HomeMy WebLinkAboutPD 2021-0013; 3367 APPIAN ROAD; GEOTECHNICAL REVIEW OF GRADING PLANS AND COMMENTS FOR MINOR SLOPE FAILURE; 2021-05-05Bruce Blandy
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
485 Corporate Drive, Suite B
Escondido, California 92029
Telephone: (619) 867-0487 Fax: (714) 409-3287
3367 Appian Road
Carlsbad, California 92010
May 5, 2021
P/W 2005-01
Report No. 2005-01-B-3
City Project No. PD2021-0013
Attention:
Subject:
Reference:
Mr. Bruce Blandy
Review of Grading Plans and Comments Related to Grading 011 Slope, Proposed Slope
Failure Repab~ 3367 Appian Road, Carlsbad, California
Advanced Geotechnical Solutions, Inc. (2020). "Limited Geotechnical Investigation of
Minor Slope Failure, 3367 Appian Road, Carlsbad, California," dated July 23, 2020
(Report No. 2005-0l-B-2R).
In accordance with a request by the civil engineer, Advanced Geotechnical Solutions, Inc., (AGS) has
prepared this letter presenting our geotechnical review of the grading plans for the proposed slope repair to
occur at 3367 Appian Road in the City of Carlsbad, California. Also provided are comments related to
grading on the slope. Several different recommendations to repair the slope failure were provided in the
referenced report by AGS . The owner elected to repair the failure at the top of the slope using a soil nail
wall. The owner elected not to reconstruct the slope above El Camino Real.
A grading plan was prepared by BHA, Inc., and shows the proposed repair and drainage improvements.
Also included in the plan set are the soil nail wall plans that were prepared by Geostructural Engineering
Inc. The soil nail and shotcrete wall is shown at the top of the slope where the more significant erosional
scarp is located. The wall is shown to match the inclination of the slope in order to match sunounding
grades and avoid having to grade the area around the wall. Drainage improvements are also shown, which
include the construction of new area drains at the top of the slope and a discharge pipe that is buried in the
slope and discharges via curb outlet drain on El Camino Real..
Based upon our review of the grading and soil nail wall plans and calculations, it is our opinion that the
plans and calculations were prepared in general accordance with the recommendations presented in the
referenced report.
As recommended in Section 7.0, Bullet item 2, of the reference repmt, remedial grading of the slope should
include the removal of failed materials on the slope face . This material was observed to contain a mixture
of vegetation and soil and i.n some cases was sitting atop topsoil and/or vegetation. AGS had recommended
that this material be stripped of the slope face. The limits and depth of the stripping should be determined
during construction by the geotechnical consultant. Care should be taken during removals as to avoid
oversteepening or undermine pmtions of the slope. AGS also recommended the installation of vegetation
on the slope to enhance its stability.
ORANGE AND L.A. COUNTIES
(714) 786-5661
INLAND EMPIRE
(619) 867-0487
SAN DIEGO AND IMPERIAL COUNTIES
(619) 867-0487
May 5, 2021
P/W 2005-01
Page 2
Repmt No. 2005-0 l-B-3
As mentioned in the repmt, the recommended measures were intended to reduce, but not eliminate, the
potential for future surficial failures. Maintenance of the slope is necessary for the long term performance
of the slope.
The recommendations presented in the referenced repmt are based on the assumption that an appropriate
level of field review will be provided by geotechnical consultant during construction.
The opportunity to be of service is sincerely appreciated. If you should have any questions, please do not
hesitate to contact the undersigned.
2005-0 l-B-3 (May 5, 2021, Plan Review and Slope Grading Comments, Blandy Residence).docx
Distribution: (I)
( I)
Addressee (pdt)
Civil Engineer (pdt)
ADVANCED GEOTECHNICAL SOLUTIONS, INC.