EIS 537
Tomago a'uminium smelter: proposed waste landfill at
Wallaroo : environmental impact assessment fQ3 -3 ABO1 8624
DEPARTMENT OF ENVIRONMENT & PLANNING G-)
Tomago Aluminium Smelter Proposed Waste Landfill at Wallaroo
ENVIRONMENTAL IMPACT ASSESSMENT Tomago Aluminium Smelter Proposed Waste Landfill at Wallaroo
ENVIRONMENTAL IMPACT ASSESSMENT
DEPARTMENT OF ENVIRONMENT AND PLANNING SYDNEY 1984 © Crown copyright 1985 ISBN 0 7240 8509 2 85/5 CONTENTS
Page
INTRODUCTION 1 2 THE PROPOSAL
2.1 The Waste Stream 3 2.2 Transport to Disposal Site 4 2.3 The Site 4 2.4 Site Selection 4 2.5 Method of Disposal 5 3 THE EXISTING ENVIRONMENT
3.1 General 6 3.2 Surface Drainage 6 3.3 Flora, Fauna, Archaeology 6 3.4 Noise 7 3.5 Meteorology 7 3.6 Subsurface Character of Disposal Site 7 4 PROPOSED DESIGN AND OPERATIONAL SAFEGUARDS
4.1 Water Quality and Conditions 9 4.2 Noise 10 4.3 Air Pollution (Dust) 10 4.4 General 10 4.5 Monitoring 11
5 REVIEW OF SUBMISSIONS
5.1 Private Submissions 12 5.2 State Government Agency Submissions 14 5.3 Port Stephens Shire Council Submission 18
6 MAIN ISSUES 19
7 ASSESSMENT OF ENVIRONMENTAL IMPACT
7.1 Alternative Disposal Methods and Sites 20 7.2 Effects on Local Economy and Amenity 21 7.3 Effects on Native Fauna, Flora and 22 Archaeological Relics 7.4 Operational Safeguards 22 7.5 Performance of the Disposal Site 24 7.6 Summary 28
8 CONCLUSIONS AND RECOMMENDATIONS
8.1 Conclusions 31 8.2 Recommendations 33 EIS 37 REFERENCES 36
APPENDICES
1 List of Persons and Community 38 Organisations Who Made Individual Submissions on E.I.S.
2 Submission by Port Stephens Shire 40 Council
3 Comment by State Pollution Control Commission 42
FIGURES
1 Locality Plan
2 Disposal Site and Environs FOREW ORD A development application for the establishment of a site at Wallaroo for landfill disposal of solid waste from the Tomago Aluminium Smelter, has been lodged by Tomago Aluminium Company Pty. Ltd. with the Port Stephens Shire Council. The proposed development is designated development within the meaning of Schedule 3 of the Environmental Planning and Assessment Regulation, 1980. The development application is supported by an environmental impact statement. Under the relevant planning instrument, the proposed development is permissible with the consent of the Shire Council.
Following the public exhibition of the environmental impact statement and development application, the Minister for Planning and Environment, pursuant to Section 119(1)(b) of the Environmental Planning and Assessment Act, 1979, directed that an inquiry be held with respect to the environmental aspects of the proposed development. Where the Minister has directed that such an inquiry be held, Section 89 of the Act provides that the Minister shall determine the development application following consideration of the findings and recommendations of the Commission of Inquiry.
To assist in the determination of the application, the Department of Environment and Planning has undertaken an assessment of the development proposal. This report presents that assessment, and will serve as the Department's submission to the Commission of Inquiry. The report will be forwarded to the Company, to Port Stephens Shire Council, to Government agencies which provided advice to the Department and to the authors of submissions.
R. B. SMYTH Director of Environment and Planning INTRODUCTION
On 6 March 1981, development consent was granted to Tomago Aluminium Company Pty. Ltd. for the construction of an aluminium smelter at Tomago Road, Tomago, in the Shire of Port Stephens. Construction of the smelter proceeded immediately, following the granting of development approval. The construction was completed in March 1984 and the process of commissioning the smelter potlines commenced.
The production of aluminium by electrolytic reduction of alumina creates waste by-products, and the Company expects that, when fully operational, the Tomago Smelter will produce 9,000 tonnes of contaminated solid waste per year during its anticipated 50 year life. The first wastes will be produced in 1985.
By about 1988, the contaminated waste products will consist largely of spent cathode material (potlinings). During the reduction process the carbon cathode blocks and parts of their thermal insulation layers become impregnated with fluoride, sodium, iron and cyano-complexes. The principal contaminants contained in the waste, of environmental concern, are cyanides and fluorides.
The Company proposes to dispose of the smelter's contaminated solid waste by landfill methods on land which it has acquired for this purpose at Wallaroo, in the Shire of Port Stephens. The proposed waste disposal site is located on Portion 60, Parish of Thornton, and Portion 63, Parish of Sutton in the County of Gloucester.
The site, which is some 20 km north of the smelter (see Figure 1) is zoned Non-Urban 1(a) by Interim Development Order No.23 - Shire of Port Stephens, a deemed Environmental Planning Instrument. Under the provisions of that Instrument, the proposed development is permissible with the consent of the Shire Council. It is designated development within the meaning of Schedule 3 of the Environmental Planning and Assessment Regulation 1980.
In accordance with the provisions of the Environmental Planning and Assessment Regulation, the Company consulted the Director of the Department regarding the content of an environmental impact statement for the project, and the Director's requirements for the statement issued on 19 August 1983.
The development application and environmental impact statement were placed on public display for the period 23 August 1983 to 24 September 1983. In the light of a vigorous public response, the Port Stephens Shire Council extended the display period until 30 November 1983. Following the public exhibition, copies of all submissions which were received by the Council in relation to the proposal were forwarded to the Department of Environment and Planning. These submissions have been taken into account by the 2
Department in the preparation of this assessment report. Additionally, the Department sought and obtained advice on the proposal and various specific aspects of it from relevant public authorities, as well as additional information from the Company which has carried out further investigations of the proposed disposal area. On the basis of those investigations, the Company in 1984 revised and modified the detailed location and engineering design of the waste disposal facility.
In December 1983, the Minister for Planning and Environment directed that an inquiry be held into the environmental aspects of the proposed development pursuant to Section 119(1)(b) of the Environmental Planning and Assessment Act. Section 89 of the Act provides that the development application will be determined by the Minister following his consideration of the findings and recommendations of the Commission of Inquiry. 3
2 THE PROPOSAL 2.1 The Waste Stream
The environmental impact statement (E.I.S.) indicates (p.52) that when the Tomago Smelter operation achieves stable operation at full capacity (about 1988) it is expected to produce, on a long term average basis, a solid waste stream of some 14,160 tonnes/year (t/y). About 5,000 t/y of that will be disposed of by conventional means, leaving some 9,000 t/y of chemically contaminated material to be dealt with as proposed in the E.I.S., i.e. by landfill disposal at Wallaroo. The Company has considered and commented at length on various alternatives for treatment of contaminated smelter solid waste, but has concluded that for the Tomago smelter, alternatives to landfill disposal are uneconomical and/or impractical as technology presently stands. Table 5.2 of the E.I.S. shows that when the smelter is fully operational, about 73% (6550 t/y, long term average figure) of the contaminated waste will be spent cathode material. The rest will be residues, dross, sweepings, refuse, dust, etc. from the various smelter operations. These materials contain variable levels of fluoride. Table 5.3 of the E.I.S., reproduced below, shows the make-up of the main (spent cathode) component of the contaminated solid waste. SPENT CATHODE-ANALYSIS
Description Quantity
Cathode Blocks 1727 t/y Carbon Slabs 349 t/y Lining Paste 659 t/y Alumina 119 t/y Refractories 1838 t/y Impregnation reaction product 1836 t/y
SPENT CATHODE ANALYSIS - CONTAMINANTS (weight per cent)
Description Typical Range
Fluoride (as F) 7.5 22.2 Sodium 10.0 18.0 Calcium 0.9 6.4 Aluminium (Total) 7.0 22.2 Iron 0.2 2.0 Sulphur 0.1 0.2 Cyanide (as CN) 0.04 0.5 4
Table 5.3 also shows that while the expected production of spent cathode material will be 6550 t/y for a long term normal operation, a "peak production rate" is estimated at 9650 t/y.
The Company proposes to dispose of the contaminated solid waste on a "campaign" basis, according to the following timetable -
early 1985 1st campaign mid 1986 2nd campaign mid 1988 onwards every 3 months
2.2 Transport to Disposal Site It is proposed that, from undercover storage at the smelter, the waste will be carried by covered 22 tonne trucks to the Wallaroo site, a distanee of about 25 km via the Pacific Highway, Medowie Road and Old Swan Bay Road. Each campaign would involve 40 return trips/day for 3-4 days. 2.3 The Site The Company's original landholding at Wallaroo (Portions 60 and 63), comprises some 293 ha., located on the north side of Old Swan Bay Road and east of the Pacific Highway. The land is timbered and most of it drains north easterly toward Twelve Mile Creek. Slopes are gentle and the E.I.S. indicates that little accumulation of surface run-off occurs. The soils are clay rich. The Company has been active in buying adjoining farm and other properties and it now owns some 450 ha. in two parcels. The main holding, containing the proposed landfill site (see Figure 2) is virtually surrounded by State Forest and private (C.S.R.) forest lands.
2.4 Site Selection
The Wallaroo site was selected by the Company on the basis of certain criteria and studies. The E.I.S. (p.40) lists the following: It was considered essential that the site be located -
outside the Hunter District Water Board catchment area within a reasonable distance from the smelter and accessible by road sufficiently distant from any population centres, or sensitive landuses
Essential characteristics with respect to the site itself were considered to be: a clay stratum of sufficient depth to enable excavation of the disposal cells 5
underlying strata which would prevent leachate from entering surface or groundwater bodies topographically suitable and sufficiently elevated to prevent inundation of the cells by surface or groundwater an area of approximately 100 hectares so that a sufficient buffer zone can be established availability for purchase free of any encumbrances which would limit its use for waste disposal
A specific geological/topographical study (Reference 3a) identified the Wallaroo district as a generally suitable target area, because of its deep clays, elevation and gentle topography.Two specific sites were identified in the EIS as potentially suitable for a landfill operation; further study indicated that, subject to confirmation of geology, the proposed site (i.e. site 1 identified on Figure 4.1 of the E.l.S.) was the more suitable. More detailed geotechnical and geochemical studies of it were carried out (See References 3b, 3c, 6, 7, 8, 10). The results of some of these led the Company, in mid-1984, to relocate the actual disposal site and to modify the design of the disposal cells.
2.5 Method of Disposal
The proposal in its present form (i.e. modified design) involves the clearing of vegetation in the selected area and excavation, as required, of clay pits, probably some 8-10m wide, 50-60m long and 5m deep. Waste would be tipped directly into a pit from the transport trucks. In construction, the pit base would be ripped, graded and recompacted to reduce permeability. A leachate sump, accessible by an inspection/withdrawal standpipe, would be built into each pit base. Ripping and recompaction of the cell base, and installation of a sump and standpipe, were the main redesign changes referred to above. A pit would contain a depth of about 3m of compacted waste.
A surface scraping from around the pit would be used to top the waste in the pit and the whole covered with clay and compacted. The finished surface would be mounded about im high to shed water and topdressed and revegetated. A waste disposal campaign would be carried out only in dry weather, and each campaign would affect about 3/4 ha. and involve about 9 days activity on-site, in preparation, filling and covering of the cells. in the present design, the disposal (primary) site containing the cells covers some 25ha. The original proposal presented in the E.I.S. showed a square site of 36 ha. As a result of the Company's investigations of groundwater at the original location in early 1984, the proposed disposal site was shifted further to the south east (see Figure 2). in a supplementary report (Reference 4) the Company recogniSeS the possibility that at a future stage it might wish to reclaim at least some of the buried wastes for reprocessing, and indicates that the proposed disposal method would facilitate reclamation, if that becomes economically viable. 6
3 THE EXISTING ENVIRONMENT
3.1 General
The dominant physical features of the Wallaroo area, south and east of the Pacific Highway, are gently undulating terrain, extensive clay soils and very wide coverage of thick dry schlerophyll forest. The Wallaroo area is generally drained by Twelve Mile Creek, which runs south easterly to the head of Big Swan Bay, the most western part of Port Stephens. The estuarine reaches of the creek are bordered by extensive wetlands. Large parts of the area are covered by the Wallaroo and Medowie State Forests and private forest holdings of C.S.R. Small scale farming and grazing lands are scattered in more favourable locations throughout. Big Swan Bay contains a number of oyster farms.
The Company's main holding is essentially undeveloped, but has been used in the past for periodic logging and rough grazing. Regular burning appears to have occurred. The State Forests in the district are used from time to time for Army training exercises. Freehold land in the area, south west of the Company's original holding, is mainly used for hobby farms and cattle grazing. The Company has now bought most of this land (See Figure 2).
3.2 Surface Drainage
The larger part of the Company's land, including the proposed disposal site, drains generally north east into Twelve Mile Creek. The western part of the land drains south west into Nine Mile Creek, which flows into Grahamstown Reservoir. The reservoir, which is Newcastle's major water supply, is about 5-6 km (direct) south west of the land (see Figure 1). The western boundary of the proposed disposal site is about 500m inside the main Twelve Mile Creek catchment, that is, about 500m from the surface watershed between the Twelve Mile Creek and Nine Mile Creek systems. The southern boundary of the site is just north of the divide between Twelve Mile Creek and one of its main tributaries, Pipeclay Creek.
3.3 Flora, Fauna, Archaeology
The Company commissioned an ecological survey of the main property, with particular emphasis on the disposal area. The E.I.S. (Appendix 2) presents a listing of plant species known to occur in the area, and also listings of mammals, reptiles and birds (E.I.S. Appendix 3) that are known or expected to occur there. Most of the vegetation on the Company's property is dry schierophyll forest, of Angophora -Bloodwood - Peppermint type, of generally uniform age, and with a dense shrub layer in parts. Creek lines on the northern side of the land feature limited wetland vegetation. The 25 ha. disposal site carries the dominant Angophora-Bloodwood-Peppermint forest, a type which the survey showed to be common throughout the district and elsewhere. The faunal surveys indicated that there was not a great deal of species diversity in the area and that no rare or endangered species were evident or expected to occur. 7
The Company corn missioned an archaeological survey and consultation with relevant aboriginal people. No sites of archaeological or cultural interest were found.
3.4 Noise The E.I.S. presents the results of a baseline noise survey carried out to determine potential local noise effects of the proposed operations on-site and along the immediate access roads (Pacific Highway, Medowie Road and Old Swan Bay Road). The E.I.S. provides results of background noise monitoring surveys undertaken at one location (i.e. location D, E.I.S. Figure 6.6) which was considered representative of the three residences along Old Swan Bay Road. The survey indicated daylight noise levels of 30.5 to 40.5 dB(A) with peaks up to 83 dB(A) resulting from vehicles and aircraft used in Army training movements.
3.5 Meteorology The E.I.S. presents meteorological data relevant to the area, and notes the absence of any relevant air quality data.
3.6 Subsurface Character of Disposal Site Because of the nature of the proposed landfill operation, and the potential solubility of the contaminant chemicals in the waste, a good deal of the site investigation carried out by the Company relates to the subsurface characteristics of the site, i.e. the nature and extent of the soils (permeability, depth and ability to 'fix' and degrade chemicals), and the occurrence and movement of groundwater. Accounts of various studies carried out, and of the results thereof, are provided by the Company in the E.I.S. and in several supplementary statements. These are listed below. (For full details see References).
Summary of Environmental Impact Statement for a Solid Waste Disposal Site at Wallaroo.
Volume of reports for preparation of an Environmental Impact Statement on proposed waste disposal site at Wallaroo:
C.F.K. Diessel. Geological Investigations. 1980.
Coffey and Partners Pty Ltd Geotechincal Investigation. 1981.
C. Colder Associates. Geotechnical Investigation. 1983.
J.M.C. Atkins. Acoustical Effects Statement. 1983.
G. Bartrim. Study of Flora and Fauna.
f. M. Dallas and S. Greer. An Archaeological Survey. 1983. [:1
Supplementary Information on a Development Application for a Solid Waste Disposal Facility at Wallaroo. 1983. Update on the Proposed Secure Landfill at Wallaroo. 1984.
Supplementary Information Geotechnical & Groundwater Investigation Solid Waste Disposal Area Wallaroo, NSW (Golder Associates, 1984). Geotechnical & Groundwater Investigation Proposed Solid Waste Disposal Facility Wallaroo, N.S.W. Volume Interpretive Report (Golder Associates, 1984). Geotechnical and Groundwater Investigation Vol. 2 Factual Information (Golder Associates, 1984). Potential behaviour of fluoride and cyanide in clay materials and significance for waste landfill design at Wallaroo (M.J. Knight, 1984). Mineralogy and Preliminary Fluoride Adsorption Testing of Clays from Wallaroo, New South Wales (M.J. Knight, July, 1984 and Revision, October, 1984). These statements present, among other things, the Company's evidence for occurrence at the disposal site of deep clay strata of low permeability, and a low level groundwater condition which has a "slow flow" inclination towards the east or north east. However, these conclusions by the Company about soil and groundwater are not undisputed. The Hunter District Water Board in particular has carried out work which leads it to query them. As mentioned earlier in Section 2.4, the Company has moved the proposed disposal site south east from its original location. This was a consequence of much higher rises in groundwater (following heavy rain in late 1983 and early 1984) than had been predicted from the original site studies. As part of ongoing site investigations, the Company in October 1984, dug a large 'trial' cell at the proposed disposal site and installed groundwater monitoring arrangements. 9
4 PROPOSED DESIGN AND OPERATIONAL SAFEGUARDS The main elements of the proposal, as presented in the E.I.S. and the Company's 'update' report of August 1984 (Reference 5) are outlined in the foregoing Section 2. The 'update' report identifies the following proposed safeguards, relating to water quality and conditions. The E.I.S. identifies the following factors which will operate and safeguards which were or are to be applied to minimise environmental impacts of the proposed operation. 4.1 Water Quality and Conditions The Company's 'update' report lists (in two schedules) 17 design, operational and other factors which it considers will prevent adverse effects in relation to water. These are summarised below-
QQIIthL.tJ 1 Diversion of surface water run-off around the disposal area 2 Compact sealing of cells and local contouring to minimise surface water infiltration 3 Location of cells in deep (c. 25m) clay of "low permeability" with their bases at least 5m above "the predicted maximum" water table
4 Ripping and recompaction of cell base to create a "much lower permeability zone", grading of the cell base and incorporation of a sump for collection and removal of any leachate which might form
5 Certification by an experienced and qualified professional that each pit has been properly constructed to approved specifications in suitable clay
6 Provision of a leachate monitoring and withdrawal standpipe in each cell sump
7 "The rapid and strong adsorption characteristics of the Wallaroo clays which would restrict the rate of movement of pollutants to a minute fraction"
8 "The massive adsorption capacity of the clay which will enable it to retain far more of the pollutants than is ever likely to escape"
9 Revegetation of the site to minimise erosion and rainwater infiltration
Si&eRun-Off 1 Direct disposal of waste 2-5 m below ground surface and placement of w a s t e only in d r y weather 10
2 Covering and cleaning of waste transport trucks; trucks will not enter pits
3 Cleaning of any waste spillage and scraping of surface surrounds into cells
4 Checking and cleaning of compaction equipment
5 Collection of all surface water run-off from the active disposal area in a dam, with monitoring and use of dam water for revegetation on-site 6 On-site supervision of operations by the Company 7 Monitoring of surface water leaving the site to ensure compliance with (State Pollution Control Commission) licence conditions
8 "Massive dilution effects" which would operate when rainfall was sufficient to produce surface run-off from the Company's land into Twelve Mile Creek
4.2 Noise Trucking and emplacement activities to be carried out - only between 7.00a.m. and 5.00p.m. on weekdays temporary earthwork noise shields to be erected on the - west side of each cell
4.3 Air Pollution (Dust) The E.I.S. (P53) states "Experience has indicated that the material will be sufficiently moist to prevent dust emissions during handling and transport"
stockpile heights of excavated material to be limited progressive revegetation to be carried out with only a small area of land stripped at any one time
sections of Old Swan Bay Road to be sealed
truck loads of waste to be fully covered en-route between the smelter and the site
waste to be tipped directly into cells
waste in cell to be compacted in a single operation
4.4 General Proposed trucking operations are limited to a total of 12-16 days/year
waste materials produce no odour or gas contaminants 11
operational procedures will avoid contamination of truck undersides
trucks and compaction equipment will be cleaned on site after tipping, with waste residues going into cells
all disposal operations will be supervised on site by the Company's environmental staff the Company will develop a program for monitoring air, noise, water and other environmental factors; dust conditions (fallout) and vegetation will be sampled regularly 4.5 Monitoring In its 'supplementary information' report (p. 22), the Company indicates that it will develop a monitoring program in association with the relevant authorities before commencement of any landfill operation, that all monitoring data will be regularly provided to the State Pollution Control Commission and that the program will include the following:
Groundwater levels and quality Surface water quality
Air quality
Vegetation
Soil
Rainfall
Noise levels
Waste quality 12
5 REVIEW OF SUBMISSIONS
5.1 Private Submissions
Port Stephens Shire Council advertised and publicly exhibited the proposal and the E.I.S. and invited submissions to be made to it.
Seventy three (73) submissions were received. One was a multiple signature petition, organised by the Raymond Terrace Public School - Infants Department, signed by two hundred and ten (210) persons. The names of persons and community organisations who lodged individual submissions are listed in Appendix 1. The comments made, and concerns and issues raised in these submissions can be summarised as follows:
1 More research and study needed of whether wastes could be used (including recycled) instead of dumped
2 Impact on fauna, especially bees 3 Alienation of a State Forest
4 Impact of contaminated run-off on a swamp, Big Swan Bay, Port Stephens, and Twelve Mile and Pipeclay Creeks
5 Pollution of soils (intractable and long term)
6 Limited local employment benefits
7 No indication in E.I.S. of amount and composiiton of wastes other than spent cathodes
8 Impact on local farming
9 Impact on local forestry
10 Impact on local oyster farming (Big Swan Bay)
11 Impact on drinking water quality (via Grahamstown Reservoir and Balickera Canal) 12 The Company should be prepared to spend more money on environmentally safe disposal of waste 13 Insufficient information in the E.I.S. as to what will happen when the smelter ceases to operate, i.e. what will be the ultimate use of the site and potential impact on public finances
14 The impact of leachate on groundwater must be established before development consent is granted; it may be too late once contaminants are discovered in the water 13
15 Insufficient information is given in the E.I.S. relating to the direction of flow of groundwater at the site; this is important if it reaches the wastes
16 The E.I.S. may have underestimated the height of the water table (measured following a drought); it is therefore still possible that groundwater may reach the wastes 17 There has not been adequate investigation (absence of a geochemical report) of the ability of the clay strata to retain fluorides and cyanides
18 The approving authority for the proposal should not be Port Stephens Shire Council 19 The proposed fencing is not adequate to keep children off the site; to make the site safe, a full-time caretaker would be needed 20 The relevance of forthcoming State legislation on environmentally hazardous wastes has not been referred to 21 The possibility of using any existing and forthcoming alternative toxic waste dumps has not been adequately explored in the E.I.S.: sites do not have to be within Port Stephens Shire 22 Large adverse effects could occur if certain types of accidents or intentional acts of sabotage (e.g. during war time) occurred
23 Impact on nearby residential activities 24 Impacts due to truck movements (including road safety aspects) will be higher than stated in the E.I.S.
25 Impact on flora and fauna conservation
26 Adequate time should be given for individuals, groups and public authorities to prepare objections on the proposal
27 Air pollution; contaminated (dust) impact on, e.g. homes, schools, vehicles and the Pacific Highway, domestic water tanks, dams and crops, water bodies and forest vegetation
28 Inadequate E.I.S., no emergency plan is stated for remedying any accidents (including overturning that may occur with trucks carrying the toxic wastes to the tip
29 No discussion of the likely event that trucks will be washed with water following delivery of wastes, and where this would happen
30 Noise pollution, truck movements, earthmoving plant and waste dumping operations 14
31 This site might be later extended to collect toxic wastes from other industries
32 No consultation with the State Fisheries Division of the Department of Agriculture; possible impact on fishing activities
33 General impact on all the residents in Port Stephens Shire (Hunter Region)
34 General adequacy of the E.I.S. 35 Inadequate E.I.S.; appropriate measures to mitigate the environmental impact (including treatment of any permeable zones) were not stated
36 Impracticality of backfilling operation in the event of rain falling during the dumping operation
37 Possible impact of water pollution on the tourism industry in Port Stephens Shire
38 Possible impact on the proposed dump of the nearby RAAF Base Bombing Range
5.2 State Government Agency Submissions in carrying out its examination of the proposal, the Department sought and obtained the views of a number of State Government agencies. Those views are set out in the following:
The Department advised that the toxic effects of cyanide are highly acute, but would be broken down in several weeks or less. Consequently, damage to aquatic life would only occur for a short period following the discharge of a slug of cyanide contaminant it such were to occur. Fluoride, however, can cause chronic sub- lethal effects on marine life if sufficient concentrations persist. The Department pointed out that no details are given in the E.I.S. on the importance of the oyster industry in Big Swan Bay nor of possible adverse effects of leachates containing high concentrations of cyanide and fluoride on oyster cultivation. It considered it to be unfortunate that the selected site is within the catchment of a major waterway, and indicated that an alternative site draining to a non oyster producing area would be more acceptable. The Department expressed concern on behalf of the Oyster Farmers Association about the possibility of human error in operation of the disposal site, and non conformity with safeguards. In its original submission and in further advice, the Department requested that a number of specific conditions relating to procedure and design be attached to any consent given for the development, that provision be made for suspension of dumping of wastes if concentrations of pollutants exceed permissible limits and that there be arrangements for payment of compensation to affected oyster farmers in the event of oyster cultivation being adversely affected by pollutants emanating from the disposal site. 15
WOM The Service responded to a specific question which had been raised about the possible effect of the development on a remnant stand of rainforest somewhere east of the Company's land. The Service indicated that there is no rainforest on the site or adjacent to it and the only rainforest it knows of in the district are occurrences rigidly confined to the immediate vicinity of perennial streams. It considered, providing leachate was confined to the disposal site, that these 'gallery' rainforest stands in the area would not be affected.
The Commission considered that production of leachate from the disposal site was likely and that it would be possible for it to reach groundwater, with potential for contamination of Grahamstown Reservoir. It considered that the Company had not adequately demonstrated that more appropriate alternative sites are unavailable. Further, it considered the EIS does not demonstrate that the proposed safeguards would be adequate to protect the Hunter District Water Board's water supply system. The Commission also considered that a wider range of alternative sites might be examined. In December 1984, the Commission advised the Department that following its examination of the Company's modifications of the proposal, it still had a number of concerns about the possible pollution of groundwater by seepage of toxic material from the disposal site.
Hunt ej flflQg The Board drew the attention of Port Stephens Shire Council to the 1 Waste a ndPlluti idiiy1Lontm itt e e report. This had identified 11 sites, including the Wallaroo site, as being suited to disposal of solid and liquid (including toxic) waste within the Lower Hunter. a1ntQLMi1LIIQ The Department raised no objection to the proposal but considered that the Company should seal a short length of Main Road 518, i.e.Medowie Road. Department of Mineral Resourcea The Department raised no objection to the proposal but indicated its interest in a number of matters. It felt that sufficient consideration had not been given to other areas which were geologically suitable for the proposed waste disposal facility. state in November 1983, the Commission made a submission to Port Stephens Shire Council on the proposal as set out in the E.I.S. 16
The Commission recommended a number of conditions, relating mainly to long term monitoring and security of the disposal site, generally supported the Company's proposals, and expressed a view that there was no potential for adverse impacts which would warrant a refusal of the proposed development.
In September, 1984, the Commission advised the Department of its views on the 'update' report by the Company, which presented a modified design and location for the disposal cells. The Comission concluded, as before, that if the disposal site was designed and operated as proposed by the Company, any likelihood of pollution by leachate migration from it was acceptably minimal.
The full text of the Commission's advice to the Department is presented in Appendix 3.
r Bj
The Board occupies a particular position among those who made submissions on the proposal, in that it commissioned a special technical review of the work which had been carried out by the Company, especially in relation to the groundwater characteristics of the disposal site. The Board's concern arose because the disposal site is not far outside the catchment boundary of the Grahamstown Reservoir, and because its own experience with groundwater has shown the difficulties of modelling and prediction in that field. At an early stage, in the absence of a detailed site survey, there was some question raised of uncertainty about the precise location of the catchment boundary. That question was resolved by a contour survey carried out by the Company which confirmed that all surface drainage from the disposal site was to the north east, i.e. toward Twelve Mile Creek. However, the characteristics of groundwater are less easy to determine, and the technical work commissioned by the Board (Reference 14) leads it to question whether the Company's investigations have provided sufficient proof of the security of the proposal in terms of potential pollution of groundwater and especially, groundwater which might eventually find its way into Grahamstown Reservoir. In its report titled Proposed Solid Waste Disposal - Wallaroo (Reference 11), the Board comments on overseas practice in relation to disposal of smelter potlining, and lists the following conclusions and views about the study results presented by the Company for the Wallaroo site:
the Company's conclusions about groundwater conditions and behaviour are questionable
modelling of water table levels on short term data as the Company has done will yield incorrect results
some groundwater flow at the disposal site is toward the west, i.e. toward the Grahamstown Reservoir catchment 17
the possible effect of the waste minerals on the clay cell base is an unknown
laboratory results (in fixation and breakdown of chemicals in soils, and in movement of fluorides through clay) cannot be guaranteed under field conditions, where conditions are variable
most North American smelters pretreat cyanide/fluoride leachate to remove the toxic materials before disposal
the Company's conclusion that the clays at the proposed disposal site are of generally uniform low permeability are not supported by the data provided there are several fault lines in and around the disposal area and these are directed toward Grahamstown Reservoir In the opinion of the Board, as set out in its report, the Company has not proven the long term security of the site as a hazardous waste dump, and the technical work undertaken by the Company so far is neither sufficient nor conclusive for such proof. The Board's special concern is with the possiblity of 'leakage' of cyanides from the disposal site, and it has presented the following views and recommendations to the Department: The Board objects to the establishment of a waste dump for the disposal of wastes containing cyanides and cyanide compounds at Wallaroo.
The Board has no objection to the establishment of a waste dump for the disposal of wastes (not containing cyanides or cyanide compounds) at Wallaroo subject to the following conditions: The supervision of disposal, monitoring etc. is to be undertaken by an independent body. Leachate treatment facilities are to be provided at the site of disposal. This is for the leachate that could be collected at the bottom of the pit.
The monitoring of the contaminant movement is to be undertaken within the Vadose zone using suction lysimeters. The number and location of monitoring points is to be decided on geological information available in relation to the disposal pits. These are in addition to the usual groundwater monitoring. The frequency of monitoring should depend on the results obtained.
18
4. An alternative disposal strategy must be stipulated that could be adopted in the event of something going wrong with the proposed site.
5. Various tracer movement studies are to be undertaken either in test pits or in the actual disposal pits to verify the results obtained under laboratory conditions. These studies are to identify the various zones of infiltration or paths of contaminants around the disposal area if any, the time of travel of a wetted front through the consolidated clay layer etc.
6. If the movement of a Iluoride front is clearly identified in the unsaturated regions, the disposal operation is to be reviewed.
7. The Board is to be provided with an indemnity similar to that provided by the Tomago Aluminium Company in relation to fluoride fall out from the smelter.
The Board would review its objections in relation to the disposal of wastes containing cyanides or cyanide compounds provided:
the investigations undertaken at the site prove the suitability and security of the site, to receive waste products containing cyanides, to the satisfaction of the Board;
the following additional requirements of the Board are met (in addition to the requirements 1-7 above).
8. If the movement of a cyanide front is clearly identified in the unsaturated regions the disposal operation is to be stopped.
9. In the event of 118" occurring the disposed waste material is to be removed from the disposal pits along with the contaminated soils for disposal elsewhere.
10. The Board is to be provided with an indemnity to cover the following: Total cost of the removal and alternative disposal of waste material and contaminated soils within the area.
5.3 Port Stephens Shire Council Submission
In a letter of advice to the Director of the Department, the Council expressed its concern about the possible effects of leaching of cyanides or fluorides on the Port Stephens oyster industry. It also requested that the proposed Commission of Inquiry on the proposal give consideration to six particular questions relating to guarantees, compensation, and the responsibilities and resources of Local Government to adequately deal with questions of hazardous chemicals disposal.
The full text of the Shire Council's letter is reproduced in Appendix 2. 19
6 MAIN ISSUES
A review of the comments and advice which have been received, taken together with the Department's own assessment, suggest that the main concerns about adverse environmental impacts of the Company's proposed development can be classified into six groups, as follows:
1 Concerns that the Company has not given adequate consideration to alternative disposal techniques or sites
2 Concerns that the existence of a waste disposal site will have 'depressing' effects on the local economy and amenity
3 Concerns that use of the site will obliterate native fauna and flora
4 Concerns that proposed operational and other safeguards, in relation to matters such as waste transport, materials handling, emergency measures, compensation or indemnity arrangements, will not be adequate to safeguard the public
5 Concerns about the adequacy of site investigations, performance of the disposal site and the efficacy of the design safeguards, especially as regards lack of certainty about possible formation and escape or leachate, water-borne pollutants and their possible destinations. Specific concerns relate mainly to the following:
a possible effects of the chemicals on the permeability of the compacted base seals of the cells
b likelihood of water entering the cells from above and/or below the ground
c likelihood of chemically polluted subsurface water (leachate) escaping from the cells and entering groundwater
d possible destinations of water-borne pollutants
e possible quantities, rates of movement and eventual toxic effects of water-borne pollutants, especially in regard to the Grahamstown Reservoir water supply and the oyster farming industry in Port Stephens
6 Concerns about the long-term safety and security of the facility, in terms of the above, and the availability of effective operational safeguards in the event of long-term leakage from the waste disposal site. 20
7 ASSESSMENT OF ENVIRONMENTAL IMPACT
The concerns which are categorised in the previous Section 6 provide a framework for presenting an assessment, based on present evidence, of the likely environmental impacts or the proposed development.
7.1 Alternative Disposal Methods and Sites
The Company's proposal has produced a body of comment on technology for disposal of contaminated smelter waste, alternative to landfill disposal. The Reynolds Metal Company of North America has been cited as a company which treats all spent potlining so that there is no need for its disposal, either by landfill or other means.
The Company has addressed this issue in some detail (see Reference 15, September 1984) and has advised that operations such as those at Reynolds are both site and company specific and that for the Tomago smelter, salvage and recycling of spent potliner material is, for several reasons, neither practical nor economically viable.
It has pointed out that such processes would require the establishment of a chemical plant at the smelter, that alternative disposal methods would involve their own environmental problems, that the proposed secure landfill is environmentally safe and that this form of disposal is superior in environmental terms to others, e.g. open dumps, which are commonly employed by smelters elsewhere. The Company has indicated that it is participating, and will continue to participate in major research being carried out on the reprocessing of spent potlining, in search of an economically viable and better solution to the problem of contaminated waste disposal.
Lacking information, the Department is not in a position to question the Company's conclusion, that disposal of contaminated solid waste from the smelter by salvage and recycling is at this stage neither practical nor economically viable. It is to be noted that in 1981, when considering the question of waste disposal from the Tomago Smelter (Proposed Tomago Aluminium Smelter, Environmental Impact Assessment Report, pp. 135-137) the Department identified a need for an investigation of salvaging and recycling possibilities, but that the development consent granted for the smelter clearly reflected (in Condition 14) an expectation that the toxic waste products from it would have to be disposed of via secure landfill.
Section 2 of this report outlines the studies which the Company carried out and the criteria which were used in identifying the Wallaroo area as particularly suitable for disposal of the smelter waste, and in selecting the specific site which it did. However, the Department has no evidence on the extent of the Company's search for specific possible sites, or the detailed criteria (if any) which may have been applied. The report by 21
C.F.K. Diessel (Reference 3a) indicates that the search for a site concentrated on "a NE-SW tending belt of terrain." In its 'supplementary information' report (Reference 4, p. 24) the Company indicates that there is no maximum economic transport distance involved, and the Wallaroo area was chosen because it was the closest location to the smelter, which was topographically and geologically suitable for the purpose.
The Department is therefore unable to conclude how rigorous a cearch was made by the Company for alternative disposal sites. It notes however, that a survey by a local government advisory committee (Newcastle Regional Waste and Pollution Advisory Committee, see Reference 17) identified the Wallaroo site as one of a small number in the Lower Hunter considered to be suitable for disposal of toxic waste.
7,2 Effects on Local Economy and Amenity
Concerns have been expressed that the operation and indeed the simple presence of a large waste disposal operation at Wallaroo, would have adverse impacts on the amenity of local residents and a 'depressing' effect on the local economy. These concerns can be distinguished from those that the waste disposal site might become a source of water pollution, with actual adverse effects on e.g. the Port Stephens oyster industry or the Grahamstown Reservoir.
The main effects under this heading are seen to relate to possible disturbance and nuisance from noise and air pollution, and lowered property values arising from some public perception that the waste installation is 'unsafe' or apprehension that it might become 'unsafe' at some future time. The E.I.S. specifically addresses the questions of noise and air pollution.
While recognising and appreciating concerns of this nature, the Department finds it difficult to conclude that they are well founded. The disposal site is in a relatively undeveloped and thinly populated area well removed from the nearest residence. The Company has purchased a large tract of timbered land which is buffered by large belts of State and private forests on three sides. On its other side (i.e. south west, through to the Pacific Highway) the Company has acquired another large tract of property, including all the residences near the access route of Medowie and Old Swan Bay Roads. Tne nearest non-Company owned house is some 2 km from the disposal site.
The disposal site itself will occupy a small cleared area in some thousands of hectares of forest land, and will be well screened from any public view. There seems to be no evidence to suggest that this general situation or land use pattern might significantly change in future. The site is close to the Pacific Highway, reducing the off-highway transport distance to a minimum. Specific measures will be taken to prevent dust and operational noise. For a small number of days each year residents in the few Company owned houses between the disposal site and the Pacific Highway may experience some noise disturbance from heavy trucks passing. 22
The question of possible long-term local attitudes toward a smelter waste disposal operation at Wallaroo is difficult to address. It probably needs to be accepted that, irrespective of any objective evidence that such a facility is likely to have, has, or will have = harmful effects, some members of the community will believe otherwise. Whether local concerns would in fact be translated into, e.g. depressed property values, seems uncertain at this stage. 7.3 Effects on Native Fauna, Flora and Archaeological Relics By and large, few concerns have been expressed that the waste disposal operation would have a significant direct effect on native fauna and flora of the immediate locality. The surveys commissioned by the Company indicated that the dry schierophyll forest on the site is (in type) common and widespread, and has been significantly affected by logging, fire and grazing. Its habitat value appears to be small. The surveys disclosed no rare or threatened plant species and indicated that no rare or endangered fauna are expected to occur or be affected. The Department saw no evidence to the contrary and would agree that effects of this type are unlikely to be significant. A survey by the Company revealed no items of archaeological or aboriginal cultural interest on the land.
7.4 Operational Safeguards A number of concerns have been expressed about the adequacy of the Company's proposals in terms of what may be called operational safeguards. These relate mainly to the following:
transport of waste material from the smelter to Wallaroo, and the possibilty of accidental spillage en-route
the possibility of spillage of material at the disposal site and accidental transport of pollutants from the site, e.g. on trucks the possibility of performance failure, intentional or otherwise, in the carrying out of the disposal operations
the security of the disposal site against interference through trespass or sabotage the lack, in the E.I.S., of consideration of an alternative strategy for disposal of the smelter waste in the event of 'something going wrong' with the operation as proposed
a similar lack of consideration of emergency 'clean up' measures which might be needed in such an event the lack of evidence, in the proposal, of acceptance by the Company of any need for special arrangements for indemnification against claims which might be made in terms of untoward effects of the disposal operation 23
Taking into account the various controls and factors which would apply to the proposed operation, e.g. for pollution control and road transport of toxic materials and the possibilities for additional controls and measures which could be applied, the Department finds it difficult to conclude that these sorts of concerns are in general well founded. As set out in the E.I.S. and outlined in Section 4 of this report, the Company proposes a number of measures, both physical and administrative, which will be applied to ensure security and responsible conduct of its waste disposal operations. The Company, in its 'supplementary information' and 'update' reports (References 4 and 5), has further elaborated on those measures to ensure operational security and site safety. Among these measures it has identified the action which the Company could take to remove buried waste and contaminated soil in the event, which it regards as "highly unlikely" of a disposal cell failing.
On the question of maintenance of the disposal site in the long term future, the Company has suggested that a trust could be established to maintain the area in perpetuity if and when the Company itself ceased to exist. It has undertaken to contribute a certain sum ($3) for each tonne of waste placed, to a fund designed to cover the cost of such long-term maintenance, and has proposed that this contribution be reviewed every 5 years between the Company and the Government. This is a most important aspect of the proposal, since the effective maintenance in perpetuity of the disposal cells will be of critical importance for the long- term security of the site.
On the question of long-term use of the site, after the waste disposal operation has been completed, the Company has indicated a willingness to dedicate the site and a surrounding area to some community requirement, and has suggested that the question of eventual end use be reviewed in ten years time.
The Department would agree that these questions about a waste disposal site in the long-term cannot be decided now, and that provisions for maintenance and end use would have to be worked out over time, that financial arrangements between the Company and Government would need to ensure absolutely effective long- term maintenance of the site, and that in principle, direct ownership of and responsibility for the site should not pass to the public sector.
On the question of insurance and indemnification, the Company in its 'update' report, outlines the very substantial corporate security structure which it has to ensure its ability to meet compensation payments to third parties, in any eases where legal liability might be proved against it. The Company therefore sees no need for the provision of speëific guarantees or insurances. it has also pointed out that the results of the extensive monitoring which it proposes to carry out on and around the site will be made available to any government department or appropriate community group. Hence, '(in the unlikely event that pollutants did produce some external damage", affected parties would have access to those results. 24
The Department's view on this question of mandatory specific guarantees or indemnities is that the position taken by the Company is a reasonable one and that the possibility of untoward effects arising from the waste disposal operation does not seem sufficiently likely to warrant the Company being required, as a condition of development consent, to enter into specific arrangements of that sort. At the same time it is clearly the case that should any such effects arise, the costs of remedying them should in principle be fully borne by the Company, and that arrangements between the Company and Government must guarantee that.
7.5 Performance of the Disposal Site
The Company proposes to dispose of solid contaminated waste in a secure landfill. The bulk of concern rests upon the question of whether the disposal site could or would become a source of pollution by 'leakage', especially in the long-term.
As seen by the Company, the characteristics of the disposal site (deep, low permeability clays of a particular type, low water table etc.), the treatment and design of the surface and disposal cells (contouring, compaction, sumping etc.) and proposed supervision and monitoring arrangements, are all intended to ensure:
a minimum likelihood of contaminated leachate forming in the cells
b detection and removal of any contaminated leachate which might form
c early detection and remedying of any ground pollution which might occur in the vicinity of the cells
The Company has not seen it necessary to propose additional action such as the in-situ addition of powdered limestone and superphosphate to the waste to render its chemical content less soluble and hence less transportable in groundwater, nor pre-treatment of the waste before disposal.
It has proposed continuing investigation of the clays and groundwater at the site, but has made the point that such investigations take time to carry out.
Most concerns expressed about the possible detrimental effects of the proposed operation turn on the concept of leachate, polluted by fluorides and cyanides, forming in the cells and escaping from the disposal site and travelling to Twelve Mile Creek and hence Port Stephens, and/or to Grahamstown Reservoir.
As noted previously, much of the investigation work carried out by the Company has been and is directed to an understanding of the subsurface characteristics of the site, especially the depth and nature of the strata and the position and movement of groundwater in the area. As outlined in Section 5.2, the Hunter Pal
District Water Board, because of its special concern at the possibility of a toxic waste area being sited near the catchment boundary of Grahamstown Reservoir, has itself commissioned professional review of the work done by the Company. That review has led the Board, at this stage, to a view that the Company has not proven the security of the site for hazardous waste disposat, and that the technical work so far undertaken by it is neither sufficient nor conclusive in that regard.
In response to expressed concerns about the possible security of the Grahamstown Reservoir water supply, the Company suggested (Reference 13) consideration of some 'worst case' scenarios.
One scenario was based upon the escape of 10% of all emplaced cyanide (i.e. 360 tonnes emplaced over 20 years; 10% gives 3b tonnes escape). Should this escape occur over a short period ot time and 20% of this find its way to Grahamstown Reservoir, the cyanide concentration in the water would be 0.05 ppm. Should 80% of the escaped cyanide find its way to Port Stephens, the cyanide concentration in Port Stephens would be about 0.02 ppm. Both these levels meet the SPCC's acceptable standards for drinking water.
Another scenario assumed that all cyanide contaminants produced by the smelter in one year are dumped into Grahamstown Reservoir and dissolved in the Reservoir (which would be unlikely). The resultant concentration of cyanide in the Reservoir would be 0.1 ppm i.e. twice the acceptable standard. However, at that level a person would need to consume 100 litres of water in a matter of hours to "obtain an injurious human dose."
A third scenario was based on the event of a truckload of 22 tonnes of cathode waste being discharged directly in Grahamstown Reservoir and all the cyanide being leached from the waste. in this event, the resultant concentration of cyanide in the Reservoir would be 0.00044 ppm. That is, one hundred times this concentration would be required to reach the quality standard for drinking water.
A further scenario assessed the possibility of fluoride movement from the disposal cells, due to vertical leaching of fluoride to an assumed groundwater table 2-10 metres beneath the cells, to Twelve Mile Creek (a tributary of Port Stephens) and Nine Mile Creek (a tributary of Grahamstown Reservoir). This scenario concluded that due to the adsorption of fluorides in the clays, the fluoride movement would be very slow. Knight's report (Reference 10) indicated that even if a cell filled with leachate, and had an uncompacted base it would take some tens or possibly hundreds of years for the fluoride to travel the vertical path to reach the water table; the Company considers (Reference 13,p.19) that thousands of years would be required for fluoride to travel to the point where the water table contacts the ground surface, i.e. where it would enter tributaries. 26
The State Pollution Control Commission has expressed a view (see Appendix 3) that such extreme scenarios are unlikely, but that even if one of them did occur, the amounts of cyanide in the proposed landfill "do not pose any threat to the quality of potable water in Grahamstown Reservoir".
In its 'supplementary information' report, the Company indicates that piezometers are being installed to confirm that groundwater movement at the site is toward the east, i.e. in the same direction as its surface flows. It further indicates that "proven engineering techniques" will be applied, before any waste is buried, to ensure that the direction of groundwater flow beneath all disposal areas is away from the Grahamstown Reservoir catchment. The Company's site investigations and the work of the Hunter District Water Board and other bodies have produced a volume of literature (see References) dealing with the subsurface characteristics of the site and the possiblity of leachate formation and escape from the disposal cells. The material focusses mainly on questions of - groundwater levels and flows permeability of the clays, to groundwater and to soluble chemical contaminants possible chemical interaction between groundwater, chemicals and clays and the possible effect of such interaction on permeability characteristics of the clays to 'fix' fluorides and cyanides likely efficacy of the disposal cell design to ensure no escape of contaminated leachate
adequacy of the investigations to provide a basis for confident prediction of behaviour of the disposal cells
In assessing the proposal, the Department has reviewed this material at some length, considered the various study results and examined other relevant technical literature. It is not considered necessary, or appropriate, that the details of that process be repeated in this report. However, from its work the Department draws the following conclusions:
A significant doubt exists concerning the characteristics of groundwater flows in the area. 27
Because of limited borehole data, short monitoring period and groundwater modelling technique and parameters used, there cannot be absolute certainty that groundwater levels at the disposal site will remain at least lOm below ground surface. There is likewise no absolute certainty that groundwater would never enter the cells.
Che mi&trij No work has been done on local groundwater chemistry. The question of reaction with contaminant chemicals has not been specifically addressed, but would need to be studied as part of the general question of leachate/clay interaction.
Claya The cell disposal concept rests on prerequisites of deep, low permeability clays and the Company's studies which purport to show the 'fluoride fixing' characteristics of the Wallaroo clays, a quality regarded by it as an additional or supplementary safeguard against chemical pollution from the disposal site. At the same time, the Company acknowledges that absolute confirmation of indicative laboratory tests of these clay characteristics could only be obtained by on-site testing.
The Company has also indicated that testing of the Wallaroo clays to demonstrate that they contain naturally occurring micro-organisms capable of destroying cyanides (as distinct from fluorides) is difficult, and would take a long time, even if laboratory investigation proved feasible.
On the question of leachate/clay interaction within the disposal cells, The State Pollution Control Commission (see Appendix 3) notes that clays are relatively unreactive, but that "some increase in the permeability of the clay is possible" particularly if exposed to leachate over a long period. On the assumption, however, that any leachate which might form in the cells is regularly removed, as proposed by the Company, the Commission does not consider it likely that there would be any s i g n i f i c a n t increase in permeability as a result of leachate/clay interaction. The Department's conclusion in respect to these matters, based in part on its own review of overseas studies which provided one basis for the Company's conclusions, is that a significant degree of doubt remains about the likely interactive effects of groundwater, clays and chemical contaminants in the wastes. The Department considers that adequate field tests would be needed to ascertain the probable mobility and biodegradation of the leachate chemicals in the Wallaroo soils. 28
7.6 Summary In summary, the Department would agree that in regard to operational and procedural matters, transport, and noise, the proposed operation is likely to have an acceptably minimum environmental effect. Because of some uncertainties about clays, groundwater and chemicals in the waste, the question of its potential, especially in a long-term, for ground and water pollution via leachate, is not so clear. The Company relies on security of the disposal cells through massive physical buffering of low permeability clays, and a simple physical design of the cells to eliminate leachate formation and escape, with added safeguards from fixation of fluoride and cyanide biodegradation in the clay soils. Some doubts remain about some of these factors.
The Company has undertaken to continue site testing and monitoring to guarantee that the procedural and design specifications for the operation are strictly adhered to to make monitoring results available to Government
to halt disposal operations if necessary to carry out any 'clean up' operation which might be needed if ground pollution occurs to guarantee a satisfactory demonstration, prior to disposal of waste in any cell, that natural movement of groundwater beneath that cell is directed away from Grahamstown Reservoir to fund the costs of monitoring and (possible) long- term management arrangements for the site to meet the cost of any proven claims arising from untoward effects of the operation to continue to support research and developmental work on alternate technology for smelter waste disposal
The Australian Environment Council in its report Management and Disposal of Hazardous Industrial Wastes, Report No. 9, 1983 (Reference 12) recommends that highly toxic inorganics (cyanides) are not suitable for landfill without some form of pre- treatment. Some evidence (Reference 11, p ii) has been submitted that the disposal of potliningS as proposed by the Company would not now be acceptable in North America without some form of pre- treatment to render their contaminants innoccuouS. 29
The Company has specifically refuted this suggestion and claims that the proposed Wallaroo operation would qualify under the relevant (US) Environment Protection Agency regulations (Reference 15, September 1984).
The State Pollution Control Commission, having examined the proposal (both as regards the original and current proposed disposal sites), has concluded that while there is a possibility of geotechnical assessments and forecasts proving to be inaccurate, the design of the proposal, the nature of the Wallaroo clays and the intended safeguards are such that the likelihood of any pollution risk from the disposal site would be acceptably minimal. On the other hand, a number of parties, including the Department of Agriculture, the Water Resources Commission and the Hunter District Water Board have expressed doubts about the evidence to date that the facility would be secure against pollution leakage, especially in the long-term. Of these, the Department has proposed a number of 'safeguard' conditions; the Commission has concluded that further tests and design reviews are needed. Because of the toxicity of cyanides and the proximity of the site to the Grahamstown Reservoir catchment, the Hunter District Water Board has taken a position of:
a objecting to disposal at the site of wastes containing cyanides
b not objecting to the disposal of wastes free from cyanides, subject to specific conditions for supervision, monitoring, leachate treatment, 'clean up' operations, on-site tracer movement studies, review of the operation if fluoride pollution occurs and indemnification of the Board against pollution effects
c being willing to review its objections in relation to the disposal of cyanide contaminated waste, subject to
site investigations proving, to the Board's satisfaction, the suitability and security of the site to receive cyanide contaminated waste
2 in addition to the conditions in (b) above, conditions that disposal is to cease if cyanide pollution is detected, and in that event, a 'clean up' operation is to be undertaken and the Board to be indemnified against the cost of such an operation The more cautious approach adopted by the Hunter District Water Board arises from the uncertainties which are still seen to exist as regards the movement of groundwater in the waste disposal area, and the Board's need to guarantee absolute security of the Grahamstown Reservoir against any possiblity of its being affected by pollution (at least by cyanides) from the disposal site. 30
The Board's view that no approval should be given at this stage to disposal at Wallaroo of wastes containing cyanides (i.e. spent cathode material) raises at least two points for consideration. The first is one of practically. Although, as indicated in the E.I.S., the first potline demolition at the smelter is scheduled for mid 1985, it is expected that, barring any unforeseen breakdown in its operation, only a small amount of potline waste will be generated before 1988. Beyond that, spent potlining will comprise over 2/3 of the total contaminated waste stream, but it does appear that for the first few years at least, the spent cathode output might be satisfactorily stored pending a final decision on its disposal at Wallaroo (or elsewhere) Suitable arrangements for any interim storage would need to be made.
The second point is one of logic. If it were to be accepted that a reasonable doubt exists as regards the security of the proposed landfill in relation to possible groundwater flows from the site to Grahamstown Reservoir, it follows that a similar doubt must exist in relation to possible groundwater flows elsewhere, e.g. to Twelve Mile Creek and hence to Port Stephens. 31
8 CONCLUSIONS AND RECOMMENDATIONS
This report has outlined the Company's proposals, as presented in the E.I.S. and a number of supplementary documents, and reviewed the submissions made and views expressed on it. The Department's assessment has involved consideration of the technical work which has been carried out in development and examination of the proposal, and other technical work of relevance.
8.1 Conclusions
The Department recognises the general undesirability of disposing 01 toxic inorganics in landfill without some pre-treatment. The issue of designing and regulating landfills for the disposal of hazardous waste is beset with difficulties, and experience overseas provides ample evidence of intractable problems which may arise with this type of facility, even when the landfill is sophisticated in design and management arrangements are theoretically adequate.
On the information available, the Department is not in a position to accept or reject the proposition that at this stage, and for the foreseeable future, disposal to secure landfill is the only practical and economical solution available to the Company for disposal of the contaminated smelter waste. It is accepted that the Company is and will be actively pursuing other alternatives which may become available and be economically suited to the Tomago operation, both for disposal of waste and for reclamation of raw materials from it. It is the Department's view, as it was in 1981, when the Tomago Aluminium Smelter proposal was under consideration, that the question of smelter waste disposal in the Lower Hunter is a matter which demands thorough investigation, especially as regards the possibilities for combined salvage and recycling operations. Any such investigation could only be fully effective as a co-operative exercise between the smelting companies and Government.
The Department believes that should approval be given to the Company's proposal at this stage, it should be subject not only to performance conditions, but to also be specifically limited in time, so that at the end of a period of say, ten years, the operation generally and the application of conditions to it, could be formally reviewed in the light of experience. It is noted tht the Company has suggested that a review of the question of long-term use of the disposal area could appropriately be carried out in ten years time. The Department recognises that technological developments are occurring in respect of the disposal of potentially hazardous materials; a review in 10 years may appropriately account for such developments and their application to the disposal of smelter waste in the Lower Hunter. The Department recognises that no advance forecasts can ever be guaranteed 100% accurate, and that the provision of adequate guarantees for maintenance of the waste disposal site into the future, and for the carrying out of 'clean up' measures it anything 'goes wrong' with the site, are absolute requirements in this situation. The Department believes that the Company must guarantee these necessary provisions and should be required to stipulate an alternative strategy, at least in principle, for waste disposal if such a situation eventuated.
The Company proposes to establish a trust fund for the maintenance and monitoring of the disposal site in the long-term future. The Department considers that in addition to such a measure, any approval given to the proposal should ensure the establishment of a performance bond which would be available to Government in the event, however unlikely it might be, of any contingency involving public cost. On the other hand the Department has difficulty in accepting the suggestions that have been made concerning special indemnities by the Company of various parties, e.g. the Hunter District Water Board and the Port Stephens oyster farmers. At this stage, it would not see any reasonable grounds for such a requirement being made mandatory on the Company as a condition of development consent.
The Department concludes that the various operations involved in transporting the waste material, in clearing the site, and in excavating, filling and sealing a disposal cell, if carried out as proposed, under appropriate supervision, and in accordance with statutory requirements, are unlikely to result in significant environmental impacts, and that the 'above ground' security and maintenace measures proposed by the Company are likely to be adequate.
However, the Department believes that at this stage there is a less than desirable degree of certainty about the subsurface characteristics of the disposal site, and the likely long-term performance and proof against 'leakage' of the waste disposal cells. On the evidence presently available, the Department is not able to definitely conclude that the proposed landfill would have insignificant or minimal environmental effects in that regard. The Department recognises the special circumstances which exist, firstly that the proposed waste disposal site is situated in proximity to the catchment boundary of a major urban water supply reservoir and secondly, that the site drains to Big Swan Bay, which is a productive estuarine area. While respecting the professional expertise involved in the development of the proposal and comments made on it, the Department is of the view that these circumstances and especially the first, demand further evidence of the likely security of the proposed disposal cells over and beyond that which has yet been provided. It believes that the Company might have more fully considered these circumstances and their likely significance in its selection of a disposal site. 33
The special concern of the Hunter District Water Board relates to Grahamstown Reservoir and cyanides, but the Department recognises that the doubts expressed by the Board about the present evidence for long-term security of the disposal site also raise a doubt about the possibility of both cyanide and fluoride movement to groundwater affecting Twelve Mile Creek. The Department is aware of some evidence for, and of dispute about, the biodegradable nature of cyanides in soils and water.
The Department recognises a number of practicalities which apply to such a proposal, irrespective of where it might be located. One is that the long-term security of the proposed landfill against 'leakaget may be disproved by tests or events, but cannot be conclusively proved in advance by any means. Another is that short-term studies e.g. of soils and groundwater, can provide indicative results, but cannot absolutely demonstrate the long-term performance of the proposed facility. A third is that demonstration of 'proof of security' of such an operation can be obtained in the most reliable form only from 'on-site' trials and monitoring over time.
8.2 Recommendations
Questions raised by the Company's proposal are complex and are in some cases imponderable. Taking all of these various considerations into account, the Department at this stage concludes that the proposal to dispose of smelter waste at Wallaroo could reasonably be allowed to proceed on a controlled trial basis, subject to two broad sets of requirements. The first of these would apply to the operation generally. The second would place an onus on the Company to provide more satisfactory 'proof of security' of the proposed landfill operation within a short term (e.g. 3-4 years) and on the basis of a limited operation, before the proposal proceeded at full scale.
On the basis of the foregoing, the Department would recommend that the proposal by Tomago Aluminium Company Pty. Ltd. to dispose of contaminated solid smelter waste by landfill at Wallaroo, as described in the E.I.S. and modified by the Company's 'update' report of August 1984, be approved for a period of ten (10) years and be liable to formal review prior to the end of that time, and that such approval be subject to the conditions listed 1 to 8 in the following. The Department notes that in the event of approval for the project being granted, additional conditions relating to details of design and procedure may appropriately be attached to such approval.
That, within a period of 4 years from the date of approval, or such lesser period as may be determined by agreement between the Company, the Hunter District Water Board and the State Pollution Control Commission, the Company meet the requirements of the Board and the Commission with respect to studies, and the results of such studies, relating to the disposal site and performance of the disposal cells. 34
2 That within such period referred to in 1 above, disposal at the site of wastes containing cyanides and cyano complexes not be permitted, other than that, which by agreement between the Company, the Hunter District Water Board and the State Pollution Control Commission may be required for the purposes of the tests and studies referred to.
3 That in the event of dispute arising in respect of these matters referred to in 1 and 2 above, the Minister for Planning and Environment shall arbitrate and the Minister's decision shall be final.
4 That on-site supervision of the waste disposal operations be carried out to the satisfaction of the State Pollution Control Commission; the Commission to be given such forward notice as it requires of the undertaking of any waste disposal.
5 That the requirements of the State Pollution Control Commission be met by the Company in respect of -
a monitoring and testing for the purposes of forecasting and detecting pollution at, and from the disposal site
b detections of leachate in cells and removal, handling, storage and treatment of any leachate taken from the disposal cells
c detection of leachate and/or pollution, and the carrying out of remedial or 'clean up' operations if required, and in such event, handling, storage procedure, transport and disposal of contaminated material
d procedure, handling, storage and transport of contaminated material in the event of its retrieval for reclamation purposes.
6 That the Company establish a Trust Fund to be administered by Port Stephens Shire Council to meet any public costs of any monitoring, testing, treatment, 'clean up' and long term maintenance of the disposal site as may be required.
7 That the Company nominate to the satisfaction of the Minister for Planning and Environment, and within a period of two (2) years of any approval granted, of an 'in principle' alternative strategy for disposal of the smelter contaminated solid waste in the event of the closure of the secure landfill operation. 35
8 That the Company establish a Bank Guarantee for $250,000 in favour of the Minister for Planning and Environment, to be held as a performance bond.
9 That the Company actively investigate alternative means of disposal, re-use and detoxification of wastes and provide annual reports of such investigations to the Department of Environment and Planning and the State Pollution Control Commission. 36
REFERENCES
1 Environmental Impact Statement For a Solid Waste Disposal Site at Wallaroo, N.S.W. (Tomago Aluminium Company Pty. Ltd., August 1983)
2 Summary of Environmental Impact Statement For a Solid Waste Disposal Site at Wallaroo, N.S.W. (Tomago Aluminium Company Pty. Ltd., undated)
3 Volume of reports corn missioned by Tomago Aluminium Company Pty. Ltd. for preparation of an Environmental Impact Statement on proposed waste disposal site at Wallaroo, N.S.W. (undated) C.F.K. Diessel. Geological Investigations. November 1980 Coffey and Partners Pty. Ltd. Geotechnical Investigation. February, 1981
C. Golder Associates. Geotechnical Investigation. March, 1983 J.M.C. Atkins. Acoustical Effects Statement. May, 1983 G. Bartrim. Study of Flora and Fauna. (undated)
M. Dallas and S. Greer. An Archaeological Survey. May, 1983
4 Supplementary Information on a Development Application for a Solid Waste Disposal Facility at Wallaroo (Tomago Aluminium Company Pty. Ltd., December 1983)
5 Update on the Proposed Secure Landfill at Wallaroo (Tomago Aluminium Company Pty. Ltd., August 1984)
6 Supplementary Information Geotechnical & Groundwater Investigation Solid Waste Disposal Area Wallaroo, N.S.W. (Golder Associates, January 1984)
7 Volume 2 - Factual Information Geotechnical and Groundwater Investigation Proposed Solid Waste Disposal Site (Golder Associates, June, 1984)
8 Geotechnical & Groundwater Investigation Proposed Solid Waste Disposal Facility Wallaroo, N.S.W. Volume 1 lnterpretive Report (Golder Associates, July 1984)
9 Potential behaviour of fluoride and cyanide in clay materials and significance for waste landfill design at Wallaroo (Knight, February, 19 84 ) 37
10 Mineralogy and Preliminary Fluoride Adsorption Testing of Clays from Wallaroo, New South Wales (M.J. Knight, July 1984 and Revision, October, 1984)
11 Proposed Solid Waste Disposal, Wallaroo, Board's Response to the Department of Environment and Planning (Hunter District Water Board, September 1984)
12 Management and Disposal of Hazardous Industrial Wastes, Report No. 9, Australian Environment Council, 1983
13 Tomago Aluminium Company Pty Ltd submission to Department of Environment and Planning on Proposed Secure Landfill at Wallaroo, 18 September, 1984
14 Review of Proposed Solid Waste Disposal - Wallaroo. Report to Hunter District Water Board (Australian Groundwater Consultants Pty. Ltd., January 1984)
15 Submissions to the Department of Environment and Planning by Tomago Aluminium Company Pty. Ltd. July, September, October, 1984
16 Proposed Tomago Aluminium Smelter, Environmental Impact Assessment, Department of Environment and Planning, 1981.
17 Assessment of Potential Liquid Waste Disposal Sites in the Hunter Region. Report to Newcastle Regional Waste and Pollution Advisory Committee (Resource Planning, July 1983) 38
APPENDIX 1
List of Persons and Community Organisations who made Individual Submissions on E.I.S.
Bayliss, C. -, Burgess, L. & S. (through Rankin & Natham) Burgess, S. Campbell, J.A. Chaplin, L. Crawford, D. Cressy, R.B. Dart, J., Dooley, I. Dowling, A. Doyle, M. & I. Ebrill, J. Gallagher, R. Gillieatt, Mrs Gillieatt, P. & H. Goldman, P. Gruszynski, I. Hansen, V.R. Harris, B.M. Howard, A. & C. Howard, N. Hunt, F.D. Hutcherson, Mr & Mrs Jones, S. & Hull, B. Krick, J. Kuchera, R. Martin, R.A. Maxwell, C.M. & E. Motum, G. Motum, J. & G. Palmer, N.C. Perry, J.N. & D. Peterson, Mrs Petition, signed by 18 people Petition, signed by 210 parents of infants children at Raymond Terrace Public School Petition, signed by 33 people Price, I. Price, Mr & Mrs Ramsey, J. Robinson, M.L. Roberts, J.W. Sciater, J. & R. Stevenson, M. Stoop, W.E. Sutton, N.G. Timony, D. Tipping, B.R. & M.J. Towns, D. Tucker, A. Wade, A. (M.P. Newcastle) 39
Walter, C. Westernhagen, C.J. Westernhagen, R. Woolley, W.N. Wykis, B. & C.
Submissions by Community Organisations
Quality of Life Action Group: including a petition signed by 4,543 people. Bush Fire Brigade Concerned Citizens Group Medowie Branch of the ALP Medowie Progress Association Medowie Public School Medowie/Swan Bay Quality of Life Action Group Muiwee Public School, Parents & Citizens Newcastle District Fisherm an's Co-operative Ltd Newcastle Ecology Centre Newcastle Flora and Fauna Protection Society Port Stephens Conservation Society Society of Friends of the Lower Hunter Swan Bay Progress Association The Australian Oyster Farmers & Producers Association The National Trust of Australia (NSW) The Quality of Life Action Committee for the Swan Bay Progress World Wildlife Fund - Australia. 40
APPENDIX 2 Submission by Port Stephens Shire Council
The Director, Department of Environment and Planning, P.O. Box 3927, SYDNEY 2001
P 9/1/7/2001 Dear Sir, Environmental Impact Assessment Tomago Aluminium Smelter's Proposed Solid Waste Disposal Site at Wallaroo I refer to your letter in which you seek any advice or comments Council may wish to make about the above proposal and wish to advise that Council, at its meeting on the 14 February, 1984, resolved that your Department be advised that Council is concerned about the long term effects of the proposal on Port Stephens Waterways as it is one of the largest oyster producing areas in New South Wales and any leaching of cyanides or fluorides would not be acceptable to the Council.
Council also requests that the Commission of Inquiry gives consideration to the following six matters: Tomago claims a leach level from the excavation of less than im. per year. Can this be sustantiated by the D.E.P. Enquiry? What sort of guarantee can we get that the dump won't pollute either Newcastle's water supply, i.e. Grahamstown Dam, or reach Port Stephens and affect the oyster industry, tourist industry or residents life style?
If no guarantee can be given, what advice, on compensation arrangements would you give us in the case of a leach?
If a guarantee cannot be given, is the site worth the risk, given the problems Lake Macquarie is facing as a waste disposal dump? Would they care to comment on the statement by the House of Representatives Standing Committee on Environment and Conservation in its investigations into hazardous chemicals.
The statement is - "Many state governments lack demonstrated technical expertise in waste management with the problem being worse where local government, with even fewer resources, is expected to shoulder the responsibility. .
i.e. What is the best Body to monitor the site in perpetuity - local government or some other Body? 41
6. What other safe options for disposal are there, no matter what the cost to the Company?
Yours faithfully,
J.W. Walsh, SHIRE GLERK. 42
APPENDIX 3 Comment by State Pollution Control Commission
The Secretary, Department of Environment and Planning, 175 Liverpool Street, SYDNEY 2000 Attention: Mr. J. Shields 706991 AD M:JL Dear Sir, Environmental Impact Assessment. Tomago Aluminium Smelter's Proposed Solid Waste Disposal Site at Wallaroo I refer to your letter of 19 September, 1984, in which you requested an assessment of the document from the Tomago Aluminium Company Pty, Ltd. dated 18 September, 1984. We would like to provide the following comments.
The details given for fluoride in the report include a computational error in the original fluoride adsorption studies. This error has been confirmed by the consultant who prepared the report. Notwithstanding this error, and the resultant decrease in the safety factors mentioned in the Tomago report (p. 19), alternative calculations of our own indicate that the risk remains minimal. The movement of cyanide could not be analysed in the same way because of lack of equivalent data on cyanide adsorption or destruction. The analysis was based on the assumption that certain amounts of cyanide were released to the environment. The resultant concentrations were assessed to be sufficiently low to prevent significant impact. When account is taken of the destruction of cyanide which occurs in an aquatic environment, the risk of any impact is further reduced. These worst case scenarios for cyanide are extreme and hence unlikely to occur. They indicate that the levels of cyanide in the proposed landfill do not pose any threat to the quality of potable water in Grahamstown Reservoir, even should one of these scenarios eventuate.
Treatment of J.&.&hate There is a possiblity that geotechnical assessments and forecasts will be inaccurate. Notwithstanding that that geotechnical assessment of the Wallaroo site could be in error, we believe that any doubts or fears are satisfactorily allayed and resolved by the proposal to install sumps in the pits and monitor for the presence of any leachate. If leachate is found it can be removed and treated. This is an effective and practical means of averting any possible migration of leachate from the site, although in our view the probability of this is negligible. The monitoring sumps will of course require monitoring well into the future, although if after a number of years no leachate is detected, the frequency of monitoring could be reduced. The responsibility needs to be assured, well into the future, for the treatment of any leachate that may occur.
We are aware of processes being used to treat leachate generated by above ground waste dumps at other smelters. Free cyanides are broken down using either hypochiorite, chlorine gas or electrolysis. Soluble fluorides and complexed cyanides are precipitated using an aluminium sulphate solution, the precipitate being returned to the waste dump and the supernatant discharged along with site stormwater. If calcium were used instead of aluminium to precipitate the fluoride, the resultant precipitate would include the highly insoluble calcium fluoride which can be regarded as a non-hazardous waste for land fill disposal purposes. The supernatant would also be of a satisfactorily low fluoride level.
The data for the adsorption of fluoride by clays have been found to be in error. For instance, the adsorptive capacities in Table 1 (p. 18) should be reduced by a factor of 103. The consultant advised that this also affects the calculated retardation times (e.g. in Table 6, p. 19a). We also understand that in the adsorptive studies no fluoride could be detected in the clay sample after fluoride had been lost from the solution into which the clay was placed. At this stage any fluoride adsorptive values (whether corrected or not) should be viewed with caution. Notwithstanding the above difficulties, we consider that the extent, depth, and impermeability of the clay deposit provides a satisfactory impediment to the migration of any significant quantities of toxic leachates prior to their detection and removal from pits. With respect to possible interactions of leachate components with clays we firstly note that clays (including kaolin, a major component at Wallaroo) are relatively unreactive, and can only be chemically modified or destroyed with severe chemical conditions. Such conditions would not prevail in the current proposal. The physical and colloidal properties are, however, readily altered by the presence of other components such as those likely to occur, namely aluminium, iron, calcium, sulphur and sodium. While we agree with the proponent's comments that sodium ions would disperse the clays and decrease permeability, we note in addition, that aluminium ions (and iron and calcium ions also) would coagulate the clay and increase its permeability. However, because of the likely predominanting effect of aluminium ions, a trend to coagulation of the clay and higher permeabilities is 44 indicated. Therefore some increase in the permeability of the clay is possible particularly with extended exposure (some years) to leachate. Assuming that any leachate formed is regularly removed, we do not consider it likely that there would be any significant increase in permeability.
In summary our view is similar to that of the proponent. We consider that none of the components of the leachate present in significant quantities would be expected to have significant adverse effects on the sealing or adsorption charactertistics of the clay.
Yours faithfully,
A.D. MITCHELL £Qr Se retary Dated 16.10.84 LOCALITY PLAN SCALE 5 0 5 4 km KEY y y w Land owned by Tomago
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