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HomeMy WebLinkAbout4.4 TOWN OF LOS ALTOS HILLS June 5, 1995 Staff Report to the Planning Commission RE: MITIGATED NEGATIVE DECLARATION AND TENTATIVE TRACT MAP,LANDS OF LINDY PROPERTIES I; 27591 PURISSIMA ROAD FROM: Sheryl Kolf,Assistant Engine r". Michael A. Porto;Interim Planru irector RECOMMENDATION: That the Planning Commission: 1. Recommend approval of the Mitigated Negative Declaration with the revised Mitigation Measures, .recommend approval of- the Draft Mitigation Monitoring Program, and recommend approval of the Proposed Tentative Tract Map including the attached findings and conditions of approval, as recommended by Staff,to the City Council. BACKGROUND: The review period for the attached Mitigated Negative Declaration for the proposed Deer Creek Subdivision ended May 31, 1995. All letters addressing the Mitigated Negative Declaration that were received'up to that date have.been included at the end of this report The Planning Commission's responses and the public's responses to the Mitigated Negative Declaration have been summarized to include the results of studies that have been performed since the initial preparation of the Mitigated Negative Declaration (see attached Responses to Mitigated Negative Declaration, Deer Creek Subdivision). A Draft Mitigation Monitoring Program hasalso been prepared that addresses the concerns of the Planning Commission and the public (see attached Deer Creek Subdivision Draft Mitigation Monitoring Program). DISCUSSION - At the Planning Commission meeting on May 10, 1995, the Planning Commission reviewed the'Mitigated Negative Declaration for this proposed subdivision and also gave initial comments for the Tentative Map. Listed below are the items of concern that were raised and the applicant's responses: Proposed "Samuel Lane" revised to Brubaker Lane": The applicant was asked if there was a hitorical'street name that could be proposed -for this subdivision rather than his initial proposal of "Samuel Lane". It was suggested that the owners of the property from the'.late 1890's, the Brubakers, might be a suitable name for the proposed street. The applicant stated that he would have no objections to this name. 4 . Lands of Lindy Properties I,Dee Creek Subdivision t June 5,1995 Page 2 • The City of Los Altos Fi e Department was consulted to see if this name was acceptable to them. Stu Fa well checked the name of,"Brubaker Lane" and found it to be'acceptable. The Town Historian, Ros-mary Meyerott, was also consulted about this name selecthoughion t ht tha andt he agreed t i at it would bean especially all�nid ce tribute e very to r�priate for Brubaker is property. She gp Y The appropriate conditio . of_approval have been amended to reflect the name Brubaker Lane. Th• .1 c•m-n of h• he • i - f,rLs Le in .I - w. i• - • _ D• -r • le The applicant was questio ed as to why the house site for the proposed Lot No. 3 was placed on the west si o e of:Deer Creek rather than the east side of the creek where it would be farther fr.m Purissima Road. The house site for Lot No. , was initially submitted to the Town shown on the east side of Deer Creek. The ap•licant had chosen this area so that the house would have the buffer of Deer Creek be' . een it and Purissima Road. According to Town policy, this site on the east side o the creek was not appropriate because the proposed leachfields would have b-en located at an elevation that was. higher thanthe probable house pad eleva on (although the primary leachfield would have been able tobe located on the o•posite side of the creek, the secondary leachfield would have been located on the s-;me side of the creek as the house site at an elevation higherthan the.probable ho se pad). The proposed house site would also have been located directly below the •roposed leachfields for Lot No. 1. The applicant was informed at this initial mee n ng that Lot No. 3 must meet both of the Town's policies if it was to be considered a •uildable lot. Lot No. 3 that is shown on he Tentative Map has a proposed secondary leachfield on the same side of the creel that is located at approximately the same grade as the probable house pad. In or.er for this site to meet the Town's policy, the house pad would need to be built u. so that it'would be at a higher elevation.than the leachfield. T*e leachfields or Lot No..1 are no longer a concern for Lot No. 3. As designed,Lot No. 3 meets t e Town's criteria for leachfields and house locations. Is the survey an aerial surv.y or a field survey? The survey for this Tentati e Map is from a field survey performed by Bay Area . Consultants. The surveys d at are performed for future site development permits should.be_similar.to this s vey and, should have nearly identical slope density calculations. Concern about flooding.of of No. 3: Santa Clara Valley Water 1 istrict, the Town's flood control district, reviewed the proposed Tentative Map for this project in January 1995. Based on their review, they Lands of Lindy Properties I,Deer Creek Subdivision June 5,1995 Page 3 stated that for this'entire project site, minor flooding in a 100 year.storm could be expected that would extend approximately 25 feet from the top of bank of Deer Creek. The conservation easement that is proposed for Deer Creek extends to these limits so that any structures developed on Lot No. 3 (and on Lots No. 1 & 2) should not be affected by a 100 year storm. Revised Condition No. 29 addresses_the storm drainage design for the subdivision and requires the applicant to verify that the existing creek has the capacity to handle a 100 year storm. If it is found'thatthe creek'is not adequate as it exists, the applicant will be required to improvethe'creek as necessary. Concerns that the drainage from the properties located above the project site may become subsurface flows and then may resurface on this project site: There has been some question as to whether the storm waterfrom the sites above this site become subsurface flows and then resurface on the project site. There was also a concern 'that there may be a spring located on this project site. The geotechnical investigation performed'byi Terrasearch did not produce any evidence of a spring on this.site. Drainage in the vicinity of Lot No. 1 was evaluated by the project engineer. The natural drainage swale enters the property from the northeasterly corner and then flows to Deer Creek. This swale carries the storm water from sites located above the project site. There are not any improvements or grading proposed where this swale enters the project property and so the' swale will remain as a natural drainage channel. The project soils engineer has recommended that a subdrain be installed across the axis of this drainage swale to intersect any subsurface:seepage:water that may be following the same alignment as the swale. In the future, when Lot No. 2 is developed, the swale would most likely'be intercepted by the driveway. The swale could be regraded at that time to to follow the'edge of the driveway in a similar configuration to its existing course. The swale would then be allowed to transition intosheetflow, similar to the existing.transition of the natural swale into sheetflow. The region that would be'affected by the sheetflow over Lot No. 3 is not over the proposed building site but rather over a proposed leachfield site. Sheetflow over the leachfield is not a problem as long as the system is installed properly as has been addressed in revised-Condition No. 26. Bridge construction arid right of way-improvements Reimbursement Agreement: The applicant has requested that the Town allow for a Reimbursement Agreement - for the costs to retrofit.or reconstruct'theaccess bridge and the costs of the improvements that are made within the public right of way for.;Brubaker Lane.. The reimbursement to the applicant would come from the property owner at 27575 Purissima Road in the event that the property subdivides. The property at 27575 Purissima Road. is required to access off the bridge and road that is being constructed with this subdivision in order to limit the accesses off of Purissima Lands of Lindy Properties I,Dee Creek Subdivision June 5,1995 Page 4 Road. The right of way for Brubaker Lane is required to be 60 feet wide so that the right of way may accommo•ate a future subdivision of 27575 Purissima Road. The City Attorney has su;gested a time limit of 10 yearsfor the Reimbursement Agreement. Condition No. 17 has been added to address this item. Abandonment of the existing access easement along the southerly property line: In a document that was s bmitted to the Town, the access easement along the southerly property line is r-ferred to as a tool forfuturebargaining. The applicant has requested that he be al •wed to retain this easement so that he will not lose this bargaining tool. The slope •ensity calculations for Lot No. 2 will be revised slightly due to this access easement and are shown below. The following table includ:s an analysis of Lot No. 2,with and without the existing access easement, and th- corresponding Lot Unit Factor (LUF), Maximum Development Area (MDA) :nd Maximum Floor Area (MFA) as required by Sections 10-1.502 and 10-1.503 of the Town of Los Altos Hills Zoning Ordinance. TABLE 1 Lot# Net Ac es Ave. Slope . LUF MDA MFA 2 w/emt 1.22 17.3% 1.023 . 12,545 5,765 2 w/o emt 1.27 17.2%. 1.083 13,320 6,108 Source: Jennings,Mc P ermott,Heiss,Inc. Since retainin the easeme t does not create a:lot'with a LUF less than 1.00, Staff recommends allowing the :asement to remain at this time. The easement would be abandoned at some time i the future if the property to the south of this project subdivides. Does the noise study t at was performed for this subdivision include measurement' from the higher portions of the property? The noise study for this subdivision was performed by Illingworth & Rodkin, Inc. The measurements for the study were taken at 7 locations on the property including locations on each of the proposed lots, the highest porion of the property,the lowest portions of the property, and at the creek bed. A copy of thenoise study has been • included with this report. A study of the neighboring properties was requested so that the overall effect on the neighborhood could be reviewed; In the northerly direction, directly adjacent to this property is a developed 12 acre parcel of land which has two''lots and is currently under review by the Town for a lot line adjustment: Beyond those parcels is the Rhoda Drive subdivision which • Lands of Lindy Properties I,Deer Creek Subdivision June 5,1995 Page 5 3.3 acre parcel of developed land. Further to the south and to the eastof this property is the Canario Way subdivision which consists of 13 lots ranging in size from 1.0 to 1.5 acres. To-thewest of this property-is Interstate 280, the Town's Corporation Yard and the Town's Little League fields; It.appears that the proposed 3 lots for this subdivision, eachofapproximately 1.2 acres, conform to the existing neighboring properties., Acceptability of the leach field design by the Town Geologist and Santa Clara County Department of Environmental Health: The Town Geologist has had the :opportlunity to, review this subdivision and the supplemental information that wash requested from the applicant. The final comments from the Town Geologist, dated May 5, 1995, include two conditions of approval for the project. These conditions are shown as revised Conditions No. 12 and 13. The results of the final review by Santa Clara County Department of Environmental Health as indicated in the letter from Linda Crawford dated May 5, 1995,have been shown in the revised Conditions No. 30a,30b and 30c. These requirementswill also be required to be included in the CC&R's for the subdivision as.indicated in revised Condition No. 16. Construction of the sanitary sewer leachfields; Some concerns were raised about the construction of the sanitary sewer leach fields- so that they would maintain the drainage qualitiesthat currently exist. Specifically, the surface drainage currently is separated from the subsurface flow through the gravelly layers by a clay layer. The installation of the leachfields are not anticipated to create any drainage problems as long as the septic systems are installed properly. In order to prevent the surface storm flow,from entering these lower gravelly layers in the location of the leachfields,it will be!necessary to ensure proper construction of the leachfields. Revised Condition No. 26 has been changed so that it also includes review and approvalofthe construction 'of the leachfields to the satisfaction of the Town Geologist and City Engineer. Pathway easements and construction along the northerly and easterly property lines: The applicant voiced some concerns over the pathway easement that was requested over the easterly property line since it would require construction through the natural drainage swale in that location. The applicant was also concerned about people along the pathway being able to look directly into a future house on Lot No. 1. It was suggested that this property only be required to grant an easement along the northerly property line •and that the other connections to this'property that would not require crossing the drainage swale will be obtained when possible in the future. Revised Condition No. 35 has been changed so that the type lib pathway will be required to be constructed along P;urisima Road and a native pathway will be cleared along the northerly property line. The condition has also been changed so a 4 Lands of Lindy Properties I,Deer Creek Subdivision r June 5, 1995 Page 6 that the additional 30' wi•e portion of pathway easement will not be required from this property alone but w' instead be divided so that this property will grant 15 feet and the adjacent property to the north will grant 15 feet at some time in the future. The applicarit will still be required to construct the footbridge over Deer Creek for the pathway but will not •e required to install the switchbacks. The switchbacks will not be a le to be cons. ucted until the additional pathway easement is granted to the Town by the proper, to the north. Concerns were expressed :bout cultural resources on the project sitez While there is no knowle•ge of a prehistoric or historic archaeological site on this property, Condition No. '6.has been added to address this topic in the event that evidence is uncovered d 'ng the construction of the subdivision improvements. Will there be any signific.nt impacts to plant life as a result of this project: The applicant has had a b 0 tanist, Taylor Peterson with Thomas Reid Associates in Palo Alto, vist the project .ite to review the impacts.Ion the plants. The report found that the site had already be-nhighly disturbed and so there were not any rare plants or rare plant habitats at the site. She found only common plants on the site. There is a riparian habitat ti ough Deer Creek that has been dominated by the Coast Redwoods that have bee planted there. The creek bed is dominated by Vinca which isa non-native,inva.ive species. The rest of the site is covered ma non-native annual grassland that is i terspersed with native and ornamental trees. The only significant trees that are e pected to be affected by this subdivision are one Coast Live Oak tha maybe affec ed by the construction of the leachfield for Lot No. 2 and two Coast Redwoods that ill be removed for the construction of the bridge (These two trees are, incorrectly hown as Coast Live Oaks on the Tentative Map). The removal of these trees on t 's site is not considered to be a significant impact to the property. . Will there be any significa t impacts to animal life at this site? As a part of the botani sal study which was pe formed, the creek was also investigated for evidence of red-legged.frogs. The creek at this site has had the banks lined N4ith stone wall s and so it can not provide a habitat for the frogs to live in. There may be frogs tha live upstream or downstream of this site and they may travel throug the site but tl ereis no evidence that they live at the project site. Can the loca ion of the h.use site for Lot No. 1 be revised so that it is staggered from the house site shown for Lot No. 2? The applican has revised ,he Tentative Map so that the house site location for Lot No. 1 is not directly in line ith Lot No. 2. FINDINGS Lands of Lindy Properties I,Deer Creek Subdivision June 5,1995 Page 7 The following findings have been madeto support approval of this Tentative Map and proposed subdivision as required in Section 9-1.515 of the Town of Los Altos Hills Municipal Code: 1. The subdivision as proposed would create 3 lots ranging in size from 1.15 acres to 1.34 gross acres,with Lot Unit Factors from 1.061 to 1.089. In this and allother respects, the lots conform! to the Town of.Los Altos Hills Subdivision Ordinance. 2. The proposed subdivision would create lots which would meet the General Plan standards of one acre minimum net lot area for land with an average slope between 0 and 10 percent, and one acre to seven acres for land with an average slope between 10 percent and 50 percent, and in all other respects would be consistent with the General Plan. 3. Access to all three lots, in addition to the property to the south, is proposed off of a new public cul-de-sac off of Purissima Road. Adequate services, including septic, water, fire and police protection, are available to serve the subdivision, as described in the attached information and the Mitigated Negative Declaration for the project. All lots are physically suitable for the proposed development. The Town Geologist has stated concerns that can be addressed through mitigation measures and conditions set forth in the Mitigated Negative Declaration and conditions of approval for the project. It has been determined that each of the newly proposed lots contains a site suitable for building. Therefore,the site is suitable for the proposed density of development. 4. Since all significant environmental effects of the project as identified in the Initial Study for the project have been mitigated as discussed in the Mitigated Negative Declaration, the design of the subdivision and the proposed improvements are not likely to cause substantial environmental damage or substantially and unavoidably injure fish or wildlife or their habitat. 5. All significant environmental effects of the project as identified in the Initial Study for the project have been mitigated as discussed in the Mitigated Negative Declaration, and therefore the design of the subdivision and the proposed improvements are not likely to cause serious public health problems. 6. The City Engineer has reviewed the project and has determined that the design of the subdivision and the improvements will not conflict with easements, acquired by the public at large, for access through or use of, property within the proposed subdivision. Staff is available to answer an questions of the Planning Commission or public. Lands of Lindy Properties I,Dee Creek Subdivision June 5,1995 Page 8 Attachments: Staff Reco mended Conditions of Approval Responses o Mitigated Negative Declaration Draft Mitig tion Monitoring Program Noise Stud by Illingworth&Rod dni Inc. Letter from Mr. &Mrs. Anderson, datied May 21, 1995 Letter from Shannon Paboojian, dated May 31, 1995 Report pre•ared by Barrie D. Coate,dated January 12, 1995 Botanist's R-port by Thomas Reid Associates,dated May 30, 1995 cc: Lindy Pro•erties I Shannon P:boojian 12280 Sara oga-Sunnyvale Road,#101 Saratoga, I alifornia 95070 William H:iss Jennings, I cDermott,Heiss,Inc. 950 South „ascom Avenue,Suite 2111 San Jose,C;lifornia 95128 3 Lands of Lindy Properties I,Deer Creek Subdivision , . . June 5,1995 Page 9 STAFF RECOMMENDED CONDITIONS OF APPROVAL LANDS OF LINDY PROPERTIES I 27591 PURISSIMA ROAD Geotechnical/Earthwork 1. The project geologic consultant shall review and-approve all geotechnical aspects of the subdivision plans to assure that the consultant's recommendations have been properly incorporated as required by the Town Geologist. The results of the plan review shall be summarized in a letter by the project geotechnical engineer and submitted to the City Engineer for review and approval prior to final approval of the subdivision plans. 2. The geotechnical consultant shall inspect, test (as needed), and approve all geotechnical aspects of the project construction. The inspections should include, but not necessarily be limited to: excavations, grading, and trench excavation and compaction. The results of. these inspections shall be described by the geotechnical consultant in a letter and submitted to the City Engineer for review prior to final project approval. 3. Non-engineered fill,shall be removed, or if required to remain in its.current location,shall be recompacted as engineered fill. The actual extent of removal shall be determined in thefield by the Geotechnical Engineer during grading and shall be accomplished to the satisfaction of the City Engineer prior to issuance of building permits. 4. A subdrain shall be constructed in the axis of the swale on Lot 1, the extent of which shall be determined by the project Geotechnical Engineer in the field during grading. The subdrain,.or approved equal, shall be constructed as shown in the Terrasearch Geotechnical Investigation report dated October 28, 1994 (Figure 2, Appendix A) and shall be-accomplished to the satisfaction of the City Engineer prior to issuance of building permits. 5. Proposed residences shall be founded on a pier and grade beam foundation. The bridge structure and site retaining walls shall be founded on either a pier or a spread footing foundation system... Recommendations for both foundation systems are given in the Terrasearch Geotechnical Investigation report dated October 28, 1994. Upon construction-of the foundations for each • lot, the bridgeimprovementsand site retaining walls, conformance with the recommended foundation systems shall be verified to the satisfaction of the Town geologist and City Engineer prior to subsequent inspection approvals. 6. The surface of the areas to be cut and filled at the site shall be stripped cleared and grubbed to remove all existing vegetation and/or other deleterious materials. The actual depth of stripping is unknown and shall be determined in the field by the project Geotechnical Engineer. Stripped material from the Lands of Lindy Properties I,De tr Creek Subdivision June 5,1995 Page 10 site shall not be use as engineered fill but may be stockpiled and used later for landscaping pu •oses. Plans showing the exact areas to be stripped and depth Pf stripping s all be submitted for approval to the City Engineer prior to issuance of gradi g permits. 7. Following site clear ng, the area of non-engineered fill shall be removed to expos native grou d. Keyways shall then be provided at the base of any propoed fill slope .nd shall be a minimum 1E1/2 times machine width, cut into fern native gro P ndandsloped back into the hillside at a gradient of 5%. The fill area shallth:n be constructed by placing engineered fill as specified in mitigation measure• 6, 7, 8, and 9. Benching into the native hillside shall be performed as the Ting progresses. At this time, the construction of a subsurface drain at he back base of the key is not anticipated; however, the final determination shall be made in the field by the project Geotechnical Engineer. This shall be accomplished to the satisfaction of the City Engineer. during grading oper:tions and prior to issuance of building permits. 8. All materials enc•untered on-site, except for debris and organically contaminated. mate ial, are suitable for use as engineered fill. Any large cobbles or boulders hat are encountered shall be broken down to less than 6 inches in size for u•e in the fill. If the existing southern driveway is to be removed, the asphal 'c concrete and aggregate base materials in the existing driveway pavementmay be used for fill provided the asphalt is pulverized and the materials a - properly mixed with the on-site fill. The use of these materials in the upp r.1 foot in landscape areas shall be prohibited. This shall be accomplished to the satisfaction of the project Geotechnical Engineer and City Engineer durin: the grading operations and prior to issuance of building permits. 9. All engineered fill •hall be placed in thin lifts not exceeding 8 inches in uncompacted thick ess and compacted to a minimum of 90% relative compaction at 2% ti 3% above optimum moisture. Relative compaction is based bn the maxi ' urn dry density as determined by ASTM D1557-78 Laboratory Test Pro�edure. This shall be accomplished to the satisfaction of the project Geotech 'cal Engineer and City engineer during the grading operations andpriorto issuance of building permits. 10.. All unsupported cut .nd fill slopes shall not be steeper than 2:1 (horizontal to vertical). Any cut e cavation over 5 feet shall be observed by the project Geotechnical Engine-r-to-detect the presence, or otherwise, of any adverse conditions that may affect stability or retaining wall design. This shall be accomplished to the.•atisfaction of the project Geotechnical Engineer and City Engineer during the grading operations and prior to issuance of building permits. • 11. All fill slopes shall b over-constructed and then cut back to the design slope grade ensuring that all loose material is removed. (Track-walking of slope surfaces does not pro ide adequate soil densities and shall not be utilized as a r Lands of Lindy Properties I,Deer Creek Subdivision .. June 5,1995 Page 11 method of slope compaction.)This shall be accomplished to the satisfaction of the project Geotechnical Engineer and City Engineer during the grading operations and priorto issuance of building permits. 12. Due to the presence.of soils identified as highly and critically expansive, detailed lot-specific construction plans shall be reviewed by the Town Geologist prior to issuance of site development permits and building permits, respectively. . . •- . ' - - - . - . _ . . All geotechnical aspects of detailed construction plans for the proposed bridgeand other subdivision level improvements- shall be reviewed and approved by the project geotechnical consultant for conformance with previously recommended geotechnical design criteria. The results of these evaluations shall be summarized..by the consultant iin a letter and submitted to the.Town for review by the : . - - •: • : = : . : : : . . : - - -- • • . - ' ' • :. City Engineer, prior to issuance of permits for construction,of subdivision level improvements. Land and Easement Dedication 14. A 10 foot wide pathway easement shall be granted to .the public along the northerly property line of the subdivision from Purissima Road to the northeast corner of the property .I- - - - • - - . - - - =- ' - - - Way, to the satisfaction of the City Engineer. The easement to be granted shall be'widened to 30 15 feet at the location from the flowline of Deer Creek extending easterly for a distance of 200 feet to allow for the future installation of switchbacks. The easement shall be kept clear of obstacles,vegetation and obstructions. The dedication shall be accomplished as part of the subdivision Final:Map.; 15. The Final Map shall provide for the requested easements to all utility companies, including but not limited to: Pacific Bell, Pacific Gas & Electric Company and cable television. 16. The subdivision C.C.&R.'s shall be reviewed by the City Attorney for approval ;of the conditions and Irestrictions concerning the restriction of a house design with a maximum of 4 allowable bedrooms as recommended by the County Health.Department for proposed Lot No. ,2 & 3,. and the restrictionof ahouse designs with a maximums-of-six of 6 allowable bedrooms and a maximum floor)area of 6,000 square feet for proposed Lots a '' Lands of Lindy Properties I,Dee Creek Subdivision June 5,1995 Page 12 No. 1 and 2. The .C.&R.'s shall also indicate that fire sprinklers are to be installed in all ne residences for these proposed properties, that the drivev'ay designs f r Lots No. 1 and 2 shall be designed for a fire truck turnaround at eacherminus, and that the foundation design for Lots No. 1 and 2 shall be restricted to type II foundations as defined by the Town's Municipal Code. 17. The a Iplicant shall •e permitted to prepare a bridge construction and right of way improveme is reimbursement agreement for reimbursement from 27575 Puri'ssima Road in the event that said property subdivides. The agree�}l ent shall. be prepared by the applicant and shall be reviewed and approVed by the Cit Attorney. Said agreement will extend for a period not greatex than 10 year . 18.17. The applicant shall •edicate to the Town of Fos Altos Hills a 30 foot half- street applicant right-o;-way along the subdivision frontage of Purissima Road. The d4dication sha 1 be accomplished as part of the Final Map to the satisfaction of the Ci Engineer and shall be accepted at this time. 19. 8. Vehicular access for ots No. 2 and 3 shall berestricted from Purissima Road and shall be accom. ished as part of the Final Map to the satisfaction of the City Engineer. 20.19. The applicant shall .edicate to the Town of Los Altos Hills a 60 foot public right-of-way as sho n on the Tentative Map as Samuel Brubaker Lane. (or a -- - -- - - - 1 • - - e- --- - - The i dedication shall be a i complished as part of the Final Map to the satisfaction of the City Engineer an,, shall be accepted at this time. 21.20. The applicant shall ake an irrevocable offer of dedication to the Town of Los Altos Hills for the .dditional 60 foot public right-of-way connection from Samuel Brubaker L.ne to the property located to the south as indicated on the Tentative Map. e irrevocable offer of dedication shall be accomplished as part of the Final ap to the satisfaction of the City Engineer and shall not be accepted at this f e. - 22.24, - - . : : ' . - - . . . . . - : : - - - . . . ': - . - - .. . _ : the southerly prop rty line as indicated on the Tentaive Map. The . _ _ - - . _ - - ' - - - - - - . The applicant shall be • permitted to retain the existing 20 foot wide access easement along the southe ly property 1'ne. 23.22: The applicant shall :rant public utility easements and public utility access easements to theown of Los Altos Hills where needed within the subdivision for utility construction and maintenance to the satisfaction of the City Engineer. This will provide access for installation and maintenance of 'r Lands of Lindy Properties I,Deer Creek Subdivision June 5,1995 Page 13 the public water system. The dedications shall be accomplished as part of the Final Map to the satisfaction of the City Engineer.. 24.23 A conservation easement shall be granted to the public over Deer Creek,for a 25 foot width from the tops of bank on both sides of .the creek, and to encompass the limits that have been calculatedfor the 100 year flood, to the satisfaction of the City Engineer. The easement to be granted shall also cover the entire portion of Lot No. 2 located between Purissima Road and Samuel Brubaker Lane as indicated on the Tentative Map. The dedication shall be accomplished as part:of the subdivision Final Map. The applicant shall submit a legal desciptionand plat prepared by a registered civil.engineer or a • licensed land surveyor for the easement and the City Attorney shall prepare a grant document that defines the restrictions of the conservation easement as identified by the Planning Commission. The applicant shall have the grant document signed and notarized and shall return it to the Town prior to recordation of the Final Map. Improvements 25.24: A project grading plan which includes an approved,drainage and erosion control plan to minimize the impacts from erosion and sedimentation shall be submitted to and approved by the City Engineer prior to issuance ofgrading permits. This plan shall conform to all standards adopted by the Town of Los Altos Hills andshall comply with all appropriate requirements of the Town's NPDES permit relative to grading and erosion/sediment control including, but not limited to: a) restricting grading during the grading moratorium from November 1 to April 1;b) protecting all finished graded slopes from erosion using such techniques as hillslope benching, erosion control matting, hydroseeding; c) protecting downstream storm- drainage "inlets ' from sedimentation; d) use of silt fencing to retain sediment on the project site; e) any other suitable measures: outlined in the Association of Bay Area Governments (ABAG)Manual of Standards. - 26.25: Construction of proposed pier foundations, spread footings, slabs-on-grade, retaining walls, driveways, septic leach fields,and utility trenches shall occur as recommended in the Terrasea�rch Geotechnical Investigation report dated October 28, 1994or as indicated by the City Engineer. This shall be accomplished to the satisfaction of the Town Geologist and City Engineer prior to further inspection approvals. 27.26: The applicant shall be required to apply for and receive a Creek Alteration Permit from the California State Department of Fish, and Game prior to issuance of grading permits. This shall be accomplished to the satisfaction of the City Engineer. 28.27? The applicant shall be required to apply for and receive a.permit from the Santa Clara Valley Water District!for the bridge improvements or replacement % Lands of Lindy Properties I,D•1r Creek Subdivision v June 5,1995 Page 14 prior to issuance of grading permits. This shall be accomplished to the satisfaction of the C ty. Engineer. 29.E The site drainage associated with the proposed. development must be designed as surfac: flow whenever possible to avoid concentration of the runoff. The applic.nt shall construct drainage improvements within the subdivision bound.ry to the satisfaction of the City Engineer. The proposed :drainaigeshall be o esigned to maintain .the existing flow patterns. The applicant shall veri y that the existing creel has adequate capacity, to the satisfaie tion of the city Engineer. If inadequate, the applicant shall improve the creek to the sati•faction of the City Engineer and to meet all requirements of the Santa Clara alley Water.District. All drainage improvements shall be constructed or bond-d for prior to recordation of the final map. 30a. • - - - : . :• : . _ : :: : - . - - : . -_ . : . "• - . : - providcd by the Santa Clara County Env ironmental Health Services appre Lot No. 1 shall not be permitted to develop a residence with greater than 6 bedrooms, or with greater than 6,000 square feet of floor area if it is required to be served by.a septic santary sewer system. Lot No. 1 shall be'required to install 560 lineal feet of subsurface drainline, shall provide space for an additional 560 lineal feet of subsurface drainline, and shall i 4 stall a 2,000 gallon septic tank. The subdrain for Lot No. 1 shall not divert or discharge drainage in such a manner as to impact leachfileds on this lot or adjoining lots. Thisshall be approved by Santa Clara County Depar#ment of Environmental Health prior to application to the Town for a Site Development Permit.' 30b. . Lot N �. 2 shall not be permitted.to develop'a residence with greater than 4 bedrooms if it is required to be served by a septic sanitary sewer system. Lot Na. 2 shall be required to install 400 lineal feet of subsurface drainline, shall provide space for.an additional 400 lineal feet of subsurface drainline, and shall install a 2 000 gallon septic tank. This shall be approved by Santa Clara County Depa ment of Environmental Health prior to application to the Town for a Site 'evelopment Permit. 30c. Lot No.'3 shall not .e permitted to develop a residence withgreater than 4 bedrooms-if it is re•uired to be served by a septic sanitary sewer system. Lot Na. 3 shall be r:quired to install 600.lineal feet of subsurface drainline, shall provide space or an additional 700 lineal feet of subsurface drainline, and shall install a 2,100 gallon septic tank This shall be approved.by Santa Clara County Depa ment of Environmental Health prior to application to the Town for a Site I evelopment Permit. 31.30: Fire protection impr.vements, including the installation of a fire hydrant on Samuel Brubaker L.ne' : -- - . -- - • : :. : - • = , shall be constructed as requested by Los • ltos Fire Protection District. Improvements shall be 1 Lands of Lindy Properties I,Deer Creek Subdivision June 5,1995 Page 15 constructed and ready.for use prior to the recordation of the Final Map or be bonded for. 32.E The existing bridge over Deer Creek shall be retrofitted or reconstructed to support a fire truck with a weight of 35,000 pounds as requested by Los Altos Fire Protection District. Improvements shall be constructed and ready for use prior to the recordation of the Final Map or be bonded for. 33.32 All,three lots within the subdivision shall be-connected to the public water systemas part of the subdivision improvements. A water main shall be installed to serve the subdivision to the satisfaction of the:City.Engineer and the Purissima Hills Water District prior to the recordation of the Final Map or be bonded for. Any necessary fees shall be paid prior to recordation of the Final Map. 34.33: All utilitieslocated within.the subdivision shall be placed underground, in accordance with Subdivision Ordinance, Sec. 9-1.1105. Cable television, gas, electric, and telephone services, to the property lines are included.in this requirement. Plans for location of all such.utilities are to be included in the improvement plans for the subdivision..: Improvements shall be installed prior to recordation of the Final Map or be bonded for. 35.34: A Type IIB pathway shall be constructed along the westerly property line of the subdivision within the Purissima Road' right of way and shall be constructed cleared as a native pathway within the proposed pathway easement along the northerly property line. A pedestrian bridge shall be constructed at the Deer Creek crossing.to meet the requirements listed in the letter from the Santa Clara Valley Water District to William Heiss dated March 14, 1995..Pathway marker posts shall be installed at the end of the pathway, at.Purissima Road indicating that the pathway does not connect to another pathway.or public. street. . • ' - - - . . . - • . . - . . . - . . . - _ !°.. Improvements shall be:constructed prior to recordation of the Final Map or be bonded for. 3635. The applicant shall design roadway.:improvements for Samuel Brubaker Lane -- - - . . . . • - to the satisfaction of the City Engineer. The terminus of the roadway shall be designed as a turnaround that is adequate for a fire truck, to the satisfaction of the City Engineer and Los Altos Fire Department. Improvements shall be constructed prior to recordation of the Final Map or be bonded for. 37.36 Street Trees shall be required along Samuel Brubaker Lane{-or-street-name-as approved-).and shall also be required,to replace the oak trees that are removed for the construction of the bridge, to the satisfaction of the City Engineer. Trees shall be planted prior to recordation of the Final Map or be bonded for. Planning and Zoning Lands of Lindy Properties I,D••r Creek Subdivision June 5,1995 Page 16 38.3 Any,and all,wells in the property shall be shown on the Improvement Plans, shall be properly r-:•stered with Santa Clara Valley Water District(SCVWD), and shall be either aintained or abandoned in accordance with the SCVWD standards. . 39.38: Pa ment of Park a d'Recreation]fees and all other applicable fees shall be Paymi , Pp required prior to re ordation of the Final Map. 40.39: Fees si all be collec ed in accordance with AB 3158,Chapter 1706, Statutes of 1990, effective Jan ary 1, 1991 requiring that the Department of Fish and 'Game impose an collect filing fees as specified to defray the cost of managing and prot cling fish and wildlife trust resources,if applicable. 41.40; Samuel Brubaker ane : -- - . -- - . I . : : : • : addresses shall be assigned and appr ved by the Town for all three lots as required by the Los Altos Fire Departm nt and in accordance with the Town's policies. 42.44, All subdivision co ditions of approval and si..ibdivision improvements shall be con�tructed and approved by the City Engineer prior to issuance of any site d velopment p rmits. 43.42: The applicant shall inform the Town of any damage and shall repair any damage caused b construction of the subdivision improvements to pathways, private iveways, and public and private roadways prior to final approval of the sub 'vision. 44.43: A grading and co struction operation plan shall be submitted by the subdi'Tider for rev'ew and approval by the City Engineer and Planning Director prior to is uance of grading permit for 'subdivision improvements. The grading/const uction operation plan shall address truck traffic issues regar ing, dust,-no se, and vehicular and pedestrian safety on Purissima Road, lena Road, nd other surrounding rodways; storage of construction materials; placeme t of sanitary facilities; parking for construction vehicles; and parking for con.truction personnel. A dbris box (trash dumpster) shall be placed on site for collection of construction debris. Arrangements must be made with the Los Altos Garbage Company for the debris box, since they have a franchise wi h the Town and no other hauler is allowed within the Town limits. 45.44; Prior to beginning a y grading or construction operations, all significant trees shall be fenced at th- dripline. The fencing shall be of material and structure to clearly delineate ii e dripline. Town staff must inspect the fencing and the trees to be fenced pt for to commencement of grading or construction. The tfence must remain • -place throughout the course of construction.No storage of eq4ment,vehicles or debris shall be allowed within the driplines of these trees. Lands of Lindy Properties I,Deer Creek Subdivision June 5,1995 Page 17 • 46. Upon discovering or unearthing any possible burial site as evidenced by human skeletal remains or artifacts, the person making such discovery shall immediately notify the County of Santa Clara Coroner and no further disturbance of the site may be made except as authorized by the County Coordinator of Indian Affairs. This shall be accomplished to the satisfaction of the County Coroner's Office and the Planning Director, as may be necessary during the construction of the subdivision improvements. 47. All recommendations of the project botanist and project arborist shall be required to be followed during the construction of the subdivision improvements and shall be accomplished to the satisfaction of the Town Planning Director. FEES Storm Drainage (To be determined) Street Improvement (To be determined) Path Improvement (To be determined) Parks and Recreation (To be determined) Dept. of Fish and Game $1275.00 TOTAL RESPONSES TO MI TIGATED NEGATIVE DECLARATION DE tR CREEK SUBDIVISION Studies or reports utilized in .nalyzing this project to provide support for comments include the follo%Ying that wer not available at the time of preparation of the mitigated negative declaration: • Drainage Evaluation;Je 'ngs,McDermott,Heiss,Inc.,May 9, 1995 • Sanitary Sewer Septic S stem Evaluation, County of Santa Clara Department of Environmental Health, ay 5, 1995 • Botanical tudy,,Thoma• Reid Associates,May 1995 These reports are on file at Town Hall and may be viewed during normal business hours (8-12 and:115 Monday-Fr day). III. Water The absorption rates ar: anticipated to decrease resulting in an increase in the rate and amount of sur .ce runoff due to the proposed project. The absorption rates may be mitigated •uring the landscaping rediew anticipated to be required with the individual site m evelopment permits. Declining absorption rates and an increase in surface runo;f may be mitigated by requiring additional plantings at that time. While the Improvement of the proposed project site is anticipated to result in discharges into surface aters, the surface water quality is not anticipated to be altered to any significa ce. The conservation easement that is proposed for the Deer Creel corridor is i tended to provide the natural landscape buffer between the proposed developm-nt and the creek that is recommended by SCVWD for water quallity preservat on. The existing soil conditions at the project site currently provide a cl.y layer over a layer of sandy, gravelly soil. These conditions will help to prevent surface water from entering the leach field drainlines and will als I help to prevent the effluents which are flowing into the leach fields from res rfacing and flowing to the creek as surface sheetflow. It will be important d ring the construction of the leach fields to maintain these soil conditions s• that the leach fields will operate properly. The construction of the leac fields shall be observed by the project geotechnical consultant as specified i Mitigation Measure 11. Santa Clara Valley Wat r District (SCVWD) reviewed the proposed tentative map for this project in J.nuary 1995,and concluded as follows: "Based on information •rovided and an estimated 1% [100 year] flow rate of 383 cubic feet per seco d, the site would be subject to minor flooding. The Deer Creek Subdivision Responses to Mitigated Negative Declaration flooding would generally extend.about 25 feet from the existing top of bank. The [SantaClara Valley Water] District recommends that this flooding area be protected and no structures or fill be allowed,within this area." Based on this study by SCVWD and the standard Town policy regarding conservation of creeks, a conservation easement has been required to be placed over Deer Creek,extending 25 feet from each existing top of bank. While no groundwaters are anticipated to be:affected by development of the proposed project, either through: alteration of flow or a change in thequantity, there has been some question as to whether historically, evidence indicates the possibility of a spring on the site. The geotechnical investigation performed by Terrasearch did not encounter any evidence of a spring on this site. Drainage in the vicinity of the proposed Lot No. 1 has also been evaluated by the project engineer and addresses the drainage swale that enters the property from the northeasterly direction and flows to Deer.Creek. The evaluation from Jennings,McDermott,Heiss,Inc., dated May.9,1995,concluded as follows: "Where the swale enters the property, no 'grading or improvements are comtemplated. This is the case for the next hundred feet or so. It is required by, the soil engineer to construct a subdrain across the axis of this drainage swale to intersect any subsurface seepage water that may be following the swale alignment [see Proposed Mitigation Measure No. 2]. As the swale continues Westerly, it will be intercepted by the proposed driveway to [proposed] Lot 2. The swale will be regraded to follow the edge of the driveway in a similar configuration as it exists today. By the time the swale reaches [proposed] Lot 1, it has transitioned into more or less sheet flow and proceeds to cross [proposed] Lot 1 as sheet flow to Deer Creek. This condition will remain since no structural improvements are comtemplated within the sheet flow region of [proposed] Lot 3. There will be drain fields in the area of [proposed] Lot 3 which would be unaffected .by the sheet flow over the surface." IV. Plant Life A tree survey report prepared by arborist Barrie D. Coate catalogued a total of 72 trees on-site. Of this total, eight tree are proposed by the.arborists for removal due to death, poor health/structur , or damage/infringement on an adjacent tree. Seven-additional trees are proposed by the proponent to be removed as necessary for construction of on-site roadways. This includes two coast live oak trees. Due to the number of trees remaining on-site,removal of the recommended trees is not anticipated to result in a significant impact. It is anticipated that landscaping will be required on the individual lots when they apply for development through the Town. While landscapingfor the 2 , Deer Creek Subdivision " Responses to Mitigated Negative Declaration individual lots may i troduce new species to this site, the Town encourages the planting of speci:s that are native to this area and so the change in the diversity of species, o numbers of any species of plants, is not anticipated to be signi cant. The la dscaping is also not be anticipated to be a significant introduction of new pecies nor is itanticipated to create a barrier to the normal replenishment of existing species. A botanical study w.s performed by Taylor Peterson with Thomas Reid Associates in respon,e to the Planning Commission and public's concerns about plant life at this project site. The site was foundto be highly disturbed already and there are of any rare plant species or habitats at this site. There were only:common p1.nts found at the site. There is a riparian habitat through Deer Creek that has been dominated by Coast Redwoods that were planted. The creel bed is domi ated by Vinca, a non-native invasive plant. The rest of the site iscovered in non-native annual grassland that is. interspersed with native and ornamental trees. The only trees that are anticipated to be affected by this stbdivision is 0 ne Coast Live Oak that will be affected by the proposed leachfield for Lot 2 an. two Coast Redwoods that will need to be removed for the construction of the bridge. V. Animal Life - Due to the size of the d-velopment proposed, it is not anticipated to significantly impact existing species. A study was performed at this site to determine if it was a habitat'for red-1•gged frogs. The stone walls that have been placed in the creek bank may trap the frogs but would not provide a habitat for them to live in. The frogs ma live upstream or downstream from this site and may travel through this sit: but there is no evidence that they live at this site. No other sigrificant wildli e habitat areas or rare or endangered species are known to exist on-site. The'co ervation easement proposed for the Deer Creek corridor will prevent urban us:s and development-related activities from encroaching upon this area. It is a ticipated that domestic animals may be introduced into the area upon develop ent,but not in significant numbers. VI. Noise A Noise Assessment w.s-prepared by Illingworth&Rodkin,Inc. in May of 1992. That report concluded .s follows: "The existing noise lev:ls range from-a 24-hour average day/night level (Ldn)of 52 to 60 dBA. Noise lev-is are not anticipated to increase in the future along this stretch of I-280. Whil: the Town of Los Altos Hills does not have specific guidelines related to ou door noise exposure,their standards indicate that an Lam, of 60 dl3/ or less is co patible with residential development. This is typical of most municipalities i Northern California. The site's noise exposure is, 3 Deer Creek Subdivision Responses to Mitigated Negative Declaration therefore, acceptable for residential development without additional mitigation. The Town does;require that.interior noise levels not exceed an Ldn of 45 dBA. Typical California residential construction provides 15 dBA of noise reduction with open windows when going from outside to inside, and 20-25 dBA of noise reduction with,the windows closed. Interior noise levels would also be in. compliance without additional mitigation." There may be noise impacts to existin g residents as a result of people-generated noise on the site, but the impacts are not anticipated to be significant. Off-site traffic noise increases are anticipated be negligible, as well. There would be short-term increases in the noise environment in the area during construction. Compliance with the Town policies and limiting construction to weekday, daytime hours,_would mitigate construction noise impacts to a less than significant level. VII. Light and Glare While the devlopment of this property will generate additional light from this site, significant levels of light or glare in excess of those provided for in the Town Zoning Ordinance are not anticipated to-result. XVI. Utilities and Service Systems Sanitary sewer service is currently not available to this area which results in septic tanks and leachfields being the only available sanitary sewerage disposal. The acceptability of the proposed septic leachfield sites have been conditioned by the County of Santa Clara Department of Environmental Health in their letter dated May 5,1995,and are listed in Mitigation Measures No. 16-18. XX. Cultural Resources While there is no knowledge of a prehistoric or historic archaeological site on this property and the project is not anticipated to cause a physical change which would affect unique cultural values, Mitigation Measure 20 addresses the discovery of cultural resources on the project site. •4 s • Deer Creek Subdivision Responses to Mitigated Negative Declaration REVISE 0 MITIGATION MEASURES 1. Non-engineered fill sh.ll be removed, or if required to remain in its current location, shall be reco •acted as engineered fill. The actual extent of removal shall be determined in e field by the Geotechnical Engineer during grading and shall be accomplished t• the satisfaction of the City Engineer prior to issuance of building permits. 2. A subdrain shall be co -tructed in the axis of the swale on Lot 1, the extent of which shall be determi ed by the project Geotechnical Engineer in the field during grading. The sub•rain, or approved equal;shall be constructed as shown in the Terrasearch Geo echnical Investigation report dated October 28, 1994 (Figure 2, Appendix A) nd shall be accomplished to the satisfaction of the City Engineer prior to issuan•e of building permits. 3. Proposed residences sha 1 be founded on a pier and grade beam foundation. The bridge structure and situ retaining walls shall be founded on either a pier or a spread footing founda ion system. Recommendations for both foundation systems are given in th- Terrasearch Geotechnical Investigation report dated October 28, 1994. Upon onstruction of the foundations for each lot, the bridge improvements and site retaining walls, conformance with the recommended foundation systems shall be verified to the satisfaction of the Town geologist and City Engineer prior to su•sequent inspection approvals: 4. The surface of the areas to be cut and filled at the site shall be stripped cleared and .grubbed to remo e all existing vegetation and/or other deleterious materials. he actual de•th of stripping is unknown and shall be determined in the field b�y the project f eotechnical Engineer. Stripped material from the site shall not be used as en:,ineered fill but may be stockpiled and used later for landscaping purposes. P showing the exact areas to be stripped and depth of stripping sliall be submi ed for approval to the City Engineer prior to issuance of grading pe1mits.. 5. Following site clearing, the area of non-engineered fill shall be removed to expose native ground. eyways shall then be provided at the base of any proposed fill slope and s all be a minimum 1-1/2 times machine width, cut into firm native ground and -loped back into the hillside at a gradient of 5%. The fill area shall then be const cted by placing engineered fill as specified in mitigation measures 6J17, 8, and 9. B nching into the native hillside shall be performed as the filling progresses. At this time, the construction of a subsurface drain at the back base of the key is not anticipated;however, the final determination shall be made in the field by the projec Geotechnical Engineer. This shall be accomplished to the satisfaction of the ity Engineer during grading operations and prior to issuance of building perrn4its. 5 } Deer Creek Subdivision Responses to Mitigated Negative Declaration 6. All materials encountered on-site,except for debris and organically contaminated material, are suitable for use as engineered fill. Any large cobbles or boulders that are encountered shall be broken down to less than 6 inches in size for use in the fill. If the existing southern driveiway is to be removed, the asphaltic concrete and aggregate base materials in the existing driveway pavement may be used for fill provided the asphalt is pulverized and;the materials are properly mixed with the on-site fill: The use of.these'materials in the upper 1 foot in landscape areas shall be prohibited. This shall be accomplished to the satisfaction of the project Geotechnical Engineer and City Engineer during the grading operations and prior to issuance of building permits. 7. All engineered fill shall be placed in thin lifts not exceeding 8. inches.,in uncompacted thickness and compacted to a minimum of 90% relative compaction at 2% to 3% above optimum moisture. Relative compaction.is based on the maximum dry density as determined by ASTM D1557-78 Laboratory Test Procedure. This shall be- accomplished to the satisfaction.. of the project Geotechnical Engineer and City Engineer during,the grading operations and prior to issuance of building permits. 8. All unsupported cut and fill slopes shall not be steeper than.2:1 (horizontal to vertical). Any cut excavation over 5 feet shall be observed by the project Geotechnical Engineer to detect the presence, or otherwise, of any adverse conditions that may affect stability or retaining wall design. This shall be accomplished to the satisfaction of the project Geotechnical Engineer and City Engineer during the grading operations and prior _to issuance of building permits. 9. All fill slopes shall be over-constructed and then cut back to the design slope grade ensuring that all loose material is removed. (Track-walking of slope surfaces does not provide adequate soil densities and shall not be utilized as a method of slope compaction.) This shall be accomplished to the satisfaction of the project Geotechnical Engineer and City Engineer during the grading operations and prior to issuance of building permits. • _10. A project grading plan which includes an approved drainage and erosion control plan to minimize the impacts from erosion and sedimentation shall be submitted to and approved by the City Engineer prior to issuance of grading permits. This plan shall conform to all standards adopted by.the Town of Los Altos Hills and shall comply with all appropriate requirements of the,Town's NPDES permit relative to grading and erosion/sediment control including,but not limited to: a) restricting grading during the grading moratorium from November 1 to April 1; b) protecting all.finished graded slopesfrom erosion using such techniques as hillslope benching, erosion control matting, hydroseeding; c) protecting downstream storm drainage inlets from sedimentation; d).use of silt fencing to 6 � r Deer Creek Subdivision Responses to Mitigated Negative Declaration retain se ment on the project site;e) any other suitable measures outlined in the Association of Bay Area Governments (ABAG)Manual of Standards.. 11. Construction of proposed pier foundations, spread footings,.slabs-on-grade, retaining isalls,driveways, septic leach fields,and utility trenches shall occur as recommended in the Terrasearch Geotechnical Investigation report dated October 28, 1994 or as indicated by the City Engineer. This shall be accomplished to the satisfaction of the Town Geologist and City Engineer prior to further inspection approvals: 12. Due to th- presence of soils identified as highly a d critically expansive, detailed lot-specifi construction plans shall be reviewed y the Town Geologist prior to issuance .f site development permits and building permits,respectively. . of existing fill materials in this arca shallbe assessed. The consultant shall comment�on the acceptability of all proposed septic lcachfield sites from a - -- - - - -- -• • -. All geotechnical aspects of detailed construction plans for he proposed bridge and other subdivision level improvements shall be revie'ed and approved by the project geotechnical consultant for conformance with previously recommended geotechnical design criteria. The results of hese evaluations shall be summarized by the consultant in a letter and submitted to the Town for review by the _ . - _ _ . . . . • - - - . ' . =. City Engineer, prior to issuance of permits for construction of subdivisi en level improvements. 14. The appli ant shall be required to apply for and receive a Creek Alteration Permit fro the California State Department of Fish and Game prior to issuance of gradin permits. This shall be accomplished to the satisfaction of the City Engineer. 15. The site drainage associated with the proposed development must be designed as surfac l flow whenever possible to avoid concentration of the runoff. The proposed drainage shall be designed to maintain the existing flow patterns and shall be designed to the satisfaction of the City Engineer prior to issuance of grading permits. Final storm drainage improvements shall be inspected by the City Engineer and,any and all deficiencies corrected to his satisfaction prior to acceptance of subdivision improvements. 16. Lot No. 1 shall not be permitted to develop a residence with greater than 6 bedrooms,or with greater than 6,000 squarefeet of floor area if it is required to be served by a septic sanitary sewer system. clot No. .1 shall be required to 7 Deer Creek Subdivision Responses to Mitigated Negative Declaration install 560 lineal feet of subsurface drainline, shall provide space for an additional 560linealfeet of subsurface drainline, and shall install a 2,000 gallon septic tank. The subdrain for Lot No. 1 shall not divert or discharge drainage in such a manner as to impact leachfields on this lot or adjoining lots. This shall be approved by Santa Clara County Department of Environmental: Health prior to application to the Town for a Site Development Permit. 17. Lot No..2 shall not be permitted to develop a residence with greater than 4 bedrooms if it is required to be served by a septic sanitarysewer:system. Lot No. 2 shall be required to install 400 lineal feet of subsurface drainline, shall provide space for an additional 400 lineal feet of subsurface drainline, and shall install a 2,000 gallon septic tank. This shall be approved by Santa Clara County Department of Environmental Health prior to application to.the Town for a Site Development Permit. 18. Lot No.,3.shall not be permitted to develop a residence with greater than 4 bedrooms if it is required to be served by a•septicsanitary sewer system. Lot No. 3 shall be required to install 600; lineal feet of subsurface drainline, shall provide space for an additional 700 lineal feet of subsurface drainline, and shall install a 2,000 gallon septic tank. This shall be approved by Santa Clara County Department of Environmental Health prior to application to the Town for a Site Development Permit. 19. Upon discovering or unearthing any possible burial site as evidenced by human skeletal remains or artifacts,i the person making such discovery shall immediately notify the County of Santa Clara Coroner and no further disturbance of the site may be made except as authorized by the County Coordinator of Indian Affairs. This shall be accomplished to the satisfaction of the County Coroner's Office and the Town Planning Director, as may be necessary during the construction of the subdivision improvements. • 8 DRAFT EER CREEK SUBDIVISION MITIG TION MONITORING PROGRAM 1.0 AUTHORITY Pursuant to California Re•ources Code, Section 21081.6 (AB 3180), the Town of Los Altos Hills has prepar•d a mitigation monitoring program for the proposed Deer Creek piroject as set forth in the approved permit conditions. 2.0 PURPpSE ' • The purpose of the mitiga ion monitoring program is to ensure compliance with and effectiveness of the itigation measures set 'forth in the Initial Study and Negative Declaration (IS/ •) prepared for the Deer Creek Subdivision project. CEQA requires monitoriny of mitigation measures for those impacts identified in the IS/ND as being signifi sant or potentially significant. 3.0 ADM INISTRATIO AND MANAGEMENT The Town's mitigation onitoring program for the Deer Creek Subdivision project consists of two major elements: 'A. A list of mit gation conditions and verifications required of the roject spo sor at each stage of the project approval . and - development. A checklist to document and verify mitigation condition compliance. The administJation and m. agement of the mitt ation monitoring program shall be the responsibility of th& Town. The project applicant shall fund the costs for monitoring in accord with he terms of the Town of Los Altos Hills fee schedule. The responsibility of the T.wn throughout the monitoring effort includes serving as a liaison between the v.rious Town Departments, the project applicant, and the applicants contractors, :nd maintaining prompt and regular communications with on-site 'environment;1 monitors and specialists, and project applicant's contractors re ponsible for performance and permit compliance. 4.0 PROJECT SPONSOI 'S RESPONSIBILITY The project applicant shall perform the measures required of them and comply with the verilfication and eporting requirements identified in this Plan as a condition of approval of he project. The project applicant understands and agrees that activities for a :iven phase shall not commence until the Town has 1 • approved the applicant's mitigation plan for that phase. The project sponsor's • responsibilities include administering and preparing daily logs, status reports, compliance reports, and the final construction monitoring report;monitoring on- site, day-to-dayy construction activities, including the direction of environmental monitors and' environmentalspecialists in the understanding of all permit conditions, site-specific project requirements, construction schedules and environmental quality control efforts; ensuring contractor knowledge of and compliance with all appropriate permit conditions; reviewing all construction impact mitigations and, if need be, propose improvements to the Town; and requiring correction of observed activities that violate project environmental conditions,or that represent unsafe or dangerous conditions. The project sponsor shall submit a detailed written plan for mitigation compliance to be reviewed and approved by the Town of Los Altos Hills Planning Director at each phase of project development. The compliance plan will serve a dual purpose of verifying cpmpliance with the mitigation measures for the proposed project and of generating information on the effectiveness of the mitigation measures. This plan shall describe the steps the project sponsor (and project contractor) will take to assure compliance with project conditions and shall include a checklist verifying compliance with permit conditions. The plan shall also include provisions for any mitigation monitoring personnel found necessary to implement the plan. The monitoring personnel will be retained by the project sponsor and will have expertise in appropriate disciplines. Town staff and/or hired consultants under contract to the Town will verify mitigation compliance by means of the checklist. The project applicant shall agree,to fund any additional Town costs for monitoring staff or verification by registered professionals. 5.0 COMMUNICATION AND REPORTING REQUIREMENTS Prior to any construction activities, meetings shall be convened involving Town staff, the project sponsor and general contractors to review the mitigation monitoring program, to identify responsibilities and authority of participants, to define what criteria will be used to gauge permit compliance, and to identify under what conditions the Town will halt activities and require remedial or corrective measures. The plan shall formulate an effective reporting system which documents on-site monitoring activities and compliance with conditions. The plan shall include submission of annual reports to the Planning Director describing the project status and a checklist verifying compliance with permit conditions. Annual reports shall be submitted for each year up until one year after occupancy. 2 Mitigation Monitoring Checklist Deer Creek Subdivision Mitigation Measure Implementing Action Approval By Sign-Off/Date - + 1. Non-engineered fill shall be removed,or if Determination of extent of removal to required to remain in its current location, be made in the field during grading, Geotechnical Engineer Name shall be recompacted as engineered fill. prior to issuance of building permits. The actual extent of removal shall be determined in the field by the Date Geotechnical Engineer during grading and shall be accomplished to the satisfaction of City Engineer the City Engineer prior to issuance of Name building permits. Date 2. A subdrain shall be constructed in the axis Determination to be made in the field Geotechnical Engineer of the swale on Lot 1, the extent of which during grading, prior to issuance of Name shall be_-determined_b_y__ the project building permits. Geotechnical Engineer in the field during grading.The subdrain,or approved equal, Date shall be constructed as shown in the Terrasearch Geotechnical Investigation report dated October 28, 1994 (Figure 2, City Engineer Appendix A)and shall be accomplished to Name the satisfaction of the City Engineer prior to issuance of building permits. Date Mitigation Monitoring Checklist Deer Creek Subdivision Mitigation Measure Implementing Action Approval By Sign-Off/Date 3. Proposed residences shall be founded on a Upon construction of each lot, the Town Geologist pier and grade beam foundation. The bridge improvements and site Name bridge structure and site retaining walls retaining walls, prior to subsequent shall be founded on either a pier or a inspection approvals. spread footing foundation system. Date Recommendations for both foundation systems are given in the Terrasearch Geotechnical Investigation report dated October 28,1994.Upon construction of the City Engineer foundations for each lot, the bridge Name improvements and site retaining walls, conformance with the recommended foundation systems shall be verified to the Date satisfaction of the Town geologist and City Engineer prior to subsequent inspection. approvals. 4. The surface of the areas to be cut and filled Determination of stripping shall be City Engineer at the site shall be stripped cleared and made in the field. Plans to be Name grubbedtoremove-all-existing vegetation submitted—for approval prior to and/or other deleterious materials. The issuance of grading permits. actual depth of stripping is unknown and Date shall be determined in the field by the project Geotechnical Engineer. Stripped material from the site shall not be used as engineered fill but may be stockpiled and used later for landscaping purposes.Plans showing the exact areas to be stripped and depth of stripping shall be submitted for approval to the City Engineer prior to issuance of grading permits. Mitigation Monitoring Checklist Deer Creek Subdivision Mitigation Measure Implementing Action Approval By Sign-Off/Date 5. Following site clearing; the area of non- Determination for subsurface drain at Geotechnical Engineer engineered fill shall be removed to expose the backbase of the key to be made in Name native ground. Keyways shall then be the field, during grading operations provided at the base of any proposed fill and prior to issuance of building slope and shall be a minimum 1-1/2 times permits. Date machine width, cut into firm native ground and sloped back into the hillside at a gradient of 5%.The fill area shall then be City Engineer Name constructed by placing engineered fill as specified in mitigation measures 6, 7, 8, and 9. Benching into the native hillside Date shall be performed as the filling progresses. At this time, the construction. of a subsurface drain at the back base of the key is not anticipated; however, the final determination shall be made in the field by the project Geotechnical Engineer.; This shall be accomplished to the satisfaction of the City Engineer during grading.operations and prior to issuance of building permits. _ Mitigation Monitoring Checklist Deer Creek Subdivision Mitigation Measure Implementing Action Approval By Sign-Off/Date 6. All materials encountered on-site, except During grading operations and prior Geotechnical Engineer for debris and organically contaminated to issuance of building permits. Name material,are suitable for use as engineered fill..Any-large cobbles or boulders that are encountered shall be broken down to less Date than 6 inches in size for use in the fill. If the existing southern driveway is to be removed, the asphaltic concrete and CityEngineer aggregate base materials in the existing Name driveway v m may be used-for fill provided the asphalt is pulverized and the Date materials are properly mixed with the on- site fill. The use of these materials in the upper 1 foot in landscape areas shall be prohibited. This shall be accomplished to the satisfaction of the project Geotechnical Engineer and City Engineer during the grading operations and prior to issuance of building permits. 7. All engineered fill shall be placed in thin During grading operations and prior Geotechnical Engineer lifts not exceeding 8 inches in to issuance of building permits. Name uncompacted thickness and compacted to a minimum of 90% relative compaction at 2% to 3% above optimum moisture. Date Relative compaction is based on the maximum dry density as determined by ASTM D1557-78 Laboratory Test City Engineer Name Procedure. This shall be accomplished to the satisfaction of the project Geotechnical Engineer and City Engineer during the Date grading operations and prior to issuance of building permits. Mitigation Monitoring Checklist Deer Creek Subdivision • Mitigation Measure Implementing Action Approval By Sign-Off/Date 8. All unsupported cut and fill slopes shall During grading operations and prior Geotechnical Engineer not be steeper than 2:1 (horizontal to to issuance of building permits. Name vertical). Any cut excavation over 5 feet shall be observed by the project Geotechnical Engineer to detect the Date presence, or otherwise, of any adverse conditions that may affect stability or retaining wall design. This shall be City Engineer Name accomplished to the satisfaction of the project Geotechnical Engineer and City Engineer during the grading.operations Date and prior to issuance of building permits. 9.___All_fill_slopes-shall_be_.overconstructed During grading operations and prior Geotechnical Engineer and then cut back to the design slope to issuance of building permits. Name grade ensuring that all loose material is removed.(Track-walking of slope surfaces does not provide-adequate soil densities Date and shall not be utilized as a method of slope compaction.) This shall be accomplished to the satisfaction of the City Engineer Name project Geotechnical Engineer and City .. Engineer during the grading operations and prior to issuance of building permits. Date Mitigation Monitoring Checklist Deer Creek Subdivision Mitigation Measure Implementing Action Approval By Sign-Off/Date 10. A project grading plan which includes an Prior to issuance of grading permits. City Engineer approved drainage and erosion control plan-tom;nimize_theimpactsJrom_erosion _Name and sedimentation shall be submitted to and approved by the City Engineer prior to issuance of grading permits. This plan Date shall conform to all standards adopted by the Town of Los Altos Hills and shall comply with all appropriate requirements of the Town's NPDES permit relative to grading and erosion/sediment•control including,but not limited to:a)restricting grading during the grading moratorium from November 1 to April 1;b)protecting all finished graded slopes from erosion using such techniques as hillslope benching, erosion control matting, hydroseeding; c) protecting downstream storm drainage inlets from sedimentation; d)use of silt fencing to retain sediment on the project site; e) any other suitable measures outlined in the Association of Bay Area Governments(ABAG)Manual of Standards. Mitigation Monitoring Checklist .. Deer Creek Subdivision Mitigation Measure Implementing Action Approval By Sign-Off/Date 11. Construction of proposed pier Prior to further inspection approvals. Geotechnical Engineer foundations, spread footings, slabs-on- Name grade, retaining walls, driveways, septic leach fields, and utility trenches shall occur as recommended in the Terrasearch Date Geotechnical Investigation report dated October 28, 1994 or as indicated by the _ _ City Engineer. This shall be accomplished City Engineer Name to the satisfaction of the Town Geologist and City Engineer prior to further inspection approvals. Date 12. Due to the presence of soils identified as Prior to issuance of site development Town Geologist - highly and critically-expansive,--detailed --permits-and-building-permits.- - -Name -lot-specific.construction plans shall be reviewed by the Town Geologist prior to issuance of site development permits and Date building permits,respectively. 13. All geotechnical aspects of detailed Prior to issuance of permits for City Engineer construction plans for the proposed bridge construction of subdivision level Name and other subdivision level improvments improvements shall be reviewed and approved by the project geotechnical consultant for Date conformance with previously recommended geotechnical design criteria. The results of these evaluations shall be summarized by the consultant in a letter and submitted to the Town for review by the City Engineer, prior to issuance of permits for construction of subdivision level improvements. Mitigation Monitoring Checklist Deer Creek Subdivision Mitigation Measure Implementing Action Approval By Sign-Off/Date 14. The applicant shall be required to apply Prior to issuance of grading permits City Engineer for and receive a Creek Alteration Permit Name from the California State Department of Fish and Game prior to issuance of grading permits. This shall be Date accomplished to the satisfaction of the City Engineer. 15. The site drainage associated with the Drainage plans to be submitted prior City Engineer proposed development must be designed to issuance of grading permits. Name as surface flow whenever possible to avoid concentration of the runoff.The proposed Final storm drainage drainage shall be designed to maintain the improvements/deficiencies corrected Date existing flow patterns and shall be prior to acceptance of subdivision designed to the satisfaction of the City improvements. Engineer prior to issuance of grading permits. Final storm drainage City Engineer improvements shall be inspected by the Name City Engineer and any and all deficiencies corrected--to--his–satisfaction–prior-—to — acceptance of subdivision improvements. . Date Mitigation Monitoring Checklist Deer Creek Subdivision Mitigation Measure Implementing Action Approval By Sign-Off/Date 16. Lot No.1 shall not be permitted to develop Prior to application for Site Santa Clara County a residence with greater than 6 bedrooms, Development Permit. Department o f Name or with greater than 6,000 square feet of Environmental Health floor area if it is required to,be served by a septic sanitary sewer system. Lot No. 1 Date shall be required to install 560 lineal feet of subsurface drainline, shall provide space for an additional 560 lineal feet of subsurface drainline, and shall install a _ 2,000 gallon septic tank. The subdrain for Lot No. 1,shall not divert or. discharge drainage in such a manner as,to impact leachfields on this lot or adjoining lots. This shall be approved by SantaClara _County Department of Environmental Health prior to application to the Town for - -- - a Site Development Permit. 17. Lot No.2 shall not be permitted to develop Prior to application for Site Santa Clara County a residence with greater than 4 bedrooms, Development Permit. Department o f Name if it is required to be served by a septic Environmental Health sanitary sewer system. Lot No. 2 shall be required to install 400 lineal feet. of Date subsurface drainline, shall provide space for an additional 400 lineal feet of subsurface drainline, and shall install a 2,000 gallon septic tank. This shall be approved by Santa Clara County Department of Environmental Health prior to application to the Town for a Site Development Permit. Mitigation Monitoring Checklist Deer Creek Subdivision Mitigation Measure Implementing Action Approval By Sign-Off/Date 18. Lot No.3 shall not be permitted to develop Prior to application for Site Santa Clara County a residence with greater than 4 bedrooms Development Permit. Department o f Name if it is required to be served by a septic Environmental Health sanitary sewer system. Lot No. 3 shall be required to install 600 lineal feet of Date subsurface drainline, shall provide space for an additional 700 lineal feet of subsurface drainline, and shall install a 2,000.gallon septic tank.. This shall be approved by Santa Clara County Department of Environmental Health prior to application to the Town for a Site Development Permit. 19. Upon discovering or unearthing any As may be necessary during County Coroner's Office possible burial site as evidenced by human construction of the subdivision Name skeletal remains or artifacts, the person improvements. making such discovery shall immediately notify the County of Santa Clara Coroner Date and-no-further disturbance-of-the-site-may- be isturbance-of-the-site-maybe made except as authorized by the County Coordinator of Indian Affairs.This shall be accomplished to the satisfaction of Planning Director Name the County Coroner's Office and the Town Planning Director as may be necessary during the construction of the subdivision Date improvements. ILIIlYG11VORTH&RODK1N,INC. ACOUST l CAL ENGI NEERSIIIII May 28, 1992 la Richard Childress Debcor Corporation 21625 Stevens Creek Boulevard Cupertino, CA 95014 SUBJECT: Lindy Properties Los Altos Hills Four-Acre Subdivision -- Noise Assessment Summary Dear Dick: We have completed our noise monitoring survey at the site. The existing noise levels range from a 24-hour average day/night level (Ldn) of 52 to 60 dBA. Noise levels are not anticipated to increase in the future along this stretch of I-280. While the Town of Los Altos Hills does not have specific guidelines related to outdoor noise exposure, their standards indicate that an Ldn of 60 dBA or less is compatible with residential development. This is typical of most municipalities in Northern California. The site's noise exposure is, therefore, acceptable for residential development without additional mitigation. The Town does require that interior noise levels not exceed an Ldn of 45 dBA. Typical California residential construction provides 15 dBA of noise reduction with open windows when going from outside to inside, and 20 to 25 dBA of noise reduction with the windows closed. Interior noise levels would also be in compliance without additional mitigation. There will be no significant noise impacts to existing residents as a result of people-generated noise on the site. Offsite traffic noise increases would be negligible, as well. There would be short-term increases in the noise environment in the area during construction. Compliance with the Town policies and limiting construction to weekday, daytime hours, would mitigate construction noiselimpacts to a less than significant level. We should complete our report today and will be sending it to you by overnight mail. If you have any questions after receipt of the report, please do not hesitate to call. Sincerely yours, Richard B. Rodkin, PE RBR:gfl 85 Bolinas Road, #11 • Fairfax, California 9493110 • (415) 459-5507 • FAX (415) 459-6448 ENVIRONMENTAL NOISE SSESSMENT LINDY PROPERTIES PROP SED FOUR-ACRE SUBDIVISION, LOS ALTOS HILLS, CALIFdRNIA May 29, 1992 Prepared for: Lindy Properties c/o Debcor Corporation 21625 Stevens Creek Boulevar' Cupertino, CA 95014 Prepared by: Richard B. Rodkin,' PE Illingworth & Rodkin, Inc._ 85 Bolinas Road, Suite 11 Fairfax, CA 94930 • (415) 459-5507 ,,. Job No.: INTRODUCTION/SUMMARY This report assesses the acoustical issues related to the proposed residential development of a four-acre parcel on Purissima Road just south of Elena Road in Los Altos Hills, California. The project location is shown on Figure 1. Technical terms used in the report are defined in Table'1. Interstate 280 is the only significant noise source affecting the site. The most significant issue is the compatibility of the noise environment at the site with the proposed residential development. The potential noise impacts to eisting residents in the area from the proposed development of the site are also analyzed. In summary, the noise environment at the site s currently and in the future will continue to be compatible with residential development. The site is partially acoustically shielded from Interstate 280 noise by intervening topography. The residential,use is consistent with existing development in the area and will not change either the character of the noise environment or the noise levels at existing residences. Project-generated,traffic would not noticeably or measurably,affect the noise environment. In summary, the proposed project would result in no significant noise impacts. . I NOISE CRITERIA The following policies from the Town of Los Altos Hills' Noise Element of the General Plan are relevant to this project: Residential Land Use • All land development adjacent to Interstate 280 or Foothill Expressway should be i designed so asto minimize the social psychological, physiological, and economic impact of noise generated by traffic movement and land developers should make sure to provide for noise attenuation. - • • Interior community noise equivalent levels (CNEL or Lam) attributable to exterior sources shall not exceed 45 dBA in any habitable room. (1) 1 TABLE 1 DEFINITIONS OF ACOUSTICAL TERMS 1 TERM DEFINITIONS Decibel, dB A unit describing the amplitude of sound, equal to 20 times the logarithm to the base 10 of the ratio of the pressure of the sound pressure, which is 20 miciopascals (20 micronewtons per square meter). I Frequency, Hz The number of complete pressurie fluctuations per second above and below atmospheric pressure. A-Weighted Sound Level, a sound pressure level in decibels as measured on a sound dB le el meter using the A-weighting filter network. The A- w ighting filter de-emphasizes the very low and very high fr quency components of the sound in a manner similar to the fr uency response of the human ear and correlates well with subjective reactions to noise. All sound levels in this report are A-weighted. L10, L50, L90 e A-weighted noise levels that are exceeded 10%, 50%, and 9 % of the time during the measurement period. Equivalent Noise Level, Lei The average A-weighted noise level during the measurement period. j Community Noise The average A-weighted noise level during a 24-hour day, Equivalent Level, CNEL obtained after addition of 5 decibels in the evening from 7:00 pm to 10:00 pm and after addition of 10 decibels to sound levels in the night between 10:00 pm and 7:00 am.1Day/Night Noise Level, Ldn a average A-weighted noise level during a 24-hour day, o tained after addition of 10 decibels to levels measured in the ni ht between 10:00 pm and 7:00 am. Day/Night Noise Level, Ld, a average A-weighted noise level during a 24-hour day, of tained after addition of 10 decibels to levels measured in the night between 10:00 pm and 7:00 am. Ambient Noise Level I e composite of noise from all!sources near and far. The n rmal or existing level of environmental noise at a given to ation. Intrusive at noise which intrudes over and above the existing ambient • n ise at a given location. 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'.- \ : ,...% \v. :,••.,•::.7-1:,. __,..._ - .1-.!........f /.. . ......::z,', ...:2_".-•_*•_,-__•"- .s; ; „ ..p '-- k• -rs..., . . . . ' ! -:. . • .1\ --, -•:-..-.J -L--,---0.---..‘-- ,•-• -:'•••---• - -----`-- - • • ""'--;-- ..*7-7= .. ••• . v •",, - ''• ''. ,, „„, ' :. - . ..(,..., •i ..*: --',>,,,, -'• ..z;.i.__ !'"i •: - . • • .. • -_ . 1 •:;,..-...-,-- •.-: I.:- ,. . =.....; `-.• .• „ FPK'r • •s'i7 :••• .-''' .'' • A.' -- .. ,. -..... ... 4. --''' ; r:;.." .:., .\• .' •„ • 1 • ' .7.-• ' \• I .. •,'. . . •• . \ . ; ' ;':'.46*•/%4r.4::- •.'" , . t. . ' ." ."--' ‹, ..."-'4:".1.:.1-14-.....:f-••••:.r....-4:--': .•'•„2., ; _, .._ ,I, lo ,„) , ,,.- i , , . • - , - . ,. • --•,,7- ..0,..,,,,,I.. _, - ,,, _. , - . • ,/ • .v. •t . - • .. 1. , : • , , ,.• . - -:,.',„ ; .. • - • .-% . -- • ,,... . ' ''''''' :-..'......-• ''' :,,i'•>' — '. .. -•. , ... . - .-, ''.• ,' f '' '. '..":.,2:' :'' I T)..... .. -.."-':.•f• ' .7 -.../..,-.. •. '0' -.'-' 1.1:1.1:- ----•.- •4•J'. I mmo.................._ •• • ,.:0. ..•. ,_ •.._ .••7,, ..,. . . 7'1, '1",. i __.. ' • .. t.-___'..;•,._ . 1/4.. •• • • - . N ....._... . i - . . . - FIGURE Project Vicinity Map 1 • Ituiroclotron-rm 8 RcoKot,Iva • jai •,c.•,i, •c •, I•.. .11•:all ( 3 ) . ry • • Residenti 1 constructio in high noise level areas should include provisions for structural insulation as ecessary to ensure maximum possible damping. • Individual use of noise-generating apparatuses should not interfere with the normal use of enjoy ent of outdoo or indoor areas on surrounding properties. The Noise Elem nt also contai s standards which would regulate the noise which could be generated from re land uses t at affects another. Property line noise levels are limited,to 60 dBA during t e daytime an.! 50 dBA during the nighttime. An L� of 60 dBA is the goal that many communities have e.tablished for the maximum allowable noise environment in residential outdoor areas and ill be used in this report. Construction Ac ivity • Noise generated from c•nstruction equipment should be attenuated to the maximum extent possible. • Hours of construction .ctivities should be regulate d as much as reasonably possible to ensure minimum im.act of noise on surroundin i residential properties. EXISTING NOISE ENVIRO I ENT A noise monitoring survey was conducted in order to quantify existing noise levels at the site. - Noise levels were monitored o er a continuous 24-hour period at one location (Location A) and for short periods at seven dditional locations on the kite. The measured locations are shown on Figure 2. The 24-h.ur measurement provided the hour-by-hour variation in noise levels. Variatio s in the noise environment throughout th parcel were determined through the short-term measurements. he hourly distribution of Oise levels monitored at Location A are shown i Table 2. T e measured Ldn at Location A was 60 dBA. The noise environment is completely do i inated by Interstate 280 traffic. The roadway is elevated slightly with re ect to the sig- and is shielded from the site by hills adjoining the road, substantially red cing the site'' noise exposure. (4) . : . .- 2''''77:0.• --) 1' c '1 ' . \-- ----1 , \ , I , .. . • , •.4,:;,•-,),:.• s,.. • ‘ • - ___ i , .• . . , 1 , . . • . 1 ' . I , . • . . l• 1 ,' , , I . • ‘ / ...I ' . .,- , ' I I • ' / ..-- I , . , )•• • t. . `..• .. \ / —1 • ,•' / . ,," . • / . . • . , 1 ..., k. ,' . . \ (......) :.,'\ . . .. i 1 c • • . „ 1 • . , . ®, 1 .f.:...\ I ,f ‘i L.I.)• 1 - , I __,....._'--.-- • •-7--- ---_.__,, . i . ..1, • , .....,,_ / I . . __. .. • / ._ • -1.& • i r. .•-• •.; ,...: , , I ,...:\ --- . • /. i'' . / / • -..I., -N's\\ C ) • • l' . .--- • , % / ‘ \\ . ),, // / , -7 ' , - •- • ‘. 2//', .7'11 : . 11 ' \ •• :...Y 1 11 re .' , • 1 ) _,•• 1 Ul ' I ''• .. i . !cc( 'I ' . ! (.1. • \ Fo .-1 i ., I t.n ... ‘ •• \ .. ', • C---1 .IV ' 1 • , t 1....• , ! ' ; . , 1 . . ! \ a ., 1, \•. 1 • ,N\ : ....!, . . . p • . ,‘,... ., . . , ..... . , \ 1, • i. : , i : 30 .__ .0 •-• .„. t •k.\-, \ ., c.s., :, ; -----, . . .; '; \ • .• ,Ti , 1 ...,, _ _ , ,., i - I '_.) )' 4 D / ..... 1, \, 4 1 I ...... -.. ----.' -r--"1--- - . ,? 17—,----_ .. ! ^71. I 2\' • L ./t,:r4L. ____ . . ( [ t. -' ---\-e.•- .1 -.- ---•-•=ji-:1—___.---•'L-1 I2--.:„...- ____....--- i 1 i . Z,';-;•----__.--------- _ -j, ••• .----- ---- , 1 i : \ 1 •_-----• _------- • ••- • • 4_, '1 .1 : / „••'" .....------- ....-- ---- I ! . ... •••••••••••••••----- „,IN, (/ i...._ 1 1 i .. .____,,...• -•—••• • ••• - . ) F I G U if7 2 , Ifs I INGwoPTA.^ 5' 17PrOKIPf INC, _, .. ' TABLE 2 Continuous Hourly Noise Measurements Location)A 100 Ft. From Purissima Rd ; 12 Ft. High in Tree (see Figure 1) Date Hour Beginning Leq' May 21, 1992 2:00 pm 57 3:00 pm I 59 4:00 pm 58 5:00 pm 59 6:00 pm 58 7:00 pm 56 8:00 pm 56 9:00 pm 55 10:00 pm 54 11:00 pm 52 May 22, 1992 Midnight 51 1:00 am 48 2:00 am I 46 3:00 am 46 4:00 am 48 5:00 am 54 6:00 am 59 7:00 am 60 8:00 am 59 9:00 am 57 10:00 am 57 11:00 am I 57 12:00 pm 57 • 1:00 pm ; . 56 L42 = 60 dB Lin— The-average A-weighted noise level during the measurement period. I 2 La, (Day/Night Sound Level. — A descriptor established by the U.S. Environmental Protection Agency (EPA) for the 24-hour average A-weighted noise level. Sound levels during the hours from 10:00 pm to 7:00 am are penalized 10 dB to account for the increased sensitivity of people during the nighttime hours. ( 6 ); s The results of m Isurements at cations 1 through 7 are summarized in Table 3. The short- term measurements were correla ed to the 24-hour measurements made at Location A. The 24-hour average Ld„ were then estimated for each location. The entire site's noise exposure ranges from an L of 52 to 60 dBA. III E IMPA T A MENJF Potential nise impacts associat-• with this project fall in the following categories: • The comp tibility of the ioroposed residential use with the noise environment at the site. • The poten "al long-term noise impacts of onsite (noise generation from typical residential development d offsite traffic noise impacts. • Short-term construction oise impacts. The existing noise environment t the site ranges from an La, of 52 to 60 dBA. Existing outdoor noise levels are, theref re, compatible with the proposed residential development without additional mitigation. xisting and future traffic volumes for the Interstate 280 corridor were studied in the 990 MTC Regional Transportation Plan EIR (Brady & Associates, 1991). The noise assessment prepared for the EIR found that noise levels are not going to increase Ion this'portion of the I-280 corridor. The noise environment at the site is compatible with the proposed re idential development. Typical California construction ith the windows open for ventilation provides about 15 dBA of noise reduction when going from outside to inside. Twenty to 25 dBA of noise reduction is typically achieved with windo s closed. The existing and future Lan at the site is 60 dBA or less. Interior noise levels woui d be 45 dBA or less with windows open or closed. Interior noise levels would, therefore, onform with the town's 45 L1 goal without additional mitigation. The proposed residential develoiment of the site is consistent with the,existing residential development in the area. While the noise of lawn mowers and voices may occasionally be audible at existin residences, the overall noise environment would not noticeably or measurably change significantly. Allowable noise levels are regulated by the Town's noise standards. No significant adver•e noise impacts upon exist ing residents would result from • the new neighbors) . (7) a -- TABLE TABLE 3 Short Term Noise Measurements May 21, 1992 (see Figure 1) Time Est. Location Starting Duration Le, Lax Lmm Loi L10 L50 L90 Li Comments 1 1:15 pm 15 min. 56 64 50 61 58 56 53 60 90 ft. from Purissima Road; mostly I-280 traffic noise; one jet at 59 dBA 2 1:45 pm 15 min. 55 65 50 50 57 54 52 59 75 ft. from Purissima Road; mostly 1-280 traffic noise 3 2:15 pm 15 min. 55 63 48 59 57 54 51 58 Eastern end of site; top of hill — — — — — overlooking I-280; I=280 noise -- 4 4 2:45 pm 15 min. 49 57 44 55 51 48 46 52 End of Canario.Way; east side of ridge; I-280 noise; one jet at 57 dBA 5 3:12 pm 10 min. 55 62 48 60 57 54 52 56 Near southern property line; 1-280 traffic noise; one jet at 54 dBA % 6 3:25 pm 10 min. 58 64 54 62 60 58 56 59 Overlooking 1-280; exclusively I-280 noise 7 3:40 pm 15 min. 58 70 51 63 60 57 54 59 Mostly I-280 noise; one general aviation plane at 70 dBA Y Traffic noise levels in the area .re dominated by Interstate 280. The addition of trips on Purissima Road would not notic-:bly or measurably affect the noise environment in the area. No significant noise impacts wo Id, therefore, result from this project. Construction activities would to porarily°elevate noise levels at the project site and at the nearby residences. Adherence to the Town's Noise Element policies regarding construction noise would mitigate this potentia impact to a less than significant level. Noise-generating construction activities on the sit- should be limited to Monday through Friday, 8:00 am to 5:00 pm. All conktruction equi.ment should be properly muffled and maintained. • (9) a May 21, 1995 Mr. &Mrs. Jerry Anderson 12829 Canario Way RECEIVED Los Altos Hills, Ca 94022 MAY 2 3 1995 Town of Los Altos Hills Planning Commission TOWN OF LOS ALTOS HILLS Dear Commissioners: • We attended the meeting on May 10, 1995,with regard to the Lindy property• on Purissima Road. Our backyard joins this property on the north side. When we purchased our lot in 1972,this property hada an old little house on it. The Brubacker's had just sold this property to the Shecter's,who kept it in it's original condition. We have a problem with this developer building Three large homes on this land,two of which are to be two story structures, 6,000 sq. ft. in size and looking into my backyard and my horse barn. My home and the Pilling's home would loose our view of the beautiful hills above 280. We moved here to get out of the city,to enjoy the rural nature of our Town, where all of our neighbors have enjoyed for years. I know this is supposed to be progress,but where is the herd of deer going to go that has been feeding on this property since we have lived here. I wish you would consider allowing only one single story dwelling which would stay in keeping with our neighborhood. Sincerely, • • • ' O"he Lindy group - Dennis D. Paboojian President May 31, 1995 Sheryl Kolf Assistant Engineer Town of Los Altos Hills 26379 Fremont Road Los Altos Hills, CA 94022 Re: Deer Creek - Barrie Coates' "Assessment of Expected Effect" Dear Sheryl: As we discussed here is the report prepared by Barrie Coates entitled "An assessment of the expected effects of proposed grading on trees at the Deer Creek Project, 27591 Purissima Road, Los Altos Hills" dated January 12, 1995. There is one correction that needs to be made as the report was prepared prior to the finalization of the Leach Field layout. The correction occurs on Page 1 and relates to the primary leach fields; Specifically, I "Primary leach field installation poses danger of root damage to trees #57, 58, 59 (on lot 2) and 27 (on lot 3)." This sentence should read, "Primary leach field installation poses danger of root damage to tree #59 (on lot 2)." As always, tha you for your time and consideration towards my project. If you have any further cone ms or questions, please contact me at 408-255-4300. Sin ' •ly-'"Th J % lin Nn D. Paboojian 0 era Manager 12280 Saratoga-Sunnyvale Road •Suite 101 •Saratoga, CA 95070 • Phone: (408) 255-4300 • Fax: (408) 255-0646 ' BARRIE D. COATS and ASSOCIATES Horticultural Consultants 408-353-1052 23535 Summit Road,.Los Gatos,CA 95030 AN ASSESSMENT OF THE EXPECTED EFFECTS OF PROPOSED GRADING ON.TREES AT THE DEER CREEK PROJECT. 27591 PURISSIMA ROAD, LOS ALTOS HILLS Prepared at the Request of: Shannon Paboojian The Lindy Group 12280 Saratoga Sunnyvale Road, Suite 101 Saratoga,. CA 95070 Prepared by: Barrie D. Coate January 12, 1995 Job #2=94-041B BAIZRIE D. COA and ASSOCIAT S I Horticultural Consultan 408353-1052 23535 Summit Road,Loi Gatos,CA 5030 AN ASSESS NT OF THE EXPECTED EFFECTS OF OPOSED GRADING ON TREES AT DEER CREEK PROJECT, 27591 PURLS IMA ROAD, LOS ALTOS BILLS . Purpose of this Report This report will offer comments o the expected effects of the proposed grading and construction on the existing trees and offer preservation measures related to the trees on- the property at 27591 Purissima oad, Los Altos Hills. Findings There are 72 trees of significance on the property. This includes 24 Coast Live Oak, uercus agrifolia, 1 Valley Oak, Quercus lobata, 1 Cork Oak, Quercus suber, 32 Coast Redwood, Sequoia sempervirens, 1. Giant Sequoia, Sequoiadendron gigantea, 11 Canary Date Palms, P oenix canariensis, 9 Deodara.Cedar, Cedrus deodara, 1 Arizona Cypress, Cupressus glabra, 1 Bay Tree, Umbellularia californica, and 1 Coast Beefwood, Casuarina cunnin!hamiana. '. Driveways shown would remove tr-es #35, 36, 37, 38, 11 and 12. Trees #11 and 12 are Coast Redwoods of p for health and #35 through 38 are Date Palms of which there are 7 more lining Purissimd Road. Primary leach field installation po es danger of root damage to trees #57, 58, 59 (on lot 2), and 27 (on lot 3). This damage c. be mitigated, in my opinion, by avoiding digging trenches closer than 7 times the i nk diameter from the trunk (7 feet or further from a 12 inch diameter tree). Ten trees should, in my opinion, •e removed due to poorhealth and or structure or due to canopy competitionIlith more im•ortant trees. . They are Coast Live Oaks #3, 7, 8, 44 and 28. . Coast Redwoods #15, 22, 65, and Deodara Cedar #71, Giant Sequoia #51. 1 =r AN ASSESSMENT OF THE EXPECTED EFFECTS OF PROPOSED GRADING ON TREES AT THE DEER CREEK PROJECT, 27591 PURISSIMA ROAD, LOS ALTOS HILLS Other trees in marginal condition for which removal should be considered include Coast Redwoods #16 and 41 In summary, 13 trees should or could be removed for technical reasons. Tree Condition The largest. most prominent Coast Live Oak trees on the property (#1, 2, 3) have been severely overthinned in the past and are vulnei able to dropping large limbs. Unfortunately most of the limbs have too few major branches remaining to make crown restoration successful. Cabling and fertilizing are the only option. Many of the Redwoods have very thin canopies (as #11, 12, 13, 41). One has apparently been drought stressed (#22) or for other reasons, iti root activity is poor and has become infected with Botryospheria fungus and should be removed. Preservation Recommendations Leach field areas 1. No trench should be cut closer than 7 times the diameter of the trunk of a preserved tree to the trunk. (A trench 7 feet from a 12 inch diameter tree is acceptable). 2. Trenches may not be cut within 10 times the trunk diameter on more than one side of a given tree. I 3. Proposed leach line locations must be staked out, and protective fences.installed 2- 1/2 feet from the leach line, between the leach line and the tree trunk and•to.the drip line - of the balance of the canopy for each potentially impacted tree to prevent all tractor activity beneath the canopy. 4. Wherever connecting trenches can be located 10 feet or moreaway from the dripline of a tree rather than beneath or close to a tree canopy, that should be done. 2' AN ASSES MENT OF THE EXPECTED EFFECTS OF ;ROPOSED GRADING ON TREES AT T o' DEER CREEK PROJECT, 27691 _ - -. 'SSIMA ROAD. LOS ALTOS HILLS :, Roadway Areas 1. Roadway locations should be arranged beyond tree canopy margins (driplines) ` wherever possible. In the case o trees #1 and 40 this will not be possible. 2. Trees which will have roa•s constructed beneath their canopies must have protective fences installed before rough gr.ding begins, 2-1/2 feet from the margin of actual road edge and shall not involv cuts more an 6 inches deep beneath any tree canopies. 3. If more than 15% of the - i ea beneath the canopy of a preserved tree is to be covered with roadway; pervious paving, s b-grade aeration devices or other methods of assuring access by air and water to cover:d roots must be provided (note enclosure). Trees #11 and 41 Bridge reconstruction will require activity virtually touching tree #11, a 20 inch diameter Coast Redwood in marginal condition and tree #44, a Coast Redwood in marginal health. If road alignment further from #- 1, which results in the removal of trees #11 and 12 is practical, that should be done to reduce impact on tree #41. Protective wrapping as 3 layers •f snow-fencing or chainlink fence from ground to 8 feet above ground shoul be installed around the trunks of any trees like #1, 27, 26, which are close enough'to construction acti 'ty for trunks to be damaged by equipment. In the case of trees 1, 2, 4 and •, a fence must be installed at the tree trunk on the north side to extend to the dripline of ees #1 and 2 on the east and south. The same approach must be used around tree #40. • Storm Drain Trenches All storm drain trencl hes should •e located on the plans and be designed to avoid traveling beneath or within 10 feet of can pies. 3 . . AN ASSESSMENT OF THE EXPECTED EFFECTS • OF PROPOSED GRADING ON TREES AT THE DEER CREEK PROJECT, 27591 PURISSIMA ROAD, LOS ALTOS HILLS non-Construction Areas Fences must be constructed before equipment arrives on site at least 5 feet beyond drip lines to encircle individual trees or groups or trees which are not near actual construction, as #14 and 16, 17 to 19, 40, 52 to 54, 59, 70, 64, 66 to 69 to prevent compression of soil beneath canopies of trees by pickup trucks, tractors or automobiles. The submitted plan has placed roadways andlhomesites in locations which cause the least damage to retained trees while complying with the various requirements imposed on the site. Respectfully submitted, Barrie D. Coate BDC:la Enclosures: Charts . _ 4 O CI C. L. - 1 (CII > 0 0 "6 .....&. CO Co CD 03 V a) al -o- (a •ra m m 44 _i I cn 0 co 0 0 0 WO- 0 0 M 0 0 0 0 0 C 0 A) Du XI ID A) SD W 0.) 0:1 W cn ' co m cn W C CD CD Cc) o COD Re 00 2.7 7 w 71 0 7z 7 z 7 < 7 7 c "0 if 0 4 cp < 0 a CD (D CD CD CD 1 (D ST) -'7: .E. Ell CI CD , 0 33 cp * a) > 0 0 0 9 o, 0 0 0 0 9, 0 F, 0 FT; so a) A- ,c, o, 7k- 0. m A) A- X •CD w' 71C) 64 0 El 0 z „Lk' — . C:1 CD go L.,,) 0 • z iT) • 3 0 CD rrk CD CP MI 0 %V VI W I> w t•11 ? . ct" DBH(inches) A MULTI-STEM 4 0 i. DBH(inches) co • v) , 51 DBH(inches) co 0 co .41 4=.. cn cn - 4.1 HEIGHT co = 0 0 0 0 0 o C) co . .-,. I .. n) 4:. G.) 03 •--,1 ; SPREAD co ra 04 al , o 01 01 •0 I V N.) ...c. — N3 N.) •N3 —.. 1\3 . HEALTH(1-5) (-J z • 9: ^)I 03 STRUCTURE (1-5) g. co co co 03 C.3 .4. ' • CROWN CLEANING • I CROWN THINNING 'V . CROWN REDUCTION CROWN RESTORATION po cr CROWN RAINING S. REMOVE • . .p. ca ENDWEIGHT Z co co • ca. CABLES NEEDED 41 El) —a —n • PRUNING ....1. PRIORITIES (1-5) ' INSECTS (1-5) TREE CROWN .-. DISEASES (1-5) 17) ... DEAD WOOD (1-5) -13 D') TRUNK DECAY co ca 1-1:1 ROOT COLLAR COVERED 11-51 co S I ROOT COLLAR DISEASE (1-5 DIAMETER A IV ry 4), 0 in iyi • A m • --1 4,.. •P. AT 2 FT. . . . NEEDS FERTILIZER • NEEDS WATER 4_ 4_ 4_ RECOMMEND REMOVAL ' . REMO'III , i ,.. /1 D C.- C. __ " _ _. _ _ I (7731 CP ll > 0 0 N COm —I 03 CO . _. . , _, co CO ry " 0 CD cn.71 o o o o o • o o 44>0 0 0 . . 0 o cri 63 cb M a) (0 a) ) (0 (0 a (0 a) a)(0 (0 (0 D) a) CD = o Ro co ;). CD31 DJ 33 XI 33 D CD 33 D3 co Zr7 1:1 r-,•• ID CD CD CD C ›. 0 0 — a) 0. a a a a a 0. CD ST.). '41s, .5_ cc2 z 33 * * * * * * * cn > 0 0 0 0 0 . i0 0 0 •o P. -4 CD 0 0_ o a o a o 1 o a I a o o a a a) --", ""ai .._,;$ 0 2 . ,..,, . ...., CD . ) Lt.) n > - ,,,B- 0 ,-,,s, c0 3> ES 1-3 • o • E7, Cl) I cr) I 1‘, IV IV CO 1•—1 N) •—, —6 - 0 ..4. co DBH(inches) MULTI-STEM 4 CD co DBH(inzhes) E Ca) , . DBH(itches) (7, - co CD -. 1 CD co .CTI 4). HEIGHT co o o o 0 0 .0_,..........v....a......,____,o, 0 , a \ 4), CO CO CO CO CO I SPREAD CD iv 4). ry cn o o V 0 ry -... 1 CO CO IVN.) HEALTH(1-5) 01 STRUCTURE (1-5) g. -& ry ry _. C° ry C.) CROWN CLEANING CROWN THINNING . P-O CROWN REDUCTION g .6.. CROWN RESTORATION n Ph) Cr CROWN RAISING tam)yr. ENDVEIGHT ZcD CD - a. CABLES NEEDED it c.) PRUNING I PRIORITIES (1-5) INSECTS (1-5) A 11:1 TREE CROWN co c0 DISEASES (1-5) " , 0 . DEAD WOOD (1-5) • TRUNK DECAY co o ROOT COLLAR or COVERED (1-51 ler (q) ROOT COLLAR DISEASE (1-5 V iv N ... DIAMETER 4). ry r‘) . c., .0 co •N.1 0 0ry C.11 CD AT 2 FT. NEEDS FERTILIZER • NEEDS WATER ..r.._ RECOMMEND REMOVAL . . REMOVAL ' 7•1 , . I Measurements ®Condition ® Pruning/Cabling Needs ® Pest Disease Problems U w O w �� BARRIE D. COATE H q � "`���"' &ASSOCIATES 'l 0 0 Zo w ' ` AA �? % t1 w N w A , , x@ F- N w •----. `? p� a w E-, � � � � p � p w a � a � PG Horticultural Consultants A E, A .A a U Md Tree# El a AIN HA A H oo aAE• � � o�a � f A , 0 xw _ N al <4 1 7 Coast Redwood 1p n o 34 2 2 20 18Coast Redwood 2 9 100 4 2 2 2 30 • 19 Coast Redwood 2 7 pp ?p 1 22 8 • 2 0 Coast Redwood . 2 9 no o 3 0 2 2 1 co-dominant leader 31 21 Coast Redwood • 24..... .. 90 25 2 2 • snag top ?7- • • —2 2 Coast Redwood- 1 8 60 20 5 _ dead — - — ——— — 19 q 23 Coast Redwood 24 110 30 1 2 27 2 4 Coast Redwood 27 110 30 1 2 30 JOB TITLE Deer Creek/Los Altos Hills • JOB #02-94-041A ' DATE 11-8-94 • . S 1=BEST, 5=WORST pg. 3 c, Measurements Condition Pruning/Cabling Needs01„. Pest Disease Problems 0. 2 _ a BARRIE D.COATE U U q '? 4 `e "`���� &ASSOCIATES OE'ti o el '? A L9:, t� a " .' r w A 2 Ca ? O V .aa P' H H A A `. U H a g x � k aw R a DA ow w 4141 4 � Horticultural Consultants x H a .y ,_., an � H V w U � �.., � � � (408)353-1052 m Q E+ U o > w r g U c4 F' 2 O �' x x 2 a � a o 0 0 ow o a ° w a � o ow N w w C>' � � t Plant Name 2 2 2 w WWFs s a aw til „ P1 3 as g 1-1A q a o0 22 H wMIX Tree# A A A m PG an U U U U OG U Z w U a s H p� V Qi A q A4 MIX • 25 Coast Redwood 32 1 27 110 20 2 1 36/29 26'Coast Live Oak 9 15 18 1 19 27 Valley Oak 9.4 10 10 20 35 1 2 28" Quercus lobata . 28 Coast Live Oak 10 15 20 1 3 remove for benfit of #27 27. — --: ----: - -- -- -- --- and neighbor's tree -- 29 Canary Island Date Palm 23 30 15 2 1 ... Phoenix canariensis 30 Canary Island Date Palm 23 30 15 2 1 - S1 Canary Island Date Palm 23 30 15 2 1 32 Canary Island Date Palm 23 30 15 2 1 JOB TITLE Deer Creek/Los Altos Hills JOB #02-94-041A - DATE 11-8-94 1=BEST, 5=WORST Pg.4 Measurements Condition Pruning/Cabling Needs ol. .44 Pest Disease Problems lio. IMO II 5q L9 o 40 0 2 BARRIE D. COATE • 0 2 N &ASSOCIATES v Horticultural Consultants . A vi, A A -.. 0 H 'p'4' . 1(DM .---' 2 Pis3 6 P4 IP1 A'-' '61 F+1-1 m El P lit , (408)353-.1052 a °,2 A a M Q NU ra >' 'Ri Pi OM ELI ul 0 rc,44 t-) E. E-; 02 CO 000 '-' (-1 (9 PI4 0 0 0 Ora I-1 0 PI t'l P4 4 E-' EOIN a a UM Tree# Plant Name 0 P4 M L44 CI P4 N. A A a2 m 0 U 0 0 rx o x pi U Pi 1:14 - - E-4 p4 () P4 A A 44 P4 ;4 04 P A • • 33 Canary Island Date Palm 23 30 15 2 . . • 34;Cana... Island Date Palm 23 .015 2 • . . . • . , • . . : .•• • .•• , • . .•• , : , • • , • , : . . • . .. . , 35 Canary Island Date Palm ' 23 30 15 2 • . • . . 36 Canary Island Date Palm . 23 38 15 1 . . . • • 37.Canary Island Date Palm 23 .. . 8 •1 • . . . 38 Canary Island Date Palm 23 -- 28 15 1 39 Canary Island Date Palm 23 35 1.5 1 1 40 Coast Live Oak 23 35 30 21 • 26 • . . , . . • • • _ . • . . • . . , . . • • , . ,. • : . . , . . . . . ., . . JOB TITLE Deer Creek/Los Altos Hills • • .' • • . • JOB #02-94-041A ' . DATE 11-8-94 . ' .. . _ , . • • • . . . . , 1=BEST, 5=WORST . . . . . •. • • Pg.5 . • . . v • Measurements-440 Condition Pruning/Cabling Needs i Pest Disease Problems op 0BARRIE D.COATE U U O A a &ASSOCIATES 11.1 uz 4 Tx a a ? A "' v. a I H w •----- `. 0 Qa a ' ' aE., Horticultural Consultants NE., A A ? W P.-1k, H pA = 2 M H ; o wn oA ,4OaN illit. a 41P1 m 1:443 9 ca 0 xEo0 0 06 e # 02U UUUxR0 RI a o U H a NA A � • ' 41 Coast Redwood 42 110 30 4 1 46 42 Coast Redwood 1 6 9 0 20 2 2 18 43;Coast Redwood 22 90 20 2 2 25 44 Coast Live Oak 24 30 20 3 4 damaging adjacent tree 4 26 4 45 Coast Live Oak 3 2 60 60 2 3 badly overthinned 3 36 46 California Bay124... 10 60 30 1 3 24.. Umbellularia californica 47 Coast Live Oak 33 . 35 60 1 35 1 1+ 4 36 ..... ....... 48 Coast Live Oak . 20 -4 18 22 40 80 1 3 3 3 2 4 36 JOB TITLE Deer Creek/Los Altos Hills . JOB #02-94-041A DATE 11-8-94 1=BEST, 5=WORST P9.6 . co II m \\�• vm mCDW ori cn A w rev 01 -� o = O n n O - n n cn , n. n . � Nr m o m m o o (D Eu- ro o o crt eocom w a c c Ro Oa v2i °7 a)• cna) 7 �. y O � 41' ELIa, f�D �D m N CCa.D CD C • CDZ a w XI D 0 El00O a w O O a 22. O . o w G O -j m w w w w — cD x p� 3 I vo w n Y • C Ka. 2 - y f� cn 7 I � N c ca cn cn 3 2 Fi cn o .p co :w N :co p I DBH(in.clLes) A L L MULTI-STEM 4 co co DBH(inches) . 0 ! DBH(inclLes) cp C) a) cp co 1 p 1 1 .. -P HEIGHT co ' cn cn O N co .- O O N N N -+ N ." W 1 I SPREAD cn O cn O O .no O En7 i N) N W1 :1 1 :W 1 N HEALTH(1.5) a CO —• N :w N �, ! STRUCTURE(1-5) o: o CROWN CLEANING CROWN THINNING a 3 CROW REDUCTION to CROW oo ! RESTORATION a CROWN RAKING co e. HEM°VE ENDWEIGHT 1:'-c: o o CABLES NEEDED # R' PRUNING PRIORITIES (1-5) INSECTS (1-5) A. TREE CROWN CD v' . DISEASES (1-5) DEAD WOOD (1-5) ty TRUNK DECAY b . - ROOT COLLAR °cam. --. COVERED (1-5 ' ROOT COLLAR P) • DISEASE (1-5 V 1 N 1 co N 1 N DIAMETER CD 0 CD in N w. 1 c".... : AT 2 FT. NEEDS FERTILIZER NEEDS WATER • RECOMMEND REMOVAL If REMOVAL pipernRiTp 4.1 %II -- 13 .4. C- c- CO ll > 0 0 as ....A. co. ,C0 -I CD Ca 0) 0) cm .co 0) (r, cri cri CD 03 I\.) " ' 0 GO • 03 - 4* 000 0 0 0 •0 CI 0 W :4 al 8 p . . . 0 0 . 0 0 0 IP 40 'If: m a) 0 R. . w 21 a tv o a) a a) u) a) a co co = g R COD ._ . 0 r el) 7 ri ei) 7 M ›. 0 '.!: a) < a) ca X a) 0 ca0 c) co • co R m ST) ZE giz M c o. a = E 0 i.L• 0 cr 0 0 0 0 0 0 --I c7 CD CD 7C " A) A' --% A) X a) . -I CA 7 ....... ...„ — . p co ..) n o> 3 .5 g tl 2 . a) ;._,; ,: ci) (I) , 1-3 4' FE a c7-7 tmi o • cro , cri _n _.. •-` DBH(inches) no o" o-' .c.0 co co co cri 4._ -e.... MULTI-STEM DBH(incites) a) . co ,-% DBH(inches) CD I n) -& n) n) _.. ca r‘) 1 HEIGHT CD o o 01 0 0 cri 01 01 o cf) — . n o SPREAD N -.. HEALTH(1-5) 0 a fa: • ,n) N) cSTRUCTURE (1-5) g.o -, • _.. :0) a) a, , , a • • , • CROWN CLEANING CROWN THINNING cr I CROWN REDUCTION o. alw o CROWN < • a) RESTORATION e5 co = _ CROWN RAISING ' m . .. = ., it Emu V t, a cp ENDWEIGHT Z N) co co 0.. CABLES NEEDED # c4 ..... , • PRUNING PRIORITIES (1-5) . INSECTS (1-5) A ! 'V TREE CROWN co (.3 , B ' DISEASES (1-5) • , ,— DEAD VOOD (1-5) (6' TRUNKDECAY co ROOT COLLAR 0 a' COVERED (1-51 Frr ROOT COLLAR ---- --- DISEASE (1-5 -• _ Ir -4,— DIAMETER _. _. .. " i 4). CO .../ 0 -.1. CO CO V AT 2 FT. NEEDS FERTILIZER NEEDS VATER --1 RECOMMEND . I REMOVAL [ REMOVAL Measurements Condition Pruning/Cabling Needs 0.. .4 Pest Disease Problems ii... ON- -illi A * ' a 0 BARRIE D.COATE 2 q Fil 2-- &ASSOCIATES 0 4Z 1;7 — - 1: _L-7 Ed ivLi r4 A 2 g a rticultural Consultants r±i (9 rzi r4 r-1-1 n 0E1 841 P4 . w A > to. P- (408)353-1052 0 N ric,!,2 9,2 oocq _ H ''' 0 0 0 ov2 il 2 r4 pla 0, 0 P4 ,1 Ill 41 U X{ ail i. - P14 Tree# HoPlant Name PI 0 '' ik- Fil fo-21 (cj kcj G4 ij 'cl4' 242 o ,4. fll R fl n Ec5. ° ° C) 4 H G144141V —65-Coast-Redwood 1-5 20-12 —2-4 f7 li 66 Arizona Cypress 12 q 10 10 28 25 3 1 18/12 Cupressus glabra 67 beodar Cedar 10 28 18 2 1 12 68 Deodar Cedar 10 11 6 25 15 3 1 . . 12/6 69'Deodar Cedar 12 30 15 1 2 13 • —7-0-Coast-Beefwood ' 2-4 25t8 —1-4- has-been topped-- 2T Causarina cunninghamiana 71 Deodar Cedar 17 40 30 3 3 girlded at 8' 19 li 72 Deodar Cedar 19 40 35 2 1 21 . . JOB TITLE Deer Creek/Los Altos Hills ' JOB #02-94-041A DATE 11-8-94 1=BEST, 5=WORST , ot pg.9 . A BARRIE D. COA fE and ASSOCIATES Horticultural Consultants 408-3534052 23535 Summit Road..Los Gatos.CA 95030 ASSUMPTIONS AND, LIMITING CONDITIONS 1. Any legal description provided to the appraiser/consultant is assumed to be correct. Any titles and ownerships to any property are assumed to be good and marketable. No responsibility is assumed for matters legal in character nor is any opinion rendered as to the quality of any title. 2. It is assumed that any property is not in violation of any applicable codes, ordinances, statutes,or other governmental regulations. • 3. Care has been taken to obtain allinformation from reliable sources. All data has been verified insofar as possible;however,the appraiser/consultant'can neither guarantee nor be responsible for accuracy of information provided by others. 1 4. The appraiser/consultant shall not be required to give testimony or to attend court by reason of this appraisal unless subsequent written arrangements are made, including payment of an additional fee for services. ' - 5. Loss or removal of any part of this report invalidates the entire appraisalevaluation. 6. Possession of this report or a copy thereofdoes not imply right of publication or use for any purpose by any other than the person(s)to whom it is addressed without written consent of this appraiser/consultant. • 7. Neither all nor any part of the contents of this report, nor copy thereof,shall be used for any purpose by anyone but the client to whom it;is addressed;without the prior written consent of the appraiser/consultant; nor shall it be conveyed by anyone,.including the client,to the public through advertising, public relations, news,sales or other media,without the written consent and approval of the author, particularly as to value considerations, identity of the appraiser/consultant or any professioinai society or institute or to any initialed designation conferred upon the appraiser/consultant as stated in his/her qualifications. • 8. This report and the values expressed herein representthe opinion of the appraiser/consultant, and the appraiser's/consultant's fee is in no way contingent upon the reporting of a specified value nor upon any finding to be reported. 9. Sketches,diagrams, graphs, photos,etc. in this report,being intended as visual aids, are not necessarily to scale and should not be construed as engineering reports or surveys. • 10. This report has been made in conformity with acceptable appraisalevaluation/diagnostic reporting techniques and procedures, as recommended by the International Society of Arboriculture. AN ASSESSMENT OF THE EXPECTED EFFECTS OF PROPOSED GRADING ON TREES AT :1 DEER CREEK PROJECT 27591 P ' SIMA ROAD,LOS ALTOS HILLS - • ERRATA SHEET On page three of subject do ent; incorrect reference is made to tree#44, a Coast Redwood as follows: "Trees#L 1 and 41 Bridge reconstruction ' ' require activity virtually touching tree#11, a 20 inch diaiieter Coast R-•wood in marginal condition and tree#44, a Coast Redwood in marginal h-alth. The above paragraph is hereby orrected to read as follows: Trees#.1L and 41 .. Bridge reconstruction require activity virtually touching tree#11, a 20 inch diameter Coast R-•wood in marginal condition and tree#41, a Coast Redwood in marginal h=alth. This Errata Sheet, once execute by Barrie D. Coate, becomes a part of the above entitled report and officially corrects th reference to tree#44.in the original document. Signed: BARRIE D. COATE AND AS OCIATES By: Barrie D. CI ate.. Date • 501 ANlt,ALr.�buuit LS ttLl'(rKtI 27591 PURISSIMA ROAD,LOS ALTOS HILLS, CA SETTING The project site is a four-acre parcel! on the east side of Purissima Road, between Elena Road and Viscaino Drive in Los Altos Hills, California. A three-lot subdivision is proposed. This botanical resources report provides supporting information for an Initial Study that is required under the California Environmental Quality Act (CEQA). The site is flat from Purissima Road to just east of Deer Creek, which flows across the site generally from south to north. Deer Creek is defined as an intermittent stream on the USGS Palo Alto quadrangle; it has been observed to flow in the summer (S. Paboojian, personal communication). From the creek to the eastern edge of the property the topography slopes up to a knoll between two swales. The site was previously developed with a single family residence which has been removed. Surrounding land uses are residential. METHODS A site visit was made in late May 1995 to determine vegetation communities and whether the habitat of sensitive plant species is present on site. The California Native Plant Society Inventory of Rare and Endangered Vascular Plants was consulted for a listing of rare plant species known to occur in the area. Personnel from the California Department of Fish and Game were also consulted regarding agency concerns. Information regarding trees is based on a tree report for the site prepared by Barrie Coate and Associates (February 17, 1994). RESULTS There are two vegetation communities at the site: a riparian zone along the creek, and non-native annual grassland with native and ornamental tree plantings over the rest of the site. The site has been significantly affected by previous use and does not contain rare plant species or the habitat which could support rare plant species. The riparian zone is a narrow band of water-dependent vegetation along Deer Creek. The dominant tree is Coast redwood (Sequoia sempervirens), which was planted there; other trees in the riparian zone include Coast live oak (Quercus agrifolia), English walnut (Juglans sp.), European olive (Olea europaea), California bay (Umbellularia californica), and Willow (Salix sp.). The dominant understory species is Periwinkle (Vinca major); other.understory plants include California blackberry (Rubus ursinus), California rose (Rosa californica), Mugwori (Artemisia douglasii), and Elderberry (Sambucus sp.). Outside of the riparian zone the site contains non-native annual grassland dominated by oats (Avena barbata) and rye grass (Lolium multiflorum). Other species observed which represent the disturbed nature of the grassland include Ripgut brome (Bromus diandrus), Vetch (Vida sp.), Foxtail barley (Hordeum jubatum ), Dock (Rumex crispus), Bur clover (Medicago sp.), Mallow (Malva parviflora), Bristly ox-tongue (Picris echioides), Radish (Raphanus saliva), and Italian thistle (Carduus pycnocephalus). May 30, 1995 Thomas Reid Associates .,v,u„u,al Resu,.,yes rcepu,, _i)91 r.. wall rage 2;* <_ r Trees outside of the ri arian zone include Coast live oak (16 trees), Valley oak (Quercus lobata 1 tree), Cana y island date palm (Phoenix canariensis; 11 trees), Giant sequoia (Sequoiadendron giga teum; 1 tree), Deodar cedar (Cedrus deodara; 9 trees), Cork oak (Quercus suber; 1 tree), Arizona cypress (Cupressus glabra; 1 tree), Coast beefwood (Casuarina cunning/l}amiana ; 1 tree), and several different fruit trees, which were found to beI in poor condition by Barrie Coate and Associates. IMPACTS The driveway for the pfoject requires the removal of seven trees, including two Coast redwoods, four Canary Island date palms, one Giapt sequoia, and one Deodar cedar. One Coast live oak would be affected by the leachfield for lot 2. The tree report documents 72 trees at the site most of which are healthy, and would be retained. The project would not affect any rare or endangered plant species. The project would not result in significant impacts to botanical resources. MITIGATION � Although the removal of seven trees by the project is not a significant impact, the California Department of Fish and Game recommends the replacement of oak trees removed by development in o oder to replace wildlife habitat. The replacement ratio is three trees planted for each tr•e removed. One Coast live oak tree would be adversely impacted by the leachfield for lot 2. It is recommended that a grouping of three Coast live oak trees be planted at th• project site, as mitigation for the loss of this tree. REFERENCES Literature Barrie D. Coate and • .sociates. February 17, 1994. "A Survey of the Health and Structure of therees at the eer Creek Project 27591 Purissima Road Los Altos Hills". Barrie D. Coate and Associate Horticultural Consultants, 23535 Summit Road, Los Gatos, CA, Job #02-94-041. California Native Plant Society. May 30, 1995. "inventory of Rare and Endangered Vascular Plants o California - Full Data Report for Rare Plants on the Palo Alto Quadrangle". California Native Plant Society, Sacramento, California. 1 Hickman, James C., Editor. 1993. The Jepson Manual: Higher Plants of California . University of California Press, Berkeley and Los Angeles, California Persons Contacted California Department of Fish and Game Combs, Gary. Warden. DeWald, ,Jeannine. Wildlife Biologist. ' May 30, 1995 Thomas Reid Associates