The diversification of HG Leach into the solid waste business in 1999 coincided with the closure of numerous dumps and small landfills in the region. The introduction of the RMA (Resource Management Act) required all local Councils to either upgrade or close many of the small disposal sites and to engineer these to sufficient standards to ensure environmental compliance.
This significant change offered HG Leach the opportunity to further use its skills, knowledge and resource base to make the most of contracting opportunities in the waste industry.
HG Leach has used its skills to undertake contracting works in the following areas:
landfill operations at Matamata Landfill until its closure in Dec 2001
closure and capping works at the Cambridge, Athenree, Matamata,
Morrinsville, Thames and Tirau Landfills for various District Councils
environmental protection works and leachate cut-off systems at Cambridge and Athenree Landfills
construction of the Tirohia, Rotorua, & Silverstream Landfills,
which are state of the art modern landfills built to the highest
specifications including composite lining, leachate and gas
collection systems.
The contract comprised construction of formation and lining works.
The work included:
Site clearance and excavation of unsuitable material for the
side slopes of the new landfill
Construction and maintenance of sediment control measures
Disposal of unsuitable material
Bulk earthworks for the formation of the sides slopes
Groundwater drainage construction
Placement of backfill material for the formation of the base
and side slopes
Disposal of surplus material
Excavation of suitable material from designated borrow areas
for backfill and liner requirements for the base and side slopes
Placement of soil liner components on base and side slopes
Supply and installation of geosynthetic liner components
on the base and side slopes
Leachate diversion works
Leachate drainage works
Construction of a temporary toe bund and associated works
Construction of access road
Total volume of earthworks – 135,000 cubic metres
Geogrid rockfill walls – 2700 square metres
HDPE landfill liner – 22,000 square metres
600 mm compacted clay liners – 18,000 square metres
1,800 sqm of non fines concrete walls overlain by synthetic liners
8,000 square metres of landfill drainage blankets 500 mm thick
HG Leach has specific experience in dealing with the challenges associated with contracting in the waste industry. Hazards are found in this industry which make specialist contracting vital to a successful outcome. These hazards can include:
. high depth of refuse requiring rework
. unstable underfoot conditions resulting in plant or vehicles overturning
. safety issues working near heavy plant and machinery
. release of landfill gases - especially methane
. contaminated water / leachate
. fire risk working on a landfill
. dangerous materials in the landfill which can cause injury
. odour
. vermin
. hepatitis and tetanus risks
. excavation in water
. excavation greater than 1.5 metres deep - OSH notification.
The company incorporates its Health and Safety System into all works, and each site is managed according to the Health and Safety Plan to ensure a safe work place.
Environmental responsibility is at the forefront of every HG Leach operation, including contracting. To ensure all HG Leach contracting works meet environmental requirements, the company also undertakes all its contracting works in compliance with:
. the Resource Management Act
. the Conditions of Consent for the site
. contract specifications.
The company prides itself on effective project management and quality assurance procedures, ensuring the environmental protections that clients seek are achieved on time and to budget.
