Chemical Testing

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7_BEACON Tech Report (FINAL)

discussed in Section 2.0 of this report. These criteria include chemical testing, sediment grain

size, color, particle shape, debris, and compactability/moldability. Each source of potential

beach sediment will be analyzed against each of these criteria to determine if the sediment is

beach compatible and which site should receive it. This section describes each of these criteria.

4.2.1

Chemical Testing

BEACON and resource agencies have specified that material with a chemical content

incompatible with beach fill is not desired. BEACON proposes to conduct chemical testing for

each potential sand source if an initial investigation warrants testing. However, depending on the

sand source, the types and amount of chemical testing may change. Some sand sources may have

more potential of containing contaminants than others, in which case more testing would occur.

Regarding chemical compatibility, sediment samples shall be stored per USEPA guidelines.

Samples shall be taken from five (5) different sites, at both the source and disposal sites. The

volume of sediment samples shall be sufficient to test grain size compatibility and chemistry

suitability per the Inland Testing Manual (ITM) (USEPA and USACE 1998). Chemical

suitability shall comply with the criteria outlined in the ITM. Chemical testing may encompass

metals, organic compounds (PCB's, pesticides, and polycyclic aromatic hydrocarbons), total

organic carbon (TOC), and possibly certain bacteria. At a minimum, the basic suite of bulk

chemistry testing will be done as a screening mechanism for more detailed tests. Bulk chemistry

testing is specified in the ITM.

Regulatory agencies are often more concerned with fine-grained sediments than coarser

sediments for a number of reasons. First, many contaminants have a greater affinity for clay and

silt than for sand (USEPA and USACE 1998, p.8-6). Second, fines can settle out in calmer

waters offshore, burying reef habitat. Third, fines can remain in suspension for a certain period

creating turbidity that obscures feeding grounds for sensitive birds.

Chemical testing may not be necessary or as complex if a site evaluation indicates the material is

not a "carrier of contaminants." The ITM (p. 4-1) notes the following list of conditions that will

tend to preclude contamination:

Material is primarily sand, gravel, and/or inert material;

Sediments are from locations far removed from sources of contaminants (based on agency

judgement);

Sediments were deposited in pre-industrial times; and

Sediments were not exposed to modern sources of pollution.

Additionally, examples of potential contemporary sources of pollution are also presented in the

ITM (p. 4-3) as follows:

Urban and agricultural runoff;

Sewer overflows/bypassing;

Industrial and municipal wastewater discharges;

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Moffatt & Nichol Engineers