Andrew Greenall & Bill Green, Castings Technology International

LAND CONTAMINATION AT
FOUNDRY SITES
Andrew Greenall & Bill Green

Contamination occurs:
From handling raw materials and wastes
From air deposition both on and off the site
Constructing a Conceptual Model will help us to
understand the distribution across the site.

Section through F E Caster and Sons Foundry Ltd, operating since
the early 20 th Century
Starting with a simple cross section we
can begin to develop our model.

For each issue we’ll consider:
Sources
- Scrap, raw materials and waste handling
- air emissions
- made ground (historic)
Pathway
-deposition to ground/surface water
-leaching and migration to water
-contact (human)

Raw materials
Metallic inputs
•Ingots –typically clean, packaged – low potential
•Scrap – may be poorly graded, dirty - high potential
Metals – aluminium, bismuth, boron, cadmium,
chromium, copper, lead, nickel, selenium, brass/bronze.
Non-metals – oil, PAH, PCB, cutting fluids, paints.

Let us put these on our model…
dust
scrap
ingots
Metals
and oils

Mould and coremaking materials
Sands Silica
Chromite
Zircon
– predominantly inert
– high chrome, but in a stable form
– low radioactivity, OK for landfill
Binders Greensand – coal dust (metals, PAH, sulphates)
Chemical
– most based round phenolic resins
Phenols soluble, but degrade rapidly
at low concentrations
Others may contain PAH (Urethane)
or acids (Furane)
Early systems organic and unlikely to have left contamination.

Greensand
silo
Liquid
binder
system
Sands and binders can leak inside and outside of
foundry during delivery, storage and use

Oils/Fuels
• Coke – Cupolas
• Gas oil – Heating (Furnaces and buildings), vehicle
fuel
• Oils – Lubrication, insulation, hydraulics, quenching
• Solvents – Coatings, paints, release agents
• Chlorinated – degreasing
Others
• Petrol, PCBs
Main contamination potential during bulk transfer and
storage tank leakage – especially underground

Underground diesel
refuelling tank

Wastes
Abatement wastes
• Cupola – dusts and sludges – metals, PAH, (PCDD/F)
• Fettling – metals associated with alloys produced
Melting waste
• Slags – CaO, MgO, metal oxides, alkaline
• Cupola bottom ash – coke dust, metals
• Non-ferrous dross metals, fluorides
Other wastes
• Sands – silica dust, phenol, PAH
• “Empty containers” – resins, oils, solvents etc
• Building Wastes – Asbestos

Waste
sand
Disused sludge
lagoon
Abatement
dust spillage
Leak from
“empty drum

Non-direct pathways
Deposition from air emissions - melting
• Metals melted and their alloy constituents
• Contaminants from scrap – PAH, PCDD/F from
combustion, PCB.
• Refractories, fluxing agents – fluorides and chlorides
Also from
• Finishing, fettling etc – metals and their oxides
• Sand plants, knock out, reclamation – silica, binders,
coal dust.

Current air emissions, as regulated, should not have an
impact - but historically they may have.
Identifying historic deposition
Most impacts will be historic – it can be useful to model
the deposition, thereby allowing a prediction of where
the highest levels may be.

HISTORIC DEPOSITION
12 tonnes/hour cupola,
1400
1200
Tot ug/m2/sPM Cupola 1hr
No abatement,
18 m stack,
12 m building.
1000
800
600
70.00
60.00
50.00
Metres
400
200
0
-200
-400
-600
40.00
30.00
20.00
10.00
5.00
2.00
1.00
-800
Prevailing wind
-1000
-1000 -800 -600 -400 -200 0 200 400 600 800 1000 1200 1400
Metres

Contamination from made ground/relics of mining
activity
As a source;
• metals, ash, clinker, sand, colliery spoil
As a pathway;
• increased porosity
• increased permeability
• un-filled mine shafts provide a direct pathway to
lower strata/groundwater

Groundwater
Made ground
Natural strata
Mineshaft
Groundwater

Conclusion
Sources
Pathways