Grading Design Manual

APPENDIX A - Guidelines for:

Preliminary Soils Reports
Geotechnical Reports
"As Graded" Soils Reports



  1. Signature and professional registration number of project Geotechnical Engineer (G.E.) or Registered Civil Engineer (R.C.E.);
  2. Job Address.
  3. Location description and/or location index map with north arrow, bar scale, etc.;
  4. Description of site conditions including topography, relief, vegetation index map with north arrow, ban, man-made features, drainage and watershed;
  5. Proposed grading including general scope, amount, special equipment and/or methods if applicable;
  6. Planned construction including type of structure and use, type of construction and foundation/floor system, number of stories.


  1. Scope of work including date of work, investigative methods, logs of exploratory excavations, and real or assumed elevation of exploratory excavations for reference of soil materials and samples to finished grade or footing elevations.
  2. Plan with legend including site limits, terrain features, man-made features, locations of exploratory excavations, soil of formational contacts, proposed improvements (including slopes with ratios, daylight lines, paving areas, retaining/crib walls, subdrains, over-excavation/cleanout/uncompacted fill areas).
  3. Location of all surface and subsurface soil samples collected.
  4. Ground water conditions and potential for future natural or artificial seepages.


  1. Test methods used, type or condition of samples, applicable engineering graphics, results of all tests, and locations of all test samples.
  2. Unified soil classification of materials.
  3. Material competency and strength
    1. Field densities and moisture content, as well as relative compactions where pertinent.
    2. Shear strength parameters of foundation material (drained or undrained conditions, effective stress or total stress analysis). In-situ or remolded samples must be identified.
    3. Consolidation or settlement potential.
  4. Maximum dry density/optimum moisture parameters as determined by ASTM D1557-78.

(Contact Building Department for additional requirements.)

  1. Footing depth, width, design and placement;
  2. Criteria for foundation material preparation;
  3. Allowable bearing values based on testing;
  4. Lateral pressures (active, passive, or at-rest conditions) and coefficient or friction;
  5. Settlement - total, differential and rate of settlement;
  6. Footing design and placement criteria;


All general and site-specific materials reviewed in conjunction with the report preparation should be referenced in the report.


  1. Ground preparation, including recommendations regarding clearing unsuitable material removal, scarification and moisture conditioning.
  2. Suitability of in-situ soil materials to support fill and/or structures. Describe requirements to be used to determine soil suitability. Also describe densification and moisturization or dewatering measures, including equipment, surcharge, settlement monitoring, etc., as appropriate.
  3. Placement of structural fill:
    1. Suitability of on site and imported soils for use in compacted fill.
    2. Methods of ASTM standards to be used in fill compaction.
    3. Testing methods and procedures to be used, including frequency of field density testing b vertical intervals and/or volume of fill.
    4. Minimum recommended percent relative compaction for mass graded fill soils.
  4. Recommendations for treatment of cut/fill lines or other differential transitions beneath improvements.
  5. Backfill specifications and specific recommendations for compaction of utility trenches, slope faces, landscape areas, and other structural and nonstructural areas.
  6. Provisions for final observations and necessary testing during and subsequent to grading.
  7. Assessment as to the adequacy of the site for the proposed development.
  8. Any other geotechnical information pertinent to the development of the site.



A geotechnical soils report shall include the following information and any additional information or investigation required by the City Engineer.


  1. Signature and professional number of the Certified Engineering Geologist (C.E.G.) under which the work was performed, date report was signed, company name, mailing address and phone number.
  2. The Tentative Map number, street address or any information to help locate the project area, as available.
  3. Site description, which should include comments addressing the following:
    1. Topography vegetation and size of the subject area.
    2. General setting with respect to geologic, geomorphic and geographic features present in the surrounding area.
    3. Location map and site map with scale and north arrow.
    4. Location and condition of any existing structures and/or improvements, including drainage controls.
    5. Purpose of the report, i.e., development proposed (including the proposed land use), sale of real estate, required by City Engineer, etc.
  4. A review of pertinent site specific and general geotechnical literature should be performed, as should a review of site specific aerial photographs. A listing of references reviewed should be included with the report.

Geologic map (when applicable) should be on a topographic base and should include:

  1. Location map,bar scale, north arrow, legend, any geographic features which can be identified in the field, etc.;
  2. Geographic features that may be present such as; formational contacts, faults, folds, anticlines, synclines, domes, joints, fractures, lineaments, terraces, etc. The accompanying report should include an evaluation of how these features may impact the anticipated use;
  3. General limited of existing fields, as indicated by visual observation.

Field investigation should address significant factors which could affect the site. Items to consider are the following:

  1. Geologic description of all units observed on the site.
  2. Relative age, and correlation with named formations.
  3. Attitudes and distribution of the units as they are exposed in the area (not necessarily confined to the report area if significant geologic features are present nearby).
  4. Structural features affecting the report area.
  5. Surficial (unconsolidated) deposits, both artificial and naturals. Distribution, relative age, identification and description of these units.
  6. Landslides and related features.
  7. Sufficient geologic mapping of the area to comment on anticipated ground water conditions that may affect the sit and/or project.
  8. Location of any observed seeps or springs.
  9. Effects of grading on infiltration of water into cut and fill areas.
  10. Discussion of the effects of possible subsurface flow along the natural drainage courses proposed for filling.

The observed conditions should be stated and a general overview of the site geology as it correlates to the feasibility of the proposed project should be presented. An assessment of the degree of hazard present, based on existing information, should be given. If there are suspected geologic problems that cannot be evaluated except through in depth investigation, then this should be clearly stated in the report. No engineering design recommendations for the proposed development should appear in this type of report. Please note that if the geological reconnaissance report recommends further investigation, the recommended investigation must be performed before the City will accept the report.



In addition to the Preliminary Report, as As-Graded Soils Report is always required for hillside grading. It shall be the responsibility of the Civil Engineer who prepares the grading plans to incorporate all recommendations of the preliminary report into the grading plans. The Civil Engineer shall also be responsible for the preparations of revised grading plans and for as-graded grading plans upon completion of the work. Further, the Civil Engineer shall have the responsibility for certifying the finished grading with respect to line and grade.

Grading operations undertaken pursuant to the approved grading plan shall be subject to geotechnical observation and testing by the Geotechnical Engineer or a Registered Civil Engineer and, when geologic conditions so dictate, by a Certified Geologist, who shall have the responsibility to report whether, in their professional opinion, the grading operations were performed in compliance with the geotechnical requirements of the grading plans and specification. After completion of the grading operations, the Registered Civil Engineer or Geotechnical Engineer and/or Engineering Geologist shall submit his reports, compaction test data, and the geotechnical engineering/geology recommendations of the Civil Engineer in the form of As-Graded report. The report shall include the following information:


  1. Signature(s) and professional number (s) of person of the same level of registration or certification as the parties signing the preliminary report.
  2. Job address, lot and map number.
  3. Grading plan number.


  1. Purpose for which fill was place.
  2. Preparation of natural grade to receive fill.
  3. Placement of fill (depth of fill, watering, etc.).
  4. Equipment used for compaction.
  5. Method of compaction for outer slope area.


  1. Test procedure (field and laboratory).
  2. Plot plan graphically depicting the location of all density tests. The plan should be of sufficient size to be reviewable.
  3. Summary of test results:
    1. Test identification number;
    2. Date test performed;
    3. Maximum dry density test;
    4. Optimum moisture;
    5. Field dry density;
    6. Field moisture;
    7. Relative compaction;
    8. Approximate elevation of test;
    9. Approximate finish grade elevation at test site.


  1. Location of test;
  2. Depth of test;
  3. Method of backfill compaction equipment;
  4. Summary of test results.


  1. Summary of expansion test results (identify lots or areas with swelling potential);
  2. Summary of chemical test results, as required;
  3. Summary of corrosion test results, as required.
  4. Fertility reports: Results of agricultural suitability and fertility analysis to support plant life. (for slope areas only)


  1. Plot plan showing limits of the compacted area (approximate pad elevation, depth of fill, areas of over-excavation, keys and subdrains). If slope failures occurred during construction, the limits of these failed areas should be shown on the plan;
  2. Treatment of "daylight" or cut/fill transition zones (extent of over-excavation outside of footing);
  3. Type of soil encountered during grading (fill, in-situ, imported borrow);
  4. Ground water conditions identified and subdrains or other methods used to mitigate adverse effects.
  5. Geologic conditions encountered, including geologic contacts, structural attitudes, marker beds, faults, and bedding plan shears. Geologic data should be included in areas mapped as fill and in buttress excavations;
  6. Comments on changes made during grading and their effect on the recommendations and in the geotechnical report;
  7. Exploratory borings and trenches performed during grading should be located on the maps attached to the report, and logs of these excavations should be included in the report;
  8. Locations of instrumentation at the site, including settlement monuments, extensometers, piezometers, inclinometer, etc., should be plotted on the maps attached to the report. Results of instrument readings should be included in the report;
  9. Elevations at the bottoms of cleanouts, keyways, or other excavations.


  1. Footing recommendations and bearing value on compacted fill;
  2. Footing and floor slab recommendations (Contact Buidling Department for their requirements);
  3. Statement as to the suitability of natural soil to support the fill or structure;
  4. Statement as to the adequacy of the sit for the intended use,, as affected by soil engendering and/or geologic factors;
  5. Statement as to the gross and surficial stability of all slopes. Cross sections prepared during grading for stability calculations should be included in the report, as well as a description of the calculations method, summary of calculation results, and conclusions;
  6. A statement addressing whether the soil engineering and engineering geologic aspects of the grading are in compliance with the applicable conditions of the grading permit and the geotechnical engineer's and engineering geologist's recommendations;
  7. Statement as to the plant life over the slopes.
  8. Statement as to the approval and the field inspection during the construction of all crib walls, and the stability of overall slopes with the crib wall in place.

All grading operations for which a permit is required shall be subject to periodic inspection by the City Engineer. The City engineer shall inspect the project at the various stages of work requiring approval and at more frequent intervals as necessary to determine that adequate control of the earthwork operations is being provided by the Geotehcnical Engineer/Engineering Geologist.

If, in the course of fulfilling their responsibilities under Title 17.06, the Geotechnical Engineer/Engineering geologist or the civil Engineer find that the grading work is not being done in conformance with the approved grading plans, discrepancies shall be reported immediately in writing to the owner, the contractor and the City Engineer. Recommendations by the Geotechnical Engineer/Engineering Geologist for corrective measures, along with a report of findings, shall be submitted as construction change drawings to the owner and to the City Engineer. All changes from the originally approved grading plan shall be reflected in the As-Graded Report and on the As-Graded Grading Plan.