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none, Drainage conditions, Correspondence• • Ca opeo PP•,.S JUL February 10,1995 Mr. Alfred Marin 2 Ranchero Road Rolling Hills, CA 90274 SUBJECT: DRAINING AND GRADING PLAN 2 RANCHERO ROAD (LOT 13-FT) Dear Mr. Marin: INCORPORATED JANUARY 24, 1957 NO. 2 PORTUGUESE BEND ROAD ROLLING HILLS, CALIF. 90274 (310) 377-1521 FAX: (310) 377-7288 Enclosed is a letter from Ms. Lata Thakar, District Engineer, describing the technical evaluation and comments from the Department of Public Works' Materials Engineering Division representatives, Mr. Dave Poppler and Mr. Mike Montgomery, following a meeting with them and Rolling Hills City Manager Craig Nealis on December 1, 1994 to discuss your Draining and Grading Plan for 2 Ranchero Road. Feel free to call me at (310) 377-1521 if you have any questions. Your cooperation is appreciated. Sincerel LOLA UNGAR PRINCIPAL PLANNER cc: Mr. Craig Nealis, City Manager COUNTY OF LOS ANGELES DEPARTMENT OF PUBLIC WORKS HARRY W. STONE, Director December 27, 1994 900 SOUTH FREMONT AVENUE ALHAMBRA, CALIFORNIA 91803-1331 Telephone: (818)458-5100 Mr. Craig R. Nealis City Manager 2 Portuguese Bend Road Rolling Hills, California 90274 Dear Mr. Nealis: EEIBEOWq: F c D 011995 City Of Rolling Hills ADDRESS ALL CORRESPONDENCE TO y o n Rnv 1 dan ALHAMBRA, CALIFORNIA 91802-1460 IN REPLY PLEASE REFER TO FILE: DRAINAGE AND GRADING PLAN FOR #2 RANCHERO, DATED JULY 7, 1994, CITY OF ROLLING HILLS, WHICH WERE INFORMALLY SUBMITTED AT GRADING PLAN PROCESSING CENTER IN ALHAMBRA, ON OCTOBER 26, 1994. At our meeting held on December 1, 1994 with Mr. Lynn Nicholson, Division Engineer, of our Materials Engineering Division, along with his staff Mr. Poppler and Mr. Montgomery, you had requested that we provide comments for the plans at #2 Ranchero, Rolling Hills. We have received the following technical evaluation and comments from our Materials Engineering Division. Their assessment is based on the site visit, references listed below and courtesy review of the plan informally submitted, without grading permit application and fees. References: 1. March 22, 1993 letter from Mr. Craig R. Nealis, City Manager, City of Rolling Hills, to the Honorable Mayor and Members of the City council - "Consideration of soil import/export schedule of fees approved by the Rolling Hills Community Association Board of Directors"._ 2. February 25, 1993 letter from Ms. Peggy R. Minor, Association Manager, City of Rolling Hills, to Mr. Craig R. Nealis, City Manager, City of Rolling Hills - "soil import/export". 3. March 4, 1993 report from Mr. David C. Breiholz and Company, Inc., to Albert Marin -"Surface Drainage Conditions at #2 Ranchero Road,. Rolling Hills, Ca; Job No. 93-038E". 4. March 16, 1993 letter from Alfred A. Marin resident of #2 Ranchero Road, to the Rolling Hills Community Association - Surface Drainage Conditions at #2 Ranchero Road, Rolling Hills. A. The subject plan proposes the interception, concentration, and discharging of surface runoff water into the nearby Paintbrush Canyon. The proposed drainage conduits, consisting of a trench and half -round metal drains, would traverse adjacent properties. As a general rule, the • Craig Nealis December 27, 1994 Page 2 modification of natural drainage and topography on properties or on active landslides, particularly where adjacent properties are affected, is prohibited by the City Building Code. Such proposals generally require easements, maintenance agreements, cooperation of homeowners, etc., to ensure that should disruption of the conduits occur as the landslide continues to move, the concentrated flow would not accelerate the landslide instability. B. The subject plan proposes grading to fill the active, large landslide headscarp fissures, which transects the subject property. According to Section 309 of the City Building Code, grading cannot be approved if it will be subject to landslide, settlement, or slippage. The proposed. grading will be subject to all three conditions. There is no assurance that the proposed grading will not adversely impact the subject property or adjacent properties. As an interim alternative measure, waterproof tarps or plastic could be utilized to cover the headscarp, preventing runoff from flowing into the open fissures during the rainy season. c. A recent visit to the subject property indicated that a substantial amount of material has already been placed in the aforementioned fissures of the active landslide headscarp. This grading has not been approved by the Materials Engineering Division. It is suggested that the owner be required to retain the services of a Geotechnical Engineer and Engineering Geologist to evaluate the effect of this grading, relative to stability of the adjacent property(ies) and the landslide. D. Further deterioration of the existing improvements should be anticipated, as slide movement and deformation will continue under current landslide conditions. A Geologic Hazard Abatement District may be warranted to assess current conditions for possible remedial measures and for required joint efforts of affected property owners. If you have any questions regarding this matter, please contact Mr. Michael Montgomery or Mr. Dave Poppler at (818) 458-4923 Very truly yours, HARRY W. STONE Director of Public Works _jcx LATA THAKAR District Engineer, Lomita cc: TR. DP. MM. • COUNTY OF LOS ANGELES DEPARTMENT OF PUBLIC WORKS HARRY W. STONE, Director December 27, 1994 900 SOUTH FREMONT AVENUE ALHAMBRA, CALIFORNIA 91803-1331 Telephone: (818)458-5100 Mr. Craig R. Nealis City Manager 2 Portuguese Bend Road Rolling Hills, California 90274 Dear Mr. Nealis: MEIBEllWEV FED 011995 City Of Rolling Hills ADDRESS ALL CORRESPONDENCE TO: i nntiny in,n ALHAMBRA, CALIFORNIA 91802-1460 IN REPLY PLEASE REFER TO FILE: DRAINAGE AND GRADING PLAN FOR #2 RANCHERO, DATED JULY 7, 1994, CITY OF ROLLING HILLS, WHICH WERE INFORMALLY SUBMITTED AT GRADING PLAN PROCESSING CENTER IN ALHAMBRA, ON OCTOBER 26, 1994. At our meeting held on December 1, 1994 with Mr. Lynn Nicholson, Division Engineer, of our Materials Engineering Division, along with his staff Mr. Poppler and Mr. Montgomery, you had requested that we provide comments for the plans at #2 Ranchero, Rolling Hills. We have received the following technical evaluation and comments from our Materials Engineering Division. Their assessment is based on the site visit, references listed below and courtesy review of the plan informally submitted, without grading permit application and fees. References: 1. March 22, 1993 letter from Mr. Craig R. Nealis, City Manager, City of Rolling Hills, to the Honorable Mayor and Members of the City council - "Consideration of soil import/export schedule of fees approved by the Rolling Hills Community Association Board of Directors". 2. February 25, 1993 letter from Ms. Peggy R. Minor, Association Manager, City of Rolling Hills, to Mr. Craig R. Nealis, City Manager, City of Rolling Hills - "soil import/export". 3. March 4, 1993 report from Mr. David C. Breiholz and Company, Inc., to Albert Marin -"Surface Drainage Conditions at #2 Ranchero Road, Rolling Hills, Ca; Job No. 93-038E". 4. March 16, 1993 letter from Alfred A. Marin resident of #2 Ranchero Road, to the Rolling Hills Community Association - Surface Drainage Conditions at #2 Ranchero Road, Rolling Hills. A. The subject plan proposes the interception, concentration, and discharging of surface runoff water into the nearby Paintbrush Canyon. The proposed drainage conduits, consisting of a trench and half -round metal drains, would traverse adjacent properties. As a general rule, the Craig Nealis December 27, 1994 Page 2 modification of natural drainage and topography on properties or on active landslides, particularly where adjacent properties are affected, is prohibited by the City Building Code. Such proposals generally require easements, maintenance agreements, cooperation of homeowners, etc., to ensure that should disruption of the conduits occur as the landslide continues to move, the concentrated flow would not accelerate the landslide instability. B. The subject plan proposes grading to fill the active, large landslide headscarp fissures, which transects the subject property. According to Section 309 of the City Building Code, grading cannot be approved if it will be subject to landslide, settlement, or slippage. The proposed grading will be subject to all three conditions. There is no assurance that the proposed grading will not adversely impact the subject property or adjacent properties. As an interim alternative measure, waterproof tarps or plastic could be utilized to cover the headscarp, preventing runoff from flowing into the open fissures during the rainy season. c. A recent visit to the subject property indicated that a substantial amount of material has already been placed in the aforementioned fissures of the active landslide headscarp. This grading has not been approved by the Materials Engineering Division. It is suggested that the owner be required to retain the services of a Geotechnical Engineer and Engineering Geologist to evaluate the effect of this grading, relative to stability of the adjacent property(ies) and the landslide. D. Further deterioration of the existing improvements should be anticipated, as slide movement and deformation will continue under current landslide conditions. A Geologic Hazard Abatement District may be warranted to assess current conditions for possible remedial measures and for required joint efforts of affected property owners. If you have any questions regarding this matter, please contact Mr. Michael Montgomery or Mr. Dave Poppler at (818) 458-4923 Very truly yours, HARRY W. STONE Director of Public Works LATA THAKAR District Engineer, Lomita cc: TR. DP. MM. DAVID C. BREIHOLZ AND •ANY, INC. • Engineering Design Construction 1852 Lomita Boulevard Lomita, California 90717 Email: 71673,2315@CIS Tel: 310-530-3050 Fax: 530-0184 November 2, 1994 Mr. Al Marin #2 Ranchero Road Rolling Hills, California 90274 RE: Erosion control, drainage and grading plan for property at # 2 Ranchero Road, Rolling Hills DCB Job # 94-248E Dear Al: Attached you will find the County's response to the plan we prepared and submitted for grading improvements and drainage upgrades for your property. Based on my meetings and telephone conversations with 1) Craig Nealis, Rolling Hills City Manager, 2) Lola Unger, Principal Planner for Rolling Hills, 3) Peggy Minor, Manager for the Community Association, 4) Lata Thakar, Los Angeles County District Manager for the Lomita Office (contract engineer for the City of Rolling Hills), 5) Mike Mongomery, Geologist for Los Angeles County, and 6) Dave Poppler, Chief Geologist for Los Angeles County, none of the agencies want to go on record of approving a plan for remedial grading to improve drainage on and over your property. All parties are willing to admit that storm drainage water from the City streets enters your property and exasperates the situation, but no one, at this point is willing to issue a permit to fill fissures or upgrade the drainage due to the perceived liability. The County has suggested that the property owners in the Flying Triangle Landslide area form a landslide abatement district and address the regional problems as a group. At this point, we feel that we have exhausted the available avenues for obtaining a grading permit. We will therefore stop work on this project until we receive further direction from you. Please feel free to call Dave or myself to discuss the City and County response to our plan submittal. Sincerely, Gary Wynn, 'P.E. Project Manager cc: David C. Breiholz Civil Engineering Structural Design Seismic Hazard Reduction Construction Supervision Plan Check Service Inspection Service 11-01-1994 08:15AM FROM ATERIALS ENGINEERING 70L261 LOS ANGELES COUNTY To: Lata. Thakar From M.Montgomery TO ip 913105300184 P.01 i ERGRAM Date 11/1/94 Subject Proposed Improvements #2 Ranchero, David Breiholz No 1 The submitted plan (dated 7/6/94) for drainage improvements and grading can not be approved. Please see our attached letter dated 8/19/9". cc:Day ,d Breiholz Michael Montgomery Materials Engineering Division D.C. k NE�HOL2 I� )C & CO.. INC. ) 0 NOV 1 1994 11-01-1994 08:1T441 FROM FINTERINLS EI1GIh1EERI1dG TO 91:105300184 P.02 August 19, 1993 TO: Tom Remillard Building and Safety/Land Development Division Attention Lata Thakar Lomita District Office Manager FROM: Victor C. Martine Materials Engineehg Division #2 RANCHERO ROAD - FLYING TRIANGLE LANDSLIDE CITY OF ROLLING HILLS References: D.C.1.hZ.I l7 2 & CO.. INC. EMU7L 1 `Nov 'f 1994 1." March 4, 1993 report from David C. Breiholz and Company, Inc., to Albert Martin - "Surface Drainage Conditions at #2 Ranchero Road, Rolling Hills, CA; Job No. 93-038E". 2. March 16, 1993 letter from Alfred A. Martin, resident of #2 Ranchero Road, to the Rolling Hills Community Association - Surface Drainage Conditions at #2 Ranchero Road, Rolling Hills, CA". The following comments are provided in response to a recent verbal request from Ms. Lata Thakar regarding remedial work proposed on the active Flying Triangle Landslide (see References 1 and 2): 1., The Reference 1 Report recommends modification of drainage _and/or grading of public street areas and.adjacent properties_ to lessen damage to #2 Ranchero Road, resulting from active landsliding. No plan or engineering geology and geotechnical engineering reports were submitted. 2. An active landslide scarp transects the subject property and has removed support from portions of the garage and deck footings. 3.' Comments in our May 20, 1993 memo (copy attached), on the Flying Triangle Landslide, are directly applicable to the modifications proposed for the subject property. 4., Only the geotechnical issues (not drainage) have been considered in our comments. If you have any questions, please contact Dave Poppler at (818) 458-4923. P:jas:pp/GI:RANCHERO ME-3 Attach. City opeolfin9. November 15, 1993 Mr. Alfred A. Marin 2 Ranchero Road Rolling Hills, CA 90274 SUBJECT: SURFACE DRAINAGE CONDITIONS AT 2 RANCHERO ROAD, ROLLING HILLS, CA Dear Mr. Marin: INCORPORATED JANUARY 24, 1957 NO. 2 PORTUGUESE BEND ROAD ROLLING HILLS, CALIF. 90274 (310) 377.1521 FAX: (310) 377-7288 Attached is the response from the Los Angeles County Department of Public Works regarding the surface drainage conditions at your property. Thank you for being so patient. Feel free to call me at (310) 377-1521 if you have any questions regarding the processing of a permit for alteration or minor repair of existing structures such as foundation retrofits as required. Thank you for your cooperation. Sincerely, ea Zit LOLA UNGAR PRINCIPAL PLANNER cc: Ms. Peggy Minor, Manager, Rolling Hills Community Association Ms. Lata Thakar, District Engineer, L.A. County Department of Public Works, Lomita Building and Safety Division Mr. David Breiholz, P.E., David C. Breiholz and Company, Inc. ®Prmre..1 on P., i'inrrl Pnnnr THOMAS A. T[DEMANSON. Director • • COUNTY OF LOS ANGELLS DEPARTMENT OF PUBLIC WORKS 900 SOUTH FREMONT AVENUE ALHAMBRA. CALIFORNIA 91803-1331 Telephone: (818) 458-5100 November 4, 1993 Ms. Lola Ungar, Principal Planner City of Rolling Hills 2 Portuguese Bend Road Rolling Hills, CA. 90274 Dear Ms. Ungar: SURFACE DRAINAGE CONDITIONS AT # 2 RANCHERO ROAD. CITY OF ROLLING HILLS, CA. OWNER: ALFRED A. MARIN References: 1) 2) As requested by letters, and we Er'iMaWg NOV081993 ,�,CITY OF ROLLING HILHILLS4'WDRESS.A.U.GDARES \CE TO: P.O.BOX 1460 ALHAMBRA. CALIFORNIA 91802-1460 IN REPLY PLEASE REFER TO FILE March 4, 1993 report from Mr. David C. Breiholz, P. E. President, David C. Breiholz And Company, Inc. to Mr. Albert Marin. March 16, 1993 Letter from Mr. Alfred A. Marin to Rolling Hills Community Association, City of Rolling Hills. you, we have reviewed the above referenced have the following comments: 1. As you know the topography of this area is changing due to an active landslide. This has resulted in diversion of the rain water runoff from the surrounding areas onto the subject property. 2. The Report from Mr. Breiholz recommends to have the drainage conditions improved on and around the subject property in order to protect the lot and extend the life of the house. He suggests to accomplish this by regrading the access road and an adjacent lot, and by replacing the soil on Mr. Marin's lot that was washed away, in order to stabilize the driveway and hardscape areas around the house. Mr. Breiholz is specific in his report, that the owner is not at liberty to do grading work within the boundary of his property without an approved plan and permit, and is not at liberty to perform any off -site work. However, due to the active landslide, the City Building Code does not permit issuance of a building or a grading permit within such area per sec. 308(b). Provisions of the City Building Code do not apply to the work recommended on the access roads owned by the Association. page-1 • • Ms. Lola Ungar November 4, 1993 Page 2 3. Review of geology maps for Flying Triangle area indicates that an active landslide scarp transects the subject property. This'situation along with heavy runoff concentrated at this location last season has eroded the soil supporting the footings of a portion of the garage/guest quarters. 4. About the proposal made by Mr. Marin in his letter, Reference 2 above, to replace the eroded soil by bringing truckloads of fill, our comments in May 24, 1993 letter (copy attached), regarding soil import/export policy within the Flying Triangle Landslide, are still valid and are applicable to the modifications proposed for the subject property. As stated in that letter; sealing of "minor" (3-12.i inches) fissures and scarps with earth materials or asphalt for driveways and access roads is desirable to mitigate or lessen infiltration of surface water. 5. Since this lot and the surrounding areas are all within the boundaries of the active landslide area, a permit, under all of the provision of section 308 (b) 3.c of the City Building Code, may be issued for the work involving the alteration or minor repair of existing structures such as a foundation retrofits as required. Upon submittal of the plans and supporting calculations, along with payment of appropriate fees, we will be happy to evaluate them as soon as possible. If we can be of further assistance, please contact the undersigned at (310) 534-3760. Very truly yours, T. A. TIDEMANSON Director of Public Works . Lc tc 1 aLir ,. LATA THAKAR District Engineer, Lomita. cc: TR, EB, BH. 4 COL*TY OF LOS ANGELS DEPARTMENT OF PUBLIC WORKS 900 SOUTH FREMONT AVENUE ALHAMBRA. CALIFORNIA 91E03.1331 Telephone: (E1E) 158.5100 THOMAS A. TIDEMANSON, Director May 24, 1993 Ms. Lola Ungar, Principal Planner City of Rolling.Hills 2 Portuguese Bend Road Rolling Hills, CA. 90274 ADDRESS ALL CORRESPONDENCE TO: P.O. BOX 1460 ALHAMBRA. CALIFORNIA 11301.1460 IN REPLY PLEASE REFER TO FIL_. Dear Ms. Ungar: SOIL IMPORT/EXPORT POLICY WITHIN FLYING TRIANGLE LANDSLIDE AREA, CITY OF ROLLING HILLS, CA. References: 1) March 22, 1993 Letter from Mr. Craig R. Nealis, City Manager, City of Rolling Hills, to Honorable Mayor.and Members of the City Council. 2) February 25, 1993 Letter from Ms. Peggy R. Minor, Association Manager, City of Rolling Hills, to Mr. Craig Nealis, City Manager, City of Rolling Hills. In response to your letter of March 25, 1993 regarding the above referenced letters, we are pleased to provide following comments. These comments relate to correction of surface ruptures, i.e. fissures and scarps created by landslide movement within Flying Triangle landslide area. Since this is an active landslide neither the County or the City can predict or provide assurance as to its future behavior even without any modification. 1. Being an active landslide phenomena, it is sensitive to modification of topography and drainage. As a general rule,' modification of topography and drainage on properties on active landslides, particularly where adjacent properties are affected, is prohibited by the City Building code. 2. No assurances can be provided that importing additional materials or grading of this site will not adversely impact the area or adjacent property. 3. The sealing of "minor" (3-12 ± inches) fissures and scarps with earth materials or asphalt for driveways and streets can mitigate or lessen infiltration of surface water. 4. "Major" (several feet high) landslide head scarps and head areas may require several truck loads of earth • Ms. Lola Ungar May 24, 1993 Page 2 materials to re-establish access. The weight of these materials could surcharge and decrease the stability of the landslide. Re-establishment of access in this manner involves substantial risks of adversely affecting the stability of the area. 5. Further deterioration of existing improvements should be anticipated, as slide movement and deformation will continue under current landslide conditions. Creation of a Geologic Hazard Abatement District to assess current conditions for possible remedial measures may be warranted. The above comments are based upon evaluation and assessment of the Flying Triangle landslide phenomena by our Materials Engineering Division. If we can be of further assistance, please contact the undersigned at (310) 534-3760. Very truly yours, T. A. TIDEMANSON Director of Public Works LATA THAKAR District Engineer, Lomita. cc: TR, EB, BH, THOMAS A. TIDEMANSON. Director COUNTY OF LOS ANGE ,S raryz DEPARTMENT OF PUBLIC WORKS NOV 0 8 1993 900 SOUTH FREMONT AVENUE ALHAMBRA. CALIFORNIA 91803-1331 Telephone: (818) 458-5100 November 4, 1993 Ms. Lola Ungar, Principal Planner City of Rolling Hills 2 Portuguese Bend Road Rolling Hills, CA. 90274 p,, CITY OF ROLLING mullEkbDRrss.aL1.CaaRESP E\CE TO: P.O.BOX 1460 ALHAMBRA. CALIFORNIA 91802-1460 IN REPLY PLEASE REFER TO FILE Dear Ms. Ungar: SURFACE DRAINAGE CONDITIONS AT # 2 RANCHERO ROAD. CITY OF ROLLING HILLS, CA. OWNER: ALFRED A. MARIN References: 1) March 4, 1993 report from Mr. David C. Breiholz, P. E. President, David C. Breiholz And Company, Inc. to Mr. Albert Marin. 2) March 16, 1993 Letter from Mr. Alfred A. Marin to Rolling Hills Community Association, City of Rolling Hills. As requested by you, we have reviewed the above referenced letters, and we have the following comments: 1. As you know the topography of this area is changingdue to an active landslide. This has resulted in diversion of the rain water runoff from the surrounding areas onto the subject property. 2. The Report from Mr. Breiholz recommends to have the drainage conditions improved on and around the subject property in order to protect the lot and extend the life of the house. He suggests to accomplish this by regrading the access road and an adjacent lot, and by replacing the soil on Mr. Marin's lot that was washed away, in order to stabilize the driveway and hardscape areas around the house. Mr. Breiholz is specific in his report, that the owner is not at liberty to do grading work within the boundary of his property without an approved plan and permit, and is not at liberty to perform any off -site work. However, due to the active landslide,the City Building Code does not permit issuance of a building or a grading permit within such area per sec. 308(b). Provisions of the City Building Code do not apply to the work recommended on the access roads owned by the Association. page-1 Ms. Lola Ungar November 4, 1993 Page 2 3. Review of geology maps for Flying Triangle area indicates that an active landslide scarp transects the subject property. This situation along with heavy runoff concentrated at this location last season has eroded the soil supporting the footings of a portion of the garage/guest quarters. 4. About the proposal made by Mr. Marin in his letter, Reference 2 above, to replace the eroded soil by bringing truckloads of fill, our comments in May 24, 1993 letter (copy attached), regarding soil import/export policy within the Flying Triangle Landslide, are still valid and are applicable to the modifications proposed for the subject property. As stated in that letter; sealing of "minor" (3-12± inches) fissures and scarps with earth materials or asphalt for driveways and access roads is desirable to mitigate or lessen infiltration of surface water. 5. Since this lot and the surrounding areas are all within the boundaries of the active landslide area, a permit, under all of the provision of section 308 (b) 3.c of the City Building Code, may be issued for the work involving the alteration or minor repair of existing structures such as a foundation retrofits as required. Upon submittal of the plans and supporting calculations, along with payment of appropriate fees, we will be happy to evaluate them as soon as possible. If we can be of further assistance, please contact the undersigned at (310) 534-3760. Very truly yours, T. A. TIDEMANSON Director of Public Works LATA THAKAR District Engineer, Lomita. cc: TR, EB, BH. COUNTY OF LOS ANGEL• DEPARTMENT OF•PUBLIC WORKS 900 SOUTH FREMONT AVENUE ALHAMIBRA. CALIFORNIA 91303-1331 Telephone: (818) 458-5100 THOMAS A. TIDESIANSON, Director May 24, 1993 Ms. Lola Ungar, Principal Planner City of Rolling,Hills 2 Portuguese Bend Road Rolling Hills, CA. 90274 ADDRESS ALL CORRESPONDENCE TO: P.O. BOX 1460 ALHANIBRA. CALIFORNIA 91802-1460 IN REPLY PLEASE REFER TO FILE: Dear Ms. Ungar: SOIL IMPORT/EXPORT POLICY WITHIN FLYING TRIANGLE LANDSLIDE AREA, CITY OF ROLLING HILLS, CA. References: 1) March 22, 1993 Letter from Mr. Craig R. Nealis, City Manager, City of Rolling Hills, to Honorable Mayor .and Members of the City Council. 2) February 25, 1993 Letter from Ms. Peggy R. Minor, Association Manager, City of Rolling Hills, to Mr. Craig Nealis, City Manager, City of Rolling Hills. In response to your letter of March 25, 1993 regarding the above referenced letters, we are pleased to provide following comments. These comments relate to correction of surface ruptures, i.e. fissures and scarps created by landslide movement within Flying Triangle landslide area. Since this is an active landslide neither the County or the City can predict or provide assurance as to its future behavior even without any modification. 1. Being an active landslide phenomena, it is sensitive to . modification of topography and drainage. As a general rule,` modification of topography and drainage on properties on active landslides, particularly where adjacent properties are affected, is prohibited by the City Building code. 2. No assurances can be provided that importing additional materials or grading of this site will not adversely impact the area or adjacent property. 3. The sealing of "minor" (3-12 + inches) fissures and scarps with earth materials or asphalt for driveways and streets can mitigate or lessen infiltration of surface water. 4. "Major" (several feet high) landslide head scarps and head areas may require several truck loads of earth Ms. Lola Ungar May 24, 1993 Page 2 materials to re-establish access. The weight of these materials could surcharge and decrease the stability of the landslide. Re-establishment of access in this manner involves substantial risks of adversely affecting the stability of the area. 5. Further deterioration of existing improvements should be anticipated, as slide movement and deformation will continue under current landslide conditions. Creation of a Geologic Hazard Abatement District to assess current conditions for possible remedial measures may be warranted. The above comments are based upon evaluation and assessment of the Flying Triangle landslide phenomena by our Materials Engineering Division. If we can be of further assistance, please contact the undersigned at (310) 534-3760. Very truly yours, T. A. TIDEMANSON Director of Public Works LATA THAKAR District Engineer, Lomita. cc: TR, EB, BH, THOMAS A. TIDEMANSON. Director C1RJNTY OF LOS ANGE&S DEPARTMENT OF PUBLIC WORKS 900 SOUTH FREMONT AVENUE ALHAMBRA. CALIFORNIA 91803-1331 Telephone: (818) 458-5100 November 4, 1993 Ms. Lola Ungar, Principal Planner City of Rolling Hills 2 Portuguese Bend Road Rolling Hills, CA. 90274 Dear Ms. Ungar: SURFACE DRAINAGE CONDITIONS AT # 2 RANCHERO ROAD. CITY OF ROLLING HILLS, CA. OWNER: ALFRED A. MARIN March 4, 1993 report from Mr. David C. Breiholz, P. E. President, David C. Breiholz And Company, Inc. to Mr. Albert Marin. March 16, 1993 Letter from Mr. Alfred A. Marin to Rolling Hills Community Association, City of Rolling Hills. you, we have reviewed the above referenced have the following comments: References: 1) 2) As requested by letters, and we gr-4.:(Nawlq NOV 0 8 1993 Eh) ��CITY OF ROLLING HILL$ Eh DRESS -ALL CD&RESEQ ENCE TO: P.O.BOX 1460 ALHAMBRA. CALIFORNIA 91802-1460 IN REPLY PLEASE REFER TO FILE 1. As you know the topography of this area is changing due to an active landslide. This has resulted in diversion of the rain water runoff from the surrounding areas onto the subject property. 2. The Report from Mr. Breiholz recommends to have the drainage conditions improved on and around the subject property in order to protect the lot and extend the life of the house. He suggests to accomplish this by regrading the access road and an adjacent lot, and by replacing the soil on Mr. Marin's lot that was washed away, in order to stabilize the driveway and hardscape areas around the house. Mr. Breiholz is specific in his report, that the owner is not at liberty to do grading work within the boundary of his property without an approved plan and permit, and is not at liberty to perform any off -site work. However, due to the active landslide, the City Building Code does not permit issuance of a building or a grading permit within such area per sec. 308(b). Provisions of the City Building Code do not apply to the work recommended on the access roads owned by the Association. page-1 • • Ms. Lola Ungar November 4, 1993 Page 2 3. Review of geology maps for Flying Triangle area indicates that an active landslide scarp transects the subject property. This situation along with heavy runoff concentrated at this location last season has eroded the soil supporting the footings of a portion of the garage/guest quarters. 4. About the proposal made by Mr. Marin in his letter, Reference 2 above, to replace the eroded soil by bringing truckloads of fill, our comments in May 24, 1993 letter (copy attached), regarding soil import/export policy within the Flying Triangle Landslide, are still valid and are applicable to the modifications proposed for the subject property. As stated in that letter; sealing of "minor" (3-12± inches) fissures and scarps with earth materials or asphalt for driveways and access roads is desirable to mitigate or lessen infiltration of surface water. 5. Since this lot and the surrounding areas are all within the boundaries of the active landslide area, a permit, under all of the provision of section 308 (b) 3.c of the City Building Code, may be issued for the work involving the alteration or minor repair of existing structures such as a foundation retrofits as required. Upon submittal of the plans and supporting calculations, along with payment of appropriate fees, we will be happy to evaluate them as soon as possible. If we can be of further assistance, please contact the undersigned at (310) 534-3760. Very truly yours, T. A. TIDEMANSON Director of Public Works -Lain LATA THAKAR District Engineer, Lomita. cc: TR, EB, BH. COINTY OF LOS ANGELS DEPARTMENT OF PUBLIC WORKS 900 SOUTH FREMONT AVENUE ALHAMBRA. CALIFORNIA 91E03-1331 Telephone: (818) 458.5100 THOMAS A. TIDEMANSON, Director May 24, 1993 Ms. Lola Ungar, Principal Planner City of Rolling,Hills 2 Portuguese Bend Road Rolling Hills, CA. 90274 ADDRESS ALL CORRESPONDENCE TO: P.O. BOX 1460 ALHAMBRA, CALIFORNIA 91802-1460 IN REPLY PLEASE REFER TO FILE: Dear Ms. Ungar: SOIL IMPORT/EXPORT POLICY WITHIN FLYING TRIANGLE LANDSLIDE AREA, CITY OF ROLLING HILLS, CA. References: 1) March 22, 1993 Letter from Mr. Craig R. Nealis, City Manager, City of Rolling Hills, to Honorable Mayor .and Members of the City Council. 2) February 25, 1993 Letter from Ms. Peggy R. Minor, Association Manager, City of Rolling Hills, to Mr. Craig Nealis, City Manager, City of Rolling Hills. In response to your letter of March 25, 1993 regarding the above referenced letters, we are pleased to provide following comments. These comments relate to correction of surface ruptures, i.e. fissures and scarps created by landslide movement within Flying Triangle landslide area. Since this is an active landslide neither the County or the City can predict or provide assurance as to its future behavior even without any modification. 1. Being an active landslide phenomena, it is sensitive to modification of topography and drainage. As a general rule,' modification of topography and drainage on properties on active landslides, particularly where adjacent properties are affected, is prohibited by the City Building code. 2. No assurances can be provided that importing additional materials or grading of this site will not adversely impact the area or adjacent property. 3. The sealing of "minor" (3-12 + inches) fissures and scarps with earth materials or asphalt for driveways and streets can mitigate or lessen infiltration of surface water. 4. "Major" (several feet high) landslide head scarps and head areas may require several truck loads of earth • i Ms. Lola Ungar May 24, 1993 Page 2 materials to re-establish access. The weight of these materials could surcharge and decrease the stability of the landslide. Re-establishment of access in this manner involves substantial risks of adversely affecting the stability of the area. 5. Further deterioration of existing improvements should be anticipated, as slide movement and deformation will continue under current landslide conditions. Creation of a Geologic Hazard Abatement District to assess current conditions for possible remedial measures may be warranted. The above comments are based upon evaluation and assessment of the Flying Triangle landslide phenomena by our Materials Engineering Division. If we can be of further assistance, please contact the undersigned at (310) 534-3760. Very truly yours, T. A. TIDEMANSON Director of Public Works -La LATA THAKAR District Engineer, Lomita. cc: TR, EB, BH, t COISTY OF LOS ANGEL• DEPARTMENT OF PUBLIC WORKS 900 SOUTH FREMONT AVENUE ALHANIBRA, CALIFORNIA 91803-133I Telephone: (818) 458-5100 THOMAS A. TIDEMANSON, Director May 24, 1993 Ms. Lola Ungar, Principal Planner City of Rolling.Hills 2 Portuguese Bend Road Rolling Hills, CA. 90274 ADDRESS ALL CORRESPONDENCE TO: P.O. BOX 1460 ALHAMBRA, CALIFORNIA 91802-1460 IN REPLY PLEASE REFER TO FILE: Dear Ms. Ungar: SOIL IMPORT/EXPORT POLICY WITHIN FLYING TRIANGLE LANDSLIDE AREA, CITY OF ROLLING HILLS, CA. References: 1) March 22, 1993 Letter from Mr. Craig R. Nealis, City Manager, City of Rolling Hills, to Honorable Mayor and Members of the City Council. 2) February 25, 1993 Letter from Ms. Peggy R. Minor, Association Manager, City of Rolling Hills, to Mr. Craig Nealis, City Manager, City of Rolling Hills. In response to your letter of March 25, 1993 regarding the above referenced letters, we are pleased to provide following comments. These comments relate to correction of surface ruptures, i.e. fissures and scarps created by landslide movement within Flying Triangle landslide area. Since this is an active landslide neither the County or the City can predict or provide assurance as to its future behavior even without any modification. 1. Being an active landslide phenomena, it is sensitive to modification of topography and drainage. As a general rule,' modification of topography and drainage on properties on active landslides, particularly where adjacent properties are affected, is prohibited by the City Building code. 2. No assurances can be provided that importing additional materials or grading of this site will not adversely impact the area or adjacent property. 3. The sealing of "minor" (3-12 + inches) fissures and scarps with earth materials or asphalt for driveways and streets can mitigate or lessen infiltration of surface water. 4. "Major" (several feet high) landslide head scarps and head areas may require several truck loads of earth • Ms. Lola Ungar May 24, 1993 Page 2 materials to re-establish access. The weight of these materials could surcharge and decrease the stability of the landslide. Re-establishment of access in this manner involves substantial risks of adversely affecting the stability of the area. 5. Further deterioration of existing improvements should be anticipated, as slide movement and deformation will continue under current landslide conditions. Creation of a Geologic Hazard Abatement District to assess current conditions for possible remedial measures may be warranted. The above comments are based upon evaluation and assessment of the Flying Triangle landslide phenomena by our Materials Engineering Division. If we can be of further assistance, please contact the undersigned at (310) 534-3760. Very truly yours, T. A. TIDEMANSON Director of Public Works } -e3-6 eT;t1e. LATA THAKAR District Engineer, Lomita. cc: TR, EB, BH, • S?of LnL9 hifL'. Community £1.ociaLion of cRaizefio PaLos (Veactes No. 1 PORTUGUESE BEND RD. • ROLLING HILLS, CALIF. 90274 (310) 544-6222 ROLLING HILLS CALIFORNIA TO: LOLA UNGAR, CITY PLANNER FROM: PEGGY MINOR, MANAGER DATE: APRIL 2, 1993 RE: SURFACE DRAINAGE AT 2 RANCHERO ROAD The Board of Directors recently received a letter dated March 16, 1993 sent by Mr. Al Marin to Mr. Craig Nealis, City Manager, relating to surface drainage affecting his property. It is my understanding that the City, through the Los Angeles County Engineer, is reviewing recommendations submitted by Mr. David Breiholz, Civil Engineer. As we discussed today, when the County's report is received, if any . recommendations involve the Rolling Hills Community Association, we will appreciate a copy for the Board's consideration. do Man MAR 1 81993 CITY OF ROLLING HILLS Alfred A. Marin #2 Ranchero Road �'•••--•-------�••-•• Rolling Hills, Ca. 90274 March 16, 1993 Rolling Hills Community Association #2 Portuguese Bend Road Rolling Hills, Ca. 90274 Attention: Mr. Craig Nealis, City Manager Reference: Surface Drainage Conditions at #2 Ranchero Road, Rolling Hills, Ca. Dear Mr. Nealis; On numerous occasions over the past five years I have spoken with both Directors and staff at our Community Association regarding an ongoing problem from drainage of rain water from city streets and adjacent vacant lots running into my driveway, flooding my garage and on one occasion, rain water entered into the house. This year particularly, the runoff eroded more than 20 feet of soil around the foundation of my garage. I have asked the association permission to replace the eroded soil by bringing in truckloads of fill and have been refused. I have now contracted with a registered Civil Engineering firm to observe the condition and report their findings. Perhaps a solution will be worked out before greater damage occurs. A copy of David C. Breiholz and Company's report is attached. Thank you for your consideration in this matter. I have incurred this problem for too many years, the clean-up, the nuisance and cost can no longer be tolerated. Sincerely yours, aqr€A Alfred A. Marin Enc. cc: Gordana Swanson, City Mayor AAM/ls DAVID C. BREIHOLZ AND COMPANY, INC. • Engineering Design Construction 1852 Lomita Boulevard Lomita, Califomia 90717 213 530 3050 FAX: 213 530 0184 March 4, 1993 Mr. Albert Marin #2 Ranchero Road Rolling Hills, CA 90274 RE: Surface Drainage Conditions at #2 Ranchero Road, Rolling Hills, CA Owner: Albert Marin Job No. 93-038E Dear Mr. Marin: In regard to your request of February 16, 1993, I inspected your above referenced property and the adjacent lots and streets with you on Thursday, February 18, 1993. The purpose of the inspection was to observe drainage patterns and conditions that affect runoff to, on and around your lot (Lot 13) at #2 Ranchero Road. My inspection consisted of observing the slope of your driveway, yard areas and the adjacent properties, Lots 6, 7, 8, 12, and 15 as well as the streets, Ranchero Road and Portuguese Bend Road, that serve those lots. The rain started at about 8:30 a.m. as we concluded the inspection. I returned to the site later in the day to check first hand what was fairly obvious earlier under the dry conditions. Following are drainage conditions observed that are detrimental to your property and contribute to potential cosmetic and structural damage: 1) The runoff from Portuguese Bend Road above Ranchero Road does not stay on Portuguese Bend Road but is diverted by land movement and patching/repaving work to Ranchero Road. 2) The runoff from Lot 7, (Barth Lot) drains west to Ranchero Road instead of east or south to Portuguese Bend Road, in spite of sand bags and recent grading to improve sight distance at the street intersection. 3) Lot 6, immediately across and upstream from your property drains across Ranchero Road into and through your driveway. The trenches and sand bags in the easement between Lots 6 and 7 intended to help divert water and mud to Lot 7, were inadequate during the downpour. Civil Engineering Structural Design Seismic Hazard Reduction Construction Supervision Plan Check Service Inspection Service • Page Two March 4, 1993 4) Finally, all the runoff from the above three sources ends up running under your gara a guest quarters, because the low spot of Ranchero Road coincides WiTh your driveway. The driveway is below the road and lacks a gutter or berm at the edge of the pavement along Ranchero Road. The cross gutter at the upper end of the driveway was inundated with mud and even if cleaned out, would be effective only in a light rain because of the large tributary area of runoff your driveway has to deal with. As you are fully aware, your lot and your contiguous neighbors are all within the boundaries of the active landslide area. A great concern to the slide area is control of drainage of the 10 or 12 foundation retrofits our office has performed in the Peninsula slide areas, the geotechnical consultants placed higher priority on the drainage recommendations than the soil condition or foundation system. Ideally all roof lot and street water is collected and conducted in a non -erosive device to a harmless outlet beyond the limits of the active and ancient slide areas. In the case of your particular property, the existing drainage conditions are causing damage to the lot immediately adjacent to the structure at the east side of the garage. The damage consists of the storm flow down the driveway carrying away the soil from around the retrofitted foundations. (During the heavy rain, the runoff from the street was flowing through the breezeway within a few inches of the kitchen floor.) In order to protect your lot and extend the life of your house I recommend you have the drainage conditions improved on and around your property. In spite of the hazardous condition, I realize you are not at liberty to do grading work in your easements or within your property boundaries without an approved plan and permit and not at all off -site, so I recommend you take steps with the City and Homes Association to effect the following: A. Regrade the Barth Lot (Lot 7) or practical portion of the lot either the runoff will drain to Portuguese Bend Road. B. Provide a berm or rolled curb on the western edge of the paving on Portuguese Bend Road to keep the Portuguese Bend Road water on the pavement and prevent it from draining on to Ranchero Road. C. Provide a catch basin within the sand -bagged area on the north side of Ranchero Road. The catch basin should drain under Ranchero Road southerly to the next available drainage swale or drain pipe inlet. D. Replace the soil on your lot that was washed away in order to stabilize the driveway and hardscape areas around the house. Fill slopes created by the new soil should not exceed a slope of 2 to 1. is Page Three • March 4, 1993 • Some of the above work could be done in conjunction with the routine grading and drainage maintenance that occurs in the slide area, i.e., the Portuguese Bend Road berm could be placed the next time asphalt paving work is done in the area. I appreciate the opportunity to be of service, should you have any questions please call me. Very truly yours, C David C. Breiholz, President DCB/jks:93-038E • City ol JUL January 14, 1993 Mr. Alfred A. Marin 2 Ranchero Road Rolling Hills, CA 90274 INCORPORATED JANUARY 24, 1957 NO. 2 PORTUGUESE BEND ROAD ROLLING HILLS, CALIF. 90274 (310) 377-1521 FAX: (310) 377-7288 SUBJECT: REQUEST TO IMPORT SOIL TO 2 RANCHERO ROAD Dear Mr. Marin: Thank you for your letter of December 23, 1992. In your correspondence, you did not state how much soil you wish to import, nor the reason for the request. Therefore, at this time we must deny your request. If you wish to do any grading in the Flying Triangle Landslide Area, a map of which is on file in the offices at City Hall, you will need to provide 4 sets of an Erosion Control Plan prepared by a Certified Civil Engineer, to the satisfaction of the City and the County, which includes the amount of soil (cubic yards) that you wish to import to your property. Feel free to call me at (310) 377-1521 if you have any questions regarding the processing of your request. Thank you for your cooperation. Sincerely, LOLA UNGA PRINCIPAL PLANNER cc: Ms. Peggy Minor, Manager, Rolling Hills Community Association Ms. Lata Thakar, District Engineer, L.A. County Department of Public Works, Lomita Building and Safety Division ®Printed on Recycled Paper. 4"71Q DEC 2 8 1992 Alfred A. Marin CITY OF ROLLING HILLS 2 Ranchero Road BY Rolling Hills, Ca. 90274 December 23- 1992 City Manager City of Holling Hills 2.Portuguese Bend Road Rolling Hills, Ca. 90274 Attention: Mr. Craig Nealis Dear Mr. Nealis; Recently our "Rolling Hills Newsletter" advised homeowners in the "Flying Triangle Area" to fill in any open cracks or fissures that are evident on our property, particularly now, at the onset of our rainy season. By this letter I am requesting permission to import a few truckloads of soil or sand to fill in an area that has been eroding from the rain water that drains onto my property from the runoff of Portuguese Bend Road and Ranchero Road. I can be reached at (213) 756-8113 at my office or (310) 377-6330, at home. Thank you for your consideration. Very truly yours, Alfred A. Marin AAM/ls cc: Mr. Ed Acosta L.A. County Department of Public Works District Engr. Association, Bldg & Safety Div. 24320 S. Narbonne Ave. Lomita, Ca. 90717