§ 18.70

The purpose of this chapter is to safeguard life, limb, property and public welfare by regulating grading on private property.

(Ord. No. 4333, § 5, 3-17-2015)

This chapter sets forth rules and regulation to control excavation, grading and earthwork construction, including fills and embankments; establishes the administrative procedures for issuance of permits; and provides for approval of the plans and inspection of grading construction.

(Ord. No. 4333, § 5, 3-17-2015)

This chapter regulates grading in the absence of regulations mandated by the State of California. The State Department of Housing and Community Development has adopted Appendix J of the California Building Code, which mandates use of that regulation by all jurisdictions in the State of California for regulating all grading associated with construction of subdivisions or building pads for motels, hotels, lodgings, apartments, dwellings, dormitories, condominiums, homeless shelters, congregate residences, employee housing, factory built housing and other types of dwelling units. This chapter regulates grading activities for areas not regulated by Appendix J.

(Ord. No. 4333, § 5, 3-17-2015)

Section 20.308 of the Mendocino County Code (Mendocino County Coastal Zoning Code) defines "grading" within the coastal zone as any excavation or filling or combination thereof involving transfer of more than two (2) cubic yards of material. Within that same section, "development" is defined as a term that includes grading. Section 20.532.010 of the Mendocino County Coastal Zoning Code states, in part, that any development shall be required to secure a coastal development permit, with certain exemptions

provided in section 20.532.020. As such, grading activities within the County's coastal zone generally require a Coastal Development Permit. Although a grading permit may not be required for activities within the coastal zone as exempted by 18.70.030(b), a coastal development permit may still be required. In addition to consistency with this chapter, grading activity within the coastal zone must also be consistent with Chapter 20.492 of the Mendocino County Code (Grading, Erosion, and Runoff) and Chapter 16.30 of the Mendocino County Code (Stormwater Runoff Pollution Prevention Procedure).

(Ord. No. 4333, § 5, 3-17-2015)

Grading activities may be regulated under state and local provisions of the Surface Mining and Reclamation Act (SMARA). Mendocino County Code applicable to Surface Mining and Reclamation is contained within Chapter 22.16

(Ord. No. 4333, § 5, 3-17-2015)

(A)

Permits Required. Except as specified in Subsection (b) of this section, no person shall do any grading without first having obtained a grading permit from the building official.

(B)

Exempted Work. A grading permit is not required for the following:

(1)

When approved by the building official, grading in an isolated, self-contained area if there is no danger to private or public property.

(2)

An excavation below finished grade for basements and footings of a building, retaining wall or other structures authorized by a valid building permit. This shall not exempt any fill made with the material from such excavation or exempt any excavation having an unsupported height greater than five (5) feet after the completion of such structure.

(3)

Cemetery graves.

(4)

Refuse disposal sites controlled by other regulations.

(5)

Excavations for wells or tunnels or utilities.

(6)

Mining, quarrying, excavation, processing, stockpiling of rock, sand, gravel, aggregate or clay where established and provided for by law, provided such operations do not affect the lateral support or increase the stresses in or pressure upon any adjacent or contiguous property.

(7)

Exploratory excavations under the direction of soil engineers or engineering geologists.

(8)

An excavation which:

(1)

Is less than two (2) feet in depth, or

(2)

Which does not create a cut slope greater than five (5) feet in height and steeper than one and one-half (1½) horizontal to one (1) vertical.

(9)

A fill less than one (1) foot in depth and placed on natural terrain with a slope flatter than five (5) horizontal to one (1) vertical, or less than three (3) feet in depth, not intended to support structures, which does not exceed fifty (50) cubic yards on any one (1) lot and does not obstruct a drainage course.

Exemption from the permit requirements of this chapter shall not be deemed to grant authorization for any work to be done in any manner in violation of the provisions of this chapter or any other laws or ordinances of this jurisdiction. In particular, exemption from a grading permit does not relieve the requirements to comply with Chapter 16.30 of the Mendocino County Code (Stormwater Runoff Pollution Prevention Procedure), the requirement to comply with Chapter 22.12 of the Mendocino County Code (Archaeological Resources), the requirement to obtain a Coastal Development Permit for eligible activities within the County's Coastal Zone, or the requirement to obtain a construction general permit from the State for grading projects over one acre.

(Ord. No. 4333, § 5, 3-17-2015)

Whenever the building official determines that any existing excavation or embankment or fill on private property has become a hazard to life and limb, or endangers property, or adversely affects the safety, use or stability of a public way or drainage channel, the owner of the property upon which the excavation or fill is located, or other person or agent in control of said property, upon receipt of notice in writing from the building official, shall within the period specified therein repair or eliminate such excavation or embankment so as to eliminate the hazard and be in conformance with the requirements of this chapter.

(Ord. No. 4333, § 5, 3-17-2015)

For the purposes of this chapter the definitions listed hereunder shall be construed as specified in this section.

APPROVAL shall mean the proposed work or completed work conforms to this chapter in the opinion of the building official.

AS-GRADED is the extent of surface conditions on completion of grading.

BEDROCK is in-place solid rock.

BENCH is a relatively level step excavation into earth material on which fill is to be placed.

BORROW is earth material acquired from an off-site location for use in grading on a site.

CIVIL ENGINEER is a professional engineer registered in the state to practice in the field of civil works.

CIVIL ENGINEERING is the application of the knowledge of the forces of nature, principles of mechanics, and the properties of materials to the evaluation, design and construction of civil works.

COMPACTION is the densification of a fill by mechanical means.

EARTH MATERIAL is any rock, natural soil or fill or any combination thereof.

ENGINEERING GEOLOGIST is a geologist experienced and knowledgeable in engineering geology.

ENGINEERING GEOLOGY is the application of geologic knowledge and principles in the investigation and evaluation of naturally occurring rock and soil for use in the design of civil works.

EROSION is the wearing away of the ground surface as a result of the movement of wind, water or ice.

EXCAVATION is the mechanical removal of earth material.

FILL is a deposit of earth material placed by artificial means.

GEOTECHNICAL ENGINEER See "soils engineer"

GRADE is the vertical location of the ground surface.

EXISTING GRADE is the grade prior to grading.

ROUGH GRADE is the stage at which the grade approximately conforms to the approved plan.

FINISH GRADE is the final grade of the site which conforms to the approved plan.

GRADING is any excavating or filling or combination thereof.

KEY is a designed compacted fill placed in a trench excavated in earth material beneath the toe of a proposed fill slope.

PROFESSIONAL INSPECTION is the inspection required by this chapter to be performed by civil engineer, soils engineer or engineering geologist. Such inspections include that performed by persons supervised by such engineers or geologists and shall sufficient to form an opinion relating to the conduct of the work.

SITE is any lot or parcel of land or contiguous combination thereof, under the same ownership, where grading is performed or permitted.

SLOPE is an inclined ground surface the inclination of which is expressed as a ratio of horizontal distance to vertical distance.

SOIL is naturally occurring superficial deposits overlying bedrock.

SOILS ENGINEER (GEOTECHNICAL ENGINEER) is an engineer experienced and knowledgeable in the practice of soils engineering (geotechnical) engineering.

SOILS ENGINEERING (GEOTECHNICAL ENGINEERING) is the application of the principles of the soils mechanics in the investigation, evaluation and design of civil works involving the use of earth materials and the inspection or testing of the construction thereof.

TERRACE is a relatively level step constructed in the face of a graded slope surface for drainage and maintenance purposes.

(Ord. No. 4333, § 5, 3-17-2015)

(A)

Permits Required. Except as in Section 18.70.030(b) of this chapter, no person shall do any grading without first obtaining a grading permit from the building official. A separate permit shall be obtained for each site, and may cover both excavations and fills.

(B)

Application. The provisions of Section 105.3 of the 2013 California Building Code are applicable to grading and in addition the application shall state the estimated quantities of work involved.

(C)

Grading Designation. Grading in excess of five thousand (5,000) cubic yards shall be performed in accordance with the approved grading plan prepared by a civil engineer, and shall be designated as "engineered grading." Grading involving less than five thousand (5,000) cubic yards shall be designated

"regular grading" unless the permittee chooses to have the grading performed as engineered grading, or the building official determines that special conditions or unusual hazards exist, in which case grading shall conform to the requirements for engineered grading.

(D)

Engineered Grading Requirements. Application for a grading permit shall be accompanied by two (2) sets of plans and specifications, and supporting data consisting of a soils engineering report and engineering

geology report. The plans and specifications shall be prepared and signed by an individual licensed by the state to prepare such plans or specifications when required by the building official.

Specifications shall contain information covering construction and material requirements.

Plans shall be drawn to scale upon substantial paper or cloth and shall be of sufficient clarity to indicate the nature and extent of the work proposed and show in detail that they will conform to the provisions of this chapter and all relevant laws, ordinances, rules and regulations. The first sheet of each set of plans shall give location of the work, the name and address of the owner and the person by whom they were prepared.

The plans shall include the following information:

(1)

General vicinity of the proposed site.

(2)

Property limits and accurate contours of existing ground and details of terrain and area drainage.

(3)

Limiting dimensions, elevations or finish contours to be achieved by the grading, and proposed drainage channels and related construction.

(4)

Detailed plans of all surface and subsurface drainage devices, walls, cribbing, dams and other protective devices to be constructed with, or as a part of, the proposed work together with a map showing the drainage area and the estimated runoff of the area served by any drains.

(5)

Location of any buildings or structures on the property where the work is to be performed and the location of any buildings or structures on land of adjacent owners which are within fifteen (15) feet of the property or which may be affected by the proposed grading operations.

(6)

Recommendations included in the soils engineering report and the engineering geology report shall be incorporated in the grading plans or specifications. When approved by the building official, specific recommendations contained in the soils engineering report and the engineering geology reports, which are applicable to grading, may be included by reference.

(7)

The dates of the soils engineering and engineering geology reports together with the names, addresses and phone numbers of the firms or individuals who prepared the reports.

(E)

Soils Engineering Report. The soils engineering report required by Subsection (d) shall include data regarding the nature, distribution and strength of existing soils, conclusions and recommendations for grading procedures and design criteria for corrective measures, including buttress fills, when necessary, and opinion on adequacy for the intended use of sites to be developed by the proposed grading as affected by soils engineering factors, including the stability of slopes.

(F)

Engineering Geology Report. The engineering geology report required by Subsection (d) shall include an adequate description of the geology of the site, conclusions and recommendations regarding the effect of the geologic conditions on the proposed development, and opinion on the adequacy for the intended use of sites to be developed by the proposed grading, as affected by geologic factors.

(G)

Regular Grading Requirements. Each application for a grading permit shall be accompanied by a plan in sufficient clarity to indicate the nature and extent of the work. The plans shall give the location of the work, the name of the owner and the name of the person who prepared the plan.

The plan shall include the following information:

(1)

General vicinity of the proposed site.

(2)

Limiting dimensions and depth of cut and fill.

(3)

Location of any building or structures where work is to be performed, and the location of any buildings or structures within fifteen (15) feet of the proposed grading.

(H)

Issuance. The provisions of Section 105.4 of the 2013 California Building Code are applicable to grading permits. The building official may require that grading operations and project designs be modified if delays occur which incur weather-generated problems not considered at the time the permit was issued.

The building official may require professional inspection and testing by the soils engineer. When the building official has cause to believe that geologic factors may be involved, the grading will be required to conform to engineer grading.

(Ord. No. 4333, § 5, 3-17-2015)

Fees shall be as adopted by resolution by the Board of Supervisors.

(Ord. No. 4333, § 5, 3-17-2015)

The building official may require bonds in such form and amounts as may be deemed necessary to assure that the work, if not completed in accordance with the approved plans and specifications, will be corrected to eliminate hazardous conditions.

In lieu of a surety bond that applicant may file a cash bond or instrument of credit with the building official in an amount equal to that which would be required in the surety bond.

(Ord. No. 4333, § 5, 3-17-2015)

(A)

General. Unless otherwise recommended in the approved soils engineering or engineering geology report, cuts shall conform to the provisions of this section.

In the absence of an approved soils engineering report, these provisions may be waived for minor cuts not intended to support structures.

(B)

Slope. The slope of cut surfaces shall be no steeper than is safe for the intended use and shall be no steeper than two (2) horizontal to one (1) vertical unless the permittee furnishes a soils engineering or an engineering geology report, or both, stating that the site has been investigated and giving an opinion that a cut at a steeper slope will be stable and not create a hazard to public or private property.

(Ord. No. 4333, § 5, 3-17-2015)

(A)

General. Unless otherwise recommended in the approved soils engineering report, fills shall conform to the provisions of this section.

In the absence of an approved soils engineering report, these provisions may be waived for minor fills not intended to support structures.

(B)

Preparation of Ground. Fill slopes shall not be constructed on natural slopes steeper than two to one (2:1). The ground surface shall be prepared to receive fill by removing vegetation, noncomplying fill, topsoil and other unsuitable materials scarifying to provide a bond with the new fill and, where slopes are steeper that five to one (5:1) and the height is greater than five (5) feet, by benching into sound bedrock or other competent material as determined by the soils engineer. The bench under the toe of a fill on a slope steeper than five to one (5:1) shall be at least ten (10) feet wide. The area beyond the toe of fill shall be sloped for

sheet overflow or a paved drain shall be provided. When fill is to be placed over a cut, the bench under the toe of fill shall be at least ten (10) feet wide but the cut shall be made before placing the fill and acceptance by the soil engineer or engineering geologist or both as a suitable foundation for fill.

(C)

Fill Material. Detrimental amounts of organic material shall not be permitted in fills. Except as permitted by the building official, no rock or similar irreducible material with a maximum dimension greater than twelve (12) inches shall be buried or placed in fills.

EXCEPTION: The building official may permit placement of larger rock when the soils engineer property devises a method of placement, and continuously inspects its placement and approves the fill stability. The following conditions shall also apply:

(1)

Prior to issuance of the grading permit, potential rock disposal areas shall be delineated on the grading plan.

(2)

Rock sizes greater than twelve (12) inches in maximum dimension shall be ten (10) feet or more below the grade, measured vertically.

(3)

Rocks shall be placed so as to assure filling of all voids with well-graded soil.

(D)

Compaction. All fills shall be compacted to a minimum of ninety (90) percent of maximum density.

(E)

Slope. The slope of fill surfaces shall be no steeper than is safe for the intended use. Fill slopes shall be no steeper than two (2) horizontal to one (1) vertical.

(Ord. No. 4333, § 5, 3-17-2015)

(A)

General. Cut and fill slopes shall be set back from the site boundaries in accordance with this section. Setback dimensions shall be horizontal distances measured perpendicular to the site boundary.

(B)

Toe of Cut Slope. The toe of cut slopes shall not be made nearer to a site boundary line that one-fifth ( ⅕ ) of the vertical height of cut with a minimum of two (2) feet and a maximum of ten (10) feet. The setback may need to be increased for any required interceptor drains.

(C)

Top of Fill Slope. The toe of fill slope shall be made not nearer to the site boundary line that one-half (½) the height of the slope with a minimum of two (2) feet and a maximum of twenty (20) feet. Where a fill slope is to be located near the site boundary and the adjacent off-site property is developed, special precautions shall be incorporated in the work as the building official deems necessary to protect the adjoining property from damage as a result of such grading. These precautions may include by are not limited to:

(1)

Additional setbacks.

(2)

Provision for retaining or slough walls.

(3)

Mechanical or chemical treatment of the fill slope surface to minimize erosion.

(4)

Provisions for the control of surface waters.

(D)

Modification of Slope Location. The building official may approve alternate setbacks. The building official may require an investigation and recommendation by a qualified engineer or engineering geologist to demonstrate that the intent of the section had been satisfied.

(Ord. No. 4333, § 5, 3-17-2015)

(A)

General. Unless otherwise indicated on the approved grading plan, drainage facilities and terracing shall conform to the provisions of this section for cut or fill slopes steeper than three (3) horizontal to one (1) vertical.

(B)

Terrace. Terraces at least six (6) feet in width shall be established at not more than thirty (30) foot vertical intervals on all cut or fill slopes to control surface drainage and debris except that where only one (1) terrace is required, it shall be at mid-height. For cut or fill slopes greater than sixty (60) feet and up to one hundred twenty (120) feet in vertical height, one (1) terrace at approximately mid-height shall be twelve (12) feet in width. Terrace widths and spacing for cut and fill slopes greater than one hundred twenty (120) feet in height shall be designed by the civil engineer and approved by the building official. Suitable access shall be provided to permit proper cleaning and maintenance.

Swales or ditches on terraces shall have a minimum gradient of five (5) percent and must by paved with reinforced concrete not less than three (3) inches in thickness or an approved equal paving. They shall have a minimum depth at the deepest point of one (1) foot and a minimum paved width of five (5) feet.

A single run of swale or ditch shall not collect runoff from a tributary area exceeding thirteen thousand five hundred (13,500) square feet (projected) without discharging into a down drain.

(C)

Subsurface Drainage. Cut and fill slopes shall be provided with subsurface drainage as necessary for stability.

(D)

Disposal. All drainage facilities shall be designed to carry waters to the nearest practicable drainage way approved by the building official or other appropriate jurisdiction as a safe place to deposit such waters. Erosion of ground in the area of discharge shall be prevented by installation of non-erosive down-drains or other devices.

Building pads shall have a drainage gradient of two (2) percent toward approved drainage facilities, unless waived by the building official.

EXCEPTION: The gradient from the building pad may be one (1) percent if all of the following conditions exist throughout the permit area:

(1)

No proposed fills are greater than ten (10) feet in maximum depth.

(2)

No proposed finish cut or fill slope faces have a vertical height in excess of ten (10) feet.

(3)

No existing slope faces, which have a slope face steeper than ten (10) horizontal to one (1) vertical, have a vertical height in excess of ten (10) feet.

(E)

Interceptor Drains. Paved interceptor drains shall be installed along the top of all cut slopes where the tributary drainage area above slopes toward the cut and has a drainage path greater than forty (40) feet measured horizontally. Interceptor drains shall be paved with a minimum of three (3) inches of concrete or gunite and reinforced. They shall have a minimum depth of twelve (12) inches and a minimum paved width of thirty (30) inches measured horizontally across the drain. The slope of drain shall be approved by the building official.

ard the cut and has a drainage path greater than forty (40) feet measured horizontally. Interceptor drains shall be paved with a minimum of three (3) inches of concrete or gunite and reinforced. They shall have a minimum depth of twelve (12) inches and a minimum paved width of thirty (30) inches measured horizontally across the drain. The slope of drain shall be approved by the building official.

(Ord. No. 4333, § 5, 3-17-2015)

(A)

Slopes. The faces of cut and fill slopes shall be prepared and maintained to control against erosion. This control may consist of effective planting. The protection for the slopes shall be installed as soon as practicable and prior to calling for a final approval. Where cut slopes are not subject to erosion due to the erosion-resistant character of the materials, such protection may be omitted.

(B)

Other Devices. Where necessary, check dams, cribbing, riprap or other devices or methods shall be employed to control erosion and provide safety.

(Ord. No. 4333, § 5, 3-17-2015)

(A)

General. Grading operations for which a permit is required shall be subject to inspection by the building official. Professional inspection of grading operations shall be provided by the civil engineer and the engineering geologist retained to provide such services in accordance with Section 18.70.140(e) for engineered grading and as required by the building official for regular grading.

(B)

Civil Engineer. The civil engineer shall provide professional inspection within such engineer's area of technical specialty, which shall consist of observation and review as to the establishment of line, grade and surface drainage of the development area. If revised plans are required during the course of the work they shall be prepared by the civil engineer.

(C)

Soils Engineer. The soils engineer shall provide professional inspection within such engineer's area of technical specialty, which shall include observation during grading and testing for required compaction. The soils engineer shall provide sufficient observation during the preparation of the natural ground and placement and compaction of the fill to verify that such work is being performed in accordance with the conditions of the approved plan and the appropriate requirements of this chapter. Revised recommendations relating to conditions differing from the approved soils engineering and engineering geology reports shall be submitted to the permittee, the building official and the civil engineer.

(D)

Engineering Geologist. The engineering geologist shall provide professional inspection within such engineer's area of technical specialty, which shall include professional inspection of the bedrock excavation to determine if conditions encountered are in conformance with the approved report. Revised recommendations relating to conditions differing from approved engineering geology report shall be submitted to the soils engineer.

(E)

Permittee. The permittee shall be responsible for the work to be performed in accordance with the approved plans and specifications and in conformance with the provisions of this chapter, and the permittee shall engage consultants, if required, to provide professional inspections on a timely basis. The permittee shall act as a coordinator between the consultants, the contractor and the building official. In the event of changed conditions, the permittee shall be responsible for informing the building official of such change and shall provide revised plans for approval.

(F)

Building Official. The building official shall inspect the project at the various stages of work requiring approval to determine that adequate control is being exercised by the professional consultants.

(G)

Notification of Noncompliance. If, in the course of fulfilling their respective duties under chapter, the civil engineer or the engineering geologist finds that the work is not being done in conformance with this chapter or the approved grading plans, the discrepancies shall be reported immediately in writing to the permittee and to the building official.

(H)

Transfer of Responsibility. If the civil engineer, the soils engineer, or the engineering geologist of record is changed during grading, the work shall be stopped until the replacement has agreed in writing to accept their responsibility within the area of technical competence for approval upon completion of the work.

It shall be the duty of the permittee to notify the building official in writing of such change prior to the recommencement of such grading.

(Ord. No. 4333, § 5, 3-17-2015)

(A)

Final Reports. Upon completion of the rough grading work and at the final completion of the work, the following reports and drawings and supplements thereto are required for engineered grading or when professional inspection is performed for regular grading, as applicable.

(1)

An as-built grading plan prepared by civil engineer retained to provide such services in accordance with Section 18.70.140(e) showing original ground surface elevations, as-graded ground surface elevations, lot drainage patterns, and the locations and elevations of surface drainage facilities and of the outlets of subsurface drains. As-constructed locations, elevations and details of subsurface drains shall be shown as reported by the soils engineer.

Civil engineers shall state that to the best of their knowledge the work within their area of responsibility was done in accordance with the final approved grading plan.

(2)

A report prepared by the soils engineer retained to provide such services in accordance with Section 18.70.140(e), including locations and elevations of field density tests, summaries of field and laboratory tests, other substantiating data, and comments on any changes made during grading and their effect on the recommendations made in the approved soils engineering investigation report. Soils engineers shall submit a statement that, to the best of their knowledge, the work within their area of responsibilities is in accordance with the approved soils engineering report and applicable provisions of this chapter.

(3)

A report prepared by the engineering geologist retained to provide such services in accordance with Section 18.70.140(e), including a final description of the geology of the site and any new information disclosed during the grading and the effect of same on recommendation incorporated in the approved grading plan. Engineering geologists shall submit a statement that, to the best of their knowledge, the work within their area of responsibility is in accordance with the approved engineering geologist report and applicable provisions of this chapter.

(4)

The grading contractor shall submit in a form prescribed by the building official a statement of conformance to said as-built plan and the specifications.

(B)

Notification of Completion. The permittee shall notify the building official when the grading operation is ready for final inspection. Final approval shall not be given until all work, including installation of all drainage facilities and their protective devices, and all erosion-control measures have been completed in accordance with the final approved grading plan, and the required reports have been submitted.

(Ord. No. 4333, § 5, 3-17-2015)