Environmental Protection Act 1990 - Part IIA Contaminated Land: statutory guidance edition 2

PART 2: Definitions of Terms and General Material

A.7 Unless otherwise stated, any word, term or phrase given a specific meaning in Part IIA of the Environmental Protection Act 1990 has the same meaning for the purposes of the guidance in this Chapter.

A.8 Any reference to "Part IIA" means "Part IIA of the Environmental Protection Act 1990". Any reference to a "section" in primary legislation means a section of the Environmental Protection Act 1990, unless it is specifically stated otherwise.

Risk Assessment

A.9 The definition of contaminated land is based upon the principles of risk assessment. For the purposes of this guidance, "risk" is defined as the combination of:

(a) the probability, or frequency, of occurrence of a defined hazard (for example, exposure to a property of a substance with the potential to cause harm); and

(b) the magnitude (including the seriousness) of the consequences.

A.10 The guidance below follows established approaches to risk assessment, including the concept of contaminant-pathway-receptor. (In the technical literature, this is sometimes referred to as source-pathway-target.)

A.11 There are two steps in applying the definition of contaminated land.

STEP ONE

A.12 The first step is for the local authority to satisfy itself that a "contaminant", a "pathway" (or pathways), and a "receptor" have been identified with respect to that land. These three concepts are defined for the purposes of this Chapter in paragraphs A.13 to A.15 below.

A.13 A contaminant is a substance which is in, on or under the land and which has the potential to cause harm or to cause pollution of the water environment.

A.14 A receptor is either:

(a) a living organism, a group of living organisms, an ecological system or a piece of property which

(i) is in a category listed in Table A (see below) as a type of receptor, and

(ii) is being, or could be, harmed, by a contaminant; or

(b) a water environment which is being, or could be, polluted by a contaminant.

A.15 A pathway is one or more routes or means by, or through, which a receptor:

(a) is being exposed to, or affected by, a contaminant, or

(b) could be so exposed or affected.

A.16 It is possible for a pathway to be identified for this purpose on the basis of a reasonable assessment of the general scientific knowledge about the nature of a particular contaminant and of the circumstances of the land in question. Direct observation of the pathway is not necessary.

A.17 The identification of each of these three elements is linked to the identification of the others. A pathway can only be identified if it is capable of exposing an identified receptor to an identified contaminant. That particular contaminant should likewise be capable of harming or, in the case of the water environment, be capable of polluting that particular receptor.

A.18 In this Chapter, a "pollutant linkage" means the relationship between a contaminant, a pathway and a receptor, and a "pollutant" means the contaminant in a pollutant linkage. Unless all three elements of a pollutant linkage are identified in respect of a piece of land, that land should not be identified as contaminated land. There may be more than one pollutant linkage on any given piece of land.

A.19 For the purposes of determining whether a pollutant linkage exists (and for describing any such linkage), the local authority may treat two or more substances as being a single substance, in any case where:

(a) the substances are compounds of the same element, or have similar molecular structures; and

(b) it is the presence of that element, or the particular type of molecular structures, that determines the effect that the substances may have on the receptor which forms part of the pollutant linkage.

STEP TWO

A.20 The second step in applying the definition of contaminated land is for the local authority to satisfy itself that both:

(a) such a pollutant linkage exists in respect of a piece of land; and

(b) that the pollutant linkage:

(i) is resulting in significant harm being caused to the receptor in the pollutant linkage,

(ii) presents a significant possibility of significant harm being caused to that receptor,

(iii) is resulting in the significant pollution of the the water environment which constitutes the receptor, or

(iv) is likely to result in a significant possibility of such pollution being caused.

A.21 In this Chapter, a "significant pollutant linkage" means a pollutant linkage which forms the basis for a determination that a piece of land is contaminated land. A "significant pollutant" is a pollutant in a "significant pollutant linkage".

A.22 The guidance in Part 3 below relates to questions about significant harm and the significant possibility of such harm being caused. The guidance in Part 4 below relates to the significant pollution of the water environment and the significant possibility of such pollution being caused.