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(a) General. Sample piles that are either specifically configured for sampling (see paragraph (b) of this section) or that are of conical shape (see paragraph (c) of this section). If sampling from either of these shapes is not possible, conduct contemporaneous sampling, in accordance with the procedures in §761.348, or obtain the approval of the Regional Administrator for an alternate sampling plan in accordance with §761.62(c).
(b) Specifically configured piles. A specifically configured pile is a single flattened pile in the shape of a square or rectangle having no restrictions on length or width but restricted to 30 cm (1 foot) in depth. A square shaped pile facilitates sampling site selection for the first level sample. Select eight 19-liter samples from the pile and composite them into one 19-liter sample as follows:
(1) Divide the pile into quarters.
(2) Divide each of the quarter sections into quarters (i.e., into sixteenths of the original pile).
(3) Select two sixteenths from each of the four quarters, according to one of the two following options:
(i) Randomly select the two sixteenths from one quarter and sample the sixteenths occupying the same positions in each of the other three quarters.
(ii) Randomly select two sixteenths from each of the four quarters (i.e., perform a random selection four different times).
(4) At this point the eight selected sixteenths undergo further division and sample selection. Divide each of the eight selected sixteenths into four equal parts. Using a random number generator or random number table, select one of the four equal parts from each of the eight equal areas. If each of the four equal parts has a volume >76 liters when projected downwards 30 cm, continue to divide each selected area into four equal parts, and select one of the parts, until each selected area has a volume of <76 liters but ≥19 liters. When projected to a depth of 30 cm, a square having a 25 cm side or a circle having a diameter of approximately 28.5 cm equals a volume of approximately 19 liters. The volume of 76 liters is equal to the volume enclosed by a square having a side of 50 cm (or other shape having an area of 250 cm2) projected to a depth of 30 cm.
(5) Take one sample of approximately 19 unsorted liters of waste from each of the eight selected areas. Place each sample into a separate 19-liter container, allowing only sufficient space at the top of the container to secure the lid.
(6) Composite the eight 19-liter samples in accordance with §761.350.
(c) Conical-shaped piles. If it is necessary to sample a pile which is too large to be spread on the site to a uniform thickness of 1 foot or 30 cm, or if there are too many piles to spread out in the space available, use the following procedure to sample the piles. This procedure assumes that the shape of the piles is analogous to a cone; that is, having a circular base with PCB bulk product waste or PCB remediation waste destined for off-site disposal stacked up uniformly to a peak that is a point centered above the center of the circular base. Collect eight 19-liter samples as follows:
(c)(1) Collecting samples from more than one pile. If the PCB bulk product waste or PCB remediation waste consists of more than one pile or container, assign each pile or container an integer number and then generate seven random integer numbers to select the piles from which you will collect samples. It is possible that this random selection procedure will result in selecting the same pile number more than once, even if seven or more piles are present. If so, sample the pile once and restart the sampling collection process to collect additional samples. Do not collect multiple samples from the same location in the pile.
(c)(2) Collecting samples from a single pile. If only one pile or container is present, collect all eight samples from the same pile.
(c)(3) Setting up the sample site selection system from a pile. Locate a sample in a pile by the use of three parameters: a particular radial direction, "r," from the peak at the center of the pile to the outer edge at the base of the pile; a point, "s," along that radial direction between the peak of the pile and the outer edge of the base of the pile; and a depth, "t", beneath point "s." The top of the sample material will be below depth t, at point s, on radius r. Use a rod, dowel, stake, or broom handle as a marker. Nail or otherwise fasten to the top of the marker two pieces of string or cord of sufficient length and strength to reach from the top of the marker at the top of the pile to the farthest peripheral edge at the bottom of the pile, when the marker is positioned at the top or apex of the pile. Pound or push the marker into the top center (apex) of the pile, downward toward the center of the base. Insert the marker for at least 30 cm or one foot until the marker is rigidly standing on its own, even when the cord is pulled tight to the bottom peripheral edge of the pile. Ensure that the marker protrudes from the top of the pile sufficiently to allow the strings to move easily around the pile when they are pulled tight. Select the three parameters and the sampling location as follows:
(i) Determine the radial component (r) of the location for each sample.
(A) Tie to a stake or otherwise fasten one of the strings at "b," the bottom of the pile, as a reference point for finding r.
(B) Measure the circumference "c," the distance around the bottom of the pile. Determine r from b in one of two ways:
(1) Multiply c by a randomly generated fraction or percentage of one.
(2) Select a random number between one and the total number of centimeters in c.
(C) Locate r by starting at b, the place where the fixed string meets the base of the pile, and travel clockwise around the edge of the pile at the base for the distance you selected in paragraph (c)(3)(i)(B) of this section.
(D) Fasten the second string at the selected distance. The second string marks the first parameter r.
(ii) Determine the second parameter s of the location for each sample.
(A) Measure the distance, l, along the string, positioned in paragraph (c)(3)(i)(D) of this section, from the top to the bottom of the pile at the selected radial distance r. Determine the distance s from l in one of two ways:
(I) Multiply l by a randomly generated fraction or percentage of one.
(2) Select a random number between one and the total number of centimeters in l.
(B) Mark, for example by placing a piece of tape on the string positioned according to paragraph (c)(3)(i)(D) of this section, the distance s, up from the bottom of the pile on the string at r.
(iii) Determine the third and final parameter t of the location for each sample.
(A) Mark and number 1 cm intervals from one end of a rigid device, for example a rod, dowel, stake, or broom handle, for measuring the distance from the top of the pile to the bottom at the point s selected in paragraph (c)(3)(ii)(B) of this section. The marked and numbered device shall be of sufficient strength to be forced down through the maximum depth of the pile and sufficient length to measure the depth of the waste in the pile at any point.
(B) Take the measuring device, constructed according to paragraph (c)(3)(iii)(A) of this section, and at position s, push the end of the device marked with zero straight down into the pile until it reaches the bottom of the pile or ground level. The vertical distance "v" is the number of centimeters from the surface of the pile at point s on the string to the bottom of the pile or ground level. Read the distance v on the measuring device at the surface of the pile. From the distance v, determine t, in one of two ways:
(1) Randomly generate a fraction of one and multiply the fraction times v.
(2) Select a random number between zero and the total number of centimeters of the vertical distance v.
(iv) Dig a hole straight down into the pile for t centimeters (inches) from the surface of the pile at s.
(v) At depth t, directly under the s mark on the string, outline the top of the sample container and collect (shovel) all waste under the outline in the following order of preference in paragraphs (c)(3)(v)(A) through (c)(3)(v)(C) of this section. It is possible that some of the eight sampling locations will not provide 19 liters of sample.
(A) For a depth of 30 cm.
(B) Until the container is full.
(C) Until the ground level is reached.
(d) Compositing the samples. Composite the eight 19-liter samples and subsample in accordance with §761.350. Send the subsample to a laboratory for further sampling as described in §761.353 and 761.355 and for chemical extraction and analysis. If there is insufficient sample for a 19-liter sample from the composite sample composed of the eight iterations of sample site selection, according to the procedures in paragraphs (c)(3)(i) through (c)(3)(v) of this section, select additional sample sites, collect additional samples and composite the additional waste in the samples until a minimum of 19 liters is in the composite.
[63 FR 35462 June 29, 1998; 64 FR 33762 June 24, 1999]