P/2014/00830 Received 27/06/2014 SOIL RESOURCES AND AGRICULTURAL USE & QUALITY OF LAND AT ROLLESTON PARK FARM TUTBURY, STAFFORDSHIRE Report 953/1 28 th May, 2014
SOIL RESOURCES AND AGRICULTURAL USE & QUALITY OF LAND AT ROLLESTON PARK FARM, TUTBURY, STAFFORDSHIRE F.W Heaven BSc, MISoilSci Report 953/1 Ltd Lockington Hall, Lockington, Derby DE74 2RH 28 th May, 2014
SUMMARY A study and survey of 35.6 ha of land off at Rolleston Park Farm near Tutbury in Staffordshire has shown that most soils have heavy textured topsoils with slowly permeable reddish clay below. The majority of the land is of moderate agricultural quality in sub-grade 3b, while a small amount is best and most versatile land in subgrade 3a. Apart from small areas occupied by inverter, transformer and switchgear cabinets, and access roadways, the only impacts on soils will be the insertion of support legs for the solar panels and temporary surface compaction of soils during equipment installation. The unoccupied ground between rows of panels and under the panels is typically seeded to grassland, which can be grazed by sheep following the completion of installation. The land will be capable of returning to almost unchanged agricultural quality and use after the typical 25 year life of a solar park installation. 1
1.0 Introduction 1.1 This report provides information on the soil resources and agricultural quality and use of an area of 35.6 ha of land on Rolleston Park Farm to the south of Tutbury in Staffordshire. The land is proposed for a solar farm. The report is based on a soil and agricultural desk study, and a survey of the land in May 2014. SITE ENVIRONMENT 1.2 The land investigated comprises parts of three arable fields bordered in the east by Burton Road (A 511). The other margins are marked by field boundaries. The land slopes gradually from a high point at 85 m AOD in the centre of the site to about 65 m AOD in the south east. AGRICULTURAL USE 1.3 The land is used for arable cropping and was in oilseed rape and winter wheat at the time of the survey. It is subject to an Entry Level plus Higher Level Stewardship agreement based on Rolleston Park Farm and covering 174 ha in total. PUBLISHED INFORMATION 1.4 The 1:50,000 BGS geological information shows that the basal geology is Triassic Mercian Mudstone with a very small area of glaciofluvial drift in the north-east of the site. 1.5 The National Soil Map 1 shows most of the land in Worcester soil association, comprising reddish slowly permeable clay soils over mudstone, associated with some fine loamy over clayey soils. 1.6 Reconnaissance agricultural land classification (ALC) mapping carried out in the 1970s shows most of the western half of the study area as grade 2 land, and the eastern edge as grade 3. No more recent studies have been published. 1 Ragg, J M (et al) 1984. Soils and their Use in Midland and Western England Soil Survey of England and Wales Bulletin No. 12 2
2.0 Soils 2.1 The National Planning Policy Guidance states that the planning system should protect and enhance valued soils and prevent the adverse effects of unacceptable levels of pollution. This is because soil is an essential finite resource that provides important ecosystem services, for example as a growing medium for food, timber and other crops, as a store for carbon and water, as a reservoir of biodiversity and as a buffer against pollution. 2.2 A detailed soil resource and agricultural quality survey was carried out in May 2014. It was based on observations at intersects of a 100 m grid, giving a sampling density of one observation per hectare. During the survey soils were examined by a combination of pits and augerings to a maximum depth of 1.2 m. A log of the sampling points and a map (Map 3) showing their location is in an appendix to this report. 2.3 The survey identified slowly permeable soils, most with heavy topsoils over reddish clay subsoils, and some with loamy upper layers over clay subsoils. Heavy soils over reddish clay 2.4 The topsoil is heavy clay loam or clay and has up to 5% rounded quartzite stones, the result of a thin drift cover over the reddish mudstone. The upper subsoil is either reddish clay with faint brown mottling, or slightly stony heavy clay loam where the drift is locally thicker. Where present these upper subsoils overlie slowly permeable reddish clay, passing downwards to reddish brown mudstone. 2.5 An example profile in bare ground from close to observation 32 (Map 3) is described below. 0-27 cm Dark brown (7.5YR 3/3) clay; 4% medium and small rounded quartzite stones; moderately developed coarse angular blocky structure; firm; 5% fine and medium pores; a few very fine fibrous roots; abrupt smooth boundary to: 27-38 cm Yellowish red (5YR 4/6) clay with many yellowish red (5YR 5/8) mottles and a few grey (5YR 5/1) mottles; a few small rounded quartzite stones; moderately developed coarse subangular blocky structure; firm; 3% fine macropores; no visible roots; clear smooth boundary to: 38-70 cm Reddish brown (5YR 4/4) with light greenish grey (5BG 7/1) stoneless clay with common yellowish red (5YR 5/8) mottles; moderately developed coarse prismatic structure becoming structureless, massive below; firm; 0.1% fine pores; a few fine fibrous dead roots; merging boundary to. 70+ cm Dark red (2.5YR 3/6) soft mudstone. Loamier soils over clay 3
2.6 On a hilltop in the east of the site, and in a minor valley in the south, the soils have loamier topsoils and upper subsoils. The topsoil is sandy clay loam and has up to 5% rounded quartzite stones, and the upper the upper subsoil is greyish sandy clay loam with ochreous mottles, also slightly stony. At 50 cm and below the lower subsoil is slowly permeable reddish clay passing downwards to soft mudstone. 2.7 An example profile in a bare wheeling close to observation 33 (Map 3) is described below. 0-31 cm Dark brown (10YR 3/3) sandy clay loam; 4% medium and small rounded quartzite stones; weakly developed coarse angular blocky breaking to moderately developed medium and fine subangular blocky structure; friable; 3% mainly medium pores; common fine fibrous roots; abrupt smooth boundary to: 31-52 cm Light brownish grey sandy clay loam with many fine strong brown (7.5YR 5/8) mottles; 2% small and medium rounded quartzite stones; weakly developed medium angular blocky structure; friable; 5% fine macropores; common fine fibrous roots; clear smooth boundary to: 52-90+ cm Reddish brown (5YR 4/6) stoneless clay with common reddish grey (5YR 5/2) and strong brown (7.5YR 5/8) mottles; structureless, massive; firm; 0.1% fine pores; a few fine fibrous roots. 2.8 Locally the loamy layers are deep and may pass to sandstone. 2.9 Both soil types are slowly permeable and suffer seasonal waterlogging (wetness class III and IV) due to water ponding over the clay subsoils. They support a limited range of food and fibre production, being limited to autumn sown arable crops and grass, and they have a poor capacity to absorb excess winter rainfall which tends to run off. They provide moist, neutral habitats for plant communities. 2.10 The distribution of the soil types is shown on Map 1. 4
3.0 Agricultural Quality 3.1 To assist in assessing land quality, the Ministry of Agriculture, Fisheries and Food (MAFF) developed a method for classifying agricultural land by grade according to the extent to which physical or chemical characteristics impose long-term limitations on agricultural use for food production. The MAFF Agricultural Land Classification (ALC) system classifies land into five grades numbered 1 to 5, with grade 3 divided into two sub-grades (3a and 3b). The system was devised and introduced in the 1960s and revised in 1988. 3.2 The agricultural climate is an important factor in assessing the agricultural quality of land and has been calculated using the Climatological Data for Agricultural Land Classification 2. The relevant site data for an average elevation of 75 m is given below. Average annual rainfall: January-June accumulated temperature >0 C Field capacity period (when the soils are fully replete with water) Summer moisture deficits for: 686 mm 1381 day 157 days mid Nov early April wheat: 99 mm potatoes: 88 mm 3.3 The survey described in the previous section was used in conjunction with the agroclimatic data above to classify the site using the revised guidelines for agricultural land classification issued in 1988 by the Ministry of Agriculture, Fisheries and Food 3. SURVEY RESULTS 3.4 The agricultural quality of the survey area is determined by the degree of soil wetness over slowly permeable subsoils. Land of grade 3 agricultural quality exists on the site. Grade 3a 3.5 There are 4.3 hectares of grade 3a land where the loamier soils similar to those described in paragraph 2.6 drain somewhat better such that they suffer only 2 Climatological Data for Agricultural Land Classification. Meteorological Office, 1989 3 Agricultural Land Classification for England and Wales: Guidelines and Criteria for Grading the Quality of Agricultural Land. MAFF, 1988. 5
moderate seasonal wetness (wetness class III), and the sandy clay loam topsoils are more easily workable. Sub-grade 3b 3.6 This is the dominant land grade on the site accounting for 86% of the agricultural land with soils similar to those described in paragraph 2.3. Long term seasonal wetness caused by water ponding over the slowly permeable layers (wetness class IV) limits workability in autumn and spring. Grade areas 3.7 The boundaries between the different grades of land are shown on Map 2 and the areas occupied by each are shown below. Table 1. Areas occupied by the different land grades Grade/sub-grade Area (ha) % of agricultural land Sub-grade 3a 4.3 14 Sub-grade 3b 31.3 86 Total 35.6 100 6
4.0 Soil resources and their use 4.1 As part of the Government s Safeguarding our Soils Strategy, Defra published a code of practice on the sustainable use of soils on construction sites, which can be helpful in design of developments and setting planning conditions. An Environment Agency strategy Soil a Precious Resource: Our strategy for protecting, managing and restoring soil (Environment Agency, 2007) has complementary aims. 4.2 The proposed development will involve the installation of rows of interconnected photo-voltaic (PV) panels mounted on a steel supporting structure that is driven directly into the ground to a depth of 1 m, with no need for foundations. A typical installation also includes 10 m long, 2.5 m wide and 3 m high inverter cabinets, adjacent transformers and a switchgear cabinet to connect the solar park to the distribution network. 4.3 Apart from small areas occupied by these and access roadways the only impacts on soils will be the insertion of support legs for the solar panels and possible surface compaction of soils during equipment installation. Topsoil 4.4 Topsoil stripped from the route of access tracks or where transformers or substations are to be built should be spread thinly on adjacent land. Subsoil 4.5 Subsoils are easily damaged by trafficking by vehicles used for installation. If compacted during construction work they should be loosened in order to retain their ability to absorb direct rainfall and run-off from the panels. Soil Handling 4.6 The Construction Code of Practice for Sustainable Use of Soils on Construction Sites (Defra 2009) provides guidance on good practice in soil handling. 7
5.0 Conclusions 5.1 The survey shows that most soils have heavy textured topsoils with slowly permeable reddish clay below. 5.2 The majority of the land is of moderate agricultural quality in sub-grade 3b, while a small amount is best and most versatile land in sub-grade 3a. 5.3 Apart from small areas occupied by inverter, transformer and switchgear cabinets, and access roadways, the only impacts on soils will be the insertion of support legs for the solar panels and temporary surface compaction of soils during equipment installation. The unoccupied ground between rows of panels and under the panels is typically seeded to grassland, which can be grazed by sheep following the completion of installation. The land will be capable of returning to almost unchanged agricultural quality and use after the typical 25 year life of a solar park installation. 8
APPENDIX MAPS AND DETAILS OF OBSERVATIONS 9
Land at Rolleston Park Farm, Tutbury: ALC and soil resources survey May 2014 - Details of observations at each sampling point Obs Topsoil Upper subsoil Lower subsoil Slope Wetness Agricultural quality No Depth Texture Stones Depth Texture Mottling Depth Texture Mottling ( ) Class Grade Main limitation (cm) (%) (cm) (cm) 1 0-30 HCL-C 2 30-40 gy C xxx 40-80+ r C xx 1 IV 3b W 2 0-30 HCL-C 2 30-50 r C xx 50-80+ soft mudstone 2 iii/iv 3b w 3 0-30 HCL-C 2 30-90 r C xx 90-110 soft mudstone 1 III/IV 3b W 4 0-30 C 2 30-50 st HCL xxx 50-100+ r C xx <1 III 3b W 5 0-30 HCL 2 30-45 gy C xxx 45-80+ r C xx 1 IV 3b W 6 0-30 C 1 30-60 r C xxx 60-80+ soft mudstone 1 IV 3b W 7 0-30 C 1 30-40 gy C xxx 40-80+ r C xx 1 IV 3b W 8 0-30 C 2 30-50 gy = r C xxx 50-70 soft mudstone 1 IV 3b W 70+ stopped on hard 9 0-30 C 2 30-60 r C xx 60-100 soft mudstone 1 IIII 3b W 10 0-30 HCL 4 30-45 st HCL xxx 45-100+ r C xx <1 III 3b W 11 0-30 HCL 3 30-50 gy + r C xxx 50-80 r C xxx 2 IV 3b W 80-100+ soft mudstone 12 0-30 SCL 3 30-60 SCL xxx 60-80 HCL-SCL xx 1 II 2/3a W 80+ stopped on sandstone? 13 0-30 HCL 2 30-70 r C xxx 70+ soft mudstone <1 IV 3b W 14 0-30 HCL 2 30-55 gy C xxx 55-90+ r C xx 2 IV 3b W 15 0-30 HCL 2 30-70 r C xx 70+ soft mudstone 2 III 3b W 16 0-30 HCL-C 2 30-50 r C xxx 50-80+ soft mudstone 1 IV 3b W 17 0-35 HCL 2 35-65 r C x 65-110 soft mudstone 2 III 3b W 18 0-30 HCL 3 30-50 gy+r C xxx 50-70 r C xx 2 IV 3b W 70+ soft mudstone 19 0-30 HCL-C 3 30-100 r C xx 1 III 3b W 20 0-30 SCL 4 30-95 SCL xx 95-110 r C xx 1 II 2 W 21 0-40 C 2 40-80+ r C xx 3 III 3b W 22 0-30 C 1 30-60 r C x 60+ soft mudstone 0 III 3b W 23 23 0-30 HCL 3 30-70 r C x 70+ soft mudstone 1 III 3b W 24 0-30 HCL 4 30-45 st HCL xxx 45-110 r C xx(x) <1 III 3b W 25 0-30 HCL. 30-50 r C xx(x) 50-110 r GCK xxx 1 IV 3b W 26 0-30 HCL-MCL 3 30-50 HCL xxx 50-110 r C xx 2 III 3a/B W 27 0-30 HCL 3 30-45 HCL xxx 45-100+ r C xx 1 III 3b W 28 0-30 HCL 2 30-70 RC xx 70+ soft mudstone 3 III 3b W 29 0-30 C 2 30-80+ r C xx 3 IV 3b W 30 0-30 HCL 4 30-50 HCL xx(x) 50-110 r C xx 2 III 3b W 31 0-30 HCL 4 30-50 HCL xxx 50-110 r C xx <1 III 3b W 32 0-28 C 4 28-50 r C xx 50-110 soft mudstone 2 III 3b W
Obs Topsoil Upper subsoil Lower subsoil Slope Wetness Agricultural quality No Depth Texture Stones Depth Texture Mottling Depth Texture Mottling ( ) Class Grade Main limitation (cm) (%) (cm) (cm) 33 0-30 SCL 2 30-52 SCL-GCL xxx 52-110 r C xx 1 III 3a W 34 0-30 SCL 2 30-45 SCL xxx 45+ stopped on sandstone? 1 III 3a W 35 0-30 HCL-C 4 30-50 gy HCL xxx 50-70 gy C xxx 2 III 3b W 70-110 r C xx 36 0-28 SCL 2 28-40 SCL xxx 70-90 SC-SCL xxx 2 IV 3b W 40-70 r C xx 90-110 r r+gy C xxx 2 37 0-30 HCL 8 30-60 gy C xxx 60-110 gy C xxxx <1 IV 3b W Key to table Mottle intensity: Texture: Limitations: o unmottled C - clay W - wetness/workability x few to common rusty root mottles (topsoils) ZC - silty clay D - droughtiness or a few ochreous mottles (subsoils) SC - sandy clay De - depth xx common to many ochreous mottles and/or dull structure faces CL - clay loam (H-heavy, M-medium) St stoniness xxx common to many greyish or pale mottles (gleyed horizon) ZCL - silty clay loam (H-heavy, M-medium) Sl slope xxxx dominantly grey, often with some ochreous mottles (gleyed horizon) SCL - sandy clay loam F - flooding SZL - sandy silt loam (F-fine, M-medium, C-coarse) T topography/microrelief SL - sandy loam (F-fine, M-medium, C-coarse) LS - loamy sand (F-fine, M-medium, C-coarse) Texture suffixes & prefixes: S - sand (F-fine, M-medium, C-coarse) ca calcareous: x-extremely, v-very, sl-slightly P - peat (H-humified, SF-semi-fibrous, F-fibrous) (ca) marginally calcareous LP - loamy peat; PL - peaty loam st stony;,v st very stony; a depth underlined (e.g. 50) indicates the top of a slowly permeable layer rb reddish brown, yb yellowish brownish, r - reddish
KEY Survey area Reddish slowly permeable soils over mudstone Soils with loamy upper layers over red clay Client: Project: Land at Rolleston Park Farm Tutbury Map title: Map 1 Main soil types 0 50 metres 100 Lockington Hall Lockington, Derby DE74 2RH Tel: 01509 670570 Scale: 1:5,000 at A4 Date: 16/5/2014
KEY Survey area Sub-grade 3a Sub-grade 3b Client: Project: Land at Rolleston Park Farm Tutbury Map title: Map 2 Agricultural Land Quality 0 50 metres 100 Lockington Hall Lockington, Derby DE74 2RH Tel: 01509 670570 Scale: 1:5,000 at A4 Date: 16/5/2014
KEY Survey area 1 2 3 4 Auger observation 5 6 7 8 9 10 11 12 Soil decription pit 13 14 15 16 17 18 19 20 Client: 21 22 23 24 25 26 27 Project: Land at Rolleston Park Farm Tutbury 28 29 30 31 Map title: Map 3 Location of the Observations 32 33 34 0 50 metres 100 35 36 37 Lockington Hall Lockington, Derby DE74 2RH Tel: 01509 670570 Scale: 1:5,000 at A4 Date: 16/5/2014