Filling for buildings on land where the existing material is satisfactory for foundations, but where the elevation is below the required or desirable elevation for the improvement, shall be in accordance with the following:
(A) Material. Fill material shall be clean sand, sand and rock, pit run limerock and rock fills or other acceptable granular material approved by the Department of Planning and Development Services. Fill material shall be free of all organic and vegetable material, clay, muck and other deleterious substances. Fill material shall not contain rocks or lumps having a diameter of more than four inches. Not more than 8% of the fill material shall pass the 200-mesh sieve.
(B) Existing earth area to be filled. The existing surface on which the fill material is to be placed shall be cleared and grubbed, removing all topsoil, organic and vegetable material, roots and other foreign material. The surface shall then be plowed or scarified to a depth of at least six inches. The existing surface shall then be thoroughly wetted to approach the optimum moisture content and compacted to not less than 90% of maximum density as determined by the AASHO Test No. T-180. The area of the existing surface to be prepared as described above shall be an area whose side dimensions are equal to the side dimensions of the building footing line, plus eight feet, plus three times the height of the fill above the existing grade, as provided in drawing No. F-1-61 adopted by § 151.079. The acceptability of the existing earth material on the land over which the fill material is to be placed shall be approved by the Building Department.
(C) Filling operation and compaction. The fill material shall be placed in uniform layers not to exceed 12 inches in depth measured loose. Each layer shall be spread evenly and uniformly over the entire area and shall be thoroughly mixed during the spreading to insure uniformity of material in each layer. The fill material, while being placed and compacted, shall be thoroughly wetted so that the material will be compacted at or near the optimum moisture content of the material, as determined from the Proctor tests performed by the laboratory. Each layer of material after being placed, mixed and spread shall be thoroughly compacted to a density not less than 95% of AASHO test No. T-180. Compaction shall be by sheepsfoot rollers, multiple wheel pneumatic-tired rollers, mechanical vibrators, or other suitable methods to obtain the specified density. Compaction of each layer or fill shall be continuous over its entire area, and shall be performed while the material is at the specified moisture content.
(D) Height of fill. The entire area of the fill shall be brought up to the design or proposed finished grade elevation at the building line of the proposed building. See drawing No. F-1-61 adopted by § 151.079.
(E) Laboratory control and testing.
(1) A recognized and approved testing laboratory shall exercise control of the fill material and entire filling operation. The following laboratory tests and controls will be required:
(a) Gradation or sieve analysis of fill material.
(b) Proctor compaction test of fill material and of existing earth on which fill material will be placed. Proctor tests shall be in accordance with the AASHO Test No. T-180.
(c) Field density tests of the existing material on which the fill is to be placed, and field density tests of each 12-inch layer of the fill material.
(2) Proctor compaction tests and gradation analysis will be required for each different type of fill material used, and a minimum of at least one Proctor compaction test and gradation analysis shall be made for each six lots or building sites. Field density tests shall be made for each layer of fill placed, and successive layers of fill shall be placed only after density tests indicate the preceding layer has been compacted to the required density. A minimum of one field density test shall be made for each 800 square feet of area or fraction thereof. The requirements for the gradation or sieve analysis of the fill material may be waived at the discretion of the Building Department.
(F) Limits of area to be filled. The area to be filled as described in this section, shall be under all portions of the proposed building or structure, including porches, patios, swimming pools, garages, utility rooms, and the like. Outside floor slabs, such as patios, which have no walls or roofs supported thereon need not be placed on fill as prescribed by this subchapter if approved by the Department of Planning and Development Services; however, such floor slabs, if not placed on fill as prescribed by this subchapter, shall not be structurally connected to the building in any way. See drawing No. F-1-61 adopted by § 151.079.
(G) Inspection and permits.
(1) The entire filling operation shall be subject to the inspection and approval of the Building Department and Engineering Department.
(2) A standard permit shall be obtained from the Department of Planning and Development Services for the filling project, and a permit fee commensurate with the fee requirements of the city building code shall be paid. In the event the filling operation has not been accomplished prior to the submittal of building plans for the building permit, one permit may be issued for the entire project at the fee required for the total cost of the entire project.
(3) Application for the permit for the filling operation shall be accompanied by two sets of drawings showing the following information:
(a) Location and legal description of lands to be filled.
(b) Site plan showing the exact area within the lands that will be filled. Such area shall be dimensioned and definitely located within the lot or property.
(c) Height to which fill will be carried above existing grade.
(d) Description of fill material to be used and source from which material will be obtained.
(e) Brief description of existing earth material over which fill will be placed. The Building Department may require standard soil boring and samples or other supporting evidence of existing material, if the acceptability of the existing earth for foundations is questionable.
(f) Simple foundation plan, showing overall dimensions, of the building to be placed on the fill shall be shown if such information is available at the time.
(4) Building plans submitted for building permit for buildings to be placed on fill previously placed in accordance with this subchapter, shall refer to the permit number and date under which the fill was placed.
(5) Laboratory test results and reports of the gradation and the Proctor compaction of the fill material to be used shall be submitted to and approved by the Department of Planning and Development Services before any fill material is placed. Proctor compaction test results and field density tests results of the prepared existing earth surface, over which the fill is to be placed, shall be submitted to and approved by the Department of Planning and Development Services before any fill material is placed.
(6) An inspection shall be required of the existing area, over which fill is to be placed, after it has been cleared, grubbed, scarified and compacted to required density. No fill material may be placed over the existing ground until the above inspection has been made and the preparation approved. Periodic inspections shall be made during the filling operation. Field density test results, showing the fill layer has been compacted to the required density, must be submitted to and approved by the Department of Planning and Development Services for each layer of fill before the next layer of fill may be placed. A final inspection of the completed fill project must be made and approved by the Department of Planning and Development Services. In the event a relatively large area of land, such as a plat or subdivision or section thereof is to be improved and filled in accordance with this subchapter or §§ 151.100 through 151.110, the city reserves the right, if deemed necessary, to require the developer or builder or contractor or owner to retain the full-time services of a representative of a recognized testing laboratory to supervise and inspect the filling operation and see that this subchapter or §§ 151.100 through 151.110 is complied with.
(H) Dredging. In the event the land is to be filled by hydraulic dredge, certain requirements of this subchapter may be waived only at the discretion of the Chief Building Inspector or City Engineer; provided, however, the dredged fill material conforms with the density required by this subchapter and §§ 151.100 through 151.110.
(‘72 Code, § 10-85) (Ord. 1958, passed - - ; Am. Ord. O- 72-19, passed 2-2-72; Am. Ord. O-2011-15, passed 5-4-11)