November 1, 2006 DRAFT 4 ;J ;J., ffb 1; ~ ENGEO INCORPORATED open space. In addition, the responsibility of the GRAD includes: maintenance, repair and replacement of detention basins (within the GRAD Property), vegetation control, armoring of channels and desilting of detention basins. The GRAD's responsibilities will include but may not be limited to monitoring and maintenance for the following as appropriate, . Detention Basins and Water Quality Basins on Parcels "R", "G" and "V", including structures, vegetation and sediment removal. · Maintenance and repair of EVA and access Roads, . Erosion repairs, · Revegetation and vegetation control, including fire break mowing, weeding and additional hydroseeding as deemed necessary, . Sediment removal from concrete structures (applies only to open-space catch basins, field inlets, V-ditches and stormdrain pipes), . Slope stabilization (includes minor landsliding and debris bench clearing), . Subdrain outfall maintenance. . Open-space stormdrain pipe and V-ditch replacement. In addition, the GRAD will have maintenance, monitoring and repair responsibilities for slopes, which will include natural, reconstructed or partially-reconstructed landslides as indicated within the referenced ENGEO reports and discussed below (Section V), 4748,1.500,01 November 1, 2006 DRAFT 5 d 3 d1 <6;). D ENGEO INCORPORATED III. Site Geology Geologic Setting The site is located within the Coast Ranges geologic provmce of California, a senes of northwest-trending ridges and valleys, Bedrock in the province has been folded and faulted during regional uplift beginning in the Pliocene period, roughly 4 million years before present. More specifically Schaefer Ranch is located in the central East Bay Hills, an area that is characterized by folded and faulted Cretaceous to Pliocene-age sedimentary rocks (Plate 2), The eastern and western geologic boundaries of the East Bay Hills are formed by the active Calaveras and Hayward Faults, Site Geology Regional geologic maps of the area have been prepared by Dibblee (1980), Crane (1988) and Graymer (1996). The most recent regional map prepared by Graymer indicates that the site is underlain by late and middle Miocene rocks of the Briones Formation and undivided middle Miocene marine rocks of the Monterey Group including the Rodeo Shale, Hambre Sandstone, Tice Shale and Ours an Sandstone, A more extensive discussion of the site geology is included as Appendix B of this Plan of Control. 4748,1.500,01 November 1, 2006 DRAFT 6 J <-t 1J <bd ENGEO INCORPORATED IV. Geologic Hazards Geologic hazards identified for the site in the AKA and ENGEO reports include the following items: . Lateral stability or slope stability . Erosion and sedimentation · Seismically-induced ground shaking Slope Instability Earth stability is the GRAD's prime geotechnical concern at this site, This is not unique to this project, but is of importance for hillside projects in the San Francisco Bay Area, This section describes several types of slope instability which are within the GRAD's responsibility, subject to the provisions of Section VI. Landslides are a common geologic phenomenon and are part of the process of mass wasting. Weathered or fractured bedrock and soil are transported downslope over geologic time as a result of gravitational and hydrostatic forces, Landslides and earth movement in this bedrock formation are typically rotational slumps and earthflows, Depth of movement is typically about 5 to 25 feet below the ground surface, In the winter rainy season, these earthflows can move at a rate of several feet per day, A landslide is a deposit of soil and/or bedrock moving downward from its original position under the influence of gravity, Landslides include a variety of morphologies and are further defined by type of materials, wetness, and mode of movement. They can consist of mass movements of earth materials that are primarily intact, and occur along discrete shear surfaces. These surfaces (shear or slip planes) can be rotational (conchoidal or concave), such as for earth slumps, or planar, as for translational earth slide or bedrock block glides, Most landslides are truly "complex landslides", sliding, falling and flowing with more than one type of movement and/or material. 4748,1.500,01 November 1, 2006 DRAFT 7 :J6Db <DoL ENGEO INCORPORATED According to the geotechnical reports for the project approximately 59 landslides have been identified on the subject site. The geologic map showing the location of each of the landslides is included as Plate 2, In general mitigation measures for the mapped landslides are to be performed in accordance with the approved remedial grading plans for the project. The proposed mitigation measures identified in the geotechnical report and the remedial grading plans include the following: complete removal of the landslide and replacement with drained engineered fill, removal and replacement of the lower portion of the landslide and replacement with a drained engineered fill buttress, and removal and replacement of the upper portion of the landslide within the grading limits and providing a keyway along the edge of the grading limits, According to the geotechnical report for the project, landslides that are completely outside of the proposed grading limits and pose no potential risk to the proposed development, will not be mitigated and will be left in-place, As-built remedial grading plans are to be prepared following grading at the site to show areas and locations where corrective grading was performed. Slope failures are also often triggered by increased pore water pressure due to the infiltration of rainwater. The resulting decrease of shear resistance (internal resistance to deformation by shearing) can cause the slope to move. The level of the groundwater table varies with the amount of rainfall for the area, If rainfall is higher than average during the winter season, the water table will be higher than average on a hillslope and groundwater pressures may become high, Under these conditions, hillside movement can be activated, Soil creep is the slow, often imperceptible, deformation of slope materials under low stress levels, which normally affects the shallow portion of the slopes, but can be deep seated where a weak zone of soil or bedrock exists, It results from gravitational and seepage forces, and may be indicative of conditions favorable for landsliding. Creep can be caused by wetting and drying of clays, by solution and crystallization of salts, by the growth of roots, by burrowing animals and by down slope movement of saturated ground, Colluvium refers to the thicker mantle of loose 4748,1.500,01 November 1, 2006 DRAFT 8 ;;d.~ 110 ~d- ENGEO INCORPORA TED soil and weathered bedrock debris that progresses down hillsides by creep, Colluvial deposits are typically the result of soil creep and may be in a weak, unconsolidated state, making them susceptible to landsliding if undercut. Colluvium is generally approximately 8 to 15 feet in thickness, Landslides and colluvial deposits located within open space areas are natural landforms that do not require mitigation except where they affect man-made improvements, Potential mitigation and repair measures for GRAD areas near development are discussed in Section VII. Erosion and Sedimentation The District shall also be concerned with erosion and sedimentation in open space or affecting established lots or improvements, Erosion is defined as the process by which earth materials are loosened and removed by running water on the ground surface or in the subsurface, Sedimentation is the depositing or settling of soil or rock particles from a state of suspension in a liquid, Hilly terrain in open space, either in a natural condition or particularly on excavated slopes, can be subject to erosion, Landslide deposits which are sometimes in a loosened condition are particularly prone to erosion, Earth flow, debris flow and mud flow landslides typically have an area of deposition or accumulation (sedimentation area) at their base, Graded slopes in the District, particularly those in excess of 20 feet in vertical height or those not sufficiently vegetated, can be subject to erosion and therefore, a source of transported sediment. Seismically-Induced Ground Shaking As identified in the geotechnical reports, an earthquake of moderate to high magnitude generated within the San Francisco Bay Region could cause considerable ground shaking at the site, similar to that which has occurred in the past. Seismic slope stability has been considered in the ENGEO 4748.1.500,01 November 1, 2006 DRAFT 9 dvl~ '6 L ENGEO INCORPORATED remedial grading plans for engineered fill slopes at the site, On unimproved open space slopes, seismically-generated slope failures may occur in open-space areas outside the development limits, 4748,1,500,01 November 1, 2006 DRAFT 10 ~'6D()gL EM3EO INCORPORATED v. Criteria for GHAD Responsibility Prevention, Mitigation, Abatement and/or Control of Geologic Hazards Subject to the following exceptions, the primary mission of the GHAD shall be the prevention, mitigation, abatement and/or control of geologic hazards within its boundaries that have damaged, or that pose a significant threat of damage to site improvements within the GHAD boundaries, As used herein, the term "site improvements" means buildings and outbuildings, roads, sidewalks, utilities and associated facilities/structures and geologic stabilization features, Exceptions The intent of this Plan of Control is not to extend the GHAD's responsibilities to every potential situation of slope instability, Specifically, the following are excluded from the GHAD's responsibilities: Isolated or Remote Slope Instability The GHAD shall not have responsibility to monitor, abate, mitigate or control isolated or remote slope instability that does not involve damage to or pose a significant threat to damage (a) site improvements or (b) off-site improvements if the threat of damage or damage is not caused by property or site improvements for which the GHAD is responsible. Single Property The GHAD will not prevent, mitigate, abate or control geologic hazards which are limited in area to a single parcel of property not owned by the GHAD unless the geologic hazard has damaged, or poses a significant threat of damage, to site improvements located on other property 4748.1.500.01 November 1,2006 DRAFT 11 dv q 1J <Do. ENGEO INCORPORATED within the GHAD boundaries, This exclusion does not apply to geologic hazards existing on common area property owned by the HOA or within the GHAD-owned Property, Geologic Hazards Resulting From Negligence of Property Owner The GHAD may, in the GHAD manager's sole discretion, decline to prevent, mitigate, abate or control geologic hazards which occurred or resulted from any negligence of the homeowner and/or the homeowner's contractors, agents or employees in developing, investigating, grading, constructing, maintaining or performing or not performing any post-development work on the subject property, Vertical Movement or Creep Due to Shrink Swell or Settlement Vertical movement due to shrink -swell of expansive soils or settlement of fills is expected at the site as with many residential developments in the area. Damage to site improvements resulting from shrink swell or settlement of fills is not the responsibility ofthe GHAD, 4748,1.500,01 November 1, 2006 DRAFT 12 '3 () ZfJ <6;;~ ENGEO INCORPORA TED Protected Wildlife Habitat The GHAD will not prevent, mitigate, abate or control isolated geologic hazards which are limited to mitigation areas and/or protected wildlife habitat unless the geologic hazard has damaged, or poses a significant threat of damage, to site improvements located on property within the GHAD boundaries, Property Not Accepted The GHAD shall not have responsibility to repair damaged site improvements which are situated on a parcel of real property that the GHAD has not accepted in accordance with Section VI, below. Damage to GHAD Accepted Property from Landslide Originating on Property not Accepted by GHAD The GHAD may monitor, abate, mitigate or control slope instability on a parcel of real property which (1) the GHAD has not accepted in accordance with Section VI, below, and (2) that is not excluded from GHAD responsibility by Paragraphs 1 and 2; provided that GHAD responsibility on such parcel shall be limited to the extent necessary to address damage or a significant threat to damage site improvements which are within a parcel of real property which the GHAD has accepted in accordance with Section VI, below, GHAD Funding or Reimbursement for Damaged or Destroyed Structures or Site Improvements In the event that improvements (including residences, landscape, hardscape, or any other structure) are damaged or destroyed due to, or as a result of, a geologic hazard, the GHAD may fund or reimburse the property owner for the expenses necessary to repair or replace the 4748,1.500,01 November 1, 2006 DRAFT 13 :3 I '1J ~d- ENC3EO INCORPORATED damaged or destroyed structure, site improvement or landscaping, Unless authorized by the Board of Directors, the dollar amount of the GRAD funding or reimbursement may not exceed an aggregate of ten percent (10%) of the costs incurred by the GRAD in preventing, mitigating, abating or controlling the geologic hazard responsible for the damage, 4748,1,500.01 November 1, 2006 DRAFT 14 7ZfJ ~.CY EM3EO INCORPORATED VI. Acceptance Activation of Assessment An annual assessment shall be fully authorized, prior to recordation of the Final Map in accordance with the Conditions of Approval, on all residential parcels in the GRAD and may be increased as provided by law to achieve the purposes of the GRAD and this Plan of Control. The assessment shall be levied by the GRAD on each individual residential parcel beginning the first fiscal year following issuance of a building permit for that parcel. Responsibility for GHAD Activities Except as provided for in Section V, the party that, on the date the Final Map within the boundaries of the GRAD is recorded in the Official Records of Alameda County, owns the developable parcels shown on the Final Map shall have the responsibility to perfonn all the activities of the GRAD on property within the final Map prior to transfer of such property to the GRAD. Pursuant to this Plan of Control, such responsibility shall automatically transfer to the GRAD at 9:00 a,m, on the day exactly three years after the completion and city approval of the grading for the Schaefer Ranch Project, or exactly three years, after the first occupancy permit for the Schaefer Ranch Project is issued by the City, whichever is later, and provided the improvements required by the Conditions of Approval for the Schaefer Ranch Project have been accepted, This transfer date may be extended at the sole discretion of the owners of the GRAD Property to be transferred, provided that the owners continue to perform the GHAD's activities and that the assessments continue to be levied during the extension period and that notice of such extension is delivered to the GRAD manager at least 30 days prior to the transfer date, The approximate three-year period between the levying of the GRAD assessment and the GRAD transfer will allow the GRAD to accumulate reserve funds without incurring significant expenses, 4748,1.500,01 November 1,2006 DRAfT 15 ~ ~ '1J <6 ()-" EM3EO INCORPORATED VII. Schaefer Ranch GHAD Management Plan The GRAD will subject to the criteria outlined in Section V, monitor, mitigate and repair landslide or erosion hazards within the GRAD boundaries, Subject to the same criteria, the OHAD will also monitor, maintain, and repair the following within the GRAD boundary. . Detention Basins and Water Quality Basins on Parcels "R", "0" and "V", including structures, vegetation and sediment removal . Maintenance and repair of EVA and access Roads, . Erosion repairs. . Revegetation and vegetation control, including fire break mowing, weeding and additional hydro seeding as deemed necessary, . Sediment removal from concrete structures (applies only to open-space catch basins, field inlets, V-ditches and stormdrain pipes), . Slope stabilization (includes minor landsliding and debris bench clearing), . Subdrain outfall maintenance, . Open-space stormdrain pipe and V-ditch replacement. . Any other duties that the OHAD manager deems necessary for the management of areas within the GRAD boundaries, The GRAD will be authorized to maintain the geologic stabilization features (e.g. ditches, benches, walls, etc.) in the open space, and the unimproved areas including the hillside slopes extending uphill from debris benches and common areas outside of the private lot boundaries except where noted in section X. The GRAD's maintenance responsibilities include prevention, abatement, and control of landslide and erosion hazards within the subdivision open space and hillsides, as provided in Section V. 4748,1.500.01 November 1, 2006 DRAFT 16 2>t..f ~ 6 Cr ENGEO INCORPORATED General maintenance of the surface drainage improvements in the open space and on the hillsides, such as the concrete V-ditches, will be the GRAD's responsibility, The GRAD is also responsible for general maintenance of the stormdrain inlets and outlets in open space as well as the sub drain outlets, Potential geologic hazards such as landslides and slope erosion within the open space, including the unimproved hillsides, shall be the responsibility of the GRAD in accordance with Section V of this report, Clearing of fire breaks and general maintenance of the open space (other than hazard abatement) will be performed by the GRAD, Landslide Mitigation for Existing Landslides and Erosion Features For existing landslide areas the following mitigation measures have been proposed within the geotechnical investigation reports. General landslide mitigation measures and potential GHAD maintenance and monitoring activities are shown below. Landslide Proposed Corrective Potential GRAD Maintenance or Monitoring . Designations Measures B-1 Complete removal Routine observation during periodic site monitoring events. Remove and replace lower Upslope portions of Bedrock Landslide above the repair portion of landslide to remain, Observation of this area during periodic site B-2 underlying improvements, monitoring events, Higher potential for corrective work in Provide intervening future if landslide debris movement impacts rebuilt portion deposition area of slope or site improvements. See Section vn for potential landslide mitigation techniques. None Required Landslide to remain in place, Routine observation during B-3 Outside of grading limits and within open space area periodic site monitoring events, B-4 Complete removal Routine observation during periodic site monitoring events, B-5 Complete removal Routine observation during periodic site monitoring events, B-6 Complete removal Routine observation during periodic site monitoring events, None Required Landslide to remain in place, Routine observation during B-7 Outside of grading limits and within open space area periodic site monitoring events, L-l Complete removal Routine observation during periodic site monitoring events, L-2 Complete removal Routine observation during periodic site monitoring events. Removal of the upper portion Lower portion of landslide within open space area and L-3 of the landslide within grading outside of grading limits to remain, Routine observation limits during periodic site monitoring events, 4748.1.500.01 November 1, 2006 DRAFT 17 36"li6 (;6 ENGEO INCORPORATED Landslide Proposed Corrective Potential GHAD Maintenance or Monitoring Activities Designations Measures None Required Landslide to remain in place, Routine observation during L-4 Outside of grading limits and within open space area periodic site monitoring events. None Required Landslide to remain in place. Routine observation during L-5 Outside of grading limits and within open space area periodic site monitoring events, None Required Landslide to remain in place, Routine observation during L-6 Outside of grading limits and within open space area periodic site monitoring events. None Required Landslide to remain in place, Routine observation during L-7 Outside of grading limits and within open space area periodic site monitoring events, Shallow upslope margins of landslide above the repair to remam. Observation of this area during periodic site Removal of the lower portion monitoring events. Higher potential for maintenance or L-8 of the landslide within cut corrective work in future iflandslide debris is shed on to slope rebuild area. benches of rebuilt slope or shallow movement impacts rebuilt portion of slope or site improvements, See Section vn for potential landslide mitigation techniques. Remove and replace lower Shallow upslope margins of landslide above the repair to portion of landslide remain, Observation of this area during periodic site L-9 underlying improvements, monitoring events. Higher potential for maintenance or corrective work in future iflandslide debris is shed into Provide intervening intervening debris deposition area. See Section VII for deposition area potential landslide mitigation techniques. L-10 Complete removal Routine observation during periodic site monitoring events. L-11 Complete removal Routine observation during periodic site monitoring events. Remove and replace more Shallow upslope portion of landslide above the repair to significant lower portion of remain. Observation of this area during periodic site L-12 landslide underlying monitoring events. Higher potential for maintenance or improvements, Provide corrective work in future if landslide debris is shed into intervening debris deposition area, See Section VII for intervening deposition area potential landslide mitigation techniques. Remove and replace lower Upslope portion of landslide above the repair to remain. portion of landslide Observation of this area during periodic site monitoring L-13 underlying improvements, events. Higher potential for maintenance or corrective work Provide intervening in future if landslide debris is shed into intervening debris deposition area deposition area, See Section vn for potential landslide mitigation techniques. Remove and replace lower Upslope portion of landslide above the repair to remain. L-14 portion of landslide Observation of this area during periodic site monitoring underlying improvements, events, Higher potential for maintenance or corrective work 4748,1.500,01 November 1, 2006 DRAFT 18 :3.~ tJD <6.~. ENGEO INCORPORA TED Landslide Proposed Corrective Potential GHAD Maintenance or Monitoring Activities Deshmations Measures Provide intervening in future iflandslide debris is shed into intervening debris deposition area deposition area, See Section VlI for potential landslide mitigation techniques. Shallow upslope margins of landslide above the repair to Removal of the more remain, Observation of this area during periodic site significant lower portion of the monitoring events, Higher potential for maintenance or L-15 corrective work in future iflandslide debris is shed on to landslide within cut slope benches of rebuilt slope or shallow movement impacts rebuild area. rebuilt portion of slope or site improvements, See Section VlI for potential landslide mitigation techniques. Shallow upslope margins of landslide above the repair to Removal of the more remain, Observation of this area during periodic site significant lower portion of the monitoring events, Higher potential for maintenance or L-16 corrective work in future if landslide debris is shed on to landslide within cut slope benches of rebuilt slope or shallow movement impacts rebuild area, rebuilt portion of slope or site improvements, See Section vn for potential landslide mitigation techniques, Shallow upslope margins of landslide above the repair to Removal of the more remain. Observation of this area during periodic site significant lower portion of the monitoring events. Higher potential for maintenance or L-17 corrective work in future iflandslide debris is shed on to landslide within cut slope benches of rebuilt slope or shallow movement impacts rebuild area, rebuilt portion of slope or site improvements, See Section VlI for potential landslide mitigation techniques, None Required Landslide to remain in place. Routine observation during L-18 Outside of grading limits and within open space area periodic site monitoring events. Removal of the upper portion Lower portion of landslide within open space area and L-19 of the landslide within grading outside of grading limits to remain, Routine observation limits during periodic site monitoring events, None Required Landslide to remain in place, Routine observation during L-20 Outside of grading limits and within open space area periodic site monitoring events, L-2l Complete removal Routine observation during periodic site monitoring events, L-22 Complete removal Routine observation during periodic site monitoring events. L-23 Complete removal Routine observation during periodic site monitoring events. L-24 Complete removal Routine observation during periodic site monitoring events. L-25 Complete removal Routine observation during periodic site monitoring events, L-26 Complete removal Routine observation during periodic site monitoring events, L-27 Complete removal Routine observation during periodic site monitoring events. L-28 Complete removal Routine observation during periodic site monitoring events. L-29 Complete removal Routine observation during periodic site monitoring events, 4748.1.500,01 November 1, 2006 DRAFT 19 ~&; INCORPORATED Landslide Proposed Corrective Potential GHAD Maintenance or Monitoring Activities Designations Measures L-30 Complete removal Routine observation during periodic site monitoring events. Upslope portion oflandslide above the repair to remain. Remove and Replace Observation of this area during periodic site monitoring Portions Underlying events, Higher potential for maintenance or corrective work L-3l Improvements, Construct in future if landslide debris is shed on to benches of rebuilt Buttress and Debris slope or shallow movement impacts rebuilt portion of slope Catchment Bench or site improvements, See Section VII for potential landslide mitigation techniques. L-32 Complete removal Routine observation during periodic site monitoring events. None Required Landslide to remain in place, Routine observation during L-33 Outside of grading limits and within open space area periodic site monitoring events. None Required Landslide to remain in place, Routine observation during L-34 Outside of grading limits and within open space area periodic site monitoring events, None Required Landslide to remain in place, Routine observation during L-35 Outside of grading limits and within open space area periodic site monitoring events. None Required Landslide to remain in place. Routine observation during L-36 Outside of grading limits and within open space area periodic site monitoring events, None Required Landslide to remain in place, Routine observation during L-37 Outside of grading limits and within open space area periodic site monitoring events. Lower portion of landslide within open space area and Remove and Replace outside of grading limits to remain, Observation of this Portions Underlying area during periodic site monitoring events, Higher potential L-38 Improvements, Construct for corrective work in future if downslope movement of Buttress Key at Upper landslide leads to regression of heads carp into areas of site Landslide Limits, improvements. See Section vn for potential landslide mitigation techniques. None Required Landslide to remain in place. Routine observation during L-39 Outside of grading limits and within open space area periodic site monitoring events. None Required Landslide to remain in place, Routine observation during L-40 Outside of grading limits and within open space area periodic site monitoring events, None Required Landslide to remain in place, Routine observation during L-41 Outside of grading limits and within open space area periodic site monitoring events, L-42 None Required Routine observation during periodic site monitoring events. Outside of grading limits 4748,1,500,01 November 1, 2006 DRAFT 20 r'. .. 0 ? '6116 D;) EN<3EO L-43 L-44 L-45 L-46 L-47 L-48 L-49 L-50 L-5l L-52 Proposed Corrective Measures and within 0 en s ace area None Required Outside of grading limits and within 0 en s ace area None Required Outside of grading limits and within 0 en s ace area None Required Outside of grading limits and within 0 en s ace area None Required Outside of grading limits and within 0 en s ace area None Required Outside of grading limits and within 0 en s ace area None Required Outside of grading limits and within 0 en s ace area None Required Outside of grading limits and within 0 en s ace area None Required Outside of grading limits and within 0 en s ace area None Required Outside of grading limits and within 0 en s ace area None Required Outside of grading limits and within open space area INCORPORATED Potential GHAD Maintenance or Monitorin Landslide to remain in place, Routine observation during periodic site monitoring events, Landslide to remain in place, Routine observation during periodic site monitoring events. Landslide to remain in place. Routine observation during periodic site monitoring events, Landslide to remain in place, Routine observation during periodic site monitoring events, Landslide to remain in place. Routine observation during periodic site monitoring events, Landslide to remain in place, Routine observation during periodic site monitoring events. Landslide to remain in place, Routine observation during periodic site monitoring events, Landslide to remain in place. Routine observation during periodic site monitoring events, Landslide to remain in place, Routine observation during periodic site monitoring events. Landslide to remain in place, Routine observation during periodic site monitoring events. Geotechnical Techniques for Mitigation of Landslide and Erosion Hazards The techniques which may be employed by the GHAD to prevent, mitigate, abate, or control geologic hazards include, but are not necessarily limited to: A. Removal of the unstable earth mass, 4748,1.500.01 November 1,2006 DRAFT 21 3qtr.~ ~~ ENG~O INCORPORA TED B, Stabilization (either partial or total) of the landslide by removal and replacement with compacted, drained fill, C. Construction of structures to retain or divert landslide material or sediment. D, Construction of erosion control devices such as gabions, riprap, geotextiles, or lined ditches, E, Placement of drained engineered buttress fill. F, Placement of subsurface drainage devices; (e,g, underdrains, or horizontal drilled drains), G, Slope correction (e,g, gradient change, biotechnical stabilization, slope trimming or contouring), H, Construction of additional surface ditches and/or detention basins, silt fences, sediment traps, or backfill or erosion channels, Potential landslide and erosion hazards can be mitigated best by controlling soil saturation and water runoff and by maintaining the surface and subsurface drainage system, Maintenance shall be provided for lined surface drainage ditches and drainage terraces including debris benches or drop inlets. 4748,1.500,01 November 1, 2006 DRAFT 22 ~ 0 ~ ~d ENGEO INCORPORATED VIII. Priority of GHAD Expenditures Emergency response and scheduled repair expenditures by the GRAD are to be assigned a priority at the discretion of the GRAD manager based upon available funds and the approved operating budget. GRAD expenditures shall be prioritized as follows in descending order of priority: A. Prevention, mitigation, abatement or control of geologic hazards that have either damaged or pose a significant threat of damage to residences, critical underground utilities or paved streets. B. Prevention, mitigation, abatement or control of geologic hazards which have either damaged or pose a significant threat of damage to ancillary structures, including but not limited to the detention basins, or community buildings. C, Prevention, mitigation, abatement or control of geologic hazards which have either damaged or pose a significant threat of damage to open space amenities including vegetation that part of the irrigated, maintained, ornamental landscaping, D, Prevention, mitigation, abatement or control of geologic hazards existing entirely on open-space property and which have neither damaged nor pose a significant threat of damage to any site improvements, 4748,1,500,01 November 1,2006 DRAFT 23 Jk~Jd- INCORPORATED IX. Biotechnical Recommendations for Prevention and Mitigation of Existing or Potential Erosion Hazards Maintenance of vegetative cover is important on all slopes cut or fill, Vegetation provides a protective role on soil and exposed rock. It absorbs the impact of raindrops, reduces the velocity of runoff, and retards erosion, The GRAD may plant carefully selected and placed biological elements (plants), In addition, if the GRAD manager determines that it is necessary, biotechnical slope protection may also involve the use of mechanical elements or structures in combination with biological elements to provide erosion control and help prevent small-scale slope failures, Locally, crib walls, welded- wire walls, gabion walls, rock walls, riprap, and reinforced earth walls used in combination with carefully selected and planted vegetation can provide high quality slope protection, The vegetation may be planted on the slope above a low retaining structure or toe wall, or the interstices of the structure can be planted, 4748.1.500,01 November 1, 2006 DRAFT 24 42.11) ~'2~ ENGEO INCORPORATED x. Maintenance and Monitoring Schedule Geologic features and GHAD maintained facilities should be inspected by GHAD staff or GHAD-assigned consultants as presented below, The annual budget should be calculated so that inspections will be scheduled to occur two times per year and as necessary after heavy rainfall events that is defined as greater than 1 inch of rainfall in a 12-hour period, The inspections should be scheduled to take place in October, prior to the first significant rainfall; mid-winter as necessary during heavy rainfall years or events; and in early April, at the end of the rainy season, The frequency of the inspections should be increased in years of higher than average rainfall intensity and recurrence, The timing, frequency and other details regarding such maintenance, inspection and similar activities will be set forth in the Management Plan prepared by the GHAD manager. It is our understanding that in some instances slopes, benches and drainage structures which are to be maintained by the GHAD shall extend across private parcels, Access for maintenance and repair of these features shall be granted to the GHAD through easements established in favor of the GHAD. The GHAD shall obtain copies of geologic or geotechnical exploration reports related to site development and keep these reports on file in the records of the GHAD, In addition, copies of any earthwork-related testing and observation reports that will be finalized at the completion of grading, when as-built drawings are available, shall be maintained as part of the GHAD records, Following are guidelines for a monitoring plan, The actual scope and frequency of monitoring events shall be at the discretion of the GHAD manager. . The General Manager's engineer and/or geologist should inspect the lined surface ditches on a regular schedule, If possible, inspections should be scheduled twice each year, budget permitting, One inspection should be in the fall prior to the onset of winter rains, The 4748,1.500,01 November 1, 2006 DRAFT 25 y,~. DV 32- ENGEO INCORPORATED inspector should check for sedimentation, cracking or shifting of the concrete-lined ditches. Repairs and maintenance should be performed on a regular schedule, Excess silt or sediment in ditches should be removed and cracked or broken ditches should be patched or repaired as required prior to the beginning of the next rainy season, . Subsurface drain outlets and horizontal drilled drain outlets, if any, should be inspected on a regular basis. Water flowing from these outlets should be measured and recorded during each inspection, If possible, inspections should be scheduled twice each year, preferably in the fall and spring, Any suspicious interruption in flow should signal a need to unplug or clean the affected drain. . Inlets, outfalls or trash racks, if used, must be kept free of debris and spillways maintained, Attention should be given to plantings or other obstructions which may interfere with access by power equipment. The detention basins and water quality ponds on Parcels "R", "G" and "V" should be monitored 4 times each year, as appropriate, The monitoring schedule should occur in January, April, October, and as necessary during heavy rainfall events, A more detailed schedule of monitoring items and sample monitoring report forms are included in the detention basin monitoring and maintenance section presented in Appendix A, An annual inspection shall be made by the engineer and/or engineering geologist to assess the effectiveness of the preventive maintenance program and to make recommendations as to which landslide or erosion measures should be undertaken in the next fiscal year. Any appropriate site-specific study of landslide or erosion conditions shall be determined at that time, Consultants, if necessary, will be retained to undertake the needed studies, An annual inspection report shall be prepared by the GRAD Engineer and/or engineering geologist for the GRAD, Distribution of the annual report along with the budget information shall include City of Dublin Public Works Director, 4748,1.500,01 November 1, 2006 DRAFT 26 vt Yri[) ~2- EIVGEO INCORPORA TED SELECTED REFERENCES Alan Kropp & Associates, 1997, Geotechnical Investigation, Schaefer Ranch Subdivision, Dublin, California, Dated October, 1997, Project Number 1051-1 C, California Department of Conservation, 1996, California Fault Parameter, Division of Mines and Geology, Open File Report 96-08, Crane, R., 1995, Geology of the Mount Diablo Region, in Geology of the Mount Diablo Region Guidebook, Northern California Geological Society, Dibblee, T,W., 1980, Preliminary geologic map of the Dublin quadrangle, Alameda and Contra Costa Counties, California: D,S, Geological Survey, Open-File Report OF-80-537, scale 1 :24000, ENGEO Inc" 2004, Supplemental Geotechnical Recommendations, Schaefer Ranch Project, Dublin, California, dated January 29,2004, Project No.4748,1.001.01 ENGEO Inc" 2005, Geotechnical Recommendations for Existing Mitigation Pond PP10 at Marshall Canyon, Schaefer Ranch Project, Dublin, California, dated April 14, 2005, Project No.4748, 1.001.01 ENGEO Inc" 2005, Geotechnical Review of Mitigation and Watershed Enhancement Planting and Grading Plans and Supplemental Geotechnical Criteria, Schaefer Ranch Project, Dublin, California, dated June 9,2005, Project No.4748,1.001.01 ENGEO Inc., 2005, Recommendations for Settlement Monitoring of Planned Deep Fill Areas, Schaefer Ranch Project, Dublin, California, dated June 26, 2005, Project No.4748.1,OOl,Ol ENGEO Inc" 2005, Recommendations for Settlement Monitoring of Planned Deep Fill Areas, Schaefer Ranch Project, Dublin, California, dated August 17, 2005, Project No.4748.1,OOl,Ol Graymer, R, W., Jones, D, L. and Brabb, E, E" 1994, Preliminary Geologic Map Emphasizing Bedrock Formations in Alameda County, California: OFR 96-252, Federal Emergency Management Agency, 1982, National Flood Insurance Program, Flood Insurance Rate Map (FIRM), Panel Number 065048 0025 B, 4748,1.500,01 November 1, 2006 DRAFT L/0 irfJq;~ ENGEO INCORPORATED SELECTED REFERENCES (Continued) Unruh, J, R, and Sawyer, T, L., 1997, Assessment of Blind Seismogenic Sources, Livermore Valley, Eastern San Francisco Bay Region: Final Technical Report by William Lettis Associates and Piedmont Geosciences Inc, for the U, S, Geologic Survey National Earthquake Hazards Reduction Program, Unruh, 2000, Characterization of Blind Seismogenic Sources in the Mt. Diablo-Livermore Region, San Francisco Bay Area, California: Final Technical Report by William Lettis & Associates for the U, S, Geologic Survey National Earthquake Hazards Reduction Program, Wagner, J. R., 1978, Late Cenozoic History of the Coast Ranges East of San Francisco Bay, Ph,D, Dissertation, University of California, Berkeley, Working Group on California Earthquake Probabilities, 1999, Earthquake Probabilities in the San Francisco Bay Region: 2000 to 2030 - A Summary of Findings: USGS Open-File Report 99-517, 4748,1.500,01 November 1, 2006 DRAFT ~fa ffb 97- ENGEO INCORPORATED EXHIBIT A P / A Design Resources Legal Description 4748,1.500.01 November 1, 2006 DRAFT eft rriJq .~ EXHIBIT " A" GRAD LEGAL DESCRIPTION ALL THAT REAL PROPERTY SITUATE IN THE COUNTY OF ALAMEDA, STATE OF CALIFORNIA, DESCRIBED AS FOLLOWS: A PORTION OF SECTIONS 3 AND 4, TOWNSHIP 3 SOUTH, RANGE 1 WEST, MOUNT DIABLO BASE AND MERIDAN, MORE PARTICULARLY DESCRIBED AS FOLLOWS: BEGINNING AT THE NORTHWEST CORNER OF SAID SECTION 4; THENCE ALONG THE NORTH SECTION LINE OF SAID SECTION 4, SOUTH 89029'04" EAST 2594.67 FEET TO THE NORTH ~ CORNER OF SAID SECTION 4; THENCE CONTINUING ALONG SAID NORTH SECTION LINE SOUTH 89033'52" EAST 1715.15 FEET; THENCE ALONG THE ARC OF A NON-TANGENT CURVE, THE RADIUS POINT OF WHICH BEARS SOUTH 79006'33" EAST, CONCAVE TO THE EAST, HAVING A RADIUS OF 172.50 FEET, THROUGH A CENTRAL ANGLE OF 59027'40", AN ARC LENGTH OF 179.02 FEET; THENCE SOUTH 48034'13" EAST 145.11 FEET; THENCE ALONG THE ARC OF A CURVE, CONCAVE TO THE SOUTHWEST, HAVING A RADIUS OF 237.50 FEET, THROUGH A CENTRAL ANGLE OF 38035'04", AN ARC LENGTH OF 159.94 FEET; THENCE soum 09059'09" EAST 35.93 FEET; THENCE ALONG THE ARC OF A CURVE CONCAVE TO THE WEST, HAVING A RADIUS OF 237.50 FEET, THROUGH A CENTRAL ANGLE OF 26018'25", AN ARC LENGTH OF 109.05 FEET; THENCE SOUTH 16019'16" WEST 108,23 FEET; THENCE SOUTH 73040'44" EAST 25.00 FEET; THENCE SOUTH 41019'00" EAST 438,12 FEET; THENCE SOUTH 32004'20" EAST 249.89 FEET; THENCE SOUTH 18005'49" EAST 497,44 FEET; THENCE SOUTH 02020'33" EAST 502,81 FEET; THENCE SOUTH 18035'08" EAST 176,93 FEET; THENCE SOUTH 00034'07" WEST 178.88 FEET; THENCE SOUTH 19009'21" WEST 338.98 FEET; THENCE SOUTH 84055'54" WEST 227.56 FEET; THENCE SOUTH 05004'06" EAST 174.32 FEET; THENCE SOUTH 15029'10" WEST 205.73 FEET; THENCE NORTH 89042'48" EAST 816.74 FEET; THENCE SOUTH 72027'42" EAST 573.68 FEET; THENCE SOUTH 76044'06" EAST 299.82 FEET; THENCE NORTH 86001'31" EAST 565.57 FEET; THENCE SOUTH 90000'00" EAST 118.45 FEET; THENCE NORTH 52015'21" EAST 238.87 FEET; THENCE SOUTH 80023'31" EAST 145.72 FEET; THENCE SOUTH 57059'05" EAST 338,94 FEET; THENCE SOUTH 86040'56" EAST 324.50 FEET; THENCE SOUTH 64023'41" EAST 479.65 FEET; THENCE ALONG THE ARC OF A NON-TANGENT CURVE, THE RADIUS POINT OF WHICH BEARS NORTH 69000'53" EAST, CONCAVE TO THE NORTHEAST, HAVING A RADIUS OF 559.94 FEET, THROUGH A CENTRAL ANGLE OF 16017'59", AN ARC LENGTH OF 159,29 FEET; THENCE SOUTH 37017'05" EAST 53.18 FEET; THENCE SOUTH 52046'22" WEST 54,55 FEET; THENCE SOUTH 62026'35" EAST 64.98 FEET; THENCE ALONG THE ARC OF A NON-TANGENT CURVE, THE RADIUS POINT OF WHICH BEARS NORTH . 'Zjb ~-d- 01024'28" EAST, CONCAVE TO THE NORTH, HAVING A RADIUS OF 450,00 FEET, THROUGH A CENTRAL ANGLE OF 11006'30", AN ARC LENGTH OF 87,24 FEET; THENCE NORTH 77029'03" WEST 57.82 FEET; THENCE ALONG THE ARC OF A CURVE , CONCA VE TO THE SOUTH, HAVING A RADIUS OF 1175,00 FEET, THROUGH A CENTRAL ANGLE OF 16041 '54", AN ARC LENGTH OF 342.44 FEET, TO A POINT OF NON-TANGENCY, THE RADIUS POINT OF WIDCH BEARS SOUTH 04010'57" EAST; THENCE SOUTH 24046'42" WEST 41.26 FEET; THENCE SOUTH 79018'27" WEST 36.60 FEET; THENCE NORTH 34014'51" WEST 45.12 FEET; THENCE SOUTH 84049'07" WEST 386.53 FEET; THENCE ALONG THE ARC OF A CURVE, CONCAVE TO THE NORTH, HAVING A RADIUS OF 1525,00 FEET, THROUGH A CENTRAL ANGLE OF 12024'50", AN ARC LENGTH OF 330.42 FEET TO A POINT OF COMPOUND CURVATURE; THENCE ALONG SAID COMPOUND CURVE, CONCAVE TO THE NORTH, HAVING A RADIUS OF1l75.00 FEET, THROUGH A CENTRAL ANGLE OF 01050'23, AN ARC LENGTH OF 37.73 FEET, TO A POINT OF NON-TANGENCY, THE RADIUS POINT OF WHICH BEARS SOUTH 05023'34" WEST; THENCE SOUTH 27037'39" WEST 122.22 FEET; THENCE SOUTH 64056'28" WEST 152.60 FEET; THENCE NORTH 54005'20" WEST 225.92 FEET; THENCE SOUTH 87040'43" WEST 91.81 FEET; THENCE ALONG THE ARC OF A NON-TANGENT CURVE, THE RADIUS POINT OF WHICH BEARS NORTH09()53'56" WEST, CONCAVE TO THE NORTH, HAVING A RADIUS OF 1225.00 FEET, THROUGH A CENTRAL ANGLE OF 06025'39", AN ARC LENGTH OF 137.42 FEET, TO A POINT OF NON-TANGENCY, THE RADIUS POINT OF WHICH BEARS NORTH 03028'17" WEST; THENCE SOUTH 23037'03" WEST 164.40 FEET; THENCE SOUTH 74001 '35" WEST 195.64 FEET; THENCE NORTH 82039'32" WEST 204.1 0 FEET; THENCE NORTH 53044'04" WEST 255.59 FEET; THENCE SOUTH 82018'54" WEST 105.06 FEET; THENCE SOUTH 19051'38" WEST 170.84 FEET; THENCE NORTH 89~7'OT' WEST 115.61 FEET; THENCE NORTH 24059'58" WEST 154.13 FEET; THENCE SOUTH 88055'16" WEST 216.17 FEET; THENCE SOUTH 19052'26" WEST 178.82 FEET; THENCE SOUTH 85017'16" WEST 320.99 FEET; THENCE NORTH 24024'25" WEST 140.61 FEET; THENCE SOUTH 86020'13" WEST 294.72 FEET; THENCE SOUTH 48049'53" WEST 102.97 FEET; THENCE NORTH 66031'21" WEST 232.99 FEET; THENCE NORTH 43002'38" WEST 241.96 FEET; THENCE NORTH 74041 '36" WEST 484.10 FEET; THENCE SOUTH 81008'09" WEST 378.64 FEET; THENCE NORTH 41039'34" WEST 426.98 FEET; THENCE NORTH 60033'37" WEST 260.44 FEET; THENCE SOUTH 78003'55" WEST 380.38 FEET; THENCE SOUTH 53016'10" WEST 2.43 FEET; THENCE ALONG THE ARC OF A CURVE, CONCAVE TO THE SOUTHEAST, HAVING A RADIUS OF 389.00, THROUGH A CENTRAL ANGLE OF 26002'14", AN ARC LENGTH OF 176.78 FEET; THENCE SOUTH 27013'56" WEST 74.74 FEET; THENCE, ALONG THE ARC OF A NON-TANGENT CURVE, THE RADIUS POINT OF WHICH BEARS SOUTH 69001 '00" EAST, CONCAVE TO THE EAST, HAVING A RADIUS OF 650.00 FEET, THROUGH A CENTRAL ANGLE OF 04029'19", AN ARCH LENGTH OF 50.92 FEET; THENCE SOUTH 16029'42" WEST 18.85 FEET; THENCE NORTH 74030'24" WEST 300.19 FEET; THENCE NORTH 67022'45" WEST 458.31 FEET; THENCE NORTH 76011'25" WEST 458,62 FEET; THENCE NORTH Sr58'44" WEST 407.40 jh Cf; b FEET; THENCE NORTH 76012'50''WEST 301.13 FEET; THENCE NORTH 81006'38" WEST 222.75 FEET; THENCE NORTH 55021'20" WEST 274.44 FEET; THENCE SOUTH 70039'55''WEST 123.83 FEET; THENCE NORTH 03008'04" EAST 558.44 FEET; THENCE SOUTH 88022'02" EAST 890.26 FEET; THENCE NORTH 01037'58" EAST 583.44 FEET; THENCE NORTH 62027'25" EAST 539.69 FEET; THENCE ALONG THE ARC OF A NON-TANGENT CURVE, THE RADIUS POINT OF WHICH BEARS NORTH 24024'16" EAST, CONCAVE TO THE NORTHEAST, HAVING A RADIUS OF 8030.00 FEET, THROUGH A CENTRAL ANGLE OF 00020'22", AN ARC LENGTH OF 47.56 FEET TO A POINT ON A REVERSE CURVE; THENCE ALONG THE ARC OF A REVERSE CURVE, CONCAVE TO THE SOUTHWEST, HAVING A RADIUS OF 1570.00 FEET, THROUGH A CENTRAL ANGLE OF 06024'00", AN ARC LENGTH OF 175.37 FEET, TO A POINT OF NON-TANGENCY, THE RADIUS POINT OF WHICH BEARS SOUTH 18020'38" WEST; THENCE SOUTH 62027'25" WEST 341.72 FEET; THENCE NORTH 75052'39" WEST 963.67 FEET; THENCE NORTH 00030'45" WEST 319.35 FEET; THENCE NORTH 00050'31" EAST 1362,44 FEET TO THE POINT OF BEGINNING. .';\. . CONTAINING 444.83 ACRES ( 19,376,631- SQ."FT.) MORE OR LESS.. I j(-{)f- ~ EXHIBIT B PIA Design Resources GHAD Boundary Exhibit 4748.1.500,01 November 1, 2006 50 rfb ~L. EM3EO INCORPORA TED DRAFT MANUEL MACHADO APN 85A-1400-001-03 EAST SA Y REGIONAL PARK DISTRICT APN 85A-2400-001-05 T.2S. 32 5 T.3S. ACCEPTED 1/4 CORNER ACCEPTED 1/4 CORNER COUNTY OF ALAMEDA 589.29'04"E 2594.67' 589.33'52"E 1115"15' CITY OF DUBLIN t, t")"" . ..,. CC\j :fl1O g~ <:: ~ .... ~ Q l5 ).. '- o ~ ~ ~ .... ~ l5 ).. '- ~ o (.) ~" ..,.C C' t")'" oq:")lg ",,"'" ....Olg ~ci;::: ~<::~ (3<<:> ~<:: ffiCl. Ci)<( 444.83t ACRES TOTAL EXISTING SCHAEFER RESIDENCE SERIES NO. 99-137918 5!~ 1:2- EAST BA Y REGIONAL PARK DISTRICT APN 85A-2400-004-01 ~ ~ ~ ~ .... ~ l5 ).. '- ~ g R.1.W. 33 34 4 3 TRACT 6765 SCHAEFER RANCH A PORTION OF SECTIONS 3 & 4, TOWNSHIP 3 SOUTH, RANGE 1 WEST, MT. DIABLO BASE AND MERIDIAN. CITY OF DUBLIN ALAMEDA COUNTY, CAUFORNIA ft~ Design Resources, Inc. '71~ PlannIng - EnglnHrlng - Surveying ~ .... ~ Q l5 ).. '- o T.2S. ACCEPTED 1/4 CORNER T.3S. R.1,W. 2700 Ygm,afo Vefley Roe(/, Suite 100 We/nut Cruk. Cefffornfe 94598-3462 SCALE: ,- " 400' TEL 1925J 210-9300 NOVEMBER, 2006 EAST SA Y REGIONAL PARK DISTRICT APN 941-0018-008 ~ ~ j ~o I 800 EAST SA Y REGIONAL PARK DISTRICT APN 941-0018-009 INTERSTA TE 580 COUNTY OF ALAMEDA EXHIBIT '8' GHAD BOUNDARY EXHIBIT SHEET 1 OF 2 LINE TABLE LINE LENGTH BEARING Lt 145.11 S48034'13"E L2 35"93 S09 "59 '09 "E L3 108"23 S16019'16"W L4 25.00 S73040'44"E L5 438.12 S41019'00"E L6 249.89 S32004'20"E Ll 497.44 S18005'49"E L8 S02.81 S02"20 '33 "E L9 176.93 S18'35'08"E LtO 178.88 SOO034'OrW Ltl 338.98 S19'09'21"W Ll2 227.S6 S84055'S4"W Ll3 174.32 SOS004'06"E Ll4 205.73 S15'29'10"W Ll5 816.74 N89042'48"E Ll6 573.68 S72"27'42"E L17 299.82 S76044'06"E Ll8 565.57 N86001'31"E Ll9 118.45 S90000'00"E L20 238.87 N52015'21"E L21 14S.72 S80 023 '31"E L22 338.94 SS7'S9'OS"E L23 324.S0 S86040'S6"E L24 479.6S S64023'41"E L25 S3.18 S37'17'{)5"E L26 54.S5 S52 046 '22"W L27 64"98 S62"26'3S"E L28 S7.82 N77'29'03"W L29 41.26 S24046'42"W L30 36.60 S79018'2rW L31 45.12 N34014'SI"W L32 386.53 S84049'OrW L33 122"22 S27'37'39"W L34 152.60 S64OS6'28"W L35 225.92 N54'OS'20"W L36 91.81 S87'40'43"W L3? 164.40 S23037'03"W P:\Orawings\03024-20 Sehaeler Ranch\Final MaplD3024-FM.dwg, 11/112006 1 :58:47 PM, Slallon e, PIA Deslgn Resources, Inc. LINE TABLE LINE LENGTH BEARING L38 195.64 S74'OI'35"W L39 204.10 N82 039 '32"W L40 2S5.59 NS3044'04"W L41 105.06 S82"18 '54 "W L42 170"84 S19051'38"W L43 115.61 N89027'OrW L44 154.13 N24'59'58"W L45 216"17 S88055'16"W L46 178.82 S19 "52'26 "W L47 320.99 S85017'16"W L48 140"51 N24 024 '25"W L49 294.72 S86020'13"W LSO 102"97 S48049'53"W L51 232.99 N66031'21"W L52 241.96 N43002'38'W L53 484.10 N74041'36"W L54 378.64 S81008'09"W L55 426.98 N41039'34"W L56 260.44 N60033'3rw L57 380.38 S78003'55"W L58 18.85 S16029'42"W L59 300.19 N74'30'24"W L60 458.31 N6r22'45"W L51 458.62 N75011'25"W L52 407.40 N8r58'44"W L63 301"13 N75012'50"W L64 222.75 N81006'38"W L85 274.44 N55021'20"W L56 123.83 S70"39'55"W L67 558.44 N03008'04"E L88 890.26 S88 022 'orE L59 583.44 NO 1037'58 "E LlO 539.69 N62"27'25"E LlI 341.72 S52"27'25"W Ll2 319.35 NOO030'45"W Ll3 2.43 SS3016'10"W Ll4 74.74 S27'13'55"W CURVE C1 C2 C3 C4 C5 C6 C7 C8 C9 C10 C11 C12 C13 EXHIBIT 'B' GHAD BOUNDARY EXHIBIT CURVE DATA DEL TA RADIUS 59.27'40" 172.50' 38'35'04" 237.50' " 28018'25" 237.50' 16'17'59" 559.94' W06'30" 450.00' 16041'54" 1175.00' 12"24'50" 1525.00' 1"50'23" 1175.00' 6"25'39" 1225.00' 26'02'14" 389.00' 0'20'22" 8030.00' 6024'00" 1570.00' 4.29'19" 650.00' LENGTH 179.02' 159.94' 109.05' 159.29' 87.24' 342.44' 330.42 37.73' 137.42' 175.78' 47.S6' 175.37' 50.92' TRACT 6765 SCHAEFER RANCH A PORTION OF SECTIONS 3 & 4, TOWNSHIP 3 SOUTH, RANGE 1 WEST, MT. DIABLO BASE AND MERIDIAN. CITY OF DUBLIN ALAMEDA COUNTY, CALIFORNIA ft~ Design Resources, Inc. '7"~ PI.nnlng - EnglnelH'lng - Surveying 2700 Ygnaolo Val/ey Road, Suite 100 Walnut Craak, CaUfornla 94598,3462 TEL (925) 210-9300 NOVEMBER, 2006 SHEET 2 OF 2 !"-..'<' t1"' -7 Z-ttSvc-- ",', ..;I 53 trtJ CZZ~ ENC3EO INCORPORATED P / A Design Resources Open Space Exhibit 4748.1.500.01 November 1, 2006 DRAFT -.-'. ""r'- I , I . I I ~G : · .' ~ ~ rJr · Y'J~~'fj ~ .~~ I V ~ ><', I 'Iff;:. '111/1. II ~, "I ::I', ..v- II 1,.~ I I ' "'~~' :;J; ) ~ 1'lTh\l dl'~ I ~,' " : ~~ ~ T,~'~ L $ ~I~~~~ ' '~/V:H- i .\\ I ~'I ,I "~ ~~. ~.~' '" ,',/,' .~ . ~ ,,' ~ · " ..' ~\ '~," VI" , I '~t~. ~\. l........... JIlJ, J' I I . rr+' LY , ~'-' ~ '- JlJ!fj, (?;. ' J-r 1r~ ~ ,..., ~\:lY. '~ 7" ~~-..;; ~ ~ ~l ~~ ~ ~ ~~!' ~ tJlh ~. ". tg~ %" ~.~ ~ I: - ( "I...~~~ LV/A ~ ~.~~..........;;~ .~~ : ,~:~~? ~~_,....~'fl~:~~~,~ ..,:~:~ ~ffm I ""-.'- t-.. )~ "O'CQ A?<...~,6lI,.' $.<S ?, '( ___ ~ ~:~ rt.:~~~_'>'~";~" '~ ! I ~ :~~~ ,=l7- -.':'{:'~ .~ t\\~~ rjJP~ ~ . ~ ~ . "'~ ~ ~ 'Ii ~ ~~'~~I~""'~~ ~~\~I: fA ~\ .~... '//);7 ~~~\\V"v l I /~f~~r_'~~nJ )?',####_--~----"" , . . : . , Of , ., , , II I I ,/ ,I ~:': ! " I j/ I . , , , , .! r- -.._~ I~ ~ ~ ~ ~ ~ ~ it DDID~~DD m .1 I II ~ ! ~ ~ ! IE ~! ~ ~ i1 I U i i ! ! H II a a ~ ~ ~I I I P I ~ .. j .. .., i j : hi : ~ I ~ a S l J ~i&> ~I \J1~ I ~ ~l\~ " t i \ ~ I l ~ !!: ~ ." ~V H~ ~a- ... H" l; z~ . 1... ag i r ~ I 8 iI II iI ~ f.l ~ :t ~ { ! J I . I . , ( . . J ~'="~ / ~W '((" y . I . , ~ ~~I , , I) I , , I , . I ----, . . o . , h t\ l : / ./ ---- -- - ~~ ~~ ~~ ~~~ ~Pliil I~ ~ ~ ~ ~ @ ~ ~ ;t ~ . ~ ~ r11 ii~ :b. ~~ ~:b ~~~ ~ I'I'i · I. !!i~ ~~rtI Ii) ~ 0'"1 !;;6~ +-- "'l"'-(~ r-8. ~ :b ii] \.S ~~, ~ i ~ ..... '- PLATE 1 PIA Design Resources Parcel Designation Plan 4748.1.500.01 November 1, 2006 f rtJ 1;~ ENGEO INCORPORATED DRAFT G.H.A.D. PARCEL DESIGNA TION PLAN CITY OF DUBLIN, CALIFORNIA DATE: AUGUST 16, 2006 PLA TE 1 Ul '/' EXIST. SCHAEFER RESIDENCE PARCEL '/' L__ Ul lk. LEGEND PARCEL 'C-1' G.H.A.D. OPEN SPACE PRESERVED WITH CONSERVA TlON EASEMENT OVERLA Y ( ZONE ~') G.H.A.D. OPEN SPACE WITH CONSERVATION EASEMENT OVERLAY (ZONE 'B') @,1i.c E.B.R.P.D. STAGING AREA WITH NO CONSERVA TION EASEMENT CITY PARK PARCELS STORM WATER DETENTION BASIN AND ACCESS ROAD Design Resources. Inc. Planning _ Engineering _ Surveying POND DEVELOPMENT SCALE: 1 If = 200 ' ~ I o 100 200 400 2700 Ygnacio Valley Road, Suite 100 Walnut Creek, California 94598-3462 TEL 1925} 210-9300 PLATE 2 ENGEO Incorporated Geologic Map of Schaefer Ranch 4748.1.500.01 November 1, 2006 51 en 't~ ENGEO INCORPORATED DRAFT ~C) ~ - ~ ~ .~ PI I ~ ~ gj !il ~ gj ~ !;1 ~ ~ III ~ ~ ~ ~ ! o ~ z uS t! ~ 8 ~ I ~ ~ B ~ ~ i * ~ ~ ~ ~ 8 ~ ~ ~ g ~ 8 ~ ~ g ~ '" 1 I '. ...t I \ . I .~, I \ J : ~ I I . "IIiI ... ~ ~ ~ ~ ~ g s i '" ~ i '" -~- ~ ~ ~ I ~ '" ~ 8 ~ ~ ~ I ~ ~ .0 ~ (I) (I) E E I- ~ ,.,,, \ ~\ ~ ~ ,~ \~~ ~ \ \ \ \\ I I I ) Ii/; 'iJ ~~ ~1~ ~~~ ~ ~)I) 1 ( ':f/ ~I )} I II I; o ~ 1/ J0' I J 'i;] 0:: 1..1 I) I,y///;I//, ~ ~~ ::a /jj;1 ~ m ~?y ,II/; ~~~----) ~ ~~ ~A. ~~ '// ' ~.~ Ii. . 9fl/I//I//' z '/ n ..f ~ i '" g ~ ~ ~ I ~ ~ E-< uS ~ ~ z i ~ ~ ~ ~ 14 ~ ::;J IS: '" <: ~ ~ ~ Jr~ ~~ f / .////// ~ Ii i;l ~ I /iA ~~ ~% eJ ~ ~ ..l ! ~ I ~ rIl ~ -- ~I i L i rl{') i i ~.J ;2j lil ~ ~ CQ A< ~ 0 ~ 1=1 S ~ ..l ..l I ~ ~ ... /,/~ /, ! !~ /; / W~ J. lIt/II 'I ('II//, z rf/; /fj) ~ /, ~ '/,/ %':/ ~ ~~ :% %~ ~~ --. 1 ~, ~ ~ !!, ~ .'; I" I II ~ \\ '~ \~;:Z ;\ \ /,~-Ft, \ ,\ II (/ I I J I- 1'[ II ~l- Il ~ "\ ~-- --.1.- z ~ ::! tl^ --- tr;&; % % ~ ~f \~\ ~~ ~~ .~ ~ ~ ~ ~ ~ ., i ~ ~ ~ ~ :;.:.~ i : ~.~ g: ~ l!'.l ~ , ~ j ';:: ~ tJ (j g; <:) tJ 0::: ~ Vi <:::'10:0" ::<( w'" ~ ... ~ ~ lli'< Z ::5 0: lil <:) O~ V) Q. ~ IIIiiiiiia.. 0: ~ ~1t<"O~ ~IUj~s II % I !5 = :Z ~ m <:) <:) 'Q3!V~Od~OONl 030N ~O 1 35N 11311I~M 553~dX 3H nOH11M 31d~30X3 ~O 031 38 11 AVrl ~ON '~3 51 M 511YJI'l ANV A8 !~Vd NI ~O III 030nOO~d3~ 38 1 N A 31'l 00 SIH . V~ ONI 30N3 A8 S OZ c) ;;;~AdOO "' o /5 ~ '" ~ v I. vi o I <0 ~ g- '0 ~ ~ Iii ~ z ~ f '" &i :~ ? '" .. " ~ 1) "" o .l: j ,/ <; IX g ;!; S !Z if '" IX ::> C> G: -' <( z ;; "' o ;::..,)t.::1' ~ 0-' -...../ ) Iju {;; L./ ENGEO INCORPORATED APPENDIX A ENGEO Incorporated Water Quality - Detention Basin Monitoring and Maintenance Schaefer Ranch, Dublin, California August 15, 2006 4748.1.500.01 November 1, 2006 DRAFT (Po UtJ'l7- Project No. 4748.1.500.01 November I, 2006 Mr. Albert Seeno III Schaefer Ranch Holdings LLC 4061 Port Chicago Highway, Suite H Concord, CA 94520 Subject: Schaefer Ranch Dublin, California WATER QUALITY - DETENTION BASIN MONITORING AND MAINTENANCE Dear Mr. Seeno: As requested, we have prepared monitoring and maintenance recommendations for three Water Quality-Detention Basins within the Schaefer Ranch development property in Dublin, California. This is intended as a working document for use during maintenance of the water quality- detention basins. The basins are designed as water quality and detention facilities to control peak flood flows from the site. Maintenance of the basins will include, but not be limited to, erosion/slope protection, vegetation management, sediment accumulation, trash/debris removal and inspections of the inlet and outlet structures. The detention basins will be owned and maintained by the Schaefer Ranch Geologic Hazard Abatement District (GHAD). Weare pleased to have been of service to you on this proj ect and are prepared to consult further with you and your design team. Very truly yours, ENGEO INCORPORATED Prepared by: Reviewed by: J. Brooks Ramsdell Senior Engineering Geologist Theodore P. Bayham Principal Engineer fa \ ~'Z2- ENGEO INCORPORATED INTRODUCTION................................ ............................................................................. ............ 1 Monitoring Schedule................................. ..................... .............................................. ........... 2 General Maintenance and Monitoring..................................................................................... 3 Inlet and Outlet Structures...................... .................................. ................. ....................... 3 Detention Basin Embankments............................ ...................................... ............ .......... 4 Vegetation...... ........................................ ................. ......... ................................................. 4 Maintenance of Access Roads.......................................................................................... 4 Fencing Repair........ ........ ..................... .................... ........ ............... .................................. 5 Mosquito Abatement...................................................................... ............ ........... ........... 5 Desilting and Clearing of Basin....................................................................................... 5 Detention Basin Catchment Area Inspection and Monitoring ......................................... 6 Emergency Response and Scheduled Remedial Repair .......................................................... 6 MONITORING REPORT &?- UV~2- ENGEO INCORPORATED INTRODUCTION The purpose of this document is to provide a framework for the management and maintenance of the Water Quality - Detention Basin at the Schaefer Ranch development. The three detention basins are located throughout the Schaefer Ranch development property-one being near Dublin Boulevard on the western edge of the property, one being near Dublin Boulevard in the south- central portion of the property, and one east of 'Road A' on the eastern portion of the property. The detention basins will be used to mitigate peak flows from the surface runoff on the subject site. Basin A is located in the western portion of the development, directly north of Dublin Boulevard. The surrounding northwestern to eastern slopes serve as inlets for the detention basin. The outlet for this basin is centrally located on the southern boundary of the basin, and runs westerly. Interior slopes for the basin are planned to be up to 30 feet high with a slope gradient of 2: 1 (horizontal:vertical). An approximately 15-foot-wide bench extends around the top of the debris basin berm on the south western boundaries of the basin. Slopes on the other side of the road are proposed at a 2.5: 1 gradient, sloping down to the west. Slopes to the east of the basin are at a 2:1 gradient, and are approximately 30 feet high. Basin B, consisting of a water quality basin and a detention basin, is located in the south-central portion of the development between Schaefer Road and Dublin Boulevard. The inlets for Basin B are located northeast and east of the basin. The outlet for this basin is centrally located on the western boundary of the basin, and runs westerly. The outlet for Basin B discharges into a new closed conduit system. Interior slopes for the basin are planned to be up to 30 feet high with a slope gradient of 3:1 (horizontal:vertical). An approximately 15-foot-wide bench extends around the top of the debris basin berm on the south and western boundaries of the basin. Basin C, consisting of a water quality basin and a detention basin, is located on the eastern portion of the development, directly southeast of Road' A.' The inlets are centrally located on 4748.1.500.01 November 1, 2006 DRAFT 1 1.o3~7- ENGEO INCORPORATED the western side of the basin. The outlet for this basin is located on the northern point of the basin, and runs northwesterly. The outlet for Basin C discharges into a new closed conduit system. Interior slopes for the basin are planned to be up to 40 feet high with slope gradients of 2.5: 1 (horizontal:vertical). Monitoring Schedule Quarterly monitoring during January, April, July and October is planned, with additional monitoring within two working days after significant storm events (i.e. one inch of rainfall in a 12-hour period). Technicians retained by the GHAD will carry out site inspections and utilize the Monitoring Report Form included at the back of this manual. Personnel and subcontractors involved in detention basin management will be trained on reading the staff gauge, proper pruning/cutting techniques, and inspection measures by the GHAD. A sample Inspection Report is included at the end of this letter. Each water quality basin has been designed to meter out detained runoff over 48 hours when the basin water surface elevation is at the side opening flowline of the inlet pipe riser/overflow structure. At this water surface elevation, residence time longer than 48 hours could be an indication of sediment buildup (resulting in loss of actual water storage volume) or blockage of outlet pipe. In this case actions should be taken to investigate the cause and corrective actions should be implemented. Sediment accumulation measurements will monitor the rate of sedimentation quarterly in the detention basin and identify the need for removal. Some sedimentation is expected within the basin; however, removal is planned only to the extent necessary for proper basin function. 4748.1.500.01 November 1, 2006 DRAFT 2 lJ; L\ frb ~2. ENGEO INCORPORATED General Maintenance and Monitoring Procedures for the following maintenance and monitoring items are presented in the following section: . Inspection and repair of inlet and outlet structures. . Stabilization and/or repair of eroded areas or failures of the embankment surrounding the Detention Basins. . Pruning/cutting of the vegetation within and surrounding the Detention Basin. . Maintenance of all access roadways. . Monitoring any perimeter fencing for public safety. . Mosquito Abatement. . Sediment accumulation measurement and removal. Inlet and Outlet Structures. Maintenance of inlet and outlet structures will involve the clearing of debris and repair of the trash rack structure, as required to allow passage of storm flows. The inlet and outlet structures should be observed during or immediately after large storm events to avoid prolonged blockage. Any observed damage or apparent inoperability of the structures will be reported to the GHAD Manager immediately. In the event that the primary detention basin outlet is rendered inoperable during a major storm event, the emergency overflow spillway should be allowed to operate as designed to pass the storm flows. Emergency maintenance of the inoperable outlet structure should be undertaken at such time, and with the equipment, that the GHAD Manager deems appropriate. 4748.1.500.01 November 1, 2006 DRAFT 3 tJ 5 r:t&2--- ENGEO INCORPORATED Detention Basin Embankments. Maintenance shall involve observation of the detention basin embankment. The detention basin slopes should be inspected for obvious signs of vertical and/or horizontal displacements. All embankment sides should be free of erosion, rills, slumps or landslides. Any observed slope displacement should be reported to GHAD Manager immediately. Any irrigation systems are to be monitored for proper function. Leaking or malfunctioning irrigation systems will be repaired within two days of inspection. Vegetation. Vegetation that does not preclude the proper functioning of the Detention Basins should be allowed on the floor of the basin to aid in the trapping of sediment. Although vegetative growth is generally encouraged, excess vegetation (defined as shrub and tree growth in excess of 5 feet in height) must be removed from the basin floor by pruning. Herbicides will not be used in the basin unless absolutely necessary. Such use shall be governed by all applicable rules and regulations. Vegetation removal will be accomplished by prumng with hand labor, unless aggressIve, non-native species become pervasive, in which case other methods of removal can be initiated at the discretion of the GHAD Manager. Activities will involve only the cutting and removing of vegetation above the ground, e.g. mowing, rotary cutting, and chains awing, where the activity neither substantially disturbs the root system nor involves mechanized pushing, dragging, or other similar activities. No heavy equipment will be used within the detention basin for routine vegetation control. The pruning debris will be removed from the basin in burlap or canvas bundles and trucked to an authorized dumpsite reviewed and approved by the GHAD Manager. Vegetation removed or destroyed during maintenance will be allowed to re-establish naturally without replanting. Maintenance of Access Roads. Maintenance of access roads and top ofberrn bench, as shown on the improvement plans, will involve repair of excessive bumps, cracks and depressions such that maintenance vehicles can easily navigate the roads. The roadways will be inspected on a 4748.1.500.01 November 1, 2006 DRAFT 4 l.4 lp f1[f6 v ENGEO INCORPORATED semi-annual basis and repaired as needed. Any damage to or failures of the embankments near the road will be reported to the GHAD Manager immediately. Fencing Repair. Maintenance of fencing involves repair of all gaps, tears, sags and breaks such that public safety is provided. All perimeter fencing will be monitored quarterly and maintained in good condition without breaks or damage. Mosquito Abatement. It is possible that mosquito abatement will not be required in the water quality/detention basins due to the drying cycle in the summer months; however, if homeowner complaints are received by the GHAD, the GHAD will contact Alameda County Vector Control. Desilting and Clearing of Basin. Detention basin floors must be regularly cleared of excess sediment and excess vegetation to enable proper flow characteristics. Failure to do so can create flood hazards. The floor of the detention basin should be monitored on a semi-annual basis. If sediment in excess of 18 inches or 10 percent of the storage capacity, whichever is greater, has accumulated above design grades, the sediment should be removed. Sediment accumulation will be measured with installed staff gauges. If vegetation in excess of 5 feet in height is present, it will require removal as described in the Vegetation section. Vegetation accumulation will be measured with a tape measure in at least four locations within the basin floor. Prior to sediment removal or vegetation pruning, the procedure should be reviewed and authorized by the GHAD Manager. If sediment in excess of 18 inches or 10 percent of the storage capacity, whichever is greater, has accumulated above design grades, sediment removal shall be undertaken before the next winter season. The dry season is the preferred time of year for sediment removal. Sediment removal for routine maintenance will be with small mechanized equipment, hand labor and wheelbarrows as much as possible subject to compliance with regulatory agency requirements. Emergency repairs may require use of larger equipment including, but not limited to, excavators. Sediment 4748.1.500.01 November 1, 2006 DRAFT 5 li~~~ f) A CZ -2,- I..J ENGEO INCORPORATED will be removed in small sections, with as little disturbance to existing vegetation as possible. No heavy equipment will be used within the detention basin without permission from the GHAD Manager. The sediment should be disposed of in a legal manner. In general, due to the steepness of the site, limited areas will be available to place the material from the detention basin on open space areas of the parcel and any proposed disposal areas should be reviewed by the GHAD Manager in consultation with a qualified biologist as necessary. The sediment will not be placed within 20 feet of a creek or drainage. The sediment will not be placed on sloping ground, or any area of sensitive wildlife habitat. After spreading, the sediment will be hand seeded and covered with straw mulch. Detention Basin Catchment Area Inspection and Monitoring. Monitoring of the detention basin shall involve visual inspection of the detention basin containment area and piezometer measurement if installed. The detention basin catchment area should be inspected for obvious signs of vertical and/or horizontal displacements. The base of the detention basin should be free of erosion, rills, slumps or landslides. Emergency Response and Scheduled Remedial Repair Emergency response and scheduled repair expenditures are to be prioritized at the discretion of the GHAD Manager based upon available funds and the approved operating budget. When available funds are not sufficient to undertake all of the identified remedial and preventive stabilization measures, the expenditures are to be prioritized as follows in descending order of priority: A. Prevention, mitigation, abatement or control of hazards that have either damaged or pose a significant threat of damage to the detention basin embankments or spillway. 4748.1.500.01 November 1, 2006 DRAFT 6 I'" ([1 t> 0/112/ ..J ENGEO INCORPORATED B. Prevention, mitigation, abatement or control of hazards which have either damaged or pose a significant threat of damage to ancillary structures, including but not limited to the inlet and outlet pipes. C. Prevention, mitigation, abatement or control of geologic hazards which have either damaged or pose a significant threat of damage to the detention basin. The techniques which may be employed by the Schaefer Ranch GHAD to prevent, mitigate, abate, or control hazards include, but are not limited to, the following: 1. Repair, maintenance or replacement of inlet or outlet control valves and structures. 2. Stabilization (either partial or total) of levee embankments by removal and replacement with compacted, drained fill. 3. Construction of erosion control measures. Whenever feasible, bioengineering techniques will be utilized and are preferred over hard armor. 4. Placement of subsurface drainage devices (e.g. underdrains, or horizontal drilled drains). 5. Slope correction (e.g. gradient change, slope trimming or contouring). 6. Construction of additional surface ditches and/or detention basin, sediment traps, or backfill of eroded channels. 4748.1.500.01 November 1, 2006 DRAFT 7 ,,,\ .~ ;.' .t{!j'/;/ v ENGEO INCORPORATED MONITORING REPORT Schaefer Ranch Dublin, California WATER QUALITY - DETENTION BASIN OPERATIONS AND MAINTENANCE SITE MONITORING AND MAINTENANCE REPORT FORM (TO BE COMPLETED QUARTERLY IN JANUARY, APRIL, JULY AND OCTOBER AND AS NECESSARY DURING HEAVY RAINFALL) Inspector: Weather Conditions: Days since last rainfall: Basin Water Level: Date: Dry season? _ Wet season? Sediment Accumulated since Last Monitoring Event MONITORED YES NO N!A COMMENTS! SUGGESTED MAINTENANCE CONTROL 1. Are inlet and outlet structures functioning properly, allowing the basin to drain and are they in satisfactory condition? 2. Are access roads in satisfactory condition? 3. Is all perimeter fencing in good condition without breaks, gaps or damage? 4. Have the debris racks been cleaned and are they in good condition? 5. Are embankments surrounding the basin in good condition without rills or failures? 4748.1.500.01 November 1, 2006 DRAFT j/,,; 1-) .' U IY' ENGEO INCORPORATED MONITORED YES NO N!A COMMENTS! SUGGESTED MAINTENANCE CONTROL 6. Is the vegetation less than 5 feet in height? 7. Are embankment slopes protected with mulch or vegetation? 8. Has sediment removal been undertaken in the last 3 months? 9. Is there evidence of chemical sheen or odor, contaminated runoff, litter or blowing debris in or near the basin? 10. Do any basin devices require maintenance to provide more effective function? 11. Are there signs of leaking irrigation systems? 12. Are there any signs of vandalism? 13. Are mosquitoes evident? 14. Has mosquito abatement been undertaken since the last monitoring event? 15. Are there remedial/repair tasks that should be undertaken in the near future? 4748.1.500.01 November 1, 2006 DRAFT '11 Jh~'I/ ENGEO INCORPORATED MONITORED YES NO N/A COMMENTS! SUGGESTED MAINTENANCE CONTROL 16. Is there evidence or information received in the last 3 months to indicate a lengthy drain time? "No" answers to Items 1-7 or "Yes" answers to Items 8-16 require a corrective action noted on Page 3. 4748.1.500.01 November 1,2006 DRAFT WATER QUALITY - BASIN OPERATIONS AND MAINTENANCE SITE MONITORING AND MAINTENANCE REPORT FORM (CONTINUED) CORRECTIVE ACTIONS UNDERTAKEN (If none required, enter date and "none") 12rro 1'~ ENGEO INCORPORATED DATE DEFICIENCY NOTED CORRECTIVE ACTION 4748.1.500.01 November 1, 2006 DRAFT I ~ OOzz- ENGEO INCORPORATED I DATE I DEFICIENCY NOTED I CORRECTIVE ACTION I 4748.1.500.01 November 1,2006 DRAFT l~aoZ ENGEO INCORPORATED APPENDIX B ENGEO Incorporated Site Geology 4748.1.500.01 November 1,2006 DRAFT ! 5 rf(j2/ ENGEO INCORPORATED Site Geology Regional geologic maps of the area have been prepared by Dibblee (1980), Crane (1988) and Graymer (1996). The most recent regional map prepared by Graymer indicates that the site is underlain by late and middle Miocene rocks of the Briones Formation and undivided middle Miocene marine rocks of the Monterey Group including the Rodeo Shale, Hambre Sandstone, Tice Shale and Oursan Sandstone. Major folds in the site vicinity include the Kaiser Creek Syncline and the Knife Anticline, located north of the property, as shown on Plate 2. Two smaller unnamed folds that form a syncline-anticline pair are present on the south limb of the Kaiser Creek Syncline as shown on Plate 2. The axis of the syncline passes through the center of the Schaefer Ranch Property in a northwesterly direction, trending along the center of Marshall Canyon, passing through the ridge under Donlan Point (the "axis" is the center line of the fold; beds dip in opposite directions on either side of the fold axis). The synclinal axis extends to near the south site boundary, passing below the proposed Dublin Boulevard Extension. In the site vicinity, the major folds are commonly associated with low-angle compressional faults known as "thrust faults", including the Bollinger and Miller Creek Faults (Crane, undated, Dibblee, 1980, and Wagner, 1976). The thrust faults are thought to be the result of the same regional compressional forces that have caused the folding of the rocks in the East Bay Hills block. None of the thrust faults mapped in the site vicinity are considered to be active by the State. Detailed mapping of the property included within the GHAD boundaries was completed as part of the Geotechnical Investigations completed by AKA (1997) and ENGEO, Incorporated (2004). The results of these investigations are included in the geologic descriptions. 4748.1.500.01 November 1,2006 DRAFT Lorlfv ENGEO INCORPORATED Geologic Units Undocumented Fill. There are existing undocumented fills on the property associated with stock ponds, roads, and existing structures. The most extensive undocumented fill deposit appears to be at the entrance to the property at Schaefer Ranch Road. Approximately 25 feet of stiff clay interpreted to be undocumented fill was encountered in this location. It appears that this fill is likely associated with the construction of the adjacent Interstate 580. Proposed remedial grading includes the complete removal and replacement of this undocumented fill as well as other less extensive undocumented fill deposits on the site within the grading limits of the project. Alluvium. Most of the creeks typically have steep, V -shaped channels incised into bedrock or landslide debris, with no significant alluvial deposits. Minor deposits of modern alluvium associated with the existing creeks occur in the lower reaches of Marshall Canyon and Wagon Wheel Canyon. These deposits appear to consist of 10 to 20 feet of relatively compressible, sandy to gravelly clay. A more significant deposit of alluvium occurs at the entrance to the property at Schaefer Ranch Road, where the base of the stiff silty to sandy clay was encountered at 35 feet and 45 feet below the surface. A soil deposit identified as an old alluvial terrace occurs along the existing entrance road on the south side of the ridge, and is well exposed in a deep erosion gully. Exposures in the gully consist of stratified silty sand with pebble lenses. ENGEO and AKA borings in the terrace deposit record thicknesses varying from less than 10 feet to 44 feet. The deposit is dense and relatively incompressible. Residual Soil and Colluvium The site bedrock is typically mantled with 3 to 5 feet of residual soil formed from weathering and decomposition of the underlying bedrock. The weathering of the bedrock on the site 4748.1.500.01 November 1, 2006 DRAFT '\ \. tl(j~I/ ENGEO INCORPORATED typically produces a fine-grained soil containing expansive clays. Colluvium is a soil deposit formed from downslope movement and deposition of residual soil by such processes as slopewash, sloughing/shallow sliding and creep. Mappable deposits of colluvium (typically thicker than 5 feet) occur in most swales and ravines and at the bases of many slopes on the property. The colluvium typically consists of expansive silty clay with rock fragments. The composition of the colluvium varies with the composition of the underlying bedrock. Within swales, the colluvial deposits tend to be relatively thicker and may be subject to flow or slip downslope. Landslides Landslide deposits consist of masses of unconsolidated material and!or bedrock that have moved downslope by sliding, falling, or flowing. Many landslides, ranging in size from very small to large, occur on the site. The landslides include earth flows, debris flows, bedrock slumps and translational landslides. Shallow (less than 5 feet thick) to moderately deep (5 to 20 feet thick) earth flows are the most prevalent types of landslide at the site. Shallow landslides occur on the steeper slopes, along drainages and in swales. Larger, deep (greater than 20 feet) and deep-seated landslides (greater than 30 feet) were also identified at the site. Bedrock Upper Miocene Marine and Nonmarine Sediments, Undifferentiated The rocks underlying the center of the syncline, on the southwest side of Marshall Canyon, appear to consist of interbedded claystone, siltstone and clay-cemented sandstone, including both marine and nonmarine deposits. This unit was previously mapped by Dibblee (1980) as Pliocene nonmarine rocks and by Graymer (1996) as "unnamed Miocene continental rocks". The 4748.1.500.01 November 1, 2006 DRAFT I ~ [J'tJ6 t/ ENGEO INCORPORATED sandstone and siltstone units are weak to moderately strong and highly to moderately fractured. Based on our experience with this mapped unit in the site vicinity and in projects to the north, we would expect that it could contain occasional layers of weak, relatively expansive claystone. Briones Formation The marine Briones Formation, which underlies the upper portions of the highest site ridges, consists mainly of brown, thickly-bedded, moderately-strong to strong, clay-cemented, fine- to medium-grained lithic sandstone. Some units contain minor thin beds of siltstone, friable sandstone and pebble conglomerate. The most resistant beds in the Briones Formation are gray-brown, strong to very strong, carbonate-cemented, medium- to coarse-grained sandstone that contains abundant shell fragments. Miocene Marine Sediments In the south and east portions of the property, the slopes are underlain by interbedded marine sandstone and siltstone of the undivided Monterey Group. As mapped by Dibblee (1980) this unit is divided into an upper unit of sandstone with interbedded siltstone (Tmss) and a lower unit consisting mainly of siltstone with minor interbedded sandstone (Tmsl). The sandstone is thickly bedded, brown, weak to moderately strong, fine grained and clay cemented. The near-surface exposures of sandstone are moderately to highly fractured; fracture spacing decreases with depth. The siltstones are gray-brown to gray, massive to thinly bedded and weak. The siltstone locally grades to clayey siltstone and claystone. 4748.1.500.01 November 1,2006 DRAFT I q tJ61;-~ ENGEO INCORPORATED Groundwater At the time of subsurface work groundwater has been encountered between 12 to 30 feet below the ground surface. In general, the shallow groundwater was encountered locally within areas of colluvium or deeply weathered bedrock. This water appears to be perched on the underlying bedrock. Fluctuations in groundwater levels may occur seasonally and over a period of years because of precipitation, changes in drainage patterns, irrigation and other factors. Future irrigation may cause an overall rise in groundwater levels. Seismic Sources The seismicity of the Bay Area is dominated by the major active strike-slip faults. No State of California-zoned active! faults are mapped crossing the GHAD property. The nearest State of California-zoned, active2 faults are the Calveras fault located approximately 1 mile northeast of the site and the Hayward Fault located approximately 6 miles southwest of the site. The Dublin fault, a local strike-slip fault that passes 2,500 feet east of the property, is not considered active by the State.. The Working Group on Northern California Earthquake Probabilities (WGEP, 2003) recently evaluated the seismicity of the Bay Area. The WGEP estimated a 30-year probability of a moment magnitude (Mw) 6.7 earthquake on one of the active Bay Area Faults of 62 percent. The 30-year probability of a 6.7 Mw earthquake for the Calaveras and Hayward Faults were estimated at 11 percent and 27 percent, respectively. As discussed in the geotechnical investigations, there J An active fault is defmed by the State Mining and Geology Board as one that has had surface displacement within Holocene time (about the last 10,000 years) (Hart, 1994). The State of California has prepared maps designating zones for special studies that contain these active earthquake faults. 4748.1.500.01 November 1,2006 DRAFT /"~,'7 1:. V""- i", Uf.., ENGEO INCORPORATED is a high probability that the site and any improvements will be subject to strong ground shaking and some deformation of the site slopes during the lifetime of the project. 4748.1.500.01 November 1,2006 DRAFT EXHIBIT B NOTICE OF PUBLIC HEARING 6'q)6& EXBIBIT ~ To the Resolution <62.ub1)~ NOTICE OF PUBLIC HEARING ON FORMATION OF THE SCHAEFER RANCH GEOLOGIC HAZARD ABATEMENT DISTRICT You are hereby notified that on December 5th, 2006 at 7:00 p.m. in the City Council Chambers at 100 Civic Plaza, Dublin, California, 94568, the City Council of the City of Dublin will consider the formation of the Schaefer Ranch Geologic Hazard Abatement District ("Schaefer Ranch GHAD") pursuant to the attached "Petition for Formation of the Schaefer Ranch Geologic Hazard Abatement District Pursuant to Division 17 of the Public Resources Code of the State of California" (the "Petition"). The territory proposed for inclusion in the Schaefer Ranch GHAD is located in the area generally known as Schaefer Ranch, and is described in detail in the Petition. The formation of the Schaefer Ranch GHAD will require the levy of an assessment to pay for the costs and expenses of the activities described in the plan of control for the Schaefer Ranch GHAD ("Plan of Control"). The Plan of Control can be reviewed at City Hall at the address set forth below. The Plan of Control may be duplicated at cost upon request. The purpose of this hearing is to receive and consider any and all objections to the formation of the Schaefer Ranch GHAD. Valid objections can be made in writing, not later than the time set for hearing, by any owner of real property within the boundaries of the territory proposed for annexation. Objections shall contain a description of the land by lot, tract and map number, and shall be signed by the owner of such property. Objections must be mailed or delivered to the address set forth below and must otherwise comply with the provisions of Public Resources Code Section 26564. For further information contact Frank Navarro, Senior Civil Engineer, at 100 Civic Plaza, Dublin, CA 94568 or at (925) 833-6630. City Clerk, City of Dublin