Retrospective Evaluation of Cured-in-Place Pipe - (NEPIS)(EPA ...

5.2.4 Locations of Soil Samples. The trench was divided into six regions (Figure 5-3). Soil
samples collected from each region were placed in airtight bags to avoid foreign contamination and/or
loss of moisture. The samples were numbered as shown in Table 5-1.
Figure 5-3. Location of Soil Samples
(Columbus 8-in. Site)
Table 5-1. Designation of Collected Soil Samples
(Columbus 8-in. Site)
66
Soil Sample Location Sample ID
Subgrade 2 + 63 1
3 ft below subgrade 2
5 ft below subgrade 3
6 ft below subgrade - just above
crown
Bedding along the spring line 5
On the invert 6
5.2.5 Analysis of Soil Samples. Standard test methods ASTM C136 and ASTM C128 were
followed to classify the soil and determine its particle size distribution. In addition to these tests, the pH
of the soil samples was measured using a pH meter.
5.2.5.1 Particle Size Distribution. The soil gradation analysis followed ASTM C136. Based on
visual inspection, the soil samples were categorized as fine aggregates. Some large particles (e.g.,
asphalt, rocks) (see Figure 5-4) were also present, but were considered a foreign material and were
excluded from the sieve analysis. For the analysis, 500 g of soil material was taken from each of the six
soil samples and placed on a No. 4 sieve (4.76 mm). For all samples (excluding the large foreign
material), 85 to 95% of the particles passed through the No. 4 sieve.
Figure 5-4. Collected In-Situ Soil Samples (Columbus 8-in. Site)
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