Document ID: chunk:federal_register_of_legislation:F2013C00288:reg:1:p1
Version: federal_register_of_legislation:F2013C00288
Segment Type: reg
Provision Reference: reg 1 (pt 1/6)
Character Range: 2898667–2901663

1                   Introduction

1.1              Background
This document presents the health investigation levels (HILs) for soil and describes their derivation. Schedules B7a and B7b to the National Environment Protection (Assessment of Site Contamination) Measure 1999 (the NEPM) have been updated and combined in this revised Schedule B7.

A review of the NEPM (NEPC 1999) was carried out during 20052006 at the request of the National Environment Protection Council (NEPC). The review recommended changes to improve the effectiveness and efficiency of the NEPM by addressing technical, scientific and health risk issues raised by site assessors, consultants, land developers, auditors and the public (NEPC 2006).

The recommendations from the NEPM review that relate to the HILs are as follows:
    * Recommendation 5 — revise existing HILs in light of current knowledge
    * Recommendation 6 — derive additional HILs for priority substances
    * Recommendation 7 — develop guidance to further clarify the use of HILs to counter their inappropriate use as remediation (i.e. clean-up) criteria
    * Recommendation 8 — develop HILs for a priority list of carcinogenic contaminants
    * Recommendation 15 — develop HILs, in a prioritised fashion, for all non-dioxin persistent organic pollutants (POPs) not addressed in the original NEPM (NEPC 1999).
The requirement for additional HILs was also discussed at the 5th National Workshop on the Assessment of Site Contamination (NEPC 2003), at which some new HILs were proposed, and a list of possible candidate substances was produced.

This revised Schedule B7 addresses the findings of the NEPM review process. It presents an expanded list of HILs in accordance with the above recommendations, and sets out the revised and updated methodology adopted to derive the HILs. The methodology presented here is also applicable to site-specific health risk assessment. Further guidance on site-specific health risk assessment is provided in Schedule B4 Guideline on site-specific health risk assessment methodology.

1.2              Purpose of HILs
The HILs (including interim HILs) are scientific, risk-based guidance levels (or Tier 1 criteria) designed to be used in the first stage of an assessment of potential risks to human health from chronic exposure to contaminants. The HILs are referred to by regulators, auditors and consultants in the initial process of assessing site soil contamination.

HILs are defined as the concentration of a contaminant above which further appropriate investigation and evaluation will be required.

Levels in excess of the HILs do not imply unacceptability or that a significant health risk is likely to be present. Similarly, levels below the HILs do not necessarily imply acceptability or that a health risk is not likely to be present, particularly if more sensitive populations[1] are present or the assumptions for land use scenarios are not appropriate.

The HILs are designed to be used to define