Conducting Subsurface Environmental Investigations in Urban Watersheds - Urban Watersheds: Geology, Contamination, and Sustainable Development - page 144

• Drilling or advance difficulties
• Equipment failures
• Drilling difficulties
• Weather conditions

After extraction, each soil sample is inspected and information related to the site's geology
and soil properties is recorded in the field log book, and shown in the following:

• Soil or sediment type (i.e., sand, clay, etc.) using the Unified Soil Classification
System
• Grain size
• Grain shape
• Grain sorting
• Grain composition
• Consistency
• Plasticity
• Stratigraphy
• Observable depositional features and bedding
• Presence of fill or anthropogenic materials or substances
• Color using the Munsell Color Chart developed by Munsell (1905)
• Color changes
• Degree of saturation
• Field screening results
• Odors
• Location of sample collection for laboratory analysis, if any

Table 4.2 lists the grain size dimensions used to differentiate between clay, silt, and sand.
Figure 4.16 is a diagram that shows the relative size difference between a particle of sand,
silt, and clay. Figure 4.17 is a soil textural chart used in the field as a guide to identify and

TABLE 4.2
Soil Classification by Grain Size

Diameter (Range in mm or
Sieve Size) Soil Type

Very Coarse Sand 1.0-2.0

Coarse Sand 0.5-1.0

Medium Sand 0.25-0.50

Fine Sand 0.125-0.25

Very Fine Sand 0.0625-0.125

Silt 0.0039-0.0625

Clay <0.0039

Source: Modified from New Jersey Department of

Environmental Protection, Field Sampling
Procedures Manual , Trenton, NJ, 2005.