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XYZ Example - Project Initiation

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What are RA tiers?

Initiation 

Problem Identification

Receptor Characterisation

Exposure Assessment

Toxicity Assessment

Risk Characterisation

RM Decisions

Project Initiation

ERA Tier 1

ERA Tier 2 (Advanced)

ERA Tier 3 (Advanced)

Glossary

FAQ's

 

 

Project Initiation

This stage in the ERA framework consists of a series of preliminary tasks that are necessary before a decision is made to conduct an ERA. These steps are not necessary if a contaminated site has already been identified. Initiation consists of four main tasks: identification of potential sites, preliminary site characterisation, site classification, and prioritisation.  These are explained in detail in the section on Initiation.

Site Identification

XYZ Enterprises is an industrial firm involved in a variety of activities including the manufacture of large steel products and the storage/recycling of scrap metal. They own a number of industrial sites including one located at 7B Anywhere Drive in the Allsorts Industrial Park, at which scrap metal is stored prior to sale, and steel products are finished (electroplated) for sale. XYZ Enterprises are undertaking assessment of all their sites as a part of a risk management programme to identify potential liability issues.

This site was identified from the Regional Council’s ‘Hazardous Substance Land Use and Contaminated Sites Register’ based on its current site uses and because it is thought to have been a timber treatment plant.

The information contained in the register for this site came from a former county council engineer who remembered advising the then owners on the construction of a treatment facility and drying racks, and from more recent building inspections.

The site is registered as a Possible Hazardous Substance Land Use site, but neither the owner nor the regional council has carried out investigations to confirm this.

Of the sites owned by XYZ, a further seven sites were identified as being currently or historically associated with landuses that may have involved hazardous substances.

Preliminary Site Characterisation

The purpose of a preliminary site characterisation is to identify whether there are contaminants of concern at the site, and whether there are receptors that are likely to be affected by these contaminants. This involves gathering some preliminary information about the site, from existing information sources, interviews with people familiar with the site, and inspections of the site and surrounding area.

At the conclusion of this step you should have a broad idea of what contaminants there may be on the site and what receptors may be exposed to these contaminants.

While this web site focuses on ecological risk assessment, in practice it is difficult to separate human health impacts from impacts to plants and animals. It is good practice to consider both human and ecological effects at an early stage.

Some of the preliminary information that should be collected at this stage is outlined below.

XYZ Enterprises, 7B Anywhere Drive, Allsorts Industrial Park

Grid reference:

U14 279905 639604

General description:

2.578 ha, southwestern corner borders the ABC River, northern eastern border adjacent to Anywhere Drive. Possible former timber treatment site. Currently scrap metal and steel product finishing.

Site Ownership

Certificate of Title

Previous Owners: 1901 James & Lilleth Buyer, cattle farmer; 1935 Henry & Dorothy Seller, dairy farmer; 1962 Timothy Tree & Tony Trunk, sawmillers, mortgaged by Only Bank; 1972 remortgaged by same owners to Tiny Bank; 1984 Tree Trunk Construction Ltd mortgaged to Bigger Bank; 1993 XYZ Enterprises mortgaged to Huge Bank.

Surrounding landuses:

Northern boundary: light engineering firm present on site for approx. 25 years. Northwestern boundary: agricultural land, dairy farm. Northeastern boundary: road, other industrial (car repairs, spray painters, etc.). Southern boundary: vacant, industrial land, formerly wood storage?/agriculture.

Landuse History

Farming 1901 – 1962

Sawmill 1962 – 1993

Scrap metal yard. 1993 – present

Unconfirmed report (neighbour Mrs B. Body) of a spill in the late 70s.

Hydrogeology:

(Source: Regional Council records)

Soil — sandy silt throughout most of the area around the site, no information available specifically for the site. Groundwater — 2–3 m depth through this area with an overlying semi-confining layer 1–2 m thick, no information available specifically for the site. Wells register — a groundwater well was drilled for water supply purposes on a property to the southeast of the site approximately 55 m from the southeastern boundary. The borehole log indicates the hole was drilled to 20 m, water table at 2.58 m, sandy silt encountered down to 2.0 m, with sand lenses interbedded with silt and sandy silt for the remainder of the bore.

Potential Contaminants:

(Source: Regional Council Hazardous Substance Land Use and Contaminated Site Register)

Copper, chromium, arsenic suspected.

Possibly zinc, lead, iron.

Possible petroleum hydrocarbons: BTEX

Other Site Uses:

(Source: Regional Council Consent Files)

Water rights obtained and renewed by Tree & Trunk Ltd to take water from the ABC River from 1975 to 1980. Amounts ranged from 20 m3 water per day in 1975 to 100 m3 water per day in 1980. Transferred and renewed by XYZ Ent. in 1993. No other consents information available.

City Council Trade Waste Permit:

Nil, no history for this site. Septic tank on site for domestic sewage.

City/Borough Council Property Files:

Located at central City Council offices, building unit. Files show that in 1972 building permits were obtained for the construction of two buildings and a lean-to with drying racks. File notes of several site visits through to 1974 indicate that there was an old "treatment pit" at the site. In 1979, a building permit was obtained to extend the lean-to in length and width. XYZ was granted building consents in 1993 to demolish existing buildings, construct a new steel framed warehouse, install a relocatable building as an office.

Other Data:

All local oil companies have been contacted regarding petrol or diesel tanks on the site. HasBeen Oil has records relating to supplying petrol to the site, but there are no records of the installation or servicing of a tank or a starting date for the supply.

Aerial Photos:

Two, flown in 1975 & 1989. The former shows the location of Tree & Trunk Ltd buildings and lean-to of which one building and the lean-to had been removed in the latter photo.

Ecological Resources:

No local or Conservation Dept reserves within the immediate vicinity of the site; riparian wetland reserve 450 m downstream on the true right bank of the ABC River; ABC River itself; 1.5km to coast; no information available specifically for the site.

 

Site location and site layout plans

Site location and site layout plans should be prepared at an early stage. They need not be complete but should provide sufficient information on the locality of the site, the position of key site features (areas of suspected contamination, chemical storage areas, dumps, drains etc) and important off-site features (e.g ABC River).

Site Characterisation Check List

It is often worthwhile to summarise as much information as possible in a table or checklist. A site characterisation checklist such as that presented is often useful as it asks a consistent series of questions about a site.  The checklist contains information such as:

  • General site details
  • Site access
  • Landuse
  • Possible contaminants
  • Physical Description of site
  • Surface water hydrology
  • Nearby habitat
  • Groundwater hydrology

A blank checklist is also provided to help you to undertake a site characterisation for your own site.

Site Classification

XYZ Enterprises owns a number of industrial sites around the district, of which eight have been or are associated with Hazardous Substances Land Uses. However for a variety of reasons it may wish to prioritise its sites, so it can address those that pose a greatest potential threat to the environment first.

To achieve this some form of classification and prioritisation needs to occur.

Several sites could be classified in relation to their potential for contamination, and/or the presence of receptors of concern. An example of this is presented below.

Many classification schemes refer to potential receptors assuming that there is a complete pathway from the contaminant of concern to that receptor. This may not always be the case and the assessor should be careful about including or excluding receptors at such a preliminary stage.

Site

Location

Potential Contaminant of Concern

Classification of Contamination

Reason

Potential

Receptors

Classification of Ecological Receptors

DEF Holdings Ltd

Allsbrook

Diesel

Probably Yes

Tank in place

ABC River tributary adjacent to site, groundwater

Probably Yes

GHI Co. Ltd

Allsbrook

? Solvents

Unknown

Records can’t confirm activities

Site adjacent to agricultural land

Probably Not

JKL Trading

Newtown

Petrol/diesel

Probably Yes

Records of tanks pulled

None apparent, urban site

Probably Not

MNO Ltd

Huston

CCA/B

Possible

Treatment not confirmed

None apparent, urban site

Probably Not

PQR Enterprises

Newtown

CCA/B

Probably Not

Treatment at another site

None apparent, urban site

Probably Not

STU Ltd

Allsorts

Diesel/PCP

Probably yes

Records of diesel supply & treatment

ABC River 500m from site,

DOC wetland 1.5km

Possible

VW Enterprises

Huston

? Solvents /

petroleum products

Unknown

Records can’t confirm activities

ABC River tributary 300m from site

Possible

XYZ Enterprises

Allsorts

CCA/Petrol/

Metals

Probably Yes

Records of petrol supply and treatment activity

ABC River adjacent to site,

DOC wetland 450m, coast 1.5km

Probably Yes

 

A summary site classification for the above should look like:

Site

Potential Contaminants

Potential Receptors

DEF

4

4

GHI

?

8

JKL

4

8

MNO

?

8

PQR

8

8

STU

4

?

VW

?

?

XYZ

4

4

? = possible or unknown
4 = probable
8 = unlikely

The tables above help to classify site contamination in very qualitative probabilistic terms. This may provide little help in determining what site or sites pose the highest risk to the environment, and some other methods to prioritise sites may be necessary.

Prioritisation

A priority ranking for the XYZ Enterprises sites could be qualitatively undertaken based on the classification matrix described previously.

 

Site

Potential Contaminants

Potential Ecological Receptors

Priority

DEF

4

4

3

GHI

?

8

-

JKL

4

8

-

MNO

?

8

-

PQR

8

8

-

STU

4

?

2

VW

?

?

4

XYZ

4

4

1

 

For example, sites located in Allsorts Industrial Park will be addressed first due to the proximity of the suburb and industrial park to the ABC River and a DOC riparian wetland reserve.

Sites where activities and/or potential contaminants are unknown need to be carefully considered when ranking them against sites where more information is available.

Rapid Hazard Assessment

A more detailed prioritisation tool is the Rapid Hazard Assessment. This is a method that involves scoring each site based on a number of criteria to determine the relative risk to people and, to a lesser extent, the environment from on-site contaminants. The resulting scores are collated into an index, which determines the site’s priority relative to other sites. The RHA is being updated to reflect best management by regional councils. The revised RHA should be available in late 2001.

 

Summary

Based on the information obtained during the preliminary site characterisation, XYZ Enterprises has classified the site at 7B Anywhere Drive as probably contaminated with probable ecological receptors that may be affected by the contamination. When compared to other sites, this site was prioritised as a top priority for an ERA and the assessor proceeded to a Level 1 Assessment.

Where next?

The next step is a Tier 1 assessment.

 

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