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3-4.5 To the extent possible, cuts and fills should be planned and executed such that the volume of cut soils roughly
equals the required fill for low spots, tank berms, and roadways.
If the area to be utilized is fairly flat and requires only minimal grading, the materials for roadways and tank berms can
come from a borrow pit near the site which can, if desired, be converted to a reserve water storage basin.
3-4.6 In preparing the grading plan and executing the cut and fill, it should be kept in mind that the major equipment,
most particularly the 5000 Bbl tanks, should be set on virgin or cut soils, if possible, rather than on fill.
3-4.7 If it is required that tankage be located on a filled area, the fill must be compacted as it is placed. Compaction
after a deep fill has little effect.
3-4.8 When extensive fill is required, the slopes must be such as to prevent slides and minimize erosion. As a general
rule, there should be no slopes greater than 2:1 (approx. 250) in sandy or loamy soils.
3-5
Roadways
Roadways must be fully compacted, have good drainage, and to the extent possible, have at least a surface of gravel or
crushed rock. Each side of the road should have an adequate swale or ditch to provide good drainage. Drainage
culverts should be placed as required. The road, swale, ditch, and drain culvert requirements will vary with site
conditions and anticipated rainfall. Fig. 2-2 shows a desirable road layout. Roadways must be constructed to permit
ready access to all areas for installation, operation, fuel loading and unloading, and fire fighting.
3-6
Tank Pad and Berm Construction
Proper tank pad and berm construction is most important to provide for tank operation and protection from spill or a fire
resulting from the spill. The reader is referred to para.'s 2-3 through 2-3.6 and Fig.'s 2-8, 2-9 and 2-10.
3-6.1 Tank pads are preferably constructed of a loamy or clay soil containing some sand so that a smooth area can be
graded and its shape hold up. Fig.'s 2-8, 2-9 and 2-10 show what is needed in tank pad shape and slope. The longest
slope should be approximately 10 (degree) from horizontal. Other shorter slopes will be greater. The low point should be
where the tank drain will end up when the tank is unrolled. A small ditch and a basin for the drain line and the drain valve
can be excavated by hand at the time the tank is unrolled. The low point described is to permit maximum pump out of
the tank and drainage through the drain line.
The base of the tank pad area must be virgin soil, cut soil, or highly compacted. To avoid damage to the tank bottom,
sticks, stones, or sharp objects must be removed prior to installing the tank.
3-6.2 Tank berms are constructed as shown on Fig.'s 2-8 and 2-9. They may be constructed before, after, or
simultaneously with tank pad construction, depending on job conditions. In any case, it is necessary that the tank pad be
cleared of any rocks, clumps, etc., that roll on during berm construction. It is recommended that tank pad rough grading
be completed before berm construction and that it be finished up after berm construction. The preferred materials are
soils containing a fairly high clay content to hold shape and provide sealing.
The berm should be compacted as it is constructed. Alternate materials are sand bags or the sand grids as described in
para. 2-3.2b.
3-3
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