Document ID: chunk:federal_register_of_legislation:F2013C00288:reg:20:p9
Version: federal_register_of_legislation:F2013C00288
Segment Type: reg
Provision Reference: reg 20 (pt 9/10)
Character Range: 1675156–1677874

iron content.
The resulting ACL(EC50), ABC and SQG(EC50) values are:
ACL(EC50) CEC based:   510 mg/kg
ACL(EC50) pH based:   1300 mg/kg
ACL(EC50):    510 mg/kg (the lower of the two ACLs that apply to this soil)
ABC:     25 mg/kg
SQG(EC50):    535 mg/kg, which would be rounded off to 530 mg/kg.

7.8              Reliability of the soil quality guidelines
Based on the criteria established in the methodology for SQG derivation (Schedule B5b), all the Cu  SQGs were considered to be of high reliability. This resulted as the toxicity data set easily met the minimum data requirements to use the SSD method and there were normalisation relationships available to account for soil characteristics.

7.9              Comparison with other guidelines
A compilation of SQGs for Cu from a number of jurisdictions is presented in Table 61. These SQGs have a variety of purposes and levels of protection and therefore comparison of the SQGs amongst each other and with the Cu SQGs is problematic. As well, the vast majority of the international SQGs are not soil-specific nor do they account for ageing and leaching. One would therefore expect that the ACLs could be higher than other internationals SQGs. The international guidelines for Cu range from 14 to 1,000 mg/kg (added or total Cu) both being from member countries of the European Union (Carlon 2007). The superseded interim urban EIL (NEPC 1999) for Cu was 100 mg/kg total Cu and therefore in the middle of the range of the international Cu guidelines.

Overall, the superseded interim urban EIL lies in the lower to middle part of the range of ACLs for fresh Cu contamination, while the superseded interim urban EIL lies at the lower third of the range of ACLs for aged contamination.

All of the soil-specific ACL values for urban residential land/public open space land use (irrespective of the toxicity data on which they were based) fell within the range of the international residential SQGs, the one exception being the ACLs based on EC50 for soils where the Cu has low bioavailability (that is, high pH and high CEC), which were greater than 1,000 mg/kg added Cu.

However, this was a CEC-based ACL and, as stated earlier, when the soil pH is greater than 6, the pH-based ACLs will limit the amount of Cu that can be present in soil. When this was taken into account, all the soil-specific ACL values for residential land use fell within the range of international SQGs.

Similarly, all the ACLs for commercial/industrial land use, with the exception of the aged ACLs based on EC50, fell within the range of international SQGs for Cu. The one exception was the ACL(EC50) value that would permit concentrations nearly twice (that is, 1,800 mg/kg added) that