Infrastructure and equipment requirements (design and construction)
The Applicant will be required to design and construct the new evaporation pond, deep litter shelters and the conventional loading shed in accordance with the requirements shown in Table 21.Table 21: Infrastructure and equipment requirements.
Infrastructure / equipment
Requirements
Evaporation pond (a) The evaporation pond must be designed and constructed to the dimensions and specifications in specified drawings.
(b) The evaporation pond must have embankments designed and constructed to prevent erosion as a result of storm water runoff including (i) appropriate embankment construction material as well as sufficient
compaction of soil; and
(ii) external batter slopes of approximately 18 degrees to maintain embankment stability
(c) The evaporation pond must be constructed with a single layer of HDPE liner with no detectable leakage that must meet the following specifications;
(i) be a minimum of 1.5 mm thickness;
(ii) have permeability less than 1 x 10-9 m/s;
(iii) be durable to maintain permeability for the working life of the ponds;
(iv) have specific gravity of 0.94 or more (ASTM method D1505) (v) have melt index of 0.05g to 0.30g in 10 minutes (ASTM method
D1238, condition E190/2016)
(vi) have carbon black content of 2-3% (ASTM method D1603) (vii) have minimum tensile strength at yield of 16 kN/m; and
(viii) have minimum tensile strength at break of 30k N/m (ASTM method D6693, type IV2)
(ix) Minimum elongation at yield of 10%, and break 300% (ASTM method D6633)
(d) The HDPE liner must be installed on a clean levelled, compacted ground soil bed that is free from plant root, sharp materials and reactive, soluble and organic matter.
(e) The evaporation pond must be designed and constructed to be fit for purpose for receiving all effluent from the maximum number of pigs on site, and of suitable capacity allowing for:
(i) Subject to (ii), a minimum operational top of embankment freeboard of 500 mm; and
(ii) Containment of a 1 in 10 ARI rainfall event of 72-hour duration without overtopping.
(f) The installation of the HDPE liner must be supervised by a competent and experienced geo-technical professional.
Six dry litter shelters (a) The domed cover of the shelters are to be constructed from a water-proof and non-reflective PVC plastic.
Infrastructure / equipment
Requirements
(b) The shelters must have half wall height concrete and brick walls on two sides.
(c) The shelters must have a concrete floor with a 1.5m concrete apron outside each end of the shelter.
(d) All shelters are to include a raised feeding area which is 3m in depth and 100mm above the floor of the shelterswhere self-feeders are included in the feeding area.
One conventional flushing loading shed
(a) The shed is to be enclosed with air ventilation from a ridge cap roof and wall gaps within the upper walls.
(b) The shed must comprise of concrete and partially slatted floors.
(c) The shed must have a concrete flushing channel underneath that is directed to a suitable sized existing soak well and pumped to the hardstand area for treatment.
(a) The flooring and drainage system must prevent the discharge of effluent to the environment.
Grounds: The infrastructure design and construction requirements address the risk of loss of containment and seepage impacts. The controls are largely based on Applicant proposed controls.
Groundwater monitoring bores (design and construction)
The works approval will require the installation of four new groundwater monitoring bores as shown in Figure 5 and described as follows:
MB5 Superficial bore screened interval from 3-6mbgl opposite Facultative Pond 1 along the western boundary.
MB6 Seasonal groundwater bore / piezometer, 1 to 1.5m screen interval from claypan Located next to MB5, opposite Facultative Pond 1 along the western boundary.
MB7 Superficial bore screened interval from 3-6mbgl directly behind on the western edge of the 6 new piggery shelters.
MB8 Seasonal groundwater bore / piezometer, 1 to 1.5m screen interval from claypan Located next to MB7, directly behind on the western edge of the 6 new piggery shelters.
Grounds: Monitor for potential impacts to groundwater from the piggery infrastructure. Based on hydrogeological information, bores are to be located in the superficial aquifer. Once installed, monitoring of the bores will be required through a licence amendment.
Table 22: Summary of conditions to be applied
Condition Ref Grounds
Infrastructure and equipment Condition 1, 2, 3 and 4
Risk-based condition to ensure appropriate linkage between approved works and the EP Act and contain appropriate controls.
Emissions Condition, 5
This condition is valid, risk-based and consistent with the EP Act.
Groundwater Monitoring Condition 6 and 7
Environmental compliance is a valid, risk-based condition to ensure appropriate linkage between the licence and the EP Act.
Record Keeping and Reporting 8, 9 and 10.
These conditions are valid and are necessary administration and reporting requirements to ensure compliance.
DWER notes that it may review the appropriateness and adequacy of controls at any time and that, following a review, DWER may initiate amendments to the works approvals under the EP Act.
Post-construction licence controls
The Applicant will need to apply for a licence amendment prior to completing construction for amendment of the licence to reflect new infrastructure. On the basis of this assessment, the following types of controls will be included on the licence:
Inclusion of new infrastructure on the licence;
Maintaining evaporation pond freeboard;
Deep litter shelter solid waste management;
Solid waste application to land requirements including a limit of 55 m3 of waste applied to land. Where the Applicant supplies additional information to support risk based assessment of potential receptor impacts, the Delegated Officer will further review an alternative rate of solids applied to land.
Inclusion of the four new groundwater bores in the quarterly groundwater monitoring program, which are intended to supersede requirements to sample the existing bores (MB2-MB4) due to the factors discussed in section 5.1.1.
Removal of existing irrigation requirements as irrigation will cease with the operation of the new evaporation pond.
Dependent on the timing of construction completion and a licence amendment application from the Applicant, the Department may initiate an amendment to phase out conditions relating to the burial of pig mortalities within the premises.
In the absence of implementing an alternative suitable method of mortality disposal, it is intended that the Existing Licence conditions will be limited to offsite disposal of mortalities. The Applicant may seek to amend the works approval or submit a separate application to DWER where additional infrastructure is proposed (e.g. pig mortality composting infrastructure).
The following points summarise the reasoning for this:
Groundwater at the Premises is shallow, with standing water level data in monitoring bores indicating groundwater at approximately 1 to 1.5 m bgl, which provides a direct pathway to groundwater. DWER Officers visiting the site on 30 September 2018 observed surface expression or inundation of areas of the Premises from recent winter rainfall.
QDAF 2018 guidance indicates the burial of pig mortalities is problematic in shallow groundwater area and where burial pits cannot be kept dry.
NEGIP advises that:
o while burial is a common mortality disposal method, it should only be used where rendering or composting are not feasible, and it is not the preferred method. NEGIP notes that nutrients and bacteria can leach into and contaminated groundwater, particularly if this is shallow and the pits are not well sealed;
o pit bases must be at least 2 m above the water table at all times;
o pits should be situated on low permeability soils and/or low risk sites
The Applicant will be increasing the SPU design capacity and therefore there rate of pig mortalities requiring disposal is likely to marginally increase.
The Applicant did not propose any changes to management and disposal of pig mortalities in its works approval application or any infrastructure related to alternative mortality
disposal.
Applicant’s comments
The Applicant was provided with a draft Decision Report and works approval on 2 April 2019 for
comment. The Applicant provided written feedback on 1 May 2019 and 27 May 2019 advising there were inconsistencies in the Decision Report with what the Applicant proposed to construct and these inconsistencies impacted the assessment outcomes and the determined controls.
The Delegated Officer reviewed the assessment taking into consideration the Applicant’s comments and a DWER Officer undertook a site visit on 10 October 2019. A revised draft Decision Report and draft works approval was provided to the Applicant on 29 November 2019 and feedback was provided on 19 December 2019. The Applicant advised that Table 6 of the works approval should include the new conventional loading shed, and that inconsistencies of terminology referring to shelters and sheds are to be addressed, noting that HDPE domed covered housing is referred to as shelters and fixed roof constructions referred to as sheds.
These errors and inconsistencies have now been corrected. The Applicant also requested clarification that the new proposed groundwater monitoring bores will supersede requirements to sample existing bores. Potential issues with existing bores MB2-MB4 were discussed in section 5.1.1 and it is intended the new bores supersede requirements to monitor existing bores.
Additional clarification has been added to section 10.1.3.
Conclusion
This assessment of the risks of activities on the Premises has been undertaken with due consideration of a number of factors, including the documents and policies specified in this Decision Report (summarised in Appendix 1).
This assessment was also informed by a site inspection by DWER officers on 30 September 2018 and 10 October 2019.
Chris Malley
A/Manager, Process Industries
An officer delegated by the CEO under section 20 of the Environmental Protection Act 1986