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Swinton & Kilnhurst

LSC 305 Land Contamination, Restoration, and Revegetation

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LSC 305 Land Contamination, Restoration, and Revegetation Contents

LSC 305 Land Contamination, Restoration, and Revegetation Introduction

Contents

1. Introduction

1. Introduction........................................................................................................2

The aim of this report is to compile a series of information based on desk based methods as well as site visits. This will include a pictorial and tabulated conceptual site model highlighting the contaminants found on site and the potential source, pathways and receptor linkages. This will conclude with appropriate mitigation and remediation techniques

2. Baseline Information..........................................................................................3 2.1 Location

2.2 Previous Site Uses 2.3 Current Site 2.4 Topography 2.5 Geological Conditions

3. On Site Contaminants.......................................................................................5 4. Conceptual Model............................................................................................7 5. Pathways and Receptors..................................................................................8 6. Mitigation and Remediation.............................................................................9 6.1 What is Remediation

6.2 Techniques 6.3 Proposed Remediation

7. Conclusion..........................................................................................................11 8. References..........................................................................................................12

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LSC 305 Land Contamination, Restoration, and Revegetation Baseline Information

LSC 305 Land Contamination, Restoration, and Revegetation Baseline Information

2. Baseline Information

2.2 Previous Site Uses

2.1 Location

The Croda site is located around 4 miles north-east of Rotherham. The western border of the site lies alongside the residential areas of both Swinton and Kilnhurst with the Sheffield-Doncaster railway line segregating them. On the eastern border of the site is the South Yorkshire Navigation Canal. There are several different land uses surrounding the site, as well as the residential area. These include industrial works to the south and north-east of the site, and farmland to the east beyond the canal. Carlisle Street, which intersects the north and south areas, runs from east to west and provides access into the site.

In 1975 the company became known as Croda, and in 1981 all production ceased and became exclusively a producer of bitumen. Polymers were added to the bitumen to increase the flexibility of the product and provide a greater amount of uses. It was safer to handle compared to past chemicals but large quantities of hydrochloric acid did pose threats to the local environment. The site finally closed in 1998 and has remained unused until now, where demolition and clearance has been completed. The site can be split into two different areas, with Carlisle Street intersecting them. These will be called north and south. The majority of the works mentioned previously were carried out on the south site and it was only in the 1940’s, when the production of creosote began, that the north site was used. It was used to dispose of waste materials, particularly limes process waste, which it remained until the closure of the site.

Industrial

Residential

Historical OS maps show previous site uses. The site was previously used as a coal distillation and processing works which dated back to the 1880’s. Coke was produced as a fuel source for furnaces and used in steel production which, as we are all aware, was a massive business in the Sheffield area. Contaminants and toxic chemicals that would have been a by-product of this process include benzene and xylene, which will have been left on site. In the 1940’s creosote was being produced on site until the 1970’s when the production of tar was replaced by petroleum.

Agricultural

North Site Riv

er

Being that the land was used for so many purposes and for this length of time it will certainly be contaminated. It is the process of this report that will go about clearing the site ready for any future development.

2.3 The Current Site

Do

n

South Site

Canal

Since the closure of the site in 1998 there has been very little activity. The north area was levelled out in the late 1990’s after being filled with a series of waste products and since then a relative amount of vegetation has managed to establish itself on a thin layer of low quality soil. This could be a result of the area not being worked as heavily as the south site. There is evidence of tar and bitumen contamination where underlying low permeability has resulted in shallow, toxic ponds. The south of the site has had its built structures demolished, and because of this piles of rubble are present in certain areas, as well as some remaining concrete structures. Contamination from various areas has spread across the whole site.

2.4 Topography

It is a very flat site, with it generally lying between 18-19 metres above sea level. The north-east part of the north site is raised because of fill materials being replaced and at the south-west of the site the landform climbs 6 metres due to sandstone outcrop.

Figure 1. (above) Map showing site location and context

2.5 Geological Conditions

Between 0.5 and 2 metres of the site surface is built up of silt, sand, gravel, and demolition rubble according to the British Geological Survey. Sandstone is also apparent in the south-west and northeast of the site due to a fault in the bedrock. Below this is between 1 and 5 metres of alluvial deposits. These consist of a mix of clay, silt, sand and gravel. They are predominately made up of fine to coarse gravels which are considered to be a minor aquifer of variable permeability. Also found in these deposits, approximately 4.5 metres down, is water. Beneath this layer is Upper Carboniferous Middle Coal measures which is the solid, natural geology. This consists of series of mudstone, siltstone, sandstone, and coal up to 15 metres deep. Figure 2. (above) Site image

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Figure 3. (above) Site image

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-Where coking operations took place on site -Groundwater -Made ground -Soil -Lime slurry -Shallow sand/gravel -Underground storage tank -Where coking operations took place on site -Groundwater -Made ground -Soil -Lime slurry -Shallow sand/gravel -Underground storage tank

Xylene

Ethylbenzene

-Groundwater -Lime tips -Made ground -Transport routes

Copper

-Inhalation when air is contaminated as well as dermal contact

-Created as a by product of coal tar distilation

-Ingestion

-Inhalation and absorption

-Inhalation, ingestion, and dermal absorption

-Buildings on the site will -Inhalation. Fibres have once had asbes- can build up in tos roofs. It is likely that it lungs. would have also been present in other forms

-Found on site as copper pipes and wires

-Found in bitumen

-Found in bitumen

-Inhalation when air is contaminated as well as dermal contact

-Inhalation when air is contaminated as well as dermal contact

-Created as a by product of coal tar distilation

-Created as a by product of coal tar distilation

Main Routes of exposure

Source

Lung cancer, asbestosis, mesothelioma, benign pleural diseases

Irritation of the nose, mouth and eyes and it causes headaches, stomachaches, dizziness, vomiting and diarrhea. And possibly liver and kidney damage. cu.htm#ixzz2QZjbazMR

Has greatest effect on children due to it being absorbed easier by them. Is harmful to development.

Affects development of diabetes, cancer, vascular disease and lung disease

Affects development and also the nervous system

Can affect skin, hearing and the nervous system

Can affect blood and immune systems, and possibly the nervous system as well.

Threat

The three groups of contaminanats that are likely to remain on site are VOC’s, Heavy Metals, and Asbestos. Figure 4 shows where they may be found, how they may be exposed, and also the threats that these contaminants may carry.

There has been multiple uses for the site so for this reason there will have also been multiple contaminants released. Because of the typre of contaminants that will have been created, it is more than likely that many of them will still be present, and therefore the site will be harmful.

-Waste area -Ground layer -Soil and rubble

-Groundwater -Lime tips -Made ground -Transport routes

Lead

Asbestos

-Groundwater -Waste/lime tips -Made ground -Transport routes

Arsenic

Figure 4. (above) Contamination table

Other

Heavy Metals

LSC 305 Land Contamination, Restoration, and Revegetation On SIte Contamination

-Where coking operations took place on site -Groundwater -Made ground -Perch water -Soil -Lime slurry -Shallow sand/gravel -Underground storage tank

Benzene

VOC’s

Location

Contaminants

Group

3. On Site Contaminants

LSC 305 Land Contamination, Restoration, and Revegetation On SIte Contamination

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* * * *

* * * * *

* * * *

* * * * * * Lead

* * * * * Copper

Asbestos

*

The variety of potential contaminants left on site will have different levels of risk when linking pathways to receptors. Figure 6 shows the contaminants and their likely pathways. *

*

Figure 6. (above) Pathways and receptors table

Plant uptake Vegetation Soils

*

Ground water

Ground *

Water courses Water

*

Arsenic

*

*

*

Ethylbenzene

*

Inhalation

Xylene

*

* *

Ingestion Demal contact Human Health Benzene

Don

Foundations and remains of buildings could contain contaminants

Gas Holder

The

Potential Sources Potential Pathways Potential Receptors

Potential crops that may be planted could take in contaminants that are in the soil

Wildlife and pets could come into contact with contaminants

Storage tanks contain hazardous liquids and gases, such as the VOC’s, that could contaminate the soils

Bitumen Oxidiser

Lab nal Ca

Pathways and Receptors

Contaminants and risk of them entering path way

5. Pathways and Receptors gs

ildin

l Bu

ntia

ide

use r Ho sal Boile

le

LSC 305 Land Contamination, Restoration, and Revegetation Conceptual Model LSC 305 Land Contamination, Restoration, and Revegetation Conceptual Model

4. Conceptual Model

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Residents could come into contact with contaminants. Inhalation would be the most likely way Train tracks could contain contamination from when they were used for transporting materials

ispo

Trains could transport contaminants to other areas away from the site

8 Tresspssers that pass through the site could be exposed to contaminants through dermal contact, inhalation and possibly ingestion

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Water run-off containing contaminants could be absorbed by soil

dd

D ilt, ste s a nd Wa ,g r a ve l, a Up Alluv nd ial pe de r Ca dep m oli os rb tio it o s n n i rub f ero b u sm i

al

ec o

Water run-off containing contaminants could lead to the canal and River Don and carry to other areas away from the site

Soil could contain contaminants

Conceptual models are used to aid the decision process. They are put in place so techniques can be decided on for the mitigation and remediation plan. It shows clearly the sources, pathways, and contaminants that are on site and can easily be reviewed and updated. 7


LSC 305 Land Contamination, Restoration, and Revegetation

LSC 305 Land Contamination, Restoration, and Revegetation

Mitigation and Remediation

Mitigation and Remediation

6. Mitigation and Remediation

One of the options is through Windrows. These are long piles of contaminated soils. Following excavation they are screened to remove large pieces of concrete and rubble before being laid out on a concrete hardstanding in a series of windrows. The soils will then be mixed periodically using a tractor-drawn windrow turner, with nutrients, fungalenriched composts and other treatment products will then be applied periodically. Tarpaulins are then used to cover the soils. Samples can be taken from each windrow once a week for analysis. When the soils have been remediated they can be removed and reused on site. This technique was carried out on Norwich Riverside where past industrial activities had caused extensive contamination by a range of chemicals including benzene, ethylbenzene, xylenes.

6.1 What is Remediation?

Remediation is the action taken to prevent or minimise, or remedy or mitigate the effects of any identified unacceptable risks. The process must look at reducing or removing the source, blocking or breaking the pathway, and removing the receptor.

6.2 Techniques

There are two possible methods of remediation: -Ex situ- Remove from the sub surface to treat -In Situ- Treat in place There are many remediation techniques that can be effective when correctly applied: Chemical Techniques -In situ chemical oxidation (ISCO) -In situ chemical reduction (ISCR) -Soil stabilisation -Ex situ soil treatment -Ex situ groundwater treatment

Figure 5. (above) Windrows

With it being located alongside a canal and near the River Don it creates a fantastic opportunity to create a park that can be enjoyed by residents of the surrounding area. Vegetation van be planted to absorb the chemicals and clean.

Physical Techniques -Soil separation -Soil washing -Air sparge/vacuum extraction -Dual phase vacuum extraction -Vacuum-enhanced product recovery -Engineered barriers -Ex situ groundwater treatment systems

Centenary Riverside Urban Nature Park in Rotheram was created and provides aesthetic, recreational, health, education and employment benefits to local people. This was created on an old industrial site.

Thermal Techniques -Uses thermally enhanced remediation methods to remove organic contaminants from soils using either direct soil heating, or a variety of heat supplemented extraction techniques. Biological techniques - Many microorganisms that occur naturally in soil and groundwater are able to break down organic contaminants or reduce the toxicity of inorganic contaminants. - Sustainable - Natural processes can be greatly enhanced to achieve controlled and highly effective soil and groundwater remediation.

6.3 Proposed Remediation

Figure 6. (above) Centenary Riverside Urban Nature Park

Time should be taken to ensure this site is fully remediated as the current plan is to build a housing development there. Remediation techniques need to be reliable, cost-effective, acceptable to the Environmental Agency and sufficiently rapid to work withon the time limits set by the development. There are several methods that can be put in place to ensure remediation is carried out effectively.

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LSC 305 Land Contamination, Restoration, and Revegetation

Conclusion

7. Conclusion From the report that has been carried out it shows there will need to be a wide range of expertise from a range of professionals throughout the entire process. These disciplines range from engineers to construction proffesionals. The remediation process must be effective for the site itself. Not one site is the same, so identifying chemicals and locating pathways and receptors is vital. This report does that, providing an overview on the sites contaminates, its sources, pathways, and receptors, as well providing remediation measures which can help remove the chemicals from the site meaning it can have public use in future years.

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Land Contamination Report