Appendix A: Site Appraisal

 

Context of the Site

 

 

A1

The Springfield Mill site is located in the North Esk valley to the west of Polton village. It lies down river from the Roslin Glen Nature Reserve, which is managed by the Scottish Wildlife Trust, and the proposed Roslin Glen Country Park. Hewan Bank Site of Special Scientific Interest (SSSI) lies on the western bank of the North Esk opposite the Site, as does the North Esk Walkway. The Site lies within an Area of Great Landscape Value (AGLV) as identified in the Midlothian Local Plan.

 

 

A2

The Site lies at the start of a 2.5km stretch of the river valley, which is largely inaccessible by vehicles with no public roads or bridging points and little habitation. This section of the valley is densely wooded, with sheer slopes down to the river.

 

 

Historical Background

 

 

A3

Glenesk House and its policies originally occupied the Site with the first paper mill being located within these policies close to the North Esk in 1742. Although Glenesk House is not now in existence, many large specimen trees occur on the Site and date from plantings undertaken in the late 1800’s. The policies of Glenesk House included an ornamental pond and the depression of this is still visible on the Site.

 

 

A4

During the early part of this century, Polton Village was a thriving industrial community with two working paper mills serviced by a railway. Waste material from the mills appears to have been dumped from the late 19th century, on the western part of the Site creating a steep sided mound. This mound is now covered with mature sycamore woodland. The ornamental pond, which formed part of the designed landscape of Glenesk House, was also later used as a reservoir for industry on the Site.

 

 

A5

Springfield Mill ceased production by the late 1960’s and the Site became the property of Lothian Region and Midlothian District Council in 1975. Prior to 1979, the main site offices and two warehouses were used by the District’s Technical Services and Housing Department and the Region’s Highway’s Department used part of the area for an open storage yard. The remainder of the buildings and yards on the mill site (some of which were in private ownership) were occupied by a variety of local businesses up until 1990. A number of derelict buildings were demolished around this time and areas of rubble and hard standing left on the Site.

 

 

Present Use of the Site

 

 

A6

The Site is currently derelict with two buildings remaining; a large former mill and part of a former terrace of stone faced buildings close to the river. The latter building houses an electricity sub-station and is owned by Scottish Power. An electricity connection still exists between the sub-station and the remaining large mill building on the Site. Scottish Power have been consulted with regard to the status of the sub-station and have confirmed (see Appendix A) that the owners of the Site would need to make a request to them to have the power disconnected to the mill, prior to any relocation or removal of the sub-station. A charge may be made by Scottish Power for removal or relocation of the supply, although it is understood that this fee may be waived if the Site were to be used as a wildlife reserve.

 

 

A7

While the Site is no longer used for storage or industry and is effectively ‘derelict’, many local people currently use the area for walking and quiet recreation.

 

 

Landscape Character

 

 

A8

The Site can be split into the following distinct areas of landscape character:

  • A steep sided mound and lower undulating area on the southern part of the Site, colonised by dense woodland, largely compromising sycamore and birch. Woodland on the eastern part of this area is younger than that occurring on the mound, although occasional mature exotic tree and shrub species also occur here. Building footings, walls and dumped materials are readily visible in this eastern undulating area;

  • an area of dense willow/birch sedge and marsh occurring in the large depression of the former ornamental pond of Glenesk House;

  • an open area of large scale derelict buildings, rubble heaps and hard standing colonised in part by pioneer species such as birch, grasses and ruderals;

  • an area of land on the western fringes of the Site and close to the river bank, which appears to have been graded in the past 10 years.

 

 

Nature Conservation Interest

 

 

A9

Phase One and Two Habitat Surveys have been undertaken of the Site and these are available as separate documents, which can be obtained from SMAG.

 

 

A10

The Site is of considerable interest to wildlife. Approximately 4ha of the Site is wooded, making a significant contribution to the Roslin Glen to Bilston Glen semi-natural woodland area. This woodland and regenerating birch, elm and willow scrub provide habitat for nesting songbirds, insects and mammals. Mammals present on the Site include badgers, roe deer, foxes and small rodents. Small pools which exist seasonally within the former pond support a variety of wildlife including frogs, smooth newts and toads, although these are progressively drying out due to natural siltation.

 

 

A11

The derelict part of the Site provides both grassland and ruderal habitats. There is a variety of flora including spotted orchids, mullein, toadflax and a diversity of other plants which provide fodder for many insects among them butterflies such as the red admiral, peacock, small tortoiseshell and rare visitors such as the convolvulus hawk moth and the purple hair streak butterfly. The river walls provide a vantage for the resident kingfishers and the river itself is home to dippers, pied and grey wagtails, brown trout, eels and the plethora of invertebrates which inhabit any such healthy, fast flowing watercourse. Sand martins nesting in Hewan Bank and sparrow hawks also use the Site.

 

 

A12

Bats are present in the large mill building remaining on the Site. The species of bat present is not known and survey would need to be undertaken prior to any detailed mitigation measures being considered in terms of the proposed demolition works and the provision of alternative roosts. Consultation will be undertaken with SNH to clarify the situation with regard to the protection of bats under the Wildlife and Countryside Act 1981. The health and safety aspects associated with the derelict mill building are likely to influence SNH to agree to its demolition providing adequate mitigation measures can be ensured.

 

 

Contamination of the Site

Introduction

 

 

A13

The contamination appraisal of the Site is based on a review of previous site investigation reports, and observations made during a site visit undertaken on 23rd September 1999. No additional soil sampling or analysis of soil, water or other material was undertaken as part of this appraisal.

 

 

A14

Historically, there has been a number of potentially contaminating activities at the Site including the following:

  • A paper works (1742-1966) was located on the northern part of the site and was used to produce paper from rags and later the process changed to produce high grade paper from grass, straw and wood pulp. Potential contaminants may include traces of bleaching agents, pigments and dyes, metals, solvents, chlorinated organic compounds, and oils.

  • A small-scale gas works associated with the mill was present on the northern part of the site (1862 until at least 1918). Potential contaminants may include coal tars and other hydrocarbons, cyanide, spent oxides, ammonia, sulphides, sulphates and heavy metals. In addition, asbestos was also extensively used in insulation materials in gas works in the past.

  • Waste materials presumed to be from the paper works were deposited in a mound initially on the central part of the Site in 1894, extending to the south western area by 1908, and slightly eastwards by 1957. The contaminants arising may include heavy metals, lime, boiler ash, paper pulp and solid gasworks waste (i.e. coal, clinker, ash, lime and spent oxide)

  • Since the mill closure in the 1960s, buildings have been sublet for paint spraying, vehicle repairs and wood stripping and to builders firms, and associated contaminants may include solvents, paints and wood treatment chemicals.

  • An electricity substation is currently located on the northern part of the site, and there is a possibility that polychlorinated biphenyls (PCBs) may have been contained within the transformer unit.

  • Suspected asbestos containing material has been identified in existing stockpiles of demolition rubble. The fabric of the existing buildings may additionally contain asbestos materials.

  • areas of fly-tipped waste, including drums and paint containers, were observed during the site inspection and may cause localised contamination with oils or solvents.

 

 

A15

In relation to the environmental setting of the site, the River North Esk forms the western and northern boundaries of the Site, and is prone to flooding across the low-lying parts of the site. A geological SSSI, Hewan Bank, is adjacent to the northwest of the site, and the nearest residential premises are adjacent to the eastern site boundary.

 

 

Review of previous studies

 

 

A16

Two previous site investigations have been undertaken at the Site and are summarised as follows:

 
 

A17

The Lothian Regional Council undertook an investigation in December 1985 to identify if the former Springfield and Polton mills could be rehabilitated for housing sites. The investigation comprised 6 boreholes and 6 trial pits, all excavated on the central and southern parts of the site, in the vicinity of the pond and the mound of spoil. Nine soil samples were analysed for a range of parameters including pH, moisture, total solids, total alkalinity, ash content, inorganics (sodium, potassium, and sulphate), and metals (lead, cadmium, zinc, aluminium, arsenic and mercury).

  
 

A18

In 1992, WA Fairhurst & Partners undertook a desk study, site inspection and site investigation comprising thirty-two trial pits, two trial trenches and fourteen boreholes. In total, 119 soil and 15 groundwater samples were analysed for a range of parameters. The analysis included pH, calorific value, oxidising agents, inorganics (fluoride, sulphide, sulphite, sulphates, total nitrogen, ammonia, phosphates, cyanides), organics (toluene extractable matter, phenols, formaldehyde) and metals (arsenic, antimony, barium, cadmium, chromium, copper, lead, mercury, nickel and zinc). In addition, three samples of water were taken from the river and two samples from the pond, to assess any impact on surface water quality from leachate/run-off from the site.

  
 

A19

The surveys confirmed the depth of fill varied between 0.3m-3.6m thick within the pond area, up to 15.25m within the mound area, and between 0.3-5.45m thick elsewhere. The fill comprises a clayey sand and gravel that contains lenses of paper waste, wood and other organic debris. In addition ash, coal, blaes, burnt shale, polythene, porcelain, brick, concrete and metal fragments are present within the fill. Alluvial deposits of sand and gravel, with bands of sandy clay underlay the fill. Groundwater appears perched within the fill at depths of between 0.65m – 3.6m bgl. Standing water was also measured at depths of between 1.6m – 14.7m bgl within the natural strata of sand and gravels. Groundwater elevation contour plots indicate groundwater movement is generally towards the river.

  
 

Contaminants in Soil

  
 

A20

In view of the proposed use of the Site as a Wildlife Site, the analytical results from previous site investigations have been assessed against Interdepartmental Committee on the Redevelopment of Contaminated Land (ICRCL) Guidelines for landscaped areas and open space. These are less stringent controls than would be applied to land, which would be developed for housing.

  
 

A21

Overall, soil contamination was not widespread across the site and was restricted to the former gasworks and two areas of buried waste namely in the mound and in land to the south of the former Glenesk house, with contaminants restricted to the fill material.

  
 

Contaminants in Groundwater

  
 

A22

The groundwater at the Site has not been adequately assessed by the previous surveys, with the majority of water samples taken from trial pits for analysis, rather than from properly installed boreholes. In addition oil contamination was visually recorded on trial pit logs at five locations adjacent to the north of the mound. The contamination was described as discoloured black water, with an oily appearance, which could be indicative of leachate from the mound. No analysis for hydrocarbons was undertaken on these water samples.

  
 

A23

The groundwater results have been assessed against the Dutch Intervention guidelines, which although they do not have legal status in the UK, are widely used for assessment purposes. In addition, leachate completion criteria have been used for assessment purposes, given the mound of waste at the Site. The river North Esk flows adjacent to the site and is likely to be in hydraulic continuity with the groundwater from the site. Environmental quality standards (EQS) and surface water classification guidelines have also been used for assessment, and essentially represent ‘clean’ levels. EQS are set for protection of aquatic life from dangerous substances and surface water classification guidelines are set for abstraction of drinking water supply.

 
 

Conclusions

  
 

A24

Based on the findings of the site investigation, there are a number of risks posed by the Site in its current form. Contamination is present within fill materials at the Site and "pollutant linkage" may exist, as defined in the draft guidance on contaminated land. The regulations to implement the provisions of Part IIA of the Environmental Protection Act 1990 will shortly be laid, with the regime entering into force in April 2000. In this regard the following assessment of risks is presented;

  
 

Soil Contaminants

  
 

A25

Chemical analysis results show the soil phase is contaminated with elevated levels of metals (lead, arsenic, barium, antimony, copper, nickel and zinc), toluene extract and sulphate. The contaminants are associated with the ash fill material and are localised on the western part of the site, in the vicinity of the mound, and former gas works site. The soil contaminants are unlikely to pose a risk to future users at the Site, provided the mature vegetation within the mound area is left in situ, which reduces the pathway for exposure, and that the gasworks area, where contamination was detected at shallow depth within the soil profile, has an additional layer of material to cover it.

  
 

Water Contaminants

  
 

A26

The contaminant of greatest concern observed in groundwater was the indication of oily water in several of the trial pits located down gradient of the mound. Hydrocarbons are classed as a List I (black list) dangerous substance. Under section 30F of the Control of Pollution Act 1974, it is an offence to cause or knowingly permit any poisonous, noxious or polluting matter to enter any controlled waters without consent. Under the new Groundwater Regulations 1998, SEPA have powers to issue a notice to prevent or control indirect discharges of hydrocarbons to groundwater. Steps to further assess the hydrocarbon contamination in groundwater are likely to be required by SEPA, and if there is a significant risk of pollution, then clean up of the groundwater may be required.

  
 

A27

Other water contaminants identified at the Site include elevated metals lead, copper and barium which are classed as List II (grey list) substances, and one excessively alkaline sample from within the mound. Risks to the environment associated with the elevated metal contaminants are on water resources and migration of contaminants into the River North Esk, adjacent to the Site. Elevated concentrations of metal in groundwater were measured above Dutch 1 Guideline values and up to ten times above the EQS. These metals can be harmful to the aquatic environment. There is, however, a dilution effect of the contaminants in groundwater upon entering the river. SEPA water quality data downstream which is based on both chemical and biological parameters, does not indicated that any adverse impact on the river has occurred to date, with the water being classed at the top end of A2 (good).

  
 

A28

The remaining water parameters including phenols, sulphates, sulphide, nitrogen and cyanides, were detected at less elevated concentrations and were above EQS or drinking water standards, and are therefore not considered significant.

  
 

Asbestos

  
 

A29

An extract reviewed from the Wimpey Geotechnical survey has identified asbestos to be present in small quantities within demolition spoil at the Site. Asbestos is a known human carcinogen, and the inhalation of airborne asbestos fibres can lead to possible adverse and irreversible carcinogenic health effects. There is no further information provided on the nature of the asbestos found, and thus a full assessment of the risks cannot be made. Currently, there is a requirement for all asbestos to be removed from buildings prior to demolition work. The mill buildings were demolished around ten years ago, and it is likely that under Health and Safety legislation, some form of requirement to remove asbestos in buildings would have been in place at that time.

 
 

Limitations of Previous Site Investigations

  
 

A30

There are a number of limitations to the previous site investigations, which have been undertaken in the past. The principal limitations are the small number of water samples taken and insufficient coverage both in terms of sample locations and analysis. In particular, no assessment of the hydrocarbon contamination of the groundwater has been undertaken and the impact of contamination, if any, on the river has not been addressed.

  
 

A31

In relation to the former gas works area, further work to delineate the hydrocarbon contaminants in this area and determine their nature may be required by SEPA.

  
 

A32

No asbestos analysis has been undertaken on any of the soil samples, and the presence of PCBs in the soil in the vicinity of the electricity substation cannot be discounted. It should be noted that cleaning up of any PCB contamination associated with the substation would be the responsibility of Scottish Power.

  
 

Consultation with SEPA

  
 

A33

Preliminary discussions with SEPA regarding the contamination at the site were held in order to gauge their views on the remedial requirements for the site. SEPA have not reviewed any data on the site and their comments have been based on telephone discussions alone. SEPA’s main concern is with the oil contamination in the groundwater, and they would require further details on the nature and extent of contamination prior to commenting on the remedial options. This would involve additional survey due to the limitations of previous site investigations.

  
 

A34

In relation to the river water quality data supplied by SEPA, the overall water quality is classed as fair upstream and good downstream of the Site. SEPA were not aware of any pollution incidents from the site, however the aesthetic condition (visual observation) for down stream of the Site indicates there are trace list A contaminants, which includes, amongst others, oils. Further survey may also therefore be required to ascertain river quality to SEPA satisfaction.

  
 

Hydrology

  
 

A35

The Site comprises an area of land just under 6 hectares (15 acres) in extent to the immediate west of the village of Polton. It is bounded on its northern and western sides by the River North Esk, which flows in an oxbow form to circle the Site. Levels vary across the site from a peak of just over 92.01m A.O.D. in its south western quadrant to just over 73m A.O.D. along the embankment to the river. The Site comprises one of the few areas of undeveloped level ground within this stretch of the river valley.

  
 

A36

The river flows along the border of the Site discharging over an existing weir at the south western boundary and falls towards and under the Polton Road Bridge, which forms part of the eastern boundary of the Site. Immediately to the east of the bridge there is a further weir which controls the flow of the river in the immediate vicinity of the village.

  
 

A37

To the north of the river, immediately opposite the Site, a steep bank known as Hewan Bank rises steeply (up to approximately 50m in height). The bank comprises a thick layer of sand lying over clay. There is a history of slippage of the bank given its unstable nature, which is vulnerable in times of storm or heavy rain. On 9 December 1979 after prolonged rainfall a huge landslide occurred completely blocking the North Esk with mud rocks and woody material to a depth of 8 metres. The toe of the slide swept across the river into the Mill complex demolishing part of the building used by Midlothian Council. "At this time Hewan Bank was covered in mature trees. In 1980 and again in 1985-86 at great expense a Manpower Services Commission squad cleared these to the damage of their damming the river in future slips. In recent years the bank has continued to slip.

From local information the site flooded again in the early ‘90’s’ but most landslides since the removal of the trees have been small. Large trees are now growing back.

  
 

A38

Recent consultation with SEPA has established that they have assessed that flooding of the subject site occurs at a 1 in 6 year’s frequency, which readily confirms the instability of landform conditions in the locality and the need to monitor the situation.

  
 

Health and Safety Aspects

  
 

General Aspects

  
 

A39

The industrial heritage of the site has left an environment that contains hazards that could cause harm to the public. These hazards arise not only from Victorian industrial activity but also from recent abandonment and neglect and are associated with the following;

 

    • waste and pollution from mill operations;

    • debris arising from historic demolition/clearance which has been spread and covered;

    • debris from recent demolition work in spoil heaps exposed on the surface;

derelict structures and the remains of demolished buildings.

  
 

A40

As the Site currently exists, the owner/occupier owes a duty to the public to guard against known risks. This duty would remain the same with the use of the Site as a wildlife reserve.

  
 

A41

Health and Safety legislation imposes requirements to identify the hazards, carry out risk assessments and to develop proposals, which will eliminate risks where possible, and, where risks cannot be completely eliminated, put in place controls to reduce the residual risk.

  
   

Hazards likely to cause injury comprise:

  • Collapse, slippage or erosions of unstable piles of debris

  • Confined spaces under or between large units or debris

  • Projecting metal bars and other sharp objects

  • Unexpected sudden changes in levels

  • Hidden strewn debris and voids
  
 

A43

Health hazards comprise:

  • Ground contamination

  • Contaminated ground water and standing water after flooding

  • Traces of asbestos in the existing demolition debris

  • Potential harmful products from the decomposition of buried active waste
  
 

A44

Prior to implementing any of the recommended proposals in this Report, the Client is obliged by the Construction (Design and Management) Regulations to appoint a Planning Supervisor to co-ordinate Health and Safety matters during the design, demolition and construction works. This ensures that safety will be considered at each stage of the design and construction process.