Document ID: chunk:federal_register_of_legislation:F2013C00288:reg:2:p17
Version: federal_register_of_legislation:F2013C00288
Segment Type: reg
Provision Reference: reg 2 (pt 17/21)
Character Range: 85693–88548

various soil components and decreasing their biological availability. Hence, toxicity can be affected by the physicochemical or chemical properties of the soil including clay content, cation exchange capacity (CEC) measured in centi-mole charge/kg (cmolc/kg), pH, iron and organic carbon content.

For the purposes of EIL derivation, a contaminant incorporated in soil for at least two years is considered to be aged for the purpose of EIL derivation. The majority of contaminated sites are likely to be affected by aged contamination. Fresh contamination is usually associated with current industrial activity and chemical spills.

In some cases insufficient data on aged contamination was available to apply the EIL methodology, and where possible, ageing factors based on relevant studies have been applied to determine a soil value for aged contamination.

EIL determination for fresh contamination (that is, present for less than two years) for the relevant contaminants should be site-specifically determined by reference to the relevant tables in Schedule B5c.

    2.5.10      Determining site-specific EILs
Detailed information on the derivation of the EILs is provided in Schedule B5c. The following section describes the steps that are taken to derive site-specific EILs. A spreadsheet is included in the ASC NEPM Toolbox which can also be used for calculating site-specific EILs.

A. EILs for Ni, Cr III, Cu, Zn and Pb aged contamination (>2 years)

Steps 1–4 below describe the process for deriving site-specific EILs for the above elements using Tables 1B(1) – 1B(4), which can be found at the end of this Schedule.

        1. Measure or analyse the soil properties relevant to the potential contaminant of concern (see Table 4). Sufficient samples need to be taken for these determinations to obtain representative values for each soil type in which the contaminant occurs.

        2. Establish the sample ACL for the appropriate land use and with consideration of the soil-specific pH, clay content or CEC. The ACL for Cu may be determined by pH or CEC and the lower of the determined values should be selected for EIL calculation. Note that the ACL for Pb is taken directly from Table 1(B)4.

        3. Calculate the contaminant ABC in soil for the particular contaminant and location from a suitable reference site measurement or other appropriate method.

        4. Calculate the EIL by summing the ACL and ABC:

   EIL = ABC + ACL

B.  EILs for As, DDT and naphthalene

EILs for aged contamination for DDT and naphthalene are not available and the adopted EIL is based on fresh contamination taken directly from Table 1B(5). The EILs for As, DDT and naphthalene are generic i.e. they are not dependent on soil type and are taken directly from Table 1B(5). Only EILs for fresh contamination are available for As, DDT and naphthalene