En EnvStand16 Landfill-Design & Operation

Environmental Standards

Landfill – Design and Operation

KSA Presidency of Meteorology and Environment PME Reference

Kingdom of Saudi Arabia Page 1 of 27

Part I – Preliminary

1) Definitions

‘authorisation process’ refers to the determination of all applications for the development of a new landfill by the Competent Agency up to the point where permission is granted for development. ‘bunds’ are systems which contain waste in an embankment or secondary container to prevent the waste from travelling or escaping. ‘Competent Agency’ where referenced, refers to the Presidency of Meteorology and Environment or its designated representative. ‘construction quality assurance plan’ (CQA) refers to the construction quality control and quality assurance documentation to be provided outlining the successful construction of the landfill and providing evidence that all design performance specifications have been met. Construction quality control and assessment must be performed by a qualified contractor that is not contracted to, or working for the construction company, but rather, this work is done independently of the construction contract. ‘disposal’ means the discharge, deposit, injection, dumping, spilling, leaking, or placing of any waste into or on any land or water so that such waste or any constituent thereof may enter the environment or be emitted into the air or discharged into any waters, including ground waters. ‘generator’ is a commercial or industrial organisation which produces or stores trackable waste and arranges for this waste to be sent for storage, recycling, treatment or disposal at another location via an authorised transporter. ‘GER’ refers to the Kingdom of Saudi Arabia’s General Environmental Regulations 2001. ‘hazardous waste’ is a waste with properties that make it dangerous or capable of having a harmful effect on human health and the environment. ‘homogeneous’ refers to materials which are similar in terms of their physical content. ‘inert waste’ refers to waste which is chemically, physically and biologically unreactive. kPa’ refers to one kilopascal, defined as the pressure exerted by a 10-g mass resting on a 1-cm2 area. 101.3 kPa = 1 atm. 1,000 pascals = 1 kilopascal.

‘KSA’ refers to the Kingdom of Saudi Arabia. ‘landfill’ is any facility, other than a ground treatment facility or a storage pool, where wastes are disposed of in an environmentally safe manner either by placing them on the ground or burying them underground. ‘landfill designer’ refers to the entity involved in providing the documentation to support the development of a landfill. ‘landfill operator’ refers to the entity involved in the development of the landfill site. ‘major landfill’ refers to a landfill of significant size which has been developed to provide disposal capacity for a large local population (>500,000 people). ‘non-cohesive’ refers to materials which are granular in nature and which do not bind together easily, such as sand and gravel.

‘parameter’ shall refer to a chemical, physical or biological measurement factor as listed within this and other associated standards. ‘permanent road’ is a road which is stabilized and suitable for use as an access way to a landfill. The road may be earth stabilized, or may be constructed of asphalt, concrete, geofabric/geotextile, or other suitable structural material. ‘PME’ refers to the Presidency of Meteorology and Environment who are designated as the responsible authority for the protection of the environment and the development of environmental protection standards in the Kingdom of Saudi Arabia. ‘recycling’ is the separation and collection of wastes materials for the subsequent transformation or remanufacture into usable or marketable products or materials. ‘risk assessment’ is the process of identifying and quantifying a risk and assessing the significance of that risk in relation to other risks. ‘storage’ means all operations intended to keep or contain wastes and other hazardous, toxic or radioactive substances for the purpose of treatment, transportation or disposal. ‘tanks’ are stationary devices, as opposed to portable containers, used to store or treat waste. Tanks can be open topped or completely enclosed, and may be constructed of materials including steel, plastic, fibreglass, and concrete.

Kingdom of Saudi Arabia National Environmental Standard

Landfill – Design and Operation



‘transporter’ means a person engaged in the off-site transportation of waste by air, rail, highway or water and is anyone who transports the trackable waste from its place of production or storage to another location. ‘treatment’ is any means or technique of altering the physical, chemical or biological properties of wastes used to neutralize such wastes; utilize substances or energy contained therein or released by them; and transform the hazardous wastes into wastes that are non-hazardous, less hazardous or safer when transported, stored, disposed of, prepared for storage, or reduced in volume. ‘TSD facility’ refers to a treatment, storage and/or a disposal facility. ‘unreactive’ refers to the properties of a waste where there is no chemical, physical or biological reaction likely to occur through the landfilling process. ‘v/v’ refers to the volume to volume ratio between two gaseous materials. ‘WAC’ refers to Waste Acceptance Criteria. ‘waste handler’ is a generator, transporter and receiver of waste who has waste responsibilities. ‘waste receiver’ is any person operating a facility to whom waste is transported for recycling, storage, treatment or disposal. ‘waste tracking’ is the recording of information from the waste generator about the quantity and type of waste produced; recording information about who transported the waste and when; recording information from the waste receiver about the quantity and type of waste received; and matching information about the waste from both the generator and the receiver. ‘working plan’ is the operational plan developed prior to the acceptance of waste which sets out the operational methods to be used on site and demonstrates how environmental and human health impacts will be managed and controlled.

2) Citation

a) This document may be cited as the National the Landfill Design and Operations Standard for KSA. This standard revises the current General Standards for the Environment (specifically document number 1409-01 and 1423-01) issued by the Presidency of Meteorology and Environment (PME).

3) Timescales for implementation

. a) The effective date of this standard is 01/05/1433H

corresponds to 24/03/2012G.

4) Purpose a) The objective of this standard is to establish the framework which facilitates the:

i) design of new solid waste landfill facilities

which accept waste of all types from across the KSA whether a material or substance is inert, non-hazardous or a hazardous waste and

ii) operation of a solid waste landfill to

ensure that the sites are managed in a manner which will have least possible impact upon the neighbouring environment or human health;

and accordingly the Landfill Design and Operations Standard and the codes and chapter headings shall be recognised and used for those purposes. b) The Standard guides those developing and operating solid waste landfill sites to:

i) Understand the best practice

requirements with respect to landfill design and operation.

ii) Develop new landfill sites with due regard

to international best practice.

iii) Understand the necessary site development requirements for landfill sites dealing with different waste types.

iv) Provide for future site closure and after

care requirements on completion of the landfill operations.

c) The Standard is intended for use as a default position for landfill design, operation, site closure and remediation. The Standard applies to all new landfills pre-development. However, existing landfill operators must, as far as practicable, implement the relevant best practice measures contained within this Standard.

5) Scope

a) This Standard sets out the design parameters and operational requirements through to site closure and aftercare for solid waste landfill in the Kingdom of Saudi Arabia. b) This Standard does not apply to the:

(i) management of radioactive waste;

(ii) management of liquid wastes;

(iii) spreading of sludges, including sewage

sludges and sludges from dredging operations for the purposes of fertilisation or land improvement; or

(iv) remediation of existing landfill sites.



6) Exemptions

a) Specific exemptions may be specified within this standard at any point where relevant to the Article that they are common to.

7) Powers of Authority

a) Within the scope of these standards the Competent Agency may:

i) prescribe specific requirements at any time as to other characteristics of landfill design;

ii) authorise such relaxations or departures

from, the landfill design standard and make any such authorisation subject to the prescribed conditions, and to modify or revoke any such authorisation or condition; and

iii) authorise a local Concerned Agency to

exercise any power conferred by these regulations by paragraphs i) - ii) above.

b) The Competent Agency may, for the purposes of this Standard, appoint persons to act on their behalf as technical assessors and monitors in relation to the powers and duties conferred on him by this standard and/or its subsequent amendments. c) In addition to the responsibilities conferred by other sections contained within this standard, it shall be the duty of a relevant party;

i) to give the Competent Agency all such assistance; and

ii) to provide the Competent Agency with all such information, as that may reasonably be required for the purpose of carrying out an investigation

d) The Competent Agency or appointed individual for the purpose of land fill design regulation may:

i) Enter any premises for the purpose of carrying out any investigation. ii) carry out such inspections, measurements and tests on premises entered, articles or records found on any such premises, and take away such samples of waste or articles, as may be considered appropriate for the purpose of enabling such investigation; or iii) at any reasonable time require any relevant party to supply him with copies of, or of extracts from, any records kept for the purpose of demonstrating compliance with the landfill design standards.

e) This standard enables the issue of regulations and technical memoranda which are enforceable by the Competent Agency who hold delegated authority under the General Environmental Regulations.

8 Enforcement Procedures

a) Failure to comply with the requirements of these standards may lead to prosecution by the Competent Agency and those convicted of such failure may be subject to fines or periods of imprisonment as laid out in the General Environmental Regulations. b) It is anticipated that the requirements of this standard will be enforced nationally with inspections taking place to verify their implementation at a regional and local level. .

9) Penalty fines a) Maximum fines that may be imposed for

contravening the applicable standard, breach of permit and failure to comply with an abatement notice are set out in the General Environmental Regulation

10) Appeals

a) A right of appeal exists for any organisation or individual who is required to take action as a consequence of the implementation of the revised standard. b) The right of appeal against conviction or sentence is available through the appropriate judicial system as set out in the General Environmental Regulations.

c) All appeals should be fully supported with a documented case containing as a minimum, the information required under the appeals process of the General Environmental Regulations.

11) Periodic review

a) There may be some requirement at a future date to adjust the standards included to recognise specific local conditions. b) As a minimum, the Competent Agency shall undertake a periodic review of this standard every 5 years. c) Where new information suggests that adjustments are required to this standard, all changes will be subject to the appropriate consultation and will be notified to facilities by the Competent Agency. Appropriate implementation time will be allowed.



Article II – Landfill Classification

a) The classification of landfills is based upon the type of wastes which they are permitted to accept through their gates. There are more stringent requirements placed upon wastes which have the potential to cause harm to human health or the environment.

1) Landfill Types

a) Three landfill types have been identified (see the Waste Acceptance Criteria Standard and the Training and Assessment of Technical Competence of Operators Standard) which require different levels of detailed design depending upon their potential to impact on human health or the wider environment. These are:

i) Class 1 Landfills - Hazardous Landfills

which may only accept Hazardous wastes which satisfy site specific acceptance criteria;

ii) Class 2 Landfills - Non-Hazardous

Landfills which may accept any wastes which are considered to be non-Hazardous including municipal waste, commercial waste, stable non-reactive hazardous wastes, inert wastes and others as demonstrated through appropriate investigation and risk assessment; and

iii) Class 3 Landfills - Inert Landfills which

may only accept waste which is known to be inert (that is, physically, chemically or biologically unreactive).

Article III – General Provisions

a) The following outlines the requirements with respect to the design of all landfills including specific requirements for cell design, landfill liners, leachate management, landfill gas management, construction quality assurance (CQA) of the design parameters, litter and pest/vermin control, closure and aftercare.

b) These provisions are generic for all landfills. Where risk assessments and investigations identify that a lesser standard is required for example, for inert waste landfills, then this justification will be taken into account during the Authorisation Process. The minimum information required for authorisation purposes is outlined in Appendix 1.

1) Environmental Assessment

a) An Environmental Assessment will be required prior to the development of a landfill site for both Class 1 and Class 2 landfills. This will be necessary to gain a thorough understanding of the environment where the landfill is to be sited in order to design the landfill to minimise impacts on the environment.

b) As a minimum requirement the Environmental Assessment should include the items outlined in Appendix 2.

2) Site Location

a) Careful consideration must be given to the location of sensitive receptors down wind/ down gradient of any newly proposed landfill to ensure adequate protection of the environment and human health. The actual b) When locating a landfill site consideration must be given to the:

i) distance from the site boundary to

sensitive receptors such as recreation areas, residential properties and associated community establishments (schools, hospitals, etc) (>250 metres), coastal water resources (>100 metres) and agricultural areas (>100 metres), pipelines and highways (>30 metres), aviation runways (3.3 km);

ii) presence of groundwater, surface water,

coastal water or nature conservation zones;

iii) geological and hydrogeological conditions

underlying the site; and

iv) other undetermined local factors which could be impacted by a proposed landfill site and which will be identified at the local level during the Environmental Assessment.

3) Site Specific Design Considerations

a) All new landfill sites must be designed with the desire for the least possible local impact and where possible they must blend in with the local surroundings. b) Site factors which affect landfill design include (but are not limited to):

i) topography;

ii) size and shape of the property area;

iii) subsurface geological and

hydrogeological conditions;

iv) surrounding land use;

v) local availability of cover materials;

vi) local ecological aspects;

vii) seismic considerations; and

viii) access and ease of transport to the site.



c) A detailed pre-construction plan must be provided to the Competent Agency a minimum of six months prior to construction along with the submittal of the Environmental Assessment. Details of the requirements for this plan are provided in Appendix 1. d) A new landfill site must not be established by any person, nor an increase in the volume of an existing landfill be exercised, unless a written report has been prepared in accordance with Appendix 1.

4) Site Layout

a) Landfills and associated facilities must be designed to:

i) Minimise potential environmental impacts;

ii) minimise health and safety risks for landfill

operators and the public;

iii) encourage waste recovery; and

iv) use onsite resources efficiently.

b) To assist in meeting these requirements a detailed site layout plan must be provided to the Competent Agency as part of the Working Plan for the site prior to the development of a landfill to provide evidence that key concerns have been considered and addressed prior to the development works (both for public landfill sites and private landfill sites owned and operated by industry).

c) On landfills where there is general access to the public for the drop off of wastes a TSD Facility with recycling and drop-off areas must be provided to reduce the need for the public to unload their vehicles at the tipping area to minimise safety risks. d) On landfills serving a large local population a gatehouse is to be provided at the entrance to the site, or at a suitable point which cannot be by-passed by waste transporters when travelling to the landfill, to provide for the validation of wastes to confirm their suitability for receipt at the site.

e) A number of facilities should be provided at the gatehouse to provide the attendant with the best practicable opportunity to confirm the acceptability of incoming wastes including:

i) A viewing platform which allows a view of

the contents of incoming lorries; and

ii) elevated mirrors or CCTV cameras which can be used to scrutinise incoming loads.

f) A weighbridge must be installed at landfill sites serving a population greater than 25,000 to facilitate accurate record keeping of wastes entering and leaving the site for all necessary administrative and regulatory purposes.

g) The weighbridge should be calibrated in accordance with manufacturer’s recommendations at least annually to confirm the accuracy of records. A logbook of weighbridge inspections and certifications must be maintained by the landfill operator.

5) Risk Assessment

a) For all classes of landfill, a risk assessment must be carried out by the landfill operator, taking account of the site engineering and leachate and gas management measures (if present), to demonstrate that the acceptance of a waste would meet the following criteria in both the short and long term (post closure);

i) there are no unacceptable emissions to

groundwater and surface water and the surrounding environment;

ii) the environmental protection systems

such as liners, leachate and gas collection and treatment systems at the site are not jeopardised;

iii) waste-stabilisation processes such as

degradation or wash out within the landfill are protected; and

iv) there is no unacceptable risk to human

health.

b) The risk assessment may make it necessary for a particular site to have additional limits to the full WAC due to;

i) the environmental context of the landfill

may be more sensitive than that used for modelling the WAC;

ii) the lining and leachate collection systems

perform differently from those used for modelling the full WAC; and

the waste may have attributes not covered by the full WAC.

Article IV – Site Infrastructure Requirements

1) Roads

a) Local infrastructure must be able to sustain the operation of a landfill. Landfilling requires the transportation of waste. The capacity of the road network to cope safely with any increased traffic load and with a minimum of disturbance to the local community must be examined as part of site pre-development requirements. b) The preferred transportation route to the landfill from the source of the waste or other TSD Facility must minimise the transport of waste through residential and other sensitive areas. This consideration may influence the placement of the entrance to the landfill.



c) Access to the site will form a mixture of permanent roads from the main highway through to temporary roads near the face of the landfill. Consideration must be given to the landfill site’s requirements for permanent roads within the site boundary, especially on larger sites.

d) Where incoming vehicle movements exceed 100 movements per day a permanent road must be provided within the site. Permanent roads may not be required where there are lower vehicle volume movements and conditions are dry and soils well graded and compacted. e) Permanent roads must be designed with due regard to the estimated volume of traffic. Where possible, two lane traffic (minimum total road width of 7.5 metres) should be provided to allow efficient entrance and exit from the site.

f) Road gradients must be designed for the safe operation of traffic on site. Gradients must not exceed 7%. g) Temporary roads will need to be constructed on site as the working face changes. Temporary roads must be constructed on the landfill (where necessary) via compaction of the existing soils. Where necessary, temporary roads should be topped with materials to improve traction, such as gravel, crushed stone or crushed inert wastes from construction and demolition activities. Serviceability can be improved through the addition of lime, cement, or asphalt binders where required.

2) Surface Water Drainage

a) The management of surface water on landfills is a key consideration as water provides for major impacts upon the operations of a landfill through:

i) interference with site operations through

reduction in traction across the site; and ii) contributing to leachate generation.

b) Surface water must be adequately controlled through the construction of a network of interception ditches across the site between the operating areas and the surrounding areas of the site. Surface waters which come into contact with waste on the site must be diverted to a surface water collection area (such as a lined storage pool separated from all landfill cells) where further treatment or evaporation can be carried out as required. Surface waters which do not come into contact with the waste mass, or are not subject to contamination through leachate should be diverted without further controls.

c) The design of the drainage system must be taken into account during the pre-development stage to assist in optimising the utilisation of surface water and minimising the impacts of uncontrolled water ingress.

d) Accumulation of water within the working area must be controlled to provide for optimum landfilling conditions. The utilisation of water in arid conditions can assist in the final stabilisation of the landfill, but must be controlled. Controlling the size of the operating areas and providing for daily cover of the open face assist in controlling surface water ingress and uncontrolled leachate production.

e) Additionally, temporary covered working areas should be graded to provide for surface water runoff to the network of drainage ditches. Long term control is provided through the temporary or permanent capping of filled areas on completion of the final design level.

f) Storage pools and other drainage measures must be designed to contain and control rainfall runoff for a 1-in-20 year storm event for a Hazardous or Non-Hazardous landfill or a 1-in-10 year storm event for a solid inert landfill. g) Storm events up to 1-in-100 year recurrence intervals must also be considered at the design stage to ensure that they do not result in any catastrophic failures such as flooding of the landfill or failure of dams or leachate storage ponds where applicable.

3) Utilities and Facilities

a) Electricity, water, sanitation and communications facilities must be provided at all landfill facilities to ensure the health and safety of on-site personnel, and to enable control of operations on site (such as dust control, vehicle washing and fire fighting). b) As a minimum temporary structures must be located on site providing accommodation to on site personnel. Such structures must be designed to provide:

i) office space for general site management

duties and records storage;

ii) sanitation facilities for site staff and visitors.

iii) storage space for site equipment and for

maintenance purposes; and

iv) first Aid area, fully stocked for minor accidents.

c) The location of temporary or permanent site structures must take account of landfill settlement and landfill gas production and potential gas migration. All structures must be located in a suitable area of the site to allow control of day to day activities whilst also taking account of health and safety aspects. d) Where landfill gas is known or likely to be generated, gas control measures must be included within the design of structures to ensure that build up of gas does not occur within the building as gas can



move out of the site where there are fissures which allow migration.

4) Fencing

a) A fence (or elevated earth berm in remote areas) must be constructed around the perimeter of the landfill to:

i) reduce onsite trespass, especially from

vulnerable members of the population, and animals;

ii) provide a screen for the landfill;

iii) delineate the property lines; and

iv) provide a control for litter blow.

b) Fences must be a minimum of 2 metres tall around the entire perimeter of the site. c) However, higher fences may be required down wind of the site to limit litter blow off site, especially where there are potentially sensitive land uses down wind of the site. Alternatively, portable litter fences over 3 metres in height which are placed near to and down wind of the open landfill face may suffice.

5) Vehicle/Wheel Wash Areas

a) On large landfill sites (serving major population centres of >500,000 people and in close proximity to local communities) which accept municipal or hazardous waste, an area of the site must be set aside to allow for the washing of onsite vehicles and lorries which bring waste into the site. Such an area will require:

i) a reliable water supply; and

ii) an area of hardstanding (concrete/tarmac)

which leads wash water runoff to the surface water collection system.

b) Wheel washing facilities must be placed in line with the paved road leading to the exit from the site to remove mud from vehicle tyres before exit back onto the main highway. Wash water and sediments from the wheel washing trough must be disposed of through the on-site surface water drainage system.

6) Unacceptable Load Quarantine Area

a) An area of the site must be made available to allow for the temporary segregation of suspect, burning or unacceptable waste loads which enter the site. This area should be located away from the main areas frequented by personnel. Water must be available in case of burning waste loads. b) This area must be clearly marked with reference to its required purpose to ensure that there is no inadvertent mixing of waste materials.

c) A paved surface area of 10 metres by 10 metres minimum must be provided, with its own linked drainage collection system. All drainage from this part of the site must be collected and held in segregation until laboratory testing proves that it is suitable for discharge into the onsite surface drainage system. Where unsuitable, the wash water must be tankered off for offsite treatment at a suitable water treatment facility.

Article V – Landfill Design Standards

1) Cell Design

a) All landfills will be developed as a series of cells. A cell is formed by the spreading and compaction of incoming wastes in layers within a confined area.

b) Individual daily cells must be placed sequentially and compacted as the landfill develops. A series of adjoining cells developed over the landfill at the same height constitutes a ‘lift’ (normally between 2 and 4 metres depth).

c) At the end of each working day the compacted waste within a cell must be covered by a thin continuous layer of locally recovered cover material of approximately 150 mm (including the working face).

d) All cells must be designed to accommodate the likely volumes of waste. Dimensions of a cell are affected by:

i) the quantity of waste accepted daily;

ii) daily cover requirements;

iii) slope stability; and

iv) degree of compaction.

e) Cell width must also be taken into consideration as this important parameter will impact upon site operations. Table 1 illustrates suggested minimum widths in line with daily imports of waste material.

Table 1: Suggested Minimum Cell Widths as a Function of Daily Waste Quantities

Quantity of Waste (tonnes per Day)

Minimum Cell Width (metres)

20 to 50 25 to 130 130 to 250 250 to 500

8 10 12 15

f) The maximum recommended slope for a cell is 1 vertical to 4 horizontal, although slopes of lesser steepness are preferred as maximum compaction is achieved when the angle of the working face is close to horizontal.



g) Where the outside slopes of a cell constitute the final landform they must be at a slope of 1 vertical to 3 horizontal or less depending upon slope stability and potential erosion impacts. In seismically active areas maximum final slopes must be 1 in 5.

2) Landfill Liners

a) The primary functions of a landfill liner system are to:

i) protect groundwater from impacts of

leachate through reducing the vertical seepage of leachate;

ii) attenuate contaminants in leachate

seeping through the liner to the point where the leachate that makes contact with the aquifer beneath the landfill has minimal detrimental impact on groundwater; and

iii) retard lateral movement of landfill gas

from the landfill and to limit the infiltration of groundwater.

b) The landfill designer must ensure that the liner system is geotechnically stable between components and as a total system. A risk assessment will be required to demonstrate the performance of any proposed landfill liner system. The risk assessment must consider:

i) the operational and post-closure phases;

ii) failure and degradation of other controls,

such as the clay liner, the leachate management system and operational/ management controls including groundwater pumping;

iii) likely variation of leachate concentration

with time;

iv) stability and settlement; and

v) the role of the barrier in controlling landfill gas.

c) The results of this risk assessment will feed into the final design parameters of any landfill liner required on a site specific basis as this will be dependant upon the:

i) volume of precipitation and potential

infiltration.

ii) moisture content of the waste entering the landfill.

iii) Volumes of leachate which will be

produced within the landfill.

iv) depth to underlying aquifers.

d) The design objective of the liner and leachate collection system is to protect the beneficial use of all groundwater, including that directly beneath the landfill. Appendix 4 provides the List I and List II substances which have the greatest impact upon ground and surface water resources as the major likely constituents of leachate. The liner must be sloped into the leachate collection pipes which in turn are sloped to the leachate collection sump.

e) Liners comprise up to five components depending upon the level of groundwater protection required:

i) sub-base;

ii) clay layer;

iii) geomembrane and protection layer.;

iv) drainage layer/leachate collection system;

and

v) geotextile.

f) To meet the performance standards of the whole liner for a Non-Hazardous or Hazardous waste landfill, the whole liner system (which will be made up of all or some of the above components depending upon site specific risk assessment) must, must, unless otherwise agreed, provide for a hydraulic conductivity of less than 1 x 10-9 m/s for hazardous sites and 1 X 10-5 m/s for nonhazardous sites. Landfills designed to operate under a greater hydraulic conductivity must prove through risk assessment that there is no additional impact on human health or the environment prior to construction, and petition to the Competent Authority for exemption. g) Sub Base: The sub base will normally constitute the underlying natural solid geology, or well consolidated drift geology. The role of the sub base is to provide a suitable base for the clay layer and to limit settlement which could cause problems for any artificial geomembrane used within the construction of the liner.

h) All plans for the construction of a sub base must be verified and approved by a suitably qualified and experienced Geotechnical engineer. To provide assurance of the quality of construction of the sub-base, construction of the sub-base must be included in any Construction Quality Assurance (CQA) plan which accompanies the landfill design documentation, verifying that it is fit for its intended purpose.

i) Clay Liner: Clay provides a suitable material for the development of a low permeability liner for Hazardous and Non-Hazardous landfill sites in areas where there is a potential risk to ground or surface waters.

j) Before clay is used to construct a liner, samples of the clay to be used must be submitted to a laboratory for determination of the soil properties for a range of compaction efforts. This will enable the development



of laboratory compaction and hydraulic conductivity curves which should be assessed to determine the suitability or otherwise of the material as a low permeability barrier.

k) Key elements of the clay layer are that it provides:

i) a barrier to the movement of

contaminants; and ii) extended cover along the entire base of

the landfill and up the sides to provide full containment (taking into account the stability of any side wall lining system).

l) All plans for the construction of a clay liner must be verified and approved by a suitably qualified and experienced Geotechnical engineer. To provide assurance of the quality of construction of the clay liner, construction of the clay liner must be included in any Construction Quality Assurance (CQA) plan which accompanies the landfill design documentation, verifying that it is fit for its intended purpose. m) Compacted powdered marl has been shown to provide a suitable liner for some non-hazardous landfills in the Kingdom without additional significant risk to underlying groundwater. Where this is to form part of the lining system (as opposed to clay) for new landfills a risk based approach will be adopted to ensure that proposed designs are suitable within the context of each and every specific landfill. Soils testing in a geotechnical or soils laboratory are required to determine if the compacted powdered marl meets the construction and design parameters for the project. n) Geomembrane: A Geomembrane consists of a prefabricated polymeric sheet. The suitability of a Geomembrane and the protection it affords is based upon:

i) the number of defects within the liner

material; ii) tears or imperfections at the join; iii) holes resulting from folds in the

Geomembrane, or sharp objects penetrating it;

iv) compatibility of the Geomembrane to the

waste types disposed of within the fill; v) ability to withstand deterioration under

ultraviolet light; and vi) grade of slopes over which it is to be laid.

o) Porous materials must not be placed between a geomembrane and a clay liner. The clay liner must be shaped to a smooth surface before installing a geomembrane to reduce the overall surface area of the clay liner and thereby reduce the potential for liner damage.

p) The landfill designer must make every reasonable endeavour to ensure that the geomembrane to be used is the most appropriate under the circumstances and that it meets the physical and mechanical requirements summarised in Appendix 3.

q) All plans for the construction of a geomembrane liner must be verified and approved by a suitably qualified and experienced Geotechnical engineer. To provide assurance of the quality of construction of the geomembrane liner, construction of the liner must be included in any Construction Quality Assurance (CQA) plan which accompanies the landfill design documentation, verifying that it is fit for its intended purpose, with due regard to paragraph l) above. Construction and installation of a liner must be certified complete by independent quality assurance quality control construction monitoring.

r) Drainage Layer/Leachate Collection System: The leachate collection system is an integral component of the overall landfill liner system. A leachate collection system typically comprises a high permeability drainage layer, perforated collection pipes, a sump where collected leachate is extracted from the landfill and geotextiles to protect any geomembrane and prevent clogging of the drainage layer. It must be designed to:

i) drain leachate such that the leachate

head above the liner is minimised;

ii) collect the estimated volume of leachate (predicted by water balance models);

iii) resist chemical attack, and physical,

chemical and biological clogging;

iv) withstand the weight of waste and the compaction equipment without crushing; and

v) provide ease of inspection and cleaning.

s) The maximum permissible leachate head on the liner (as measured at the lowest point of the liner) for a landfill situated above the water table is 0.3 metres.

t) No new landfill will be permitted on areas where there is likely to be close contact between the landfill base and the water table, except where the filling is to take place as part of a land reclamation project to expand the shoreline. Where such land reclamation works are permitted, the fill material is limited to inert materials.

u) The drainage layer is a high-porosity medium providing a preferential flow-path to the leachate collection pipes and/or sump. The hydraulic conductivity of the drainage layer must be greater than 1x10–3 m/s. The drainage layer must be placed across the entire landfill and comprise at least 0.3 metres of coarse aggregate or a geosynthetic drainage material with the equivalent performance.

v) The aggregate to be used in constructing a drainage layer must be selected to maximise



drainage of leachate in the long term. Recommended properties are:

i) 85% of the material not less than 40 mm; ii) 10% of the material not less than 20 mm; iii) uniformity coefficient less than 2; iv) fines content less than 1 per cent by

weight; and v) no limestone or other calcareous material

that would be subject to chemical attack.

w) A number of controls must be put in place to reduce the potential for short to medium term leachate collection system failure:

i) prevent clogging with silt or mud; ii) prevent micro-organisms clogging the

pipes; iii) prevent precipitation from chemical

reactions; iv) ensure pipes are not damaged during

installation or early in the filling of the landfill; and

v) prevent the pipes becoming weakened by

chemical attack (acids, solvents, oxidising agents, or corrosion) and are crushed.

x) To reduce the risk of mechanical failure of the leachate collection pipes, they must be:

i) flexible rather than rigid; ii) placed in trenches; iii) placed on evenly prepared bedding

material; and iv) protected by a traffic-control program

minimising the movement of heavy vehicles across them until sufficient waste has been placed over the drainage layer to avoid puncturing.

y) Geotextile: A geotextile filter should be placed over the drainage layer to protect it from clogging as a result of solids transport. Leachate collection pipes must not be wrapped in a filter geotextile, as they rapidly clog, rendering the collection pipes ineffective. Table 2 highlights minimum geotextile criteria for use in subsurface drainage applications. Table 2 Geotextile Criteria for Subsurface Drainage (after AASHTO M288-96)

Filter Criteria Percent Soil Passing No. 200 Sieve<15% 15 – 50% >50%

Minimum permittivity (per second)

0.5 0.2 0.1

Maximum Apparent Opening Size (AOS) (mm)

0.43 0.25 0.22

3) Liner Protection and Leak Detection

a) The Operator should select a suitable material to provide appropriate liner protection. A range of materials including mineral materials, thick geotextiles, sheets made from bonded rubber crumb may provide appropriate protection. Where mineral layers are used for liner protection, they are generally finer grained, 300 mm thick or more, overlain by a separation geotextile and the leachate collection system.

b) The Operator must ensure that the placement of the protection layer does not damage or over stress the liner. The Operator must provide erosion control, particularly on sloping areas via re-vegetation where possible.

c) The performance of the liner system must be monitored in order to verify design assumptions and inform the design of future phases. This will require installation of permanent or semi-permanent monitoring systems to verify design assumptions in the short to medium term.

d) The use of geophysical leak detection is required on all composite liners where the upper barrier is a geomembrane, to check for defects after the installation of the leachate drainage layer and prior to waste deposition.

e) A risk assessment will be required to determine the need for a leakage interception layer within the lining system. The system should be divided into sections for risk assessment purposes to assist in the location of any significant leakage, and in its possible remediation.

f) Where present, the leak interception system should be carefully monitored and the results interpreted carefully.

g) Where there is likely to be considerable leachate produced interception facilities must be constructed for the collection of leachate to provide a contingency for unanticipated seepage.

4) Landfill Gas Management

a) Landfill gas (a cocktail of methane, carbon dioxide and other trace gases) will be produced by landfills which accept biodegradable wastes. Landfill gas (at sites where it is known or suspected to be produced) must be managed throughout the life time of the landfill, including the period after landfill completion (typically fifteen to twenty years after closure; often longer).

b) The following elements must be present at sites receiving biodegradable wastes:



i) full containment of the site to prevent sub-surface migration and minimise surface emissions of landfill gas;

ii) an active gas extraction system to achieve

the maximum practicable collection efficiency. Passive venting of landfill gas will only be permitted where a risk assessment shows that gas emissions will prove minimal and no risk is evident to human health or the environment; and

iii) where necessary (on larger gas producing

sites) a system of combustion or other treatment process. Treatment of the gas stream pre or post combustion will be a site-specific issue based on the precise composition of the gas stream.

c) As part of the landfill gas-management strategy, gas monitoring must be undertaken. During gas monitoring, atmospheric conditions must be reported as atmospheric pressure influences gas migration. The number and location of gas-monitoring locations will be site specific. However, where the landfill has been capped, the resulting increased lateral movement of landfill gas will require more intensive gas monitoring. d) If landfill gas is found or suspected to be migrating offsite at unacceptable levels, then a landfill gas-extraction system will be required. The main pathways through which gas will migrate include:

i) high permeability strata along the bedding

plane; ii) through caves or cavities; iii) desiccation cracks in any capping media,

or at site perimeters; iv) through pathways promoted by tree roots; v) through gas or leachate wells placed for

the collection of samples or monitoring purposes;

vi) through highly fissured strata into the

atmosphere or adjacent buildings; and vii) along underground service routes.

e) The migration of landfill gas may constitute an environmental and safety risk. Methane is explosive when present in the range of five per cent (Lower Explosive limit) to 15 per cent (Upper Explosive limit) by volume in air. Gravel or sand layers, or even manmade drains, provide ideal migration routes for landfill gas, particularly after the site is capped. f) A risk assessment must be presented in all cases to identify those landfills that present an unacceptable risk due to their location, waste type, size and soil strata.

g) In line with the development of a risk assessment, the landfill Operator must also present a pre-authorisation Gas Management Plan to the Competent Agency based on the site specific risk assessment which includes details on the monitoring of:

i) expected gas composition and volume of

production at source, including quantification of trace components (estimates to be reviewed on an annual basis based upon actual monitoring information);

ii) enclosed flare emissions monitoring and

compliance assessment; and

iii) surface emissions monitoring and compliance assessment.

h) The capacity of the treatment system must be sufficient to deal with the volume of gas generated at the landfill. i) The presence of sensitive receptors near to the site boundary (within 250 metres) must be addressed within the risk assessment and environmental assessment. The need for ambient air monitoring either at the receptors or at the site boundary will also need to be considered where a potential linkage exists. j) The risk assessment will be reviewed regularly by the Operator (at least annually, or when a change in gas production is noted) in the light of analysis of trace gas components in the landfill gas, and of any changes in operation, such as new waste streams. A record of this review will be kept by the Operator for the life of the active landfill. k) Periodic monitoring of emissions from any flares or energy recovery engines utilised on site must be supported by periodic assessment of the source gas composition at the landfill site as this can indicate the impact of gas emissions on the environment. l) Where odour problems are encountered the gas extraction system should be reviewed with increased ambient air monitoring using methane as a landfill gas indicator.

m) Leachate recirculation is permissible on site to provide for promoting biological activity as the anaerobic bacteria necessary for gas production are found within the leachate. Leachate must only be recirculated where it forms part of the overall gas management plan and must not be seen as an inexpensive way of disposing of leachate. n) Leachate recirculation must not take place until the landfill gas extraction system is in place to collect and treat the gas generated. o) All flaring or combustion engine equipment utilised on site to manage gas or to recover energy must be designed to meet the following requirements:



i) discharges should be vertically upwards and unimpeded by cowls or any other fixture on top of the stack;

ii) sampling sockets should be fitted to allow

for ease of monitoring; iii) crankcase emissions from engines must

be managed to minimise release to the environment;

iv) there should be continuous assessment of

methane and the rate of flow of the inlet gas;

v) sampling must be undertaken after

combustion is completed (i.e. downstream of the flame); and

vi) flare designs must include sufficient

shroud to fully enclose the flame at all times.

p) All design works relating to landfill gas management and utilisation must be undertaken by a duly qualified Chartered Engineer with demonstrable relevant experience of undertaking such works. q) Monitoring of landfill gas must be undertaken throughout the lifetime of the landfill. Monitoring should be undertaken on a monthly basis throughout the operational period of sites accepting biodegradable waste. r) Monthly monitoring will be required post-completion for a period as determined through the risk assessment and agreed with the Competent Agency. Key to monitoring frequency is the proximity to sensitive receptors.

s) Landfill gas completion, following site closure, can be considered as having been met when the methane concentration remains below 0.5%v/v and carbon dioxide concentration remains below 0.5%v/v for a period of at least 24 months, including on at least 4 occasions when atmospheric pressure was falling. t) Monitoring of the following parameters using electronic monitors calibrated for the purpose is required:

i) methane (% v/v);

ii) carbon dioxide (% v/v);

iii) oxygen (% v/v); and

iv) atmospheric pressure (mb).

u) The results of landfill gas monitoring, alongside details of site location, monitoring hole number and date of monitoring must be recorded and kept available for review by the Competent Agency as required. Full records should be maintained in both paper and electronic format from site opening through to agreed site completion.

5) Landfill Capping

a) Leachate formation within a landfill is controlled in the long term through the provision of a landfill cap which provides a surface seal for the site and limits infiltration into the landfill. Hazardous and non-hazardous landfills will normally require a cap. Landfills for inert waste will not normally require a cap. b) Table 3 provides a guideline for the capping requirements on landfills for different waste types.

Table 3: Landfill Capping Requirements Landfill Category

Inert Non Hazardous

Hazardous

Gas Drainage Layer

Not Required

Required Not Required

Artificial Sealing Liner

Not Required

Not Required

Required

Impermeable Mineral Layer

Not Required

Required Required

Drainage Layer ≥ 0.5 metres

Not Required

Required Required

Top Soil Cover ≥ 1 metre

Not Normally Required

Required Required

c) The Landfill Operator must determine the appropriate sealing layer on the basis of the hydrogeological and landfill gas risk assessments. Cap design must take account of the:

i) balance between the requirement to

minimise leachate generation and the need to flush contaminants from the waste;

ii) containment of landfill gas; and

iii) need to physically separate some wastes

(for example, asbestos) from the environment.

d) As a minimum, the capping system for a non-Hazardous or Hazardous landfill must contain:

i) a sealing layer;

ii) a surface water drainage system; and

iii) cover soils.

e) The requirement for a gas drainage layer will depend upon the site-specific gas extraction system. In most landfills accepting biodegradable wastes retro-drilled landfill gas extraction boreholes are the preferred method of gas management.



f) The finished surface of the landfill cap should have a slope of at least 5% to allow for the management and control of runoff, and to make provision for differential settlement over time.

6) Landfill Stability

a) Waste is unlikely to be a geotechnically homogeneous material and as such, due consideration must be given to the stability of waste and potential settlement over time as it is subject to decomposition, consolidation, and considerable variation, both spatially and with time. b) Stability and settlement must be monitored in the construction, operational and aftercare phases. The Operator must justify any assumptions and should undertake appropriate sensitivity analysis.

c) The stability and settlement of the waste, the constructed landform, its foundation and the environmental management infrastructure, and the interactions between them, must be assessed by a suitably qualified engineer to demonstrate that the environmental management infrastructure will not be compromised. In addition, there must be no promotion of any risk to safety or detriment to the landform over the entire lifecycle of the landfill. d) In completing this assessment the Operator must take account of:

i) settlement or slippage within the

foundation (sub-grade) beneath the landfill base or sides;

ii) slippage within the liner system; iii) slippage at the waste/liner interface; iv) rotational failure within the waste, or

through the whole cross-section; v) slippage failure of the cap or of its

components; vi) effects of settlement on the landfill cap

and restoration; vii) effects of settlement on environmental

management infrastructure; and viii) the presence and movement of waste and

leachate.

e) For municipal waste and industrial and commercial waste general considerations which minimise the impact of settlement include:

i) a maximum finished slope of 1 vertical to

4 horizontal; and

ii) temporary slopes between phases of a landfill of 1 vertical to 2 horizontal to 1 vertical to 3 horizontal.

f) Stability of a landfill can be impacted through problems at the interface between the geosynthetic and mineral liners. The interface friction must be assessed between each layer under all conditions of use; static and dynamic, temporary or permanent. g) To anticipate the effects of settlement, designers must add a surcharge to the post-settlement levels, and distinguish clearly on design drawings the ultimate post-settlement levels and the surcharged levels to which each phase of the site is to be filled, capped and restored. (Values of 15-25% are accepted as being typical of the surcharge allowance required when considering the void capacity and final pre-settlement contours of a household waste landfill).

h) Where differential settlement may occur, provision should be made to accommodate the settlement and the associated stresses, most commonly by:

i) additional thicknesses of capping

materials to accommodate differential movement or to allow removal of material if settlement does not occur as predicted; and

ii) irregular edges and boundaries to

compensate for predicted settlement differentials.

i) Additional considerations must be made for the landfilling of hazardous wastes. Whilst landfill engineering may play a role in retaining the wastes initially, such wastes should have at deposit, or achieve during the active management phase, sufficient mechanical strength for the creation of a sustainable landform in the long-term.

j) Stability assessment must take account of the site-specific circumstances, and should use geotechnical parameters appropriate to the waste material. Cohesive materials should have a bearing capacity of not less than 50 kPa. Non-cohesive waste should have an in situ bearing ratio of at least 5%.

7) Construction Quality Assurance (CQA)

a) The development and implementation of a Construction Quality Assurance (CQA) plan provides a means of demonstrating to the public and regulating authorities that the landfill being constructed meets its design requirements.

b) The CQA plan must be able to verify:

i) that materials used comply with site

specific specifications; and ii) that the method of construction/installation

is appropriate and design requirements have been met.

c) The CQA plan must contain the:



i) material/construction specifications;

ii) testing methods;

iii) testing frequency;

iv) corrective action to be taken where

necessary;

v) appropriate documentation procedures which outline what has been done.

d) The CQA must include:

i) all elements of basal containment

engineering including liners and artificially established geological barriers;

ii) sidewall lining;

iii) sub-grades for lining;

iv) liner protection;

v) all elements of the capping system;

vi) surface water and groundwater

management systems;

vii) all elements of the leachate management system including leachate extraction wells;

viii) all elements of the landfill gas

management system.

e) The production of the CQA plan, and all testing and reporting must be completed under the control of a suitably qualified Engineer, independent of the landfill site contractor/operator. On completion, a validation report should be produced and submitted to the Competent Agency which must include:

i) demonstration of CQA compliance

throughout the construction period;

ii) justifications for any changes or deviations from the agreed plan;

iii) The results of all testing - this must

include the records of any failed tests with a written explanation, and details of the remedial action taken, referenced to the appropriate secondary testing;

iv) plans showing the location of all tests;

v) "as-built" plans and sections of the works;

vi) copies of the site engineer’s daily records;

vii) records of any problems or non-

compliances and the solution applied; and

viii) any other site specific information considered relevant to proving the integrity of the landfill construction.

f) Laboratory testing with respect to CQA must be undertaken to the national standard to be defined by the Competent Agency. Typical laboratory tests on the proposed soil materials used in the construction of landfill liners are:

i) natural moisture content;

ii) particle size distribution;

iii) atterberg limits; and

iv) compaction;

v) Hydraulic conductivity.

g) Table 4 illustrates the typical parameters and testing frequencies for evaluating prospective soil liner material.

Table 4: Typical Parameters and Testing Frequencies for Soil Liner Materials Parameter Test Method

Reference Frequency Recommended

Performance

% fines (passing No. 200 sieve)

ASTM D1140 1 per 1000m3 1 test each day soil is excavated or placed

≥ 50%

% Gravel (Dry weight retained in N0. 4 sieve)


≤ 10%

Atterburg Limits


Density Index ≥ 50%

Water Content

ASTM D3017 ASTM D4643 ASTM D2216 (at least every 5th sample)

1 per 1000m3 1 test each day soil is excavated or placed

Article VI - Operations

1) Working Plan

a) A Site Specific Working Plan, required in accordance with the site specific waste management licence application must be developed and forwarded to the Competent Agency for review and agreement prior to operations commencing on the site.



b) The Working Plan will constitute the documentary procedures which will be used to control all aspects of work on site. Issues to be considered and included within the Working Plan are outlined below in the following sections.

2) General Filling Requirements

a) All Landfills must be filled in a series of independent tipping areas or cells, each taking less than two years to fill, after which they will be immediately closed and made ready for their proposed post-closure use which will be determined at the site planning stage. b) In the case of trench-and-fill landfills, each trench must be sized to ensure that it is filled within two years. Larger excavations for trench-and-fill landfills must be filled on a cellular basis. c) Where landfill or large trench-and-fill excavation is to be filled as a series of cells, prudent location of cells is required to:

i) provide stability for a batter or

embankment;

ii) provide a screen of the landfill operations from view;

iii) reduce groundwater flow into the site;

iv) shed runoff into the surface water system;

v) minimise the need to constantly construct

roads within the site;

vi) avoid active landfilling near areas being developed for residential purposes; and

vii) align them perpendicular to the prevailing

wind to reduce litter.

d) Waste must be levelled and compacted as soon as it is discharged at the working area. e) A density following initial compaction of about 0.8 tonnes/m3 is the optimum for instigating biodegradation processes. f) Daily cover assists in preventing materials becoming windblown, deterring scavengers, birds and vermin, and improving the site's visual appearance and the Landfill Operator must ensure that waste is covered as soon as practicable. g) The Operator’s risk assessment should identify any wastes which have characteristics that require a particular method of handling at the site which is not part of normal day to day procedures. Typical examples are:

i) fine particulate material;

ii) empty containers;

iii) oversize objects;

iv) sludges;

v) very light materials, for example expanded polystyrene; and

vi) foul smelling wastes.

h) Consideration should be given to pre-treatment of such wastes such as to reduce the handling difficulties posed by such wastes. i) The Operator must consider the prevailing wind direction and strength when planning the filling direction and sequence as this will assist in the general reduction of nuisance caused by odour, dust, litter and noise. Careful phasing is critical in minimising these airborne emissions.

3) Waste Acceptance

a) Waste will only be accepted at a landfill which is duly authorised to accept that waste as laid out in Part 1 of this Standard. b) Waste Acceptance will be determined in accordance with the provisions as laid down in the Waste Classification Standard and the Waste Acceptance Criteria Standard.

4) Unacceptable Loads

a) All loads which fail to meet the Waste Acceptance Criteria for the type of wastes allowable at a landfill site must be managed in accordance with the requirements of the Waste Acceptance Criteria Standard.

b) Full details of all materials held within the quarantine area must be kept. As a minimum the following records must be held for each and every load:

i) date of arrival;

ii) details of the source of the waste and the

company bringing the waste to the site;

iii) a copy of the Waste Tracking Form (see Regulatory Control and Compliance Standard provisions. If no Waste Tracking Form is provided then it will automatically be deemed unacceptable until the appropriate documentary evidence has been provided); and

iv) where relevant, the accompanying

Hazardous Waste Code.

c) All labelling must be resilient enough to stay attached and legible throughout the whole time of storage at the installation. d) A daily inspection of the condition of containers and pallets must be undertaken and written records



kept of these inspections. If a container is found to be damaged, leaking or in a state of deterioration, it must immediately be over-drummed or the contents transferred to another container or processed. e) All spillages of hazardous wastes must be logged. Where spillages are greater than 200 litres the Competent Agency must be informed. f) Containers must be stored in such a manner that leaks and spillages could not escape over bunds/edge of the sealed drainage area.

5) Operations and Maintenance

a) As a minimum, effective operational and maintenance systems must be employed on all aspects of the site where failure could impact on the environment. There must be:

i) documented procedures to control

operations that may have an adverse impact on the environment;

ii) a defined procedure for identifying,

reviewing and prioritising items of plant for which a preventative maintenance regime is appropriate;

iii) documented procedures for monitoring

emissions or impacts; and

iv) a preventative maintenance programme covering all plant, whose failure could lead to impact on the environment.

b) The maintenance system should include auditing of performance against requirements arising from the above and reporting the result of audits to senior management. Auditing and inspection records must be maintained for a minimum of 5 years, and provided to the Competent Authority or their designated representative, when requested.

6) Competence and Training

a) The Technical Competence and training of operatives involved in landfilling must be undertaken in accordance with the Waste Training and Assessment of Technical Competence of Operators Standard. b) Additional training must be provided to all staff working within the confines of the landfill with respect to:

i) Health and Safety and the individual

responsibilities that all have for the safety of others;

ii) Understanding of the environmental

impacts that their work could have and provision of instructions to assist in reducing these impacts.

7) Accident Plans

a) An Accident Plan must be put in place by the Operator (reviewed at least once every three years, or in the event of an accident) which identifies:

i) the likelihood and consequence of

accidents; and ii) actions to prevent accidents and mitigate

any consequences.

b) The Accident Plan will:

i) identify the potential on-site accident hazards;

ii) provide an assessment of the risks;

iii) identify necessary risk management

measures;

iv) specify the risk management measures that are used at the landfill;

v) include contingency actions to be

undertaken in the event of an accident to mitigate consequences; and

vi) make provision for the hazards displayed

by any hazardous wastes accepted at the landfill.

c) Particular areas of accidents to consider at landfills may include, but should not be limited to, the following:

i) uncontrolled migration of landfill gas; ii) fire;

iii) explosion;

iv) waste slippage; v) Failure of a basal or side wall liner; vi) incompatible wastes coming into contact

with each other;

vii) release of leachate to an uncontained area;

viii) overfilling of tanks / lagoons; ix) emission of a treated leachate before

adequate checking of its composition; and x) vandalism.

8) Compliance Reporting

a) Written procedures must be in place for handling, investigating, communicating and reporting actual or potential non-compliance with operating procedures.



b) There must be written procedures for handling, investigating, communicating and reporting environmental complaints and implementation of appropriate actions. c) There must be written procedures for investigating incidents, (and near misses) including identifying suitable corrective action and follow up.

9) Site Security

a) The facility must be secured to prevent free access to the site. b) The gates of the facility must be locked outside operating hours. c) Access to each facility must be controlled by systems to detect and discourage illegal dumping at the facility.

10) Noise

a) Measures must be taken to minimise the nuisance arising from the landfill in relation to noise pollution. These requirements are additional to the National Environmental Noise Standards. b) Where noise issues are likely to be relevant, the Operator must provide information on the following:

i) the main sources of noise and vibration

that will fall within the installation and also on infrequent sources of noise and vibration;

ii) operating timescales of the landfill;

iii) the nearest noise-sensitive sites; iv) conditions/limits imposed under other

regimes;

v) the local noise environment;

vi) any environmental noise measurement surveys, modelling or any other noise measurements; and

vii) any specific local issues and proposals for

improvements.

c) Where there are sensitive receptors present, a Noise Management Plan must be developed which provides details on how noise will be managed within the site and the measures to be adopted to reduce those noise impacts.

11) Control of Air-borne Nuisance

a) Measures must be put in place to minimise the nuisance arising from the landfill in relation to:

i) emissions of dust;

ii) wind-blown materials; and

iii) the formation of aerosols.

b) Site operations must have due regard to the need to control dirt originating from the site being dispersed onto public roads and the surrounding land. c) All of the potential impacts of a landfill site must be identified during conceptual model development and refined at the pre-development stage. Detailed measures to mitigate the impacts must be included in the landfill design and set out in the Working Plan. d) As a minimum, procedures must be in place to deal with particulate matter arising from:

i) the placement of wastes;

ii) traffic on site roads;

iii) site preparation and restoration

activities;

iv) surface emissions; and

v) carriage of dust/mud onto the highway.

e) Dust suppression must be provided including the availability of bowsers and water supplies. Leachate must not be used for dust suppression in areas outside the working landfill area, although it may be suitable for use for dust suppression within the working face.

12) Odour

a) Odour is typically associated with trace components in landfill gas, the handling of odorous wastes and inadequate emplacement and covering of biodegradable wastes. The management of odour will include procedures dealing with:

i) waste materials, such as wastes from

TSD Facilities, which have decomposed significantly prior to landfilling;

ii) old waste disturbed by digging; iii) foul smelling wastes; iv) agricultural and sewage treatment

residues; v) leachate and leachate treatment systems;

and vi) landfill gas.

b) Procedures must be put in place to maintain:

i) information relating to sensitive receptors;



ii) a description of the types of odorous

substances deposited/disposed of; and iii) a description of the point, linear or area

sources of release.

c) As part of the Working Plan an Odour Management Plan must be developed and maintained including:

i) control measures to prevent or control

odour;

ii) demonstration/justification that there will not be an odour problem under normal conditions;

iii) a description or copy of any conditions or

limits put in place by the Competent Agency which relate to the prevention or minimisation of odour;

iv) identification of the actions to be taken in

the event of abnormal events or conditions which might lead to odour, or potential odour problems;

v) an understanding of the impact in the

event of abnormal events or conditions; vi) monitoring undertaken; and vii) communication with local residents if an

odour problem arises or is likely to arise.

d) A regular odour impact assessment must be undertaken by the Operator. The impact assessment must cover a range of reasonably foreseeable odour generation and receptor exposure scenarios and the effect of different mitigation options. The Assessment must include point sources (for example flares) as well as linear or area sources (tipping faces, cracks in the cap).

e) Special consideration must be given to the following to assist in minimising odour problems:

i) sulphate wastes must be disposed of in

cells in which biodegradable waste is not accepted;

ii) there must be co-ordination between the

gatehouse and Operators at the tipping face where known odorous wastes are to be deposited;

iii) excavation of waste or removal of cover

(during for example, the installation of gas wells, or for other operational needs), may give rise to odours; and

iv) tipping areas must be kept as small as

possible, and waste must be covered as soon as possible following deposit.

13) Control of Birds

a) Procedures must be put in place to deal with the presence of scavenging birds including one or more of the following:

i) flying birds of prey over the site;

ii) bird kites mimicking birds of prey;

iii) explosive devices as bird scarers;

iv) scarecrows - fixed or mobile;

v) amplified recordings or electronic

representations of bird distress calls (species specific); and/or

vi) bird corpses or dummies.

14) Control of Other Pests and Vermin

a) The Operator must make use of one or more of the following measures to deal with pest infestation:

i) effective site management involving

prompt emplacement, compaction and covering of wastes in well-defined cells;

ii) intermediate capping and prompt capping

of completed areas;

iii) ensuring previously employed waste is not disturbed, exposed or moved;

iv) regular visits by pest control contractors or

fully trained operatives; and/or

v) inspection and treatment of areas where rats live, for example sewers, culverts and drains.

b) Insect infestations commonly arise from waste which has been awaiting collection for some time. Procedures must be put in place to prevent or limit the acceptance of such wastes. The Operator should reduce the risk of infestation by prompt burial of such wastes in order to interrupt the reproductive cycle of the insect. The potential for insect infestation to develop should also be considered if engineering works require waste to be re-excavated. c) Baboons are a particular problem on some landfill sites within the Kingdom. As well as standard site management practices such as outlined in paragraph a) above, trained staff should be provided at all such sites to reduce baboon/ operational staff clashes. Staff would be required to:

i) survey the site every morning prior to operations commencing to identify baboon activity;

ii) utilise provided equipment to scare

baboons from the site;



iii) provide operational support throughout the

day to keep baboons out of the site during operational hours.

d) These trained staff should be provided with access to:

i) explosive devices to scare baboons from the site;

ii) long whips which provide a loud noise;

iii) amplified recordings or electronic

representations of baboon distress calls.

15) Fires

a) The primary causes of landfill fires are:

i) vandalism and the direct setting of fires on

the site; or

ii) poor practice in the management of landfill gas.

b) Control measures must be put in place to prevent fires including:

i) site security to prevent unauthorised

access;

ii) prompt emplacement, compaction and covering of wastes in well-defined cells;

iii) prompt capping of completed areas;

iv) good management of landfill gas and

prevention of air ingress into the waste and gas extraction and collection systems; and

v) waste acceptance procedures should

preclude the acceptance of hot or reactive wastes.

c) All fires must be reported to the Competent Agency and must be extinguished as soon as possible.

16) Control of Leaks and Spillages

a) The management of spillages at the landfill must be undertaken with due regard to both the hazard and the volume. b) Where spillages of dry wastes occur, these must be cleared by either manual or mechanical means, for example handpicking, sweeping or shovelling, depending on the size and location of the spillage. c) Minor spillages of liquid must be contained using spillage kits or any suitable readily available absorbent material. This material must be disposed

of in a manner appropriate to the type of material absorbed. d) A record must be maintained in the site diary of any spillages so treated. e) In the event of a major spillage the site drains must be sealed off where possible and a specialist contractor brought on site to clear the spillage. f) The Competent Agency must be informed of any major spillage event and a record made in the site diary. g) Spillage kits and other emergency equipment must be stored in the appropriate areas of the site. The Competent Agency must be informed of the location and content of this equipment prior to the commencement of waste treatment operations at the site.

17) Groundwater Protection

a) Throughout the filling of the landfill continuous sample collection and laboratory analysis must be undertaken with due regard to the provisions in Appendix 4. b) Groundwater is to be collected from suitably installed monitoring positions both up stream and down stream of the landfill. The results of analysis must be reviewed and interpreted by suitably qualified staff who can identify whether there are potential negative impacts upon the underlying groundwater which could indicate a failure in the existing lining systems. c) Continued regular monitoring must be undertaken throughout site operations and also post-closure to ensure that the landfill does not negatively impact upon the underlying groundwater resources.

Article VII – Record Keeping

1) Waste Movement Records

a) A record of the types and quantities (in tonnes) of wastes received at the site, and wastes/process products removed from the site must be maintained and kept in the site office. b) A summary of the types and quantities of wastes deposited at the site and waste residues removed from the site must be provided to the Competent Agency at an agreed frequency and in an agreed format.

2) Records of Significant Events

a) The following significant events must be recorded, on site:



i) the start and finish of any construction and engineering works undertaken on site;

ii) start and finish of waste management

processes carried out on site;

iii) maintenance;

iv) breakdowns;

v) emergencies;

vi) problems with waste received and action taken;

vii) site inspections;

viii) attendance of technically competent

management on site;

ix) despatch of records to the Competent Agency;

x) severe weather conditions;

xi) complaints; and

xii) pest or vermin incidents.

b) The Site Manager or nominated person must maintain a record of the above information in the site diary as required. c) The site diary must be kept in the site control office at all times and made available for inspection at all reasonable times by any officer of the Competent Agency.

3) Format of Records

a) The terms Record, Log Book and Site Diary may be kept as, but not limited to:

i) hand generated log; ii) computer generated hard copies; iii) floppy Disc; and/or iv) on an unalterable disk or similar format.

4) Security of Records

a) To ensure the security of records they must be housed in either locked containers or kept in offices that shall be locked when not attended.

5) Archiving of Records

a) Copies of all records relating to wastes movements and product sales must be kept by the Site Manager for at least 3 years, before archiving.

b) Archived records should be kept by the Site Manager for a period of 12 years following site closure.

Article VIII – Site Closure and Aftercare

1) Site Closure Plan

a) The Operator is required to develop and maintain a Site Closure Plan which will include evidence of the following:

i) confirmation of the site capping detail

including performance characteristics;

ii) detailed information on the leachate and gas collection system and its performance throughout the filling operations. Issues to be included relate to the proposed end date for completion of leachate and gas control;

iii) monitoring plan for the site with respect to

leachate (and underlying groundwater) quality and gas production to ascertain when site completion has been achieved (that is, when significant leachate production has ceased and landfill gas monitoring indicates low concentrations of Methane and Carbon Dioxide over a two year period);

iv) removal or the flushing out of pipelines

and vessels where appropriate and the complete emptying of any potentially harmful contents;

v) plans of all underground pipes and

vessels;

vi) the method and resource necessary for the clearing of lagoons;

vii) methods of dismantling buildings and

other structures; and viii) testing of the soil to ascertain the degree

of any pollution caused by the activities and the need for any remediation to return the site to a satisfactory state as defined by the initial site report.

b) The Site Closure Plan must be reviewed at least once every three years. Other triggers for the review of the Site Closure Plan would include any proposed changes to the phasing of the landfill. The Plan should be kept updated as material changes occur.



2) Monitoring

a) Monitoring plays a vital part in determining the performance of the landfill against any assumptions made and the annual reviews must consider the progress made towards the initial completion criteria. b) The Operator must review the completion criteria including the following factors (once every three years or where significant deviation from the expected performance is identified):

i) Quality and quantity of leachate

production (both throughout closure and post-closure of the landfill);

ii) Impact of leachate on the underlying

groundwater quality, taking into account the parameters outlined in Appendix 4;

iii) Generation, flow and concentration of gas;

iv) Trace composition of the gas;

v) Potential for leachate or gas to be

generated in future;

vi) Physical stability of the waste and associated structures;

vii) Presence of particular problem wastes

which could present a risk in the future.



The report must describe the design parameters of the landfill site and must contain as a minimum details of the following:

(i) Legal details for ownership of the site (ii) An up to date plan and description of the site

and the area within 500 metres of the site that covers: a. all property and property boundaries b. all buildings, roads and utility corridors c. land contours, surface water drainage,

water bodies, rights-of-way and other easements,

d. forested areas, e. land uses and land use designations, and f. property conditions not otherwise covered

in subclauses (a) to (e) (iii) A plan and description of the waste fill area,

base contours for waste disposal, base contours for any leachate collection system, top contours for waste disposal and top contours with final cover

(iv) Details of the total waste disposal volume (v) A materials balance between the sources of

soils, on or off the site, and the uses of soils on the site

(vi) A full hydrogeological assessment of the suitability of the site for the landfilling of municipal waste or other waste that considers the geologic and hydrogeologic conditions of the site, the design of the site and the monitoring and contingency plans

(vii) A full geotechnical assessment of the suitability of the site for the landfilling of municipal waste or other waste that considers bearing capacity, differential settlement and slope stability during construction, operation and after closure, and that addresses the potential effects on any liner or leachate collection system

(viii) A description of the expected quality and quantity of leachate

(ix) Detailed plans, specifications and descriptions of any liner system necessary to control leachate, including construction and quality assurance and quality control procedures for the liner materials and liner system installation

(x) Detailed plans, specifications and descriptions of any leachate collection, treatment and disposal system necessary to control leachate, including construction and quality assurance and quality control procedures for the system components and system installation

(xi) An assessment of the potential for subsurface migration of landfill gas at the site and of any control system necessary for monitoring or controlling the migration

(xii) A detailed assessment of the potential impacts on surface water features that may be caused by the site or operations at the site

(xiii) Detailed plans, specifications and descriptions of any system necessary for controlling landfill

(xiv) gas by venting it or by collecting and burning

or using it, including construction and quality assurance and quality control procedures for the system components and system installation

(xv) Detailed plans, specifications and descriptions of the system for collecting, directing and discharging surface water, including details of any sediment control or other features and including construction, quality assurance and quality control procedures for the system components and system installation

(xvi) Detailed plans, specifications and descriptions of monitoring facilities for leachate, ground water, surface water and, where appropriate, landfill gas

(xvii) An assessment of potential noise impacts due to operations at the site and to local trucking related to operations at the site, including an evaluation of any proposed noise control measures

(xviii) An assessment of potential visual impacts on nearby properties due to the site and site operations

(xix) Detailed plans, specifications and descriptions of the buffer area and ancillary facilities, including any screening, landscaping, fencing, weigh scales, buildings, structures, access roads, internal roads, holding areas for cover material, holding areas for rejected waste or materials for recycling, and other holding areas

(xx) Detailed plans, specifications and descriptions of the contaminant attenuation zone, if one is necessary

(xxi) An estimate of the contaminating life span of the site with respect to contaminants involved in the subsurface migration of landfill gas and an estimate of the service life of any engineered facilities associated with the subsurface migration of landfill gas

(xxii) An estimate of the contaminating life span of the site with respect to contaminants in leachate

(xxiii) An estimate of the service life of every engineered facility associated with leachate

(xxiv) Details of any facilities intended to control or change the contaminating life span of the landfilling site

(xxv) Contingency plans that can be implemented to control and dispose of leachate produced in a quantity greater than expected or with a quality worse than expected, including specifications and descriptions in sufficient detail to demonstrate the feasibility of the plans

(xxvi) Contingency plans that can be implemented to control and dispose of landfill gas migrating in the subsurface in a quantity greater than expected or with a quality worse than expected, including specifications and descriptions in sufficient detail to demonstrate the feasibility of the plans

Appendix 1

Pre-Design Report Requirements for Authorisation



(xxvii) A description of the source, nature and quality of daily cover, including, with respect to material not normally used for daily cover, a discussion of its benefits and limitations, a description of quality assurance and quality control procedures for daily cover and a description of application rates and application procedures for daily cover, including the frequency and timing of application of daily cover if other than at the end of each working day

(xxviii) A description of the nature, quality and quantity of final cover, including construction details and quality assurance and quality control procedures for the materials to be used and their installation

(xxix) A site closure plan, including details of the proposed end use of the site, the appearance of the site after closure, revegetation, landscaping, the construction of new facilities, and the removal of existing facilities to facilitate closure, post-closure care and site end use

(xxx) A summary of the main characteristics of the landfilling site, including the maximum daily quantity of waste that will be accepted for disposal, the estimated annual average quantity of waste that will be accepted for disposal, the area of the landfilling site, the area of the waste fill area, the total waste disposal volume, the estimated waste disposal capacity in tonnes, any subcategories of municipal waste that are not expected to be received or that will not be accepted for disposal, and the estimated date of site closure.



An environmental assessment of the site proposed for landfill is required to gain a thorough understanding of the existing environment at the site in order to develop a sound landfill design. This assessment must examine the impact of the proposed landfill on the air, groundwater, surface water and noise environments, and should be based on at least two to three years of data. If, following an environmental assessment, the site is identified as unsuitable for a landfill, the proposal should not proceed any further. For the purposes of siting a landfill site, an environmental assessment should contain:

(i) Meteorological data, including monthly rainfall, monthly evaporation, seasonal wind strength and direction

(ii) Hydrogeological assessment in accordance with EPA Publication Hydrogeological Assessments (Groundwater Quality), which includes: a. local and regional geology b. spatial distribution of groundwater (local

and regional if watertable is artificially depressed)

c. depth to groundwater (current and after any rebound if the watertable is artificially depressed) and watertable elevation (mAHD)

d. groundwater gradient and flow direction e. description of groundwater interaction with f. local surface waters g. aquifer physical properties:

i. permeability ii. aquifer thickness iii. saturated thickness iv. porosity.

h. aquifer chemical properties: i. mineralogy ii. cation exchange and sorption

capacity. i. groundwater quality (local and regional if

aquifer is likely to have been impacted on by previous activities)

j. beneficial uses of groundwater to be protected

k. groundwater use in the surrounding area l. predicted extent and degree of impacts on

groundwater quality during and after the landfill operation

m. verification that beneficial uses are not adversely impacted at the site, or at the boundary of an attenuation zone where designated.

(iii) Water Management, including: a. water balance for the site and estimated

volume of leachate to be generated b. leachate collection, storage facilities,

treatment and disposal

c. stormwater diversion banks and/or cut-off drains and storage dams

d. fire-fighting equipment and water supply e. wheel washes.

(iv) Landfill gas and odour control, including: a. availability of cover material onsite b. anticipated volume and rate of landfill gas

generation c. potential users of landfill gas d. impacts of landfill gas on greenhouse gas

emissions e. risk posed by migration of gas.

Appendix 2

Environmental Assessment Requirements



Appendix 3

Properties of Different Geomembrane Types

HDPE High density polyethylene LLDPE Linear low density polyethylene PVC Polyvinyl chloride EPDM Ethylene propylene diene monomer EIA-R Ethylene Interpolymer Alloy – Reinforced CSPE-R Chlorosulphonated polyethylene – Reinforced FPP Flexible polypropylene



Appendix 4

Dangerous Substances and Groundwater Quality

LIST I OF FAMILIES AND GROUPS OF SUBSTANCES List I contains the individual substances which belong to the families and groups of substances enumerated below, with the exception of those which are considered inappropriate to List I on the basis of a low risk of toxicity, persistence and bioaccumulation. Such substances which with regard to toxicity, persistence and bioaccumulation are appropriate to List II are to be classed in List II. 1. Organohalogen compounds and substances that may form such compounds in the aquatic environment 2. Organophosphorus compounds 3. Organotin compounds 4. Substances which possess carcinogenic, mutagenic or teratogenic properties in or via the aquatic environment. Where certain substances in List II below are carcinogenic, mutagenic or teratogenic, they are included in category 4 of this List. 5. Mercury and its compounds 6. Cadmium and its compounds 7. Mineral oils and hydrocarbons 8. Cyanides LIST II OF FAMILIES AND GROUPS OF SUBSTANCES List II contains the individual substances and the categories of substances belonging to the families and groups of substances listed below which could have a harmful effect on groundwater. 1. The following metalloids and metals and their compounds:

Zinc Selenium Tin Vanadium

Copper Arsenic Barium Cobalt

Nickel Antimony Beryllium Thallium

Chromium Molybdenum Boron Tellurium

Lead Titanium Uranium Silver

2. Biocides and their derivatives not appearing in List I. 3. Substances which have a deleterious effect on the taste and/or odour of groundwater, and compounds liable to cause the formation of such substances in such water and to render it unfit for human consumption. 4. Toxic or persistent organic compounds of silicon, and substances which may cause the formation of such compounds in water, excluding those which are biologically harmless or are rapidly converted in water into harmless substances. 5. Inorganic compounds of phosphorus and elemental phosphorus. 6. Fluorides. 7. Ammonia and nitrites.

En EnvStand16 Landfill-Design & Operation

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