Lincolnshire Sand and Gravel Assessment

Minerals and Waste

External Report CR/10/049

iii

BRITISH GEOLOGICAL SURVEY

Minerals and WasteEXTERNAL REPORT CR/10/049

The National Grid and other Ordnance Survey data are used with the permission of the Controller of Her Majesty’s Stationery Office.Licence No: 100017897/ 2010.

KeywordsLincolnshire; sand; gravel; mineral; resource.

National Grid ReferenceSW corner 467000,295000NE corner 555000,422000

Front coverSand and gravel of a River Trent terrace

Bibliographical reference

Linley, K A et al. 2010.Copyright in materials derived from the British Geological Survey’s work is owned by the Natural Environment Research Council (NERC) and/or the authority that commissioned the work. You may not copy or adapt this publication without first obtaining permission. Contact the BGS Intellectual Property Rights Section, British Geological Survey, Keyworth,e-mail ipr@bgs.ac.uk. You may quote extracts of a reasonable length without prior permission, provided a full acknowledgement is given of the source of the extract.Maps and diagrams in this book use topography based on Ordnance Survey mapping.

Lincolnshire Sand and Gravel Assessment

K Linley, A Harrison, A Morigi, J Brayson & J Forster

Contributor/editorJ Mankelow

© NERC 2010. All rights reserved Keyworth, Nottingham British Geological Survey 2010

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ForewordThis report presents the results of a study by the British Geological Survey (BGS) which identified areas of sand and gravel resources in Lincolnshire and, within these resources, identified those potentially suitable for use as aggregate. In addition, information on other features relevant to planning is provided.

AcknowledgementsThe authors would like to thank Jacqueline Hindle and Russell Lawley for their contribution to this report. They would also like to thank the many individuals in the aggregate industry who gave freely of their advice and local knowledge.

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ContentsForeword .......................................................................................................................................vi

Acknowledgements.......................................................................................................................vi

Contents........................................................................................................................................vii

Executive Summary ...................................................................................................................... 1

1 Introduction ............................................................................................................................ 3

2 Project objectives ................................................................................................................... 4

3 Overview of Lincolnshire ...................................................................................................... 5

3.1 Regional overview.......................................................................................................... 5

3.2 Mineral extraction history .............................................................................................. 6

3.3 Sand and gravel resources .............................................................................................. 6

4 Industry consultation (Stage 1) ............................................................................................. 9

4.1 Industry response.......................................................................................................... 10

4.2 Gainsborough................................................................................................................ 11

5 Revision of resource assessment (Stage 2) ......................................................................... 12

6 Revision of resource line work (Stage 3) ............................................................................ 13

6.1 Mineral resource linework (Resource Polygons) ......................................................... 13

6.2 Mineral Assessment Report (MAR) borehole and grading data .................................. 13

6.3 Caveats.......................................................................................................................... 14

6.4 GIS, polygon and attribute table information............................................................... 14

6.5 Non-MAR areas within Lincolnshire ........................................................................... 18

7 Estimated resource volumes (Stage 4)................................................................................ 22

7.1 Volume calculations ..................................................................................................... 22

7.2 Limitations of this approach ......................................................................................... 23

8 Land use impacts on resource volumes (Stage 5) .............................................................. 26

8.1 Mineral Planning Permissions ...................................................................................... 26

8.2 Urban areas ................................................................................................................... 26

8.3 Areas with environmental designations........................................................................ 27

9 Conclusions ........................................................................................................................... 29

Appendix 1 Details of industry survey responses............................................................... 30

Appendix 2 Map outputs ...................................................................................................... 32

Appendix 3 Details of all mineral resource areas identified in study............................... 34

Glossary........................................................................................................................................ 43

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References .................................................................................................................................... 46

Information sources .................................................................................................................... 46

FIGURES

Figure 1: Example of new mineral block based on mineral resource linework and MAR borehole data.......................................................................................................................................... 14

Figure 2: River terrace deposits of the River Slea at Sleaford ...................................................... 19

Figure 3: Variable nature of glaciofluvial deposits near Alford ................................................... 20

Figure 4: Blown sand deposit near Skegness ................................................................................ 20

Figure 5: Potential sub-alluvial deposits at North Kelsey Carrs ................................................... 21

Figure 6: Process for selecting borehole locations which meet BGS/industry criteria ................. 22

Figure 7: Calculation of estimated volume using MAR borehole data......................................... 23

TABLES

Table 1: 2001 census population data (Office of National Statistics)............................................. 5

Table 2: Overburden, thickness and grading values for the different sand and gravel deposits ..... 8

Table 3: MAR criteria and proposed new resource criteria outlined in the questionnaire.............. 9

Table 4: Industry response to proposed new resource criteria ...................................................... 10

Table 5: Scenarios to model as a result of industry consultation .................................................. 11

Table 6: Particle size ..................................................................................................................... 13

Table 7: Grading of resource based on industry feedback and BGS criteria ................................ 15

Table 8: Classification based on area and MAR borehole density ............................................... 16

Table 9: Borehole class criteria for non-MAR boreholes ............................................................. 18

Table 10: Volume and estimated tonnages for grade 1 and 2 resource areas ............................... 25

Table 11: Area of sand and gravel resource after designated areas are removed ......................... 26

Table 12: Areas where mineral sand and gravel resources overlap with environmental designations ............................................................................................................................ 27

Table 13: Volume and estimated tonnages for grade 1 and 2 resource areas minus areas with mineral planning permissions and urban areas....................................................................... 28

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Executive SummaryLincolnshire County Council has identified a need to update and improve its information on sand and gravel resource in the county. The Council commissioned the BGS to undertake an assessment of the county’s resources, the results of which will be used to inform its Minerals and Waste Core Strategy and Development Policies. The output of the assessment was to be encompassed within a written report and Geographical Information System (GIS).

Lincolnshire has sand and gravel resources in fluvial (river), glacial, coastal and wind-blown deposits. During the 1970s the BGS (previously the IGS – Institute of Geological Sciences) carried out extensive sand and gravel resource assessments for much of Lincolnshire and the results were published in a series of Mineral Assessment Reports (MARs).

The principal objective of this project was to reassess the sand and gravel resources identified in the MARs, using the original survey data, interpreting it in the light of modern requirements for aggregates. A second objective was to identify potential resources in areas of the county not covered by the MARs.

The project was carried out in 5 stages:

1. An industry consultation to determine the physical criteria most appropriate for defining sand and gravel resources and to establish if industry had any interest in working resources near Gainsborough.

2. Collation of available data and a revision of the resource assessment in the light of the findings of the industry consultation

3. Construction of a GIS containing information on the geology, composition, particle size, quality (e.g. expressed as Grade 1 and Grade 2, where Grade 1 is the highest rank) and location of sand and gravel resources

4. Use of the GIS to estimate volumes and tonnages of sand and gravel resources5. Employing the GIS to quantify the effects of certain aspects of land use (such as urban areas,

environmental designations, existing permissions) on the sand and gravel resources.

The reassessment of MAR survey data showed that the principal areas containing Grade 1 and 2 resources are: fluvial deposits in the Trent Valley north of Gainsborough; fluvial deposits lying between the Rivers Trent and Witham, to the west of Lincoln; an area of fluvial deposits underlying the floodplain of the River Witham south-east of Lincoln; spreads of river terrace deposits and glaciofluvial deposits around Woodhall Spa; and fluvial deposits around Market Deeping.

The resources around Market Deeping, west of Lincoln and around Woodhall Spa have been, or are currently, worked. The thick and extensive resource that underlie the Witham floodplain southeast of Lincoln have not been exploited, presumably because of they are entirely sub-alluvial and would require wet-working. The sand and gravel resources in the Trent Valley north of Gainsborough are thick, extensive and likely to be of good quality but are not currently worked. The aggregate industry gave a variety of reasons for the apparent lack of interest in this area, including access issues, distance from market, difficulties of working, and adequate reserves elsewhere. Nevertheless, several companies might consider working in the Gainsborough area if the opportunity arose.

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Outside the MAR survey areas the available data proved too sparse and unfavourably distributed to systematically identify and classify sand and gravel resources suitable for aggregates.However, there are indications that resources may exist in fluvial deposits around Sleaford, between Billingborough and Dowsby and near Long Bennington.

The blown sand deposits, which occur extensively north of Market Rasen, have the potential to contain silica sand.

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1 IntroductionLincolnshire County Council is in the process of defining their Minerals and Waste Core Strategy and Development Management Policies. The council has identified a need to update and improve their information on sand and gravel resources within the county to improve the relevance and reliability of the strategy. The then Industrial Mineral Assessment Unit (IMAU) of the BGS conducted a major survey of the principal sand and gravel resource areas in Lincolnshire with the results being presented as Mineral Assessment Reports (MARs) and maps published between 1976 and 1983. This project uses the borehole data and results from this survey along with more recent BGS Mineral Resources line work as a basis from which toprovide revised and updated data and baseline information on the sand and gravel resources of Lincolnshire through an updated interpretation. The data gathered will be used to:

1. Inform the Lincolnshire County Council Minerals and Waste Core Strategy;

2. Improve the quality of sand and gravel information held by the council planning department to aid in their on-going decision making processes.

By identifying and describing the important sand and gravel resources located within Lincolnshire the results from the project will assist Lincolnshire County Council who, under national minerals planning policy, have the responsibility for ensuring there are adequate permitted reserves to meet the requirements of their aggregate apportionment.

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2 Project objectives1. To define digital GIS vector data delineating those areas of Lincolnshire assessed by the

project team as containing sand and gravel resources.

2. To produce a final report (one hardcopy version and one version in Adobe PDF format to Lincolnshire County Council), which explains the project methodology and results and describes relevant geology of Lincolnshire.

3. To carry out objectives 1 and 2 in a manner which provides an evidence base for the Lincolnshire Core Strategy and informs their area of search selection

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3 Overview of Lincolnshire 3.1 REGIONAL OVERVIEWLincolnshire covers an area of 5,915 km2, making it one of the larger English counties. It encompasses seven unitary authorities – Lincoln, Boston, South Holland, North and South Kesteven and East and West Lindsey. The region shares common boundaries with five other English regions: Humberside, Nottinghamshire, Leicestershire, Cambridgeshire and Norfolk. 1.1% of UK population live within Lincolnshire, with East Lindsey Unitary authority having the largest percentage of Lincolnshire residents (Table 1).

Table 1: 2001 census population data (Office of National Statistics)

Area 2001 Population

UK 58 789 194

England 49 138 831

Lincolnshire 646 645 (1.1% of UK, 1.3% of England)

Lincoln 85 616 (13.2% of Lincolnshire)

Boston 55 739 (8.6% of Lincolnshire)

South Holland 76 512 (11.8% of Lincolnshire)

North Kesteven 94 024 (14.5% of Lincolnshire)

South Kesteven 124 788 (19.3% of Lincolnshire)

East Lindsey 130 455 (20.2% of Lincolnshire)

West Lindsey 79 512 (12.3% of Lincolnshire)

Much of Lincolnshire is rural. The Lincolnshire Wolds Area of Outstanding Natural Beauty (AONB) lies within the north east of the county, running roughly parallel with the North Sea coast, covering an area of 558 km2. The Wolds are made up of a series of steep valleys and low hills, underlain by chalk, limestone and sandstone, laid down during the Cretaceous period.

The A1 runs north south along the westerly edge of the county, becoming the A1(M) outside of the county. There are no motorways within Lincolnshire, but numerous A roads cross through the county, connecting the main towns.

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3.2 MINERAL EXTRACTION HISTORYLincolnshire has significant deposits of a variety of important mineral resources. These include sand and gravel, clay, peat and bedrock such as chalk and limestone. Mineral can only be extracted where it exists, thus a good understanding of the regional geology is important.

Sand and gravel is the most important of the County’s aggregate minerals. Deposits can be foundacross the county, but the most significant deposits, and thus the highest densities of workings, are in the Trent Valley (south-west of Lincoln), the Lower Bain Valley and the Baston Langtoft-West Deeping area in the south of the county (Lincolnshire County Council, 1991).

3.3 SAND AND GRAVEL RESOURCES Sand and gravel are defined on the basis of particle size as opposed to composition. Currently the term ‘gravel’ is used to describe material coarser than 4mm, with a maximum size of 40mm. ‘Sand’ is described as material that is finer, but coarser than 0.063mm. Material with a particle size of less than 0.063mm is classed as ‘fines’.

The superficial or ‘drift’ sand and gravel deposits accumulated in a variety of geological environments but are broadly divided into

� Alluvium

� River terrace deposits (including sub-alluvium)

� Glaciofluvial deposits

� Blown sand

� Beach deposits

3.3.1 AlluviumAlluvium has been transported by a river or stream and been deposited within the river floodplain. It is clastic, detrital material, with a composition reflecting that of the sediment transported by the river system, controlled by the geology of the catchment from where it originated. The grain size of the deposit can vary within the floodplain, controlled by water speed at time of deposition. It is principally composed of clay and silt, sometimes containing lenses of peat and commonly with a thin basal sand and gravel. The generally thin deposit, up to approximately 3m in thickness, can often cover large areas. Alluvium along the River Witham, southeast of Lincoln and northeast of Sleaford, is up to 5km wide in places. Alluvium often overlies older river terrace deposits, sediments laid down previously by the river system.

3.3.2 River terrace depositsIn Lincolnshire, the river terrace deposits are best developed along the River Witham, River Trent and River Welland within the MAR assessed areas. Outside of the MAR assessed areas, river terrace deposits are also present along the River Slea.

Resources of river sand and gravel take the form of extensive spreads of sand and gravel that occur in both raised river terrace sequences flanking the modern floodplains and in flood plain terraces associated with, and underlying, present day alluvium. River sand and gravel resources are reasonably consistent over considerable distances, their composition reflecting, in general, the geology of the river catchment from which they were reworked. Generally, they are ‘clean’ deposits, with low fines content.

Overall, based on the MAR data for boreholes located within the delineated river terrace deposit mineral blocks, the deposit has a mean thickness of 4.8m, with a maximum and minimum of 10.4m and 0.3m respectively. As stated above, it is a relatively clean deposit with low average fines content. The mean sand content of the deposit is 63.5% and for gravel it is 31.1%.

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Overburden is generally thin, up to 6.8m with an average of 1.7m (Table 2). Of particular note is that for the large expanse of River Witham terraces in the centre of the region the overburden is thinnest in the northwest, near Lincoln, and thickens south-eastwards.

The composition of the river terrace deposits varies. Typically, the gravel fraction in River Trent terrace deposits contains brown and purple quartzites, probably derived from Permo-Triassic and Carboniferous formations, and vein quartz. Flint, chert, and red and brown sandstone are also present. It is recorded in MAR 19 that the sand fraction typically consists of sub rounded to well rounded quartz grain. It has also been recorded in the MARs that the river terrace deposits for the River Trent contain occasional coal specks, and those of the River Witham and Welland contain occasional small amounts of chalk.

As detailed in MAR 94 and MAR 100, the River Witham river terrace deposits are divisible into two units. The upper unit consist of flint, limestone, quartzite and quartz. The lower unit is more uniform, consisting of quartzite and vein quartz, with flint and limestone. The sand fraction typically consists of quartz, feldspar and haematite. According to MAR 94, within the River Witham deposits the proportion of ‘fines’ is lowest in the south near Coningsby but increases northwards.

Generally, only exposed river terraces are depicted on the 1:50,000 geological maps, although inferred resources in sub-alluvial sand and gravel deposits occurring beneath river floodplains may be extensive in some places, and have been identified in the Mineral Resources linework utilised within this project. When they are underlying alluvium, as with much of the River Witham east of Lincoln, these deposits will be water saturated and require wet-working,potentially making them less desirable as a resource.

3.3.3 Glaciofluvial depositsLincolnshire has been affected by at least two glaciations, probably three, although evidence of earlier phases has largely been obliterated by the final, Devensian phase. Glaciofluvial deposits are the products of deposition by the associated glacial meltwaters. Bodies of sand and gravel may occur as sporadic irregular lenses within and/or above the till (boulder clay) sequence. Areas of wholly concealed, and thus unknown, bodies of sand and gravel may occur under spreads of till and other superficial deposits.

Resources identified within the glaciofluvial deposits are most extensive east of the River Trent in the north of the region, and to the east of the River Witham, north of Boston.

Based on the MAR data for boreholes located within the identified Glaciofluvial mineral blocks, the deposit has a mean thickness of 4.3m, with a maximum and minimum of 9.6m and 1.6m respectively. The mean sand content of the deposit is 73.6% and for gravel it is 19.3% (Table 2). As is typical of glaciofluvial deposits, there are large variations in thickness and composition, with generally slightly higher fines content in comparison to river terrace deposits. Overburden is generally thin, up to 3.6m with an average of 0.7m.

3.3.4 Blown sandThese deposits, mostly located to the northeast of Gainsborough, close to the northern county boundary, are generally composed of fine-grained sand with a mean fines content of around 10per cent. The sand comprises sub-rounded to well rounded quartz grains. These deposits are believed to be largely of late Quaternary age resulting from aeolian reworking of fluvial and glaciofluvial sands. Blown sand has accumulated mainly along the lower slopes of major west-facing escarpments. Appreciable thickness variations occur across short distances in these deposits due to their undulating topography. Blown Sand deposits are typically worked as a source of silica sand and for mortar sand production.

Based on the MAR data for boreholes located within the delineated blown sand mineral blocks, the deposit has a mean thickness of 2.7m, with a maximum and minimum of 4.6m and 2m

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respectively. As expected for a deposit transported by aeolian processes, the mean sand content of the deposit is 89.8% with a low average gravel content of 1%. Overburden is generally thin, averaging only 0.3m (Table 2).

3.3.5 Beach depositsIncluded in this category are deposits shown on BGS geological maps as 'Shoreface and Beach Deposits', 'Storm Beach Deposits' and a variety of other beach deposits. Typically they occur as accumulations of sand and gravel restricted to the modern coast and a relatively narrow belt of country adjacent to it. In Lincolnshire, however, with its long history of coastal changes and migrations, deposits also occur up to 6 km inland from the present coastline, such as the storm beach deposit located between Skegness and Boston.

Table 2: Overburden, thickness and grading values for the different sand and graveldeposits

DepositOverburden Resource Thickness Resource Grading

Min Max Mean Min Max Mean Sand mean %

Gravel mean %

River terrace deposit 0 6.8 1.7 0.3 10.4 4.8 63.5 31.1

Glaciofluvial 0 3.6 0.7 1.6 9.6 4.3 73.6 19.3

Blown sand 0 0.5 0.3 2 4.6 2.7 89.8 1.0

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4 Industry consultation (Stage 1)Consultation with industry was undertaken to ascertain current physical criteria for extractionspecifically overburden to mineral ratios, deposit thicknesses and fines content. Industry was invited to review and comment upon BGS suggested criteria. Consultation also took place with industry on preferred zones within the county for extraction, such as near Gainsborough, and to ascertain reasons why some areas identified as containing sand and gravel resources are not currently worked. It has been noted that certain areas within the county have been less targeted by the minerals industry for extraction than other areas. Industry were asked if there are specific reasons for this and to report any results that may affect future supply.

Lincolnshire County Council supplied details for 34 aggregate contacts. Eight of these were relevant for consultation during this report, six were active sand and gravel operators and two were trade organisations.

All eight relevant contacts were telephoned initially, and emailed a short questionnaire containing the original Mineral Assessment Report (MAR) criteria and the proposed new criteria, (Table 3), and the question regarding the Gainsborough area given in section 4.2. Sevenresponses were received.

Table 3: MAR criteria and proposed new resource criteria outlined in the questionnaire

Original MAR Criteria New Criteria

The deposit should average at least 1 m in thickness.

The deposit should average at least 2m thickness.

Ratio of overburden to sand and gravel should be no more than 3:1.

Ratio of overburden to mineral should not exceed 1:1.

The proportion of fines (particles passing 0.063 mm B.S. sieve) should not exceed 40per cent.

The proportion of fines (particles passing 0.063 mm B.S. sieve) should not exceed 40 per cent.

The base of the deposit should lie within 25 m of the surface, this being taken as the likely maximum working depth under most circumstances.

It follows from the second criterion that boreholes are drilled no deeper than 18 m if no sand and gravel has been proved.

The deposit should lie within 5-10 m of the surface.

The new criteria were first introduced in a sand and gravel review for Yorkshire and the Humber (McEvoy et al., 2004), and were based on information provided by the Mineral Products Association (formerly the Quarry Products Association).

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4.1 INDUSTRY RESPONSETable 4 summarises the feedback from industry. A more detailed summary of the feedback is available in Appendix 1. The results were varied with a range of views.

Table 4: Industry response to proposed new resource criteria

Proposed Criteria Agree Disagree Suggestions

The deposit should average >2m thickness.

5 2No other criteria

suggested.

Ratio of overburden to mineral should not exceed 1:1.

3 4 2:1(2 responses)

3:1(2 responses)

The proportion of fines should not exceed 40 per cent.

2 5 30% 15-20% 15% Sand 70%, Silt 20%

The deposit should lie within 5-10 m of the surface.

6 1 5 metres max (1 response)

Most respondents agreed that to be geologically viable resources should lie within 10 m of the surface but opinions differed on the other criteria. When the responses were analysed it became apparent that nine different sets of criteria would be required to satisfy all possible scenarios (Table 5).

It was beyond the scope of this project to provide information on all nine possible scenarios, therefore three were selected that satisfy the requirements of the majority of respondents. Of these, the outcome of applying one (Overburden/Mineral <3:1; Fines <40%) is already available in published MARs. The other two, highlighted in bold in Table 5, are believed to be the most useful sets of criteria for defining potential sand and gravel resources in Lincolnshire and are the ones adopted for this research. They represent the best case scenario (overburden/mineral ratio <1:1, less than 15% fines, deposit within 10 metres of the surface and at least 2 metres thick), classified as Grade 1 for this report, and a ‘middle’ scenario (overburden/mineral <2:1, less than 30% fines, deposit within 10 metres of the surface and at least 2 metres thickness) classified as Grade 2 for this report.

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Table 5: Scenarios to model as a result of industry consultation

RatioDeposit within 10mof surface and atleast 2m in thickness

Overburden

1:1 2:1 3:1

Percentage of fines

<15%Overburden 1:1Fines < 15%

Overburden 2:1

Fines < 15%

Overburden 3:1

Fines < 15%

<30%Overburden 1:1

Fines < 30%Overburden 2:1Fines < 30%

Overburden 3:1

Fines < 30%

<40%Overburden 1:1

Fines < 40%

Overburden 2:1

Fines < 40%Overburden 3:1

Fines < 40% *

* Criteria used in the published BGS Mineral Assessment Reports

4.2 GAINSBOROUGH The industry consultation included the following questions regarding sand and gravel resources in the Gainsborough area, in the North West of the county.

� Has your organisation considered working in this area?

� If yes, what are the main reasons you do not work this area?

� Would you consider working this area in the future?Only 3 of the 7 respondents commented on the potential of the Gainsborough area.

Industry considers that although the river valley around Gainsborough is underlain by high quality sand and gravel, the overburden here includes a considerable thickness of peat. Due to the difficulties of handling this material, which is nearly liquid and has a low angle of repose, the resource area is viewed as offering very limited restoration and afteruse options.

Research into working in the Gainsborough area, access issues, its distance from major markets (Lincoln and Sheffield), lack of opportunity and/or competition and existing permitted reserves in the south, has led to industry not actively promoting the area at present.

Sites that have been investigated by industry in the past include Lea Marsh, on the adjacent side of the River Trent to the Sturton le Steeple site within Nottinghamshire, identified in the Nottinghamshire Minerals Local Plan as M6.8 (Nottinghamshire County Council, 2005), and Misson, near Bawtry.

Industry stated that they would, however, consider any newly identified sites around Gainsborough, should suitable resources be identified.

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5 Revision of resource assessment (Stage 2)The revised assessment of sand and gravel resources in the County encompassed the following main tasks:

� Compilation of existing BGS data and information including Mineral Resources data and MAR data.

� Re-interpretation of MAR borehole data to reflect current geological conditions required to make the working of sand and gravel economic.

N.B. This assessment does not take into account other requirements such as resource demand, distance from main roads, access etc.

� Redefinition of resource blocks and quality ratings using new information, including that derived from the consultation and re-interpreted borehole data, as outlined in section 4.1and summarised in Table 7.

� Incorporation of new geological information and borehole data as appropriate, particularly outside the MAR study areas, such as the discovery of pre-glacial fluvial deposits in southern Lincolnshire, and the attribution of resource information to this geological data.

The identification and delineation of mineral resources is inevitably somewhat imprecise. It is limited not only by the quantity and quality of data currently available, but also involves predicting what might, or might not, become economic to work in the future. The assessment of mineral resources is, therefore, a dynamic process, which must take into account a range of factors. These include geological reinterpretation as additional data becomes available. For this work three categories of mineral resource line work were utilised reflecting differing degrees of geological assurance: unproven, inferred and indicated, explained as follows:

Indicated resources: are those in which there is a greater degree of geological assurance and the tonnage and grade are computed partially from specific measurements, in this case borehole data. Indicated resources only occur in areas assessed for sand and gravel by BGS resource surveys (MARs) which defined them by overburden to mineral ratios, fines content, thickness and depth. In these areas, the possible extent of sand and gravel concealed beneath till (boulder clay) and/ or other material is shown.

Inferred resources: are those defined from available geological information. They have been evaluated by drilling or other sampling methods, but drilling density is inadequate to allow a more detailed assessment.

Unproven resources: are those defined on a geological map but for which no borehole or sampling information is available. For details of borehole density requirements, see Table 8.

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6 Revision of resource line work (Stage 3)This section describes the methodology employed in reassessing and redefining the potential sand and gravel resources of the County. Two methodologies were employed: one for areas covered by the MAR reports (Information Sources section) and a second for areas not covered by the MAR reports. These two different methodologies are described below.

6.1 MINERAL RESOURCE LINEWORK (RESOURCE POLYGONS)The mineral resource linework (Harrison et al., 2002) is largely derived from the BGS Digital Geological Map of Great Britain at the 1:50 000 scale (DiGMapGB-50). Where sand and gravel assessment studies have been undertaken by the British Geological Survey or other organisations, sufficient information may be available to define mineral resources at the indicated resource level. The mineral resource linework is also based on digitised 1:25 000 scale mineral assessment maps, where these are available. The MAR areas are shown in Appendix 2.1, MAR borehole locations are shown in Appendix 2.2 and the mineral resource linework is shown in Appendix 2.3, these form the focus of the analysis carried out.

The redefinition of the resource polygons is based around the MAR data and new polygons were derived using a combination of the original BGS mineral resources linework, the information from the distribution and content of the MAR boreholes and expert geological knowledge.

6.2 MINERAL ASSESSMENT REPORT (MAR) BOREHOLE AND GRADING DATAThe data collected within the MAR areas describes the boreholes in terms of the geological classification and lithology. The combination of these two attributes enables the classification of overburden, mineral resource and waste. The borehole data were used to estimate of the depth of each, to calculate the overburden to resource ratio and provide an approximate thickness for each layer. Thickness, in combination with the areal extent of the resource was used to determine an approximate volume. It should be noted that the resource identified may not be a continuous layer, in some boreholes it may be interspersed with horizons of waste i.e. non mineral.

The grading data reflect the type of material found within each horizon based on particle size as shown in Table 6. A combination of these two datasets has been used to identify likely areas of mineral resource and estimates of volumes of material have been made based on this data. The grading data reflects the percentage of the sample retained by a series of sieves of standard mesh sizes. This information allows the delimitation of broad gavel, sand and fines categories based on particle size. This data is represented as a percentage of the whole sample.

Table 6: Particle size

Particle Size (mm) Classification

4 - 64 Gravel

0.0630 - 4 Sand

<0.0630 Fines

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6.3 CAVEATSIt should be noted that there may be spatial variation in the distribution of the MAR borehole data and this should be taken into consideration when evaluating the results based on this information.

In combining information from the mineral resource areas and the MAR borehole geology and grading information it should also be recognised that the results will be subjective and, therefore, only be used as guideline figures.

Identification of waste material within each borehole is subjective and relies on the classification applied by the original field geologist. This is an area where inconsistency may have occurred and it contributes to the understanding that any volume and tonnage calculations which are based on the MAR borehole information should at no stage be considered as anything more than an imprecise but useful indication.

6.4 GIS, POLYGON AND ATTRIBUTE TABLE INFORMATIONThe GIS software (ArcGIS 9.2) enables the combining and analysis of the mineral resource linework and the detailed borehole and grading data.

New mineral blocks (‘resource polygons’) were drawn, based on a reinterpretation of these datasets, as shown in Appendix 2.4. The BGS Mineral Resource linework was used as a starting point and was updated to accommodate the reinterpretation of the borehole data (Figure 1). The original mineral resources linework has been retained unless MAR borehole data suggestedchanges were required.

Figure 1: Example of new mineral block based on mineral resource linework and MAR borehole data

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BGS © NERC. All rights reserved.

By this means each of the resource polygons was attributed with the set of values and/or descriptors, listed in Section 6.4.1 to 6.4.14.

Due to the new resource linework originating from the mineral resources linework, a small number of polygons within the MAR area, overflow into the non-MAR area. This is due to MAR boreholes providing information for the resource, but due the polygon following geologicallinework and not being controlled by the report area, it continues through the boundary of the MAR assessed area (e.g. Polygon 124 in the centre of Lincolnshire).

Each polygon has been attributed with all (MAR) or some (non-MAR) of the attributes listed below. These values can be viewed in the associated GIS attribute table, and many of the attributes are listed in the table in Appendix 3. The name in brackets is the name displayed in the GIS attribute table.

6.4.1 ID (ID)A unique identifier was given to each polygon area in the form of a numerical ID. A complete table of the areas and results are shown in Appendix 2.5 and Appendix 3.

6.4.2 Number of Boreholes (NoBorehole)In calculating the volumes of resource within a resource area the MAR boreholes within the area where identified and the information associated with them analysed to calculate the estimated volumes. This value in the GIS attribute table, and in Appendix 3, indicates the number of boreholes which lie within each resource polygon. The number of boreholes was also used to assign a ‘class’ to the resource polygon (see Table 8)

6.4.3 Grade (Grade)The resources were assigned to a resource Grade, based on feedback from industry as described in Section 4.1 and shown in Table 7.

Table 7: Grading of resource based on industry feedback and BGS criteria

Resource Grade Criteria

Grade 1

1:1 overburden to mineral ratioLess than 15% finesAt least 2m depth of resourceWithin 10m of surface

Grade 2

2:1 overburden to mineral ratioLess than 30% finesAt least 2m depth of resourceWithin 10m of surface

Not gradedMineral resources linework indicate the presence of resource but no supplementary borehole data is available to validate this.

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6.4.4 Class (Class)Each resource polygon was assessed and where information existed it was classified into one of the classes shown in Table 8.

Table 8: Classification based on area and MAR borehole density

Class Criteria

IndicatedPolygon has an area of greater than 2km2 and contains at least 5 (evenly spaced) MAR boreholes. Based on the statistical procedure utilised in the MAR assessments (Appendix 2 is all MAR reports).

Inferred with Polygon has an area of less than 2km2 or contains less than 5 (evenly spaced) MAR boreholes

Unproven A Mineral Resources polygon within the MAR area, with no MAR boreholes associated with it.

The grade and class were combined together to give the five unique classes:

(i) Grade 1 Indicated

Identified as the best areas of resource based on mineral resource linework, borehole information and expert geological knowledge, meeting the criteria shown Table 3.

(ii) Grade 1 Inferred with borehole data

Identified as the best areas of resource based on mineral resource linework and expert knowledge, meeting the criteria shown in Table 3 but lack density and distribution of boreholes to confirm the assessment.

(iii) Grade 2 Indicated

Identified as areas of resource based on mineral resource linework, borehole information and expert geological knowledge, meeting lower level criteria shown inTable 3.

(iv) Grade 2 Inferred with borehole data

Identified as areas of resource based on mineral resource linework and expert geological knowledge, meeting lower level criteria shown in Table 3, but lackingdensity and distribution of boreholes to confirm the assessment.

(v) Unproven deposit

Areas identified as resource based on geological linework but lacking further information.

6.4.5 Geology (Geology)The geological deposit identified within the resource polygon describes the geological origin of the deposit using the following classification:

(i) Alluvium (overlying river terrace deposits)

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(ii) River terrace deposits

(iii) Glaciofluvial deposits

(iv) Blown sand

(v) Beach deposits

6.4.6 Geological notes (NBGeology)Composition information extracted from the “Composition of the Sand and Gravel Deposits” section of the MAR report for the area. If further information was required, the relevant MAR boreholes were consulted for refinement. Information was only given for deleterious material (specifically chalk, coal and Mercia Mudstone). This information is shown in the results tables (Table 10 and Appendix 3) where it is identified as Borehole Geology Notes.

6.4.7 Mean Overburden (MeanOB)The mean overburden was calculated by identifying all MAR boreholes within an individual resource polygon. Within each borehole the top and base depth values were identified and used to calculate the thickness of overburden in metres. The thicknesses for all boreholes in the selected resource area were used to create an average overburden thickness.

6.4.8 Mean Resource (MeanRes)This is the mean thickness in metres of resource in an individual polygon calculated from averaging the thicknesses proved in all MAR boreholes within the polygon. For each borehole the top and base depth values were identified and used to calculate the thickness of resource (as shown in Appendix 2.6).

It should, however, be noted that there is not necessarily a continuous resource in every borehole. In some boreholes poorer quality, non-resource (waste) material may intervene between layers of resource. The thickness of resource simply indicates the total thickness of resource in a given borehole.

6.4.9 Mean Fines % (MeanFine)As described in Table 6 the Fines are material of less than 0.063 mm in diameter (that is, clay and silt) and are shown as a percentage value for each sample.

The mean value was calculated by creating an average fines value for potential resource within each borehole, based on the number of grading samples analysed in the original data collection. Generally, sampling was at 1m intervals down the borehole where material was identified as having resource potential.

The mean values for all boreholes within an individual resource polygon were then averaged to provide a mean fines content for the polygon.

6.4.10 Mean Sand % (MeanSand)The sand grading information represents the material which passes through the 4mm grading sieve but is retained by the 0.063mm sieve during particle size analysis (Table 6). The value is shown as a percentage value for each sample.

The mean value was calculated by creating an average sand value for potential resource within each borehole, based on the number of grading samples analysed in the original data collection. Generally, sampling was at 1m intervals down the borehole where material was identified as having resource potential.

The mean values for all boreholes within an individual resource polygon were then averaged to provide a mean sand content for the polygon.

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6.4.11 Mean Gravel % (MeanGrav)The gravel grading information represents the material which passes through the 64mm grading sieve but is retained by the 4mm sieve during particle size analysis (Table 6).

The mean value was calculated by creating an average gravel value for potential resource within each borehole, based on the number of grading samples analysed in the original data collection. Generally, sampling was at 1m intervals down the borehole where material was identified as having resource potential.

The mean values for all boreholes within an individual resource polygon were then averaged to provide a mean gravel content for the polygon.

6.4.12 Area (AreaHa)The area of each resource polygon in hectares.

6.4.13 Volume (VolM3)Volumes were calculated, in cubic metres, from the product of mean thickness and area. Further details and an example of this calculation are given in Section 7.1.

6.4.14 Tonnage (Tonnage)Tonnage was calculated by applying an approximate density of 1.65 for sand and gravel to the estimated volume. Further details of this calculation are given in Section 7.1.

6.5 NON-MAR AREAS WITHIN LINCOLNSHIREWithin Lincolnshire there are many areas of sand and gravel resource identified on the BGS Mineral Resource maps that were not investigated as part of the MAR surveys. Non-MAR boreholes were assessed to provide a generalised picture of the potential of these deposits.

6.5.1 MethodologyThe mineral resource polygons within Lincolnshire but falling outside MAR areas were identified. BGS borehole records located within these mineral resource polygons were then selected for assessment (Appendix 2.7 and Appendix 2.8). There were 1401 such boreholes found and they were classified based on the following criteria:

Table 9: Borehole class criteria for non-MAR boreholes

Class Criteria

A Has resource of 2 or more metres thickness within 10 metres of the ground surface; overburden/resource ratio of 1:1 or better.

B Has resource of 2 or more metres thickness within 10 metres of the ground surface; overburden/resource ratio of between 2:1 and 1:1.

C No resource within 10 metres of the ground surface.

D Has some information but not adequate to suggest or rule out resource present.

E Has no information

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These criteria are based upon feedback from industry consultation as discussed in Section 4.However, due to the nature of the information contained within the borehole logs assessed, it is not possible to comment on the quality (grading and composition) of any potential resource. This assessment is designed solely to give an indication of areas suitable for further investigation.

6.5.2 InterpretationThe boreholes rated as A, B and C are displayed in Appendix 2.7. It is important to note that the interpretation of these boreholes is limited by their spatial distribution and density; the rating given is based on very basic data and is in no way comparable to the MAR borehole data.

River Terrace Deposits:Boreholes suggest that many of the river terrace deposits in Lincolnshire could be sand and gravel resources; examples can be found at Sleaford (Figure 2), Billingborough and north of Long Bennington.

Figure 2: River terrace deposits of the River Slea at Sleaford

However, not all river terrace deposits are shown to have sand and gravel resource, for example north of Bourne and close to Grantham.

Glaciofluvial deposits:The nature of Glaciofluvial deposits means that they are likely to be variable; this is reflected in the boreholes assessed, as can be seen at Alford (Figure 3) and Keelby:

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Figure 3: Variable nature of glaciofluvial deposits near Alford

Figure 4: Blown sand deposit near Skegness

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Glaciofluvial deposits at Toot Hill appear to contain good sand and gravel resource but it is expected that this resource would vary over its extent and therefore these results should be treated with caution.

Blown Sand:The main area of blown sand outside of the MAR areas occurs in the north of Lincolnshire spanning a large area from Market Rasen north to Grasby. The number of boreholes in this polygon is low and their distribution unfavourable to allow any degree of certainty. Nevertheless, they do suggest that this deposit would be a resource.

A strip of blown sand also occurs along the coast at Skegness: boreholes in the northern part of this deposit suggest that this is a resource (Figure 4).

Sub-alluvial gravel and sand:Alluvium is included in mineral resource maps because of the possible presence of sub-alluvial gravels and sands; examples of this can be found at Hemingby, Bishopbridge and North Kelsey Carrs (Figure 5).

Figure 5: Potential sub-alluvial deposits at North Kelsey Carrs

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7 Estimated resource volumes (Stage 4)During the Mineral Assessment Report data collection, 631 boreholes were drilled within Lincolnshire and associated data was collected. Of these boreholes grading data was compiled for 624. On examination of the other seven boreholes they were found to contain only overburden in the top 10m, these areas were therefore identified as unproven deposits.

Each borehole was evaluated against the criteria shown below. If it failed to meet any criteria it did not qualify for the next stage of the evaluation. This iterative data processing allowed the identification of locations which meet the criteria defined in Section 4.

Figure 6: Process for selecting borehole locations which meet BGS/industry criteria

7.1 VOLUME CALCULATIONSThe average thickness of resource, in metres (described in Section 6.4.8) based on the individual borehole data within each polygon area was used to generate an average resource thickness within each mineral polygon area (as defined by the geologist).

These average resource thickness values were multiplied by the area of the polygon (calculated in square metres) to provide an approximate volume within each polygon area.

An example of this calculation is shown in Figure 7.

10m depth or less

Overburden < 5m

Resource > 2m

Ratio of Overburden to Resource 1:1 or 2:1

Percentage Fines <15% or 15 to 30%

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Figure 7: Calculation of estimated volume using MAR borehole dataBGS © NERC. All rights reserved.

Having determined the approximate volume within each polygon in cubic metres a factor of 1.65 (approximate density) was used to convert these values into approximate tonnages. These are given in Table 10 and Table 13. Extreme caution should be applied when using these values as they are only seen as guideline figures.

7.2 LIMITATIONS OF THIS APPROACHThe general limitations of this approach are that identification and delineation of mineral resources are inevitably imprecise and are limited by the quality and quantity of data currently available.

Specific limitations are:

� The extent of exposed sand and gravel deposits is more accurately known than concealed deposits because the former have been observed and mapped by a geologist whereas the latter is known only from widely distributed boreholes.

� The properties of a resource are only known with a degree of certainty in the immediate vicinity of a borehole.

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� Delineation of the resource polygons involved interpolation between widely spaced borehole data and a significant element of expert interpretation by a geologist.

� Whilst the calculation of the areas of individual resource polygons is relatively accurate the estimates of volume should be treated with caution. This is because assumptions were made about the 3D geometry of the resource (e.g. it occurs in tabular bodies and topography is not a significant factor) and the continuity of the resource between data points, and the calculations themselves were fairly simplistic.

� The conversion from volume to tonnes uses an approximate factor that represents the unprocessed density of the resource and does not take into consideration variations in particle size and composition or whether the resource is wet or dry. The estimates of tonnage should, therefore, be treated with caution.

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/10/

049

25

Tab

le 1

0: V

olum

e an

d es

timat

ed to

nnag

es fo

r gr

ade

1 an

d 2

reso

urce

are

as

ID

Gra

de

Geo

logy

Bo

reho

le G

eolo

gy N

otes

M

ean

Ove

rbur

den

thic

knes

s (m

)

Mea

n Re

sour

ce

thic

knes

s (m

) M

ean

Fine

%

M

ean

Sand

G

radi

ng %

M

ean

Gra

vel

Gra

ding

%

Are

a (h

a)

Esti

mat

ed

Vol

ume

(m3 )

Esti

mat

ed

Tonn

age

1 1

Rive

r ter

race

O

ccas

iona

l cha

lk

1.1

3.4

4.7

50.2

45

.1

6 95

9 23

4 52

1 10

0 38

7 00

0 00

0

2 1

Rive

r ter

race

N

A

0.5

5.5

5.6

54.8

39

.6

6 50

3 35

5 06

3 80

0 58

5 90

0 00

0

3 1

Rive

r ter

race

N

A

0.6

5.3

4.1

79.7

16

.2

808

42 5

81 6

00

70 3

00 0

00

4 1

Rive

r ter

race

O

ccas

iona

l coa

l spe

cks

0.7

7.0

4.1

94.2

1.

7 2

937

206

764

800

341

100

000

7 1

Allu

vium

ove

rlyi

ng

rive

r ter

race

N

A

2.8

6.1

3.6

66.4

30

.0

6 84

5 42

0 28

3 00

0 69

3 50

0 00

0

8 1

Gla

ciof

luvi

al

Loca

lised

cha

lk

0.6

6.0

4.9

84.0

11

.1

1 12

0 66

976

000

11

0 50

0 00

0

9 1

Gla

ciof

luvi

al

Loca

lised

cha

lk

1.0

4.9

5.7

71.5

22

.8

1 64

2 79

801

200

13

1 70

0 00

0

15

1 A

lluvi

um o

verl

ying

ri

ver t

erra

ce

Chal

k in

riv

er te

rrac

e de

posi

t 3.

1 6.

1 4.

4 75

.2

20.4

1

876

114

436

000

188

800

000

21

1 A

lluvi

um o

verl

ying

ri

ver t

erra

ce

NA

1.

2 5.

9 7.

1 65

.2

27.7

39

1 22

990

800

38

000

000

59

1 Bl

own

sand

N

A

0.2

2.7

5.8

93.9

0.

3 81

3 22

276

200

36

800

000

5 2

Rive

r ter

race

N

A

0.8

3.0

21.0

65

.0

14.0

74

9 22

470

000

37

100

000

37

2 A

lluvi

um o

verl

ying

ri

ver t

erra

ce

Chal

k in

riv

er te

rrac

e de

posi

t in

sout

hern

par

t of

are

a 3.

7 5.

6 4.

5 68

.7

26.8

14

4 8

064

000

13 3

70 0

00

41

2 A

lluvi

um o

verl

ying

ri

ver t

erra

ce

Occ

asio

nal c

halk

in r

iver

te

rrac

e de

posi

t 4.

0 2.

8 5.

4 51

.3

43.3

49

9 13

772

400

22

770

000

CR/10/049

26

8 Land use impacts on resource volumes (Stage 5)8.1 MINERAL PLANNING PERMISSIONS

The mineral planning permission areas, which are based on data collected previously by BGS and Lincolnshire County Council and updated by Lincolnshire County Council to reflect any mineral planning permissions approved since 2002, have been used to exclude known mineral reserves and worked out areas. Planning permissions (shown in Appendix 2.9) were subtracted from the mineral resource areas. The figures for estimated resource volumes and tonnages were then recalculated using the method described in Section 7.1. The results of these re-calculations are given in Table 13.

Although there are a large number of planning permissions which have already been granted there remains a significant area of mineral resource which is as yet unworked; Table 11 shows the remaining areas by grade.

The majority of mineral planning permissions fall within areas identified in this report as resource (Grade 1 or Grade 2 potential). There are exceptions. For example, in the Market Deeping area close to Polygon ID 1, investigation demonstrated that although the borehole results suggest a resource with a low percentage of fines and little overburden, the deposit thinned to around 1.5m thickness. Therefore, this thinner area of resource was not enveloped by the polygon due to it not meeting the criteria in thickness, but the presence of planning permissions demonstrate that it has been worked. This is likely to be down to other non-geological factors, such as proximity to Peterborough, access to land and the rural nature of the site.

Table 11: Area of sand and gravel resource after designated areas are removed

Grade Total area (ha)

Remaining resource area:

after planning permission areas removed (ha)

after planning permission and urban areas removed (ha)

Grade 1 Indicated 29 897 27 672 25 673

Grade 1 Inferred 7 934 7 511 6 987

Grade 2 Indicated 1 392 1 389 1 291

Grade 2 Inferred 4 976 4 866 4 642

Total Grade 1 & 2 Resource 44 199 41 438 38 593

8.2 URBAN AREASAlthough consideration could be given in the calculations to other planning features (for example, urban areas and major transport links) the distribution of the mineral resources suggest that these factors will have little impact on the volumes of resource available as urban settlements in Lincolnshire are generally small.

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Only 8% of the total resource area has been sterilised by urban areas (see Table 11 and Appendix 2.10 for further details).

8.3 AREAS WITH ENVIRONMENTAL DESIGNATIONSLincolnshire is rich in environmentally designated areas both of national and international importance including the Lincolnshire Wolds Area of Outstanding Natural Beauty and a number of RAMSAR, Special Protection Areas and Special Areas of Conservation. Most of these areas do not coincide with the sand and gravel resources. The areas of environmental assets and mineral resources are shown in Table 12.

Table 12: Areas where mineral sand and gravel resources overlap with environmental designations

Designation

Areaof overlap

Area of Conservation(Ha)

Ramsar(Ha)

Special Protection Area (Ha)

Area of Outstanding Natural Beauty (Ha)

SSSI (Ha)

Grade 1 Indicated 1.5 (a) 0 0 0 483

Grade 1 Inferred 0 0 0 0 17

Grade 2 Indicated 0 0 0 0 0

Grade 2 Inferred 0 0 0 0 38

(a) Area also designated as an SSSI.

CR

/10/

049

28

Tab

le 1

3: V

olum

e an

d es

timat

ed to

nnag

es fo

r gr

ade

1 an

d 2

reso

urce

are

as m

inus

are

as w

ith m

iner

al p

lann

ing

perm

issi

ons a

nd u

rban

are

as

ID

Gra

de

Tota

l Ind

icat

ed R

esou

rce

Area

In

dica

ted

reso

urce

s m

inus

pla

nnin

g pe

rmis

sion

s In

dica

ted

Reso

urce

s m

inus

pla

nnin

g pe

rmis

sion

s an

d ur

ban

area

s

Are

a (h

a)

Estim

ated

Vol

ume

(m

3 )Es

timat

ed

Tonn

age

Are

a (h

a)

Estim

ated

vol

ume

(m3 )

Estim

ated

to

nnag

e A

rea

(ha)

Es

timat

ed

volu

me

(m3 )

Estim

ated

to

nnag

e

1 1

6 89

8 23

2 40

0 00

0 38

3 50

0 00

0 6

166

209

600

000

345

800

000

5 58

4 18

8 10

0 00

0 31

0 40

0 00

0

2 1

6 50

3 35

5 10

0 00

0 58

5 90

0 00

0 5

437

296

900

000

489

900

000

4 48

6 24

4 90

0 00

0 40

4 10

0 00

0

3 1

808

42 6

00 0

00

70 3

00 0

00

809

42 6

00 0

00

70 3

00 0

00

807

42 5

30 0

00

70 2

00 0

00

4 1

2 93

7 20

6 70

0 00

0 34

1 10

0 00

0 2

655

185

800

000

306

600

000

2 59

1 18

1 40

0 00

0 29

9 30

0 00

0

7 1

6 84

5 42

0 30

0 00

0 69

3 50

0 00

0 6

839

419

900

000

692

800

000

6 73

4 41

3 50

0 00

0 68

2 30

0 00

0

8 1

1 12

0 66

980

000

11

0 50

0 00

0 1

074

64 2

00 0

00

105

900

000

1 02

5 61

300

000

1

011

200

000

9 1

1 64

2 79

800

000

13

1 70

0 00

0 1

613

78 4

00 0

00

129

400

000

1 41

7 68

900

000

11

3 70

0 00

0

15

1 1

876

114

400

000

188

800

000

1 87

1 11

4 10

0 00

0 18

8 30

0 00

0 1

833

111

800

000

184

500

000

21

1 39

1 23

000

000

38

000

000

38

4 22

600

000

37

300

000

38

5 22

600

000

37

300

000

59

1 81

3 22

300

000

36

800

000

81

3 22

300

000

36

800

000

81

0 22

200

000

36

600

000

Tota

l Gra

de 1

29

833

1

563

580

000

2 58

0 10

0 00

0 27

661

1

456

400

000

2 40

3 10

0 00

0 25

672

1

357

230

000

3 03

6 00

0 00

0

5 2

749

22 5

00 0

00

37 1

00 0

00

746

22 4

00 0

00

37 0

00 0

00

663

19 9

00 0

00

32 8

00 0

00

37

2 14

4 8

100

000

13 3

70 0

00

144

8 10

0 00

0 13

400

000

12

9 7

200

000

11 9

00 0

00

41

2 49

9 13

800

000

22

770

000

49

9 13

800

000

22

800

000

49

9 13

800

000

22

800

000

Tota

l Gra

de 2

1

392

44 4

00 0

00

73 2

40 0

00

1 38

9 44

300

000

73

200

000

1

291

40 9

00 0

00

67 5

00 0

00

CR/10/049

29

9 ConclusionsThe raw data contained in Mineral Assessment Reports covering substantial parts of the County proved an excellent basis for reassessing the mineral resources of those areas.

Having been informed by the results of an aggregates industry consultation, the reassessment identified areas containing Grade 1 resources (i.e. lie within 10 m of the surface, have an overburden to resource ratio of 1:1 or better, and contain less than 15% ‘fines’), Grade 2 resources (within 10 m of the surface, overburden to resource ratio of 2:1 or better, containing less than 30% ‘fines’) and Unproven resources (areas thought likely to contain suitable sand and gravel resources but with insufficient data classify or quantify them).

The results of the reassessment were incorporated into a GIS (Geographical Information System). The GIS contains vector data delineating ‘resource polygons’ attributed with data relating to the quality, quantity and physical properties of the resource. Summary tables of these attributes are included in this report and a selection of maps generated from the GIS are also appended.

The reassessment showed that the principal areas containing Grade 1 and 2 resources are:

1. An area of fluvial deposits in the Trent Valley north of Gainsborough

2. An area of fluvial deposits lying between the Rivers Trent and Witham, to the west of Lincoln

3. An area sub-alluvial, fluvial deposits underlying the floodplain of the River Witham south-east of Lincoln

4. Due to the deposit being sub-alluvial, wet working will be required. Industry voiced their concerns over issues concerning the removal of the wet alluvial overburden

5. Spreads of river terrace deposits and glaciofluvial deposits around Woodhall Spa

6. A wide spread of fluvial deposits around Market Deeping in the south of the county.

Of these, the resources around Market Deeping, west of Lincoln and around Woodhall Spa have been, or are currently, worked. The thick and extensive sand and gravel resource that underlie the Witham floodplain southeast of Lincoln have not been exploited, presumably because of they are entirely sub-alluvial and would require wet-working. The resources in the Trent Valley north of Gainsborough are thick, extensive and likely to be of good quality but are not currently worked. When consulted, the aggregate industry gave a variety of reasons for the apparent lack of interest in this area, including access issues, distance from market, difficulties of working, and adequate reserves elsewhere. Nevertheless, several companies might consider working in the Gainsborough area if suitable opportunity arose.

Outside the area of the county that had been the subject of MAR surveys, the available data proved too sparse and unfavourably distributed to systematically identify and classify sand and gravel resources. However, such data as was available indicated that suitable resources may exist in fluvial deposits around Sleaford, between Billingborough and Dowsby and near Long Bennington. Also, silica sand resources may be present contained within the blown sand deposits which occur extensively north of Market Rasen (although analysis of the physical and chemical properties of this deposit will be required in order to validate this).

CR

/10/

049

30

App

endi

x 1

Det

ails

of i

ndus

try su

rvey

resp

onse

s

Old

BG

S cr

iteria

(in

MA

Rs)

The

depo

sit s

houl

d av

erag

e >1

m th

ickn

ess.

Rat

io o

f ove

rbur

den

to m

iner

al sh

ould

not

ex

ceed

3:1

.Th

e pr

opor

tion

of fi

nes s

houl

d no

t ex

ceed

40

per c

ent.

The

depo

sit s

houl

d lie

with

in

25 m

of t

he su

rfac

e.

Prop

osed

Crit

eria

The

depo

sit s

houl

d av

erag

e >2

m th

ickn

ess.

Rat

io o

f ove

rbur

den

to m

iner

al sh

ould

not

ex

ceed

1:1

.Th

e pr

opor

tion

of fi

nes s

houl

d no

t ex

ceed

40

per c

ent.

The

depo

sit s

houl

d lie

with

in

5-10

m o

f the

surf

ace.

Res

pons

e1

Agr

ee3:

1 ca

n be

reas

onab

le, a

nd fu

ture

tren

ds

will

be

to g

reat

er th

ickn

esse

s.

Nee

d to

def

ine

“fin

es”.

If sa

nd –

now

take

n as

-4m

m, a

n in

dica

tive

limit

of c

70%

can

be

reas

onab

le in

a sa

nd &

gra

vel

depo

sit.

If re

ferr

ing

to si

lt, -

75 m

icro

ns, a

n in

dica

tive

limit

of c

20%

is re

ason

able

de

pend

ing

on th

e na

ture

(e.g

. cla

y co

nten

t) of

the

silt.

Agr

ee

Res

pons

e 2

At l

east

2m

.Crit

eria

ba

sed

on p

lann

ing

and

arch

aeol

ogy

cost

s.3:

1A

gree

5m

max

Res

pons

e 3

This

gen

eral

ly d

epen

ds

on th

e ov

erbu

rden

to

min

eral

ratio

.

Gen

eral

ly fo

r san

d an

d gr

avel

we

wou

ld

cons

ider

an

econ

omic

cut

off

of <

2: 1

ov

erbu

rden

to m

iner

al ra

tio.

We

wou

ld g

ener

ally

con

side

r 15%

fin

es (c

lays

/ silt

s) a

s the

cut

-off

. H

owev

er, a

hig

her %

rese

rve

may

st

ill b

e ec

onom

ic e

.g. u

se a

s a fi

ll m

ater

ial o

r if i

t for

ms p

art o

f a la

rger

, be

tter q

ualit

y re

serv

e.

Agr

ee

Res

pons

e 4

Dis

agre

e un

less

ap

plic

able

to w

hole

re

serv

e. T

here

may

be

mar

gina

l are

as o

n la

rger

de

posi

tsw

hich

can

be

wor

ked.

Usu

ally

wor

k on

2:1

. Thi

n de

posi

ts ~

1m

with

<0.

5m o

verb

urde

n m

ay b

e re

cove

rabl

e.A

gree

Agr

eed

Res

pons

e5

Agr

eeA

gree

Am

iner

al o

pera

tor i

s ver

y un

likel

y to

go

for a

gre

enfie

ld d

evel

opm

ent i

f the

A

gree

CR

/10/

049

31

fines

con

tent

is o

ver 1

5%, t

he

abso

lute

max

imum

bei

ng 2

0.Th

e B

GS

curr

ent l

imit

is w

ay to

o hi

gh.

Res

pons

e6

Tend

to a

gree

but

I am

su

re th

ere

will

be

exce

ptio

ns p

artic

ular

ly if

it

is e

asy

to e

xcav

ate,

an

exte

nsio

n of

exi

stin

g si

te

etc.

Agr

ee –

but o

n an

y si

te sh

ould

be

aver

age

over

who

le si

te ra

ther

than

ratio

in o

ne

loca

tion.

Sho

uld

be u

sed

with

car

e to

de

linea

te p

oten

tial r

esou

rce

area

s in

deta

il.

Ove

rbur

den

is a

lso

a re

stor

atio

n m

ater

ial

and

som

e th

icke

r ove

rbur

den

may

be

adva

ntag

eous

in a

ny si

te.

This

will

dep

end

on p

roce

ssin

g an

d en

d us

e, so

no

real

com

men

t exc

ept

that

it d

oes s

eem

hig

h fo

r an

aver

age

amou

nt.

The

sam

e co

mm

ents

as

abov

e w

ould

app

ly.

I sus

pect

that

this

mea

ns th

e to

p of

gra

vel i

n w

hich

cas

e it

is p

roba

bly

reas

onab

le.

A

quic

k gl

ance

at s

ome

of th

e M

AU

repo

rts sh

ows g

rave

l an

d sa

nd to

dep

ths o

f ove

r 15

m in

pla

ces.

Cle

arly

it

does

n’t m

atte

r how

dee

p th

e ba

se o

f the

gra

vel i

s if i

t has

sa

tisfie

d th

e ot

her c

riter

ia.

I do

n’t k

now

why

they

nee

d to

put

the

5m in

.

Res

pons

e7

Agr

ee W

e do

n’t h

ave

an

‘ave

rage

thic

knes

s’

crite

ria b

ut re

quire

de

posi

t to

be g

reat

er th

an

1m th

ick.

Agr

ee

Dis

agre

e. A

gain

we

don’

t hav

e fix

ed

crite

ria a

s it d

epen

ds o

n ot

her f

acto

rs

(e.g

.: w

heth

er fi

nes a

re si

lts o

r cla

ys)

but 3

0% is

mor

e re

alis

tic.

Agr

ee. D

on’t

have

fixe

d cr

iteria

but

10m

is a

real

istic

m

axim

um.

CR/10/049

32

Appendix 2 Map outputs

CR/10/049

33

CR

/10/

049

34

App

endi

x 3

Det

ails

of a

ll m

iner

al re

sour

ce a

reas

iden

tifie

d in

stud

y

ID

Gra

de

Num

ber o

f Bo

reho

les

Geo

logy

Bo

reho

le

Geo

logy

Not

es

Mea

n O

verb

urde

n th

ickn

ess

(m)

Mea

n O

verb

urde

n th

ickn

ess

(m)

Mea

n Fi

nes

%

Mea

n Sa

nd %

M

ean

Gra

vel %

A

rea

(ha)

Es

timat

ed

Volu

me

(m3 )

Estim

ated

to

nnag

e

1 G

rade

1

70

Rive

r ter

race

O

ccas

iona

l cha

lk

1.1

3.4

5 50

45

6

959

234

521

100

387

000

000

2 G

rade

1

57

Rive

r ter

race

N

A

0.5

5.5

6 55

40

6

504

355

063

800

585

900

000

3 G

rade

1

9 Ri

ver t

erra

ce

NA

0.

6 5.

3 4

80

16

809

42 5

81 6

00

70 3

00 0

00

4 G

rade

1

32

Rive

r ter

race

O

ccas

iona

l coa

l sp

ecks

0.

7 7.

0 4

94

2 2

937

206

764

800

341

100

000

7 G

rade

1

51

Allu

vium

ov

erly

ing

river

te

rrac

e N

A

2.8

6.1

4 66

30

6

846

420

283

000

693

500

000

8 G

rade

1

13

Gla

ciof

luvi

al

Loca

lised

cha

lk

0.6

6.0

5 84

11

1

121

66 9

76 0

00

110

500

000

9 G

rade

1

13

Gla

ciof

luvi

al

Loca

lised

cha

lk

1.0

4.9

6 72

23

1

642

79 8

01 2

00

131

700

000

15

Gra

de 1

14

A

lluvi

um

over

lyin

g riv

er

terr

ace

Chal

k in

riv

er

terr

ace

depo

sit

3.1

6.1

4 75

20

1

876

114

436

000

188

800

000

18

Gra

de 1

12

Ri

ver t

erra

ce

Chal

k 8.

7 4.

7 5

63

32

884

(a)

(a)

21

Gra

de 1

5

Allu

vium

ov

erly

ing

river

te

rrac

e N

A

1.2

5.9

7 65

28

39

1 22

990

800

38

000

000

59

Gra

de 1

7

Blow

n sa

nd

NA

0.

2 2.

7 6

94

0 81

4 22

276

200

36

800

000

11

Gra

de 1

4

Rive

r ter

race

N

A

0.5

2.6

8 70

21

37

2 (a

) (a

)

12

Gra

de 1

1

Rive

r ter

race

N

A

0.8

2.4

11

87

1 13

6 (a

) (a

)

CR

/10/

049

35

ID

Gra

de

Num

ber o

f Bo

reho

les

Geo

logy

Bo

reho

le

Geo

logy

Not

es

Mea

n O

verb

urde

n th

ickn

ess

(m)

Mea

n O

verb

urde

n th

ickn

ess

(m)

Mea

n Fi

nes

%

Mea

n Sa

nd %

M

ean

Gra

vel %

A

rea

(ha)

Es

timat

ed

Volu

me

(m3 )

Estim

ated

to

nnag

e

13

Gra

de 1

1

Rive

r ter

race

N

A

0.4

3.2

9 62

29

36

(a

) (a

)

14

Gra

de 1

3

Allu

vium

ov

erly

ing

river

te

rrac

e N

A

3.8

6.2

11

86

2 26

6 (a

) (a

)

16

Gra

de 1

3

Gla

ciof

luvi

al

NA

2.

6 97

.3

2 98

0

147

(a)

(a)

17

Gra

de 1

4

Rive

r ter

race

ov

erly

ing

glac

ioflu

vial

N

A

0.8

4.4

5 67

28

48

2 (a

) (a

)

19

Gra

de 1

2

Rive

r ter

race

N

A

0.5

2.5

3 57

40

11

1 (a

) (a

)

20

Gra

de 1

1

Rive

r ter

race

Ch

alk

1.0

3.9

4 55

41

65

(a

) (a

)

22

Gra

de 1

4

Rive

r ter

race

N

A

0.8

4.1

14

58

29

408

(a)

(a)

23

Gra

de 1

1

Gla

ciof

luvi

al

NA

0.

5 3.

3 6

70

24

346

(a)

(a)

24

Gra

de 1

2

Gla

ciof

luvi

al

NA

0.

6 5.

9 4

62

34

64

(a)

(a)

25

Gra

de 1

2

Allu

vium

ov

erly

ing

river

te

rrac

e N

A

0.6

2.4

6 73

21

13

6 (a

) (a

)

26

Gra

de 1

2

Gla

ciof

luvi

al

NA

0.

4 3.

2 7

57

36

120

(a)

(a)

29

Gra

de 1

2

Rive

r ter

race

N

A

0.5

5.5

6 83

11

14

3 (a

) (a

)

30

Gra

de 1

1

Allu

vium

ov

erly

ing

river

te

rrac

e N

A

1.4

5.1

5 92

3

77

(a)

(a)

33

Gra

de 1

3

Gla

ciof

luvi

al

NA

2.

1 4.

4 7

88

5 42

3 (a

) (a

)

40

Gra

de 1

1

Rive

r ter

race

Sm

all a

mou

nts

of c

halk

0.

5 3.

6 2

58

40

136

(a)

(a)

CR

/10/

049

36

ID

Gra

de

Num

ber o

f Bo

reho

les

Geo

logy

Bo

reho

le

Geo

logy

Not

es

Mea

n O

verb

urde

n th

ickn

ess

(m)

Mea

n O

verb

urde

n th

ickn

ess

(m)

Mea

n Fi

nes

%

Mea

n Sa

nd %

M

ean

Gra

vel %

A

rea

(ha)

Es

timat

ed

Volu

me

(m3 )

Estim

ated

to

nnag

e

43

Gra

de 1

2

Gla

ciof

luvi

al

NA

0.

5 4.

1 3

57

40

98

(a)

(a)

44

Gra

de 1

2

Gla

ciof

luvi

al

NA

0.

3 3.

8 7

53

40

235

(a)

(a)

45

Gra

de 1

1

Gla

ciof

luvi

al

NA

0.

7 3.

8 6

61

33

114

(a)

(a)

46

Gra

de 1

1

Rive

r ter

race

N

A

0.7

5.1

10

59

31

26

(a)

(a)

47

Gra

de 1

1

Allu

vium

ov

erly

ing

river

te

rrac

e N

A

2.8

3.6

2 27

71

95

(a

) (a

)

48

Gra

de 1

1

Gla

ciof

luvi

al

NA

0.

1 4.

1 15

47

39

46

(a

) (a

)

50

Gra

de 1

2

Rive

r ter

race

N

A

0.7

3.5

3 56

41

39

0 (a

) (a

)

51

Gra

de 1

3

Gla

ciof

luvi

al

NA

1.

6 3.

4 6

70

25

576

(a)

(a)

52

Gra

de 1

1

Blow

n sa

nd

NA

0.

0 2.

6 2

98

0 71

(a

) (a

)

53

Gra

de 1

1

Gla

ciof

luvi

al

NA

0.

5 6.

6 6

74

20

278

(a)

(a)

54

Gra

de 1

2

Gla

ciof

luvi

al

NA

0.

5 6.

2 4

90

5 20

4 (a

) (a

)

57

Gra

de 1

1

Gla

ciof

luvi

al

NA

0.

9 3.

3 6

65

29

41

(a)

(a)

58

Gra

de 1

1

Gla

ciof

luvi

al

NA

0.

4 3.

0 9

89

2 68

(a

) (a

)

61

Gra

de 1

1

Gla

ciof

luvi

al

NA

0.

0 2.

1 14

71

15

41

(a

) (a

)

62

Gra

de 1

3

Rive

r ter

race

N

A

0.9

3.2

12

49

39

191

(a)

(a)

64

Gra

de 1

2

Blow

n sa

nd

NA

0.

4 3.

2 9

87

4 25

2 (a

) (a

)

65

Gra

de 1

1

Gla

ciof

luvi

al

NA

0.

2 4.

4 8

72

20

43

(a)

(a)

CR

/10/

049

37

ID

Gra

de

Num

ber o

f Bo

reho

les

Geo

logy

Bo

reho

le

Geo

logy

Not

es

Mea

n O

verb

urde

n th

ickn

ess

(m)

Mea

n O

verb

urde

n th

ickn

ess

(m)

Mea

n Fi

nes

%

Mea

n Sa

nd %

M

ean

Gra

vel %

A

rea

(ha)

Es

timat

ed

Volu

me

(m3 )

Estim

ated

to

nnag

e

66

Gra

de 1

1

Gla

ciof

luvi

al

NA

0.

3 2.

5 6

61

33

30

(a)

(a)

68

Gra

de 1

1

Rive

r ter

race

Sm

all a

mou

nts

of c

halk

1.

0 2.

8 3

48

49

42

(a)

(a)

69

Gra

de 1

2

Gla

ciof

luvi

al

NA

0.

4 2.

6 4

93

3 87

(a

) (a

)

74

Gra

de 1

1

Gla

ciof

luvi

al

NA

0.

4 2.

9 9

54

37

49

(a)

(a)

75

Gra

de 1

1

Rive

r ter

race

N

A

0.6

2.4

12

78

11

63

(a)

(a)

78

Gra

de 1

1

Rive

r ter

race

N

A

1.1

2.0

5 76

20

15

0 (a

) (a

)

81

Gra

de 1

1

Gla

ciof

luvi

al

NA

0.

6 2.

2 4

51

45

57

(a)

(a)

82

Gra

de 1

3

Gla

ciof

luvi

al

NA

0.

8 3.

0 5

65

29

330

(a)

(a)

5 G

rade

2

8 Ri

ver t

erra

ce

NA

0.

8 3.

0 21

65

14

74

9 22

470

000

37

100

000

32

Gra

de 2

11

A

lluvi

um

over

lyin

g riv

er

terr

ace

Chal

k in

riv

er

terr

ace

depo

sit

in s

outh

ern

part

of

are

a

5.7

4.3

4 66

30

1

298

(a)

(a)

34

Gra

de 2

6

Allu

vium

ov

erly

ing

river

te

rrac

e

Chal

k in

riv

er

terr

ace

depo

sit

in s

outh

ern

part

of

are

a

5.8

4.0

7 70

23

49

9 (a

) (a

)

37

Gra

de 2

93

A

lluvi

um

over

lyin

g riv

er

terr

ace

Chal

k in

riv

er

terr

ace

depo

sit

in s

outh

ern

part

of

are

a

3.7

5.6

5 69

27

14

4 8

064

000

13 3

70 0

00

41

Gra

de 2

5

Allu

vium

ov

erly

ing

river

te

rrac

e

Occ

asio

nal c

halk

in

riv

er te

rrac

e de

posi

t 4.

0 2.

8 5

51

43

499

13 7

72 4

00

22 7

70 0

00

CR

/10/

049

38

ID

Gra

de

Num

ber o

f Bo

reho

les

Geo

logy

Bo

reho

le

Geo

logy

Not

es

Mea

n O

verb

urde

n th

ickn

ess

(m)

Mea

n O

verb

urde

n th

ickn

ess

(m)

Mea

n Fi

nes

%

Mea

n Sa

nd %

M

ean

Gra

vel %

A

rea

(ha)

Es

timat

ed

Volu

me

(m3 )

Estim

ated

to

nnag

e

10

Gra

de 2

2

Gla

ciof

luvi

al

Loca

lised

cha

lk

0.9

4.0

17

61

22

261

(a)

(a)

27

Gra

de 2

1

Gla

ciof

luvi

al

NA

0.

9 3.

6 16

84

0

32

(a)

(a)

28

Gra

de 2

4

Allu

vium

ov

erly

ing

river

te

rrac

e N

A

4.4

3.5

2 41

56

32

0 (a

) (a

)

31

Gra

de 2

3

Allu

vium

ov

erly

ing

river

te

rrac

e N

A

4.7

4.1

1 67

32

31

6 (a

) (a

)

35

Gra

de 2

2

Allu

vium

ov

erly

ing

river

te

rrac

e

Chal

k in

riv

er

terr

ace

depo

sit

in s

outh

ern

part

of

are

a

5.0

6.5

4 67

29

17

2 (a

) (a

)

36

Gra

de 2

2

Allu

vium

ov

erly

ing

river

te

rrac

e

Chal

k in

riv

er

terr

ace

depo

sit

in s

outh

ern

part

of

are

a

5.0

5.0

12

88

0 33

8 (a

) (a

)

38

Gra

de 2

3

Allu

vium

ov

erly

ing

river

te

rrac

e

Chal

k in

riv

er

terr

ace

depo

sit

in s

outh

ern

part

of

are

a

6.0

4.0

5 52

43

24

9 (a

) (a

)

42

Gra

de 2

2

Allu

vium

ov

erly

ing

river

te

rrac

e

Occ

asio

nal c

halk

in

riv

er te

rrac

e de

posi

t 3.

2 2.

3 5

60

35

146

(a)

(a)

49

Gra

de 2

1

Gla

ciof

luvi

al

NA

0.

1 2.

7 15

42

43

69

(a

) (a

)

55

Gra

de 2

1

Gla

ciof

luvi

al

NA

0.

5 6.

6 6

74

20

350

(a)

(a)

56

Gra

de 2

3

Gla

ciof

luvi

al

NA

0.

5 5.

1 10

86

5

280

(a)

(a)

60

Gra

de 2

2

Blow

n sa

nd

NA

0.

4 2.

3 24

74

2

333

(a)

(a)

CR

/10/

049

39

ID

Gra

de

Num

ber o

f Bo

reho

les

Geo

logy

Bo

reho

le

Geo

logy

Not

es

Mea

n O

verb

urde

n th

ickn

ess

(m)

Mea

n O

verb

urde

n th

ickn

ess

(m)

Mea

n Fi

nes

%

Mea

n Sa

nd %

M

ean

Gra

vel %

A

rea

(ha)

Es

timat

ed

Volu

me

(m3 )

Estim

ated

to

nnag

e

63

Gra

de 2

4

Rive

r ter

race

N

A

1.0

3.3

16

48

36

212

(a)

(a)

67

Gra

de 2

1

Gla

ciof

luvi

al

NA

1.

0 2.

2 16

84

1

82

(a)

(a)

71

Gra

de 2

1

Rive

r ter

race

O

ccas

iona

l cha

lk

0.3

2.9

15

50

35

6 (a

) (a

)

73

Gra

de 2

1

Gla

ciof

luvi

al

NA

0.

3 3.

5 21

76

3

12

(a)

(a)

6 In

ferr

ed

with

out

0 A

lluvi

um

over

lyin

g riv

er

terr

ace

No

bore

hole

da

ta

0.0

0.0

0 0

0 38

6 (a

) (a

)

70

Infe

rred

w

ithou

t 0

Rive

r ter

race

N

o bo

reho

le

data

0.

0 0.

0 0

0 0

2 (a

) (a

)

72

Infe

rred

w

ithou

t 0

Rive

r ter

race

N

o bo

reho

le

data

0.

0 0.

0 0

0 0

10

(a)

(a)

76

Infe

rred

w

ithou

t 0

Rive

r ter

race

N

o bo

reho

le

data

0.

0 0.

0 0

0 0

76

(a)

(a)

77

Infe

rred

w

ithou

t 0

Rive

r ter

race

N

o bo

reho

le

data

0.

0 0.

0 0

0 0

115

(a)

(a)

79

Infe

rred

w

ithou

t 0

Gla

ciof

luvi

al

No

bore

hole

da

ta

0.0

0.0

0 0

0 52

(a

) (a

)

80

Infe

rred

w

ithou

t 0

Allu

vium

ov

erly

ing

river

te

rrac

e

No

bore

hole

da

ta

0.0

0.0

0 0

0 58

3 (a

) (a

)

83

Infe

rred

w

ithou

t 0

Blow

n sa

nd

No

bore

hole

da

ta

0.0

0.0

0 0

0 0

(a)

(a)

84

Infe

rred

w

ithou

t 0

Rive

r ter

race

N

o bo

reho

le

data

0.

0 0.

0 0

0 0

1 (a

) (a

)

85

Infe

rred

w

ithou

t 0

Blow

n sa

nd

No

bore

hole

da

ta

0.0

0.0

0 0

0 1

(a)

(a)

86

Infe

rred

w

ithou

t 0

Rive

r ter

race

N

o bo

reho

le

data

0.

0 0.

0 0

0 0

1 (a

) (a

)

CR

/10/

049

40

ID

Gra

de

Num

ber o

f Bo

reho

les

Geo

logy

Bo

reho

le

Geo

logy

Not

es

Mea

n O

verb

urde

n th

ickn

ess

(m)

Mea

n O

verb

urde

n th

ickn

ess

(m)

Mea

n Fi

nes

%

Mea

n Sa

nd %

M

ean

Gra

vel %

A

rea

(ha)

Es

timat

ed

Volu

me

(m3 )

Estim

ated

to

nnag

e

87

Infe

rred

w

ithou

t 0

Blow

n sa

nd

No

bore

hole

da

ta

0.0

0.0

0 0

0 1

(a)

(a)

88

Infe

rred

w

ithou

t 0

Blow

n sa

nd

No

bore

hole

da

ta

0.0

0.0

0 0

0 1

(a)

(a)

89

Infe

rred

w

ithou

t 0

Rive

r ter

race

N

o bo

reho

le

data

0.

0 0.

0 0

0 0

2 (a

) (a

)

90

Infe

rred

w

ithou

t 0

Blow

n sa

nd

No

bore

hole

da

ta

0.0

0.0

0 0

0 3

(a)

(a)

91

Infe

rred

w

ithou

t 0

Rive

r ter

race

N

o bo

reho

le

data

0.

0 0.

0 0

0 0

4 (a

) (a

)

92

Infe

rred

w

ithou

t 0

Rive

r ter

race

N

o bo

reho

le

data

0.

0 0.

0 0

0 0

4 (a

) (a

)

93

Infe

rred

w

ithou

t 0

Rive

r ter

race

N

o bo

reho

le

data

0.

0 0.

0 0

0 0

5 (a

) (a

)

94

Infe

rred

w

ithou

t 0

Gla

ciof

luvi

al

No

bore

hole

da

ta

0.0

0.0

0 0

0 6

(a)

(a)

95

Infe

rred

w

ithou

t 0

Gla

ciof

luvi

al

No

bore

hole

da

ta

0.0

0.0

0 0

0 6

(a)

(a)

96

Infe

rred

w

ithou

t 0

Rive

r ter

race

N

o bo

reho

le

data

0.

0 0.

0 0

0 0

6 (a

) (a

)

97

Infe

rred

w

ithou

t 0

Rive

r ter

race

N

o bo

reho

le

data

0.

0 0.

0 0

0 0

7 (a

) (a

)

98

Infe

rred

w

ithou

t 0

Gla

ciof

luvi

al

No

bore

hole

da

ta

0.0

0.0

0 0

0 7

(a)

(a)

99

Infe

rred

w

ithou

t 0

Rive

r ter

race

N

o bo

reho

le

data

0.

0 0.

0 0

0 0

8 (a

) (a

)

100

Infe

rred

w

ithou

t 0

Gla

ciof

luvi

al

No

bore

hole

da

ta

0.0

0.0

0 0

0 10

(a

) (a

)

101

Infe

rred

w

ithou

t 0

Rive

r ter

race

N

o bo

reho

le

data

0.

0 0.

0 0

0 0

10

(a)

(a)

CR

/10/

049

41

ID

Gra

de

Num

ber o

f Bo

reho

les

Geo

logy

Bo

reho

le

Geo

logy

Not

es

Mea

n O

verb

urde

n th

ickn

ess

(m)

Mea

n O

verb

urde

n th

ickn

ess

(m)

Mea

n Fi

nes

%

Mea

n Sa

nd %

M

ean

Gra

vel %

A

rea

(ha)

Es

timat

ed

Volu

me

(m3 )

Estim

ated

to

nnag

e

102

Infe

rred

w

ithou

t 0

Rive

r ter

race

N

o bo

reho

le

data

0.

0 0.

0 0

0 0

13

(a)

(a)

103

Infe

rred

w

ithou

t 0

Rive

r ter

race

N

o bo

reho

le

data

0.

0 0.

0 0

0 0

14

(a)

(a)

104

Infe

rred

w

ithou

t 0

Gla

ciof

luvi

al

No

bore

hole

da

ta

0.0

0.0

0 0

0 16

(a

) (a

)

105

Infe

rred

w

ithou

t 0

Rive

r ter

race

N

o bo

reho

le

data

0.

0 0.

0 0

0 0

20

(a)

(a)

106

Infe

rred

w

ithou

t 0

Rive

r ter

race

N

o bo

reho

le

data

0.

0 0.

0 0

0 0

23

(a)

(a)

107

Infe

rred

w

ithou

t 0

Rive

r ter

race

N

o bo

reho

le

data

0.

0 0.

0 0

0 0

22

(a)

(a)

108

Infe

rred

w

ithou

t 0

Gla

ciof

luvi

al

No

bore

hole

da

ta

0.0

0.0

0 0

0 25

(a

) (a

)

109

Infe

rred

w

ithou

t 0

Rive

r ter

race

N

o bo

reho

le

data

0.

0 0.

0 0

0 0

30

(a)

(a)

110

Infe

rred

w

ithou

t 0

Rive

r ter

race

N

o bo

reho

le

data

0.

0 0.

0 0

0 0

35

(a)

(a)

111

Infe

rred

w

ithou

t 0

Rive

r ter

race

N

o bo

reho

le

data

0.

0 0.

0 0

0 0

66

(a)

(a)

112

Infe

rred

w

ithou

t 0

Rive

r ter

race

N

o bo

reho

le

data

0.

0 0.

0 0

0 0

87

(a)

(a)

113

Infe

rred

w

ithou

t 0

Gla

ciof

luvi

al

No

bore

hole

da

ta

0.0

0.0

0 0

0 13

(a

) (a

)

114

Infe

rred

w

ithou

t 0

Rive

r ter

race

N

o bo

reho

le

data

0.

0 0.

0 0

0 0

30

(a)

(a)

115

Infe

rred

w

ithou

t 0

Rive

r ter

race

N

o bo

reho

le

data

0.

0 0.

0 0

0 0

43

(a)

(a)

116

Infe

rred

w

ithou

t 0

Rive

r ter

race

N

o bo

reho

le

data

0.

0 0.

0 0

0 0

92

(a)

(a)

CR

/10/

049

42

ID

Gra

de

Num

ber o

f Bo

reho

les

Geo

logy

Bo

reho

le

Geo

logy

Not

es

Mea

n O

verb

urde

n th

ickn

ess

(m)

Mea

n O

verb

urde

n th

ickn

ess

(m)

Mea

n Fi

nes

%

Mea

n Sa

nd %

M

ean

Gra

vel %

A

rea

(ha)

Es

timat

ed

Volu

me

(m3 )

Estim

ated

to

nnag

e

117

Infe

rred

w

ithou

t 0

Rive

r ter

race

N

o bo

reho

le

data

0.

0 0.

0 0

0 0

8 (a

) (a

)

118

Infe

rred

w

ithou

t 0

Rive

r ter

race

N

o bo

reho

le

data

0.

0 0.

0 0

0 0

18

(a)

(a)

119

Infe

rred

w

ithou

t 0

Rive

r ter

race

N

o bo

reho

le

data

0.

0 0.

0 0

0 0

24

(a)

(a)

120

Infe

rred

w

ithou

t 0

Rive

r ter

race

N

o bo

reho

le

data

0.

0 0.

0 0

0 0

29

(a)

(a)

121

Infe

rred

w

ithou

t 0

Rive

r ter

race

N

o bo

reho

le

data

0.

0 0.

0 0

0 0

38

(a)

(a)

122

Infe

rred

w

ithou

t 0

Rive

r ter

race

N

o bo

reho

le

data

0.

0 0.

0 0

0 0

63

(a)

(a)

123

Infe

rred

w

ithou

t 0

Rive

r ter

race

N

o bo

reho

le

data

0.

0 0.

0 0

0 0

80

(a)

(a)

124

Infe

rred

w

ithou

t 0

Rive

r ter

race

N

o bo

reho

le

data

0.

0 0.

0 0

0 0

1 24

7 (a

) (a

)

125

Infe

rred

w

ithou

t 0

Gla

ciof

luvi

al

No

bore

hole

da

ta

0.0

0.0

0 0

0 55

(a

) (a

)

126

Infe

rred

w

ithou

t 0

Gla

ciof

luvi

al

No

bore

hole

da

ta

0.0

0.0

0 0

0 2

(a)

(a)

127

Infe

rred

w

ithou

t 0

Blow

n sa

nd

No

bore

hole

da

ta

0.0

0.0

0 0

0 22

7 (a

) (a

)

(a)

Not

eno

ugh

data

ava

ilabl

e to

cal

cula

te a

vol

ume

and

tonn

age

estim

ate.

CR/10/049

43

GlossaryAeolian: Sediments deposited after transport by wind.

Aggregate: Particles of rock which, when brought together in a bound or

unbound condition, form part or whole of a building or civil

engineering structure.

Alluvium: A general term for unconsolidated detrital material such as clay,

silt, sand and gravel, deposited by rivers and streams as sorted or

semi-sorted sediment in the stream-bed or on the floodplain.

Asset: Any environmental or cultural feature that society places a value

on and that may need to be considered when planning for

aggregates provision (for example National Nature Reserves,

Scheduled Ancient Monuments, Agricultural Land).

Boulder clay: A glacial deposit consisting of sub-angular pebbles and boulders

of all sizes embedded in stiff or hard reworked clay or rock

flour. The term ‘till’ is preferable because it covers the wide

range of lithologies included here and does not imply the

presence of either boulders or true clay.

Building sand: Sand with a grading suitable for use in mortars.

Clast: A rock fragment; commonly applied to a fragment of preexisting

rock included in a younger sediment.

Deposit: Indicates a mineral occurrence of some significance but which is

not closely defined.

Fines: Material finer than 60 microns, i.e. the silt and clay-sized

fraction, but in connection with aggregates it usually refers to

material finer than 75 microns.

Flint: Variety of chart occurring in the chalk of northern Europe.

Fluvial: Relating to a river; a deposit produced by the action of a river.

GIS: A Geographic Information System (GIS) is a computer based

system used to store, manipulate, analyse and spatial data.

Glaciofluvial: May be applied to sediment transported and deposited by

running water discharged from an ice mass.

Glacial deposits: Heterogeneous material transported by glaciers or icebergs and

deposited directly on land or in the sea without sorting of the

constituents

Grade: Size sorting category in which all the particles fall within

CR/10/049

44

specified size limits.

Grading: The proportions of different sizes present in aggregate,

established by sieve analysis; particle size distribution.

Gravel: Granular material between 4 and 80 mm; coarse aggregate.

Used for general and concrete applications.

Hoggin: Unprocessed mix of sand, gravel and clay, suitable for general

fill purposes.

Limestone: A sedimentary rock composed mainly of calcium carbonate

occurring as the mineral calcite.

Lithology: The general characteristics of a rock

Mineral: A naturally formed chemical element or compound and

normally having a characteristic crystal form and a definite

composition.

Mineral deposit: Generally synonymous with mineral resources but usually

applied to a readily identifiable mineral body i.e. more

geographically or spatially confined.

Mortar: A mixture of cement, water and fine aggregate, usually sand,

and may contain lime. Mortar is used for brick and blockwork

and for plastering and rendering.

Outcrop: The area over which a particular rock unit occurs at the surface,

whether visibly exposed or not.

Overburden: Waste rock, either loose or consolidated, overlying a mineral

deposit, which must be removed prior to extraction.

Planning features: Any relevant feature that may need to be taken into account

when planning for aggregates provision (for example roads,

urban areas, location of airports and airfields).

Quaternary: The latest era of geological time, from 2 Ma B.P. to the present,

largely represented in Britain by superficial deposits such as

glacial drift.

Recent: The current epoch in the earth’s history, comprising the 10,000

years or so since the end of the last glaciation.

Reserve: That part of a mineral resource that is economical to work and

has been fully evaluated on a systematic basis by drilling and

sampling and is free from legal or other obstruction that might

inhibit extraction.

Resource: Natural accumulations of minerals, or bodies of rock, that are or

may become of potential economic interest as a basis for the

CR/10/049

45

extraction of a commodity.

Sand: A granular material that is finer than 4 mm, but coarser than

0.063 mm.

Silt: A deposit which has the average grain size between that of sand

and clay.

Sorted: Referring to size distribution of unconsolidated sediments, e.g.

sands, gravels etc, size separation having taken place naturally.

Sorted, well: Having a relatively narrow size distribution free of coarse

particles and fine clays.

Sorted, poorly: Having a relatively wide size distribution.

Superficial deposit: Deposits formed on or close to the present land surface by

processes (e.g. glaciation) usually of Quaternary age. Their

distribution and thickness are related essentially to the surface

relief and not to the structure of the underlying bedrock.

Till: Unstratified, unsorted drift deposited directly by a glacier

without reworking by water from the glacier; comprises a

heterogeneous mixture of clay, sand, gravel and boulders.

CR/10/049

46

ReferencesBritish Geological Survey holds most of the references listed below, and copies may be obtained via the library service subject to copyright legislation (contact libuser@bgs.ac.uk for details).The library catalogue is available at: http://geolib.bgs.ac.uk.

HARRISON, D J, HENNEY, P J, CAMERON, D G, SPENCER, N A, STEADMAN, EJ, EVANS, D J, LOTT, G KAND HIGHLEY, D E. . 2002. Mineral Resource Information in Support of National, Regional and Local Planning: Lincolnshire

LINCOLNSHIRE COUNTY COUNCIL. 1991. Lincolnshire Minerals Local Plan.

MCEVOY, F M, STEADMAN, E.J., HARRISON, D.J., COOPER, A.H. 2004. Yorkshire and the Humber Region: sand and gravel resources and environmental assets. CR/04/216N

NOTTINGHAMSHIRE COUNTY COUNCIL. 2005. Nottinghamshire Minerals Local Plan.

Information sourcesInstitute of Geological Science Mineral Assessment Reports

No. 015 The sand and gravel resources of the country around Newton on Trent, Lincolnshire. Description of 1:25 000 resource sheet SK87. 1975

No 017 The sand and gravel resources of the country around Besthorpe,

Nottinghamshire. Description of 1:25 000 resource sheet SK86 and part of SK76. 1975

No 019 The sand and gravel resources of the country south of Gainsborough,

Lincolnshire. Description of 1:25 000 resource sheet SK88 and part of

SK78. 1976

No 020 The sand and gravel resources of the country east of Newark upon Trent, Nottinghamshire. Description of 1:25 000 resource sheet SK85. 1976

No 027 The sand and gravel resources of the country west and south of Lincoln,

Lincolnshire. Description of 1:25 000 resource sheets SK95, SK96 andSK97. 1977

No 029 The sand and gravel resources of the country south-west of Scunthorpe, Humberside. Description of 1:25 000 resource sheet SE80. 1977

No 033 The sand and gravel resources of the country north of Gainsborough, Lincolnshire. Description of 1:25 000 resource sheet SK79. 1978

No 043 The sand and gravel resources of the country around Misterton, Nottinghamshire. Description of 1:25 000 resource sheet SK79. 1979

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No 080 The sand and gravel resources of the country between Stamford andPeterborough. Description of 1:25 000 resource sheets TF00 and TF10. 1981

No 093 The sand and gravel resources of the country around Whittlesey, Cambridgeshire. Description of 1:250 000 sheets TF20 and TL 29. 1982

No 094 The sand and gravel resources of the country north and west of WoodhallSpa, Lincolnshire. Description of 1:25 000 resource sheet TF 16 and part of TF 17. 1972

No 096 The sand and gravel resources of the country around Potter Harworthand Reepham, Lincolnshire. Description of 1:25000 sheets TF06 and 07. 1982

No100 The sand and gravel resources of the country around Billinghay,Lincolnshire. Description of 1:25 000 sheets TF 15 and part of TF 05. 1982

No 108 The sand and gravel resources of the country south of Horncastle,Lincolnshire. Description of 1:25 000 resource sheet TF 26. 1982

No 128 The sand and gravel resources of the country around Coningsby,Lincolnshire. Description of 1:25 000 sheet TF25. 1982

No 130 The sand and gravel resources of the country between Bourne andCrowland, Lincolnshire. Description of 1:25 000 sheet TF 11 and parts of01 and 21. 1982