Brighton and Hove Wastewater Treatment Project Infrastructure WSI
APPENDIX 1: 2006 GEOTECHNICAL INVESTIGATION RESULTS
(ARCHAEOSCAPE)
An Evaluation of Geotechnical Borehole and Test Pit Data from Locations between Brighton and Peacehaven, East Sussex
C.P. Green, ArchaeoScape, Department of Geography, Royal Holloway University of London, Egham Hill, Egham, Surrey, TW20 OEX, UK
Introduction
A1.1 This report summarises the findings arising from an evaluation of forty-seven geotechnical borehole and test pit logs taken at the site of a proposed waste water treatment works (WTW/SRC) at Peacehaven and along the route of the associated infrastructure between Brighton and Peacehaven. This infrastructure comprises a tunnelled pipeline from Black Rock (Brighton), following the coast to the existing Headworks at Portobello, then across to the WTW/SRC site at Peacehaven. Along the length of the pipeline are a number of components, comprising shafts and two pumping stations. The geotechnical work was conducted by Soil Mechanics Ltd on behalf of Mott Macdonald. The geotechnical data were subsequently collated and evaluated by ArchaeoScape (on behalf of RPS) with the aim of providing an indication of the range of sub-surface conditions likely to be encountered along the pipeline route and at the WTW/SRC site. The Report is divided into two Parts. Part I provides a description and interpretation of the sediments and sub-surface conditions recorded in the boreholes and test pits. Part II lists the components of the scheme and evaluates the ground conditions and geo-archaeological potential at each component location.
Part I
Methods
A1.2 Forty-seven geotechnical sediment logs located between Brighton and Peacehaven, and at the site of the waste water treatment works at Peacehaven, form the basis of this evaluation. The geotechnical logs consist of 29 rotary and 6 cable percussion boreholes, and 12 test pits. Figure 1 displays a summary of the rotary boreholes
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(scale, m OD); to emphasise the locations of the rotary boreholes, vertical lines have been used to differentiate three spatial groups (Brighton, Roedean-Telscombe and Peacehaven). Figure 2 displays a summary of the cable percussion boreholes (scale, m OD), while Figure 3 displays a summary of the test pits (scale, m OD). Along the top of each figure are the borehole or test pit reference numbers and in the case of the rotary boreholes (Figure 1) a code indicating the broad topographic character of the borehole site. A key to this coding system is shown at the bottom of Figure 1. In some cases a second code indicating the driller's log or truncation of the sequence is shown, this is also indicated in the key. The location of the dry valleys as recognised by Mortimore (1997) and components of the scheme as described in Part II are illustrated in Figure 4. Figure 5 shows the locations of the boreholes and test pits along the route of the pipeline.
Rotary Boreholes
A1.3 Twelve rotary boreholes were situated in the eastern suburbs of Brighton (MTR 101A, 101B, 101AA, 101BA, 103A, 103B, 103AA, MBR106, MBR107, MBR108, MTRXC1, MTRXC2) and a further eight along the proposed route between Roedean and Telscombe (MTR 106, MTR 112, MTR118, MTR128, MTR132, MTR134, MTR135, MTR135A). All the other rotary boreholes were within or very close to the site of the WTW/SRC works. The rotary boreholes extend to depths between 25 and 60 metres and in almost all cases terminate in undisturbed chalk of Grade B2 or B1. They provide a good record of weathering and disturbance in the upper part of the chalk and of sediments overlying the chalk. However, sediment recovery was not continuous and gaps in the cores of up to 2m are recorded and may affect the detailed interpretation of contacts between sediment units. The upper 25m of five of the rotary boreholes were not recorded in detail (driller's descriptions only).
Cable Percussion Boreholes
A1.4 The cable percussion boreholes were all put down in the Peacehaven area. The cable percussion boreholes are shallower (15m and in one case 20m) and provide a less refined record of the sediments recovered than the rotary boreholes.
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Test Pits
A1.5 All the test pits were put down in the Peacehaven area within or very close to the site of the treatment works. The test pits were all put down to a depth of 5m.
Results of the Geotechnical Boreholes and Test Pit Logs
A1.6 From an evaluation of the borehole and test pit logs, thirteen sediment types can be identified and possible depositional origins can be suggested as shown in section A1.7 below.
A1.7 The following is a list of sediment types identified from the borehole and test pit logs (Unit Number; Unit Name; Unit Description):
0; Made Ground
1; Topsoil; Brown to dark brown sandy clay with fine to coarse angular to sub- angular flint clasts, penetrated by many modern roots
2; Flinty Head; Comprising of colluvial deposit of brown to dark brown more or less sandy clay with fine to coarse angular to sub-angular flint clasts
3; Chalky Head; Colluvial deposit of brown more or less sandy clay with fine to coarse angular to sub-angular flint clasts and sub-angular to sub-round clasts of weathered chalk
4; Sandy Head; Colluvial deposit of brown to dark brown sandy clay
5; Flint Gravel; Water-laid deposit of fine to coarse angular to sub-round flint clasts
6; Solution pipe infill; Variable mixture of sandy and stony clay, infilling larger solution features in chalk
7; Woolwich Beds; Palaeocene sand and sandstone overlying Chalk; sometimes iron cemented
8; Disturbed/displaced chalk(Chalk grades Dc and Dm); Structureless mass of abraded chalk gravel, sand and silt, often stained orange or yellow mixed
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with variable amounts of angular to sub-angular flint (and occasionally sandstone - probably sarsen), light brown silty loam and brown or dark brown sandy clays. This unit probably includes both colluvial Combe Rock deposits and chalk severely disturbed by periglacial processes and mixed with overlying Tertiary and Quaternary sediments
9; Weathered chalk(Chalk grades C5, B5, B4); Chalk, often stained orange or yellow, retaining its original structure, but often with open joints infilled with silty chalk or silt, clay or sand derived from overlying Tertiary or Quaternary sediments; or small solution features with similar infills
10; Sound chalk(Grades B3, B2 and B1); Chalk, slightly weathered and unweathered in situ chalk
11; Chalk with flints; Driller's description
12; Beach shingle; Includes both the Pleistocene Black Rock Raised Beach and Recent beach shingle
Interpretation of the Geotechnical Boreholes and Test Pit Logs
A1.8 Rotary Boreholes: The sequences recorded from the rotary boreholes provide the most reliable record of sub- surface conditions. These sequences fall into three broad types, as indicated below:
A1.9 Characteristics of Type A, B and C:
A - Sound chalk (Grades B3, B2 or B1) overlain by less than 5m of disturbed/displaced and weathered chalk and/or Quaternary sediments
B - Sound chalk (Grades B3, B2 and B1) overlain by more than 5m of disturbed/displaced chalk and/or Quaternary sediments
C - Sound chalk (Grades B3, B2 and B1) underlying Woolwich Beds sands and sandstone
A1.10 On this basis, the rotary boreholes have been assigned as either Type A, Type B or Type C as discussed below.
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Type A
A1.11 The Type A group includes MBR106, MBR107, MBR108, MTR101A, MTR101B, MTR103A, MTR103B, MTR128, MTR134, MTR135, MPR100C and MPR102. These boreholes can be divided into three sub-groups.
A.i This sub-group includes two low-level boreholes (MBR106 and MBR107) put down on the foreshore in the Black Rock area from ground surfaces below 6m OD. MBR 107 passed through Made Ground down to 3.81m OD and directly into sound chalk (Grade B3). MBR106 passed through Made Ground down to 2.86m OD. Below this level core recovery was incomplete but sediment logged as 'raised beach' was encountered intermittently between 2.26m and 0.76m OD and the borehole reached sound chalk (Grade B3) at 0.26m OD. The interpretation of deposits in borehole MBR 106 as 'raised beach' is accepted in the Interpretative Report prepared by Mott MacDonald (2005). However, the beach deposits recorded in borehole MBR106 almost certainly represent the modern beach, buried during the construction of the marina. At levels between 0.76m and 2.26m OD, they are some 5.6m below the lowest level at which the base of the Black Rock Raised Beach has ever previously been recorded (Hutchinson and Millar 1998 - see discussion of boreholes MTRXC1 and MTRXC2 below). The possibility that these deposits represent the Black Rock Raised Beach can therefore be discounted.
A.ii Borehole MTR128 was located near the axis of a dry valley that reaches the coast at Saltdean (DV4 of Mortimore 1997). This is the longest of the dry valleys reaching the coast between Newhaven and Brighton and is cut down closer to the present sea level than the shorter and more severely truncated valleys (Figure 4). The borehole passed through 4.01m of Made Ground to reach sound chalk (Grade B3) at a depth of only 4.45m (10.51m OD). This result is somewhat unexpected as Mortimore (1997) states that 15m of weathered chalk underlies the dry valley here. It seems possible therefore that the zone of deeply weathered chalk beneath this dry valley is relatively narrow, possibly truncated by the downcutting of the valley, and that the borehole lies outside this zone of deep weathering.
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A.iii The remaining nine boreholes in this group are located on spur summits or on the flanks of dry valleys and record an average depth to sound chalk (Grade B3) of 3.61m.
Type B
A1.12 The Type B group includes MTRXC1, MTRXC2, MTR106, MTR112, MTR118, MTR132, MTR135A, MPR104, MPR110, MPR109 and MPR112. This group includes two boreholes (MTRXC1, MTRXC2 - sub-group B.i, below) put down through the thick sequence of periglacial slope deposits that overlies the Black Rock Raised Beach. All the other boreholes are situated in dry valleys and fall into two sub-groups (B.ii and B.iii, below).
B.i Boreholes MTRXC1 and MTRXC2 - These two boreholes provide important insights into the distribution and elevation of the Black Rock Raised Beach. They are located in the Black Rock area of Brighton, just south of Marine Drive, close to the point where this road is joined from the north by Marina Way. They are about 20m inland from the top of the cliff in which sediments associated with the Black Rock Raised Beach remain visible and towards the western end of the cliff exposure. They are therefore close to the point where the fossil cliff line, inferred by Smith (1936) and Pope (no date), turns sharply northward away from the present shoreline. Borehole MTRXC1 was close to the line delineated by Smith, on its seaward side; MTRXC2 was some 15-20m further west. These were placed away from the line of the proposed tunnel to determine the potential for contamination from the gasworks site to the north.
A1.13 Borehole MTRXC1 was put down from a ground level of 25.78m OD. Sound chalk (Grade B3) was first recorded at 9.58m OD, but above this level, core recovery was repeatedly interrupted. From the ground surface downward the borehole passed through at least 3.5m of Made Ground into chalky rubble (recorded as Upper Chalk Grade V, Dc) with occasional pieces of sandstone (?sarsen). This material was present down to 11.14m OD. Just above this level, between 11.68m OD and 11.34m OD the log records 'rounded' medium to coarse sized flints. No core was recovered between 11.14m OD and the sound chalk at 9.58m OD.
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A1.14 Borehole MTRXC2 was put down from a ground level of 24.87m OD. Sound chalk (Grade B3) was first recorded at 4.47m OD. Core recovery above this level was repeatedly interrupted. From the ground surface downward the borehole passed through deposits recorded as Head down to 12.97m OD. Below this level the sediment is described as Upper Chalk Grade V, Dc down to 9.47m OD. At this level the log records "No recovery due to flints (driller's description)". Between 8.52m OD and 6.67m OD there was intermittent recovery of 'subangular to rounded coarse occasional medium gravel sized flint' passing down to 'subangular to rounded coarse occasional medium predominantly coarse gravel sized flint'. This gravel seems likely to represent the Black Rock Raised Beach, first encountered at 9.47m OD, with the beach deposits extending down to 6.67m OD. No core was recovered between 6.67m OD and the sound chalk at 4.47m OD.
A1.15 The height range within which the probable beach deposits were recorded in borehole MTRXC2, compare closely with historical records of the position of the beach (Hutchinson and Millar 1998). From an examination of these records, Hutchinson and Millar derive the following data. They emphasise that none of the historical records were based on instrumental survey:
Top of beach deposits 10.67-12.30m OD
Base of beach deposits 7.89 - 9.14m OD
Wave-cut platform 6.71 - 8.88m OD
A1.16 Thus the level of the probable beach material in borehole MTRXC2 (6.67 - 9.47m OD) is consistent with a position on the wave cut platform at a short distance from the cliff foot. The level of possible beach cobbles in borehole MTRXC1 (11.4 - 11.18m OD) is consistent with a position very close to the cliff foot where the beach is likely to have been piled up against the cliff. The very chalky nature of the overlying rubble is also consistent with a position close to the cliff foot.
B.ii Boreholes in the short dry valleys that terminate southward at the coast (MTR106, MTR112, MTR118, MTR132 and MTR135A). The sediments and chalk underlying the floors of these valleys are in several cases well exposed at the coast and have been illustrated and described by Mortimore (1997) as shown in Figure 4. The borehole records confirm the presence
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further inland of sequences closely similar to those exposed at the coast, with an average depth of 10.85m to sound chalk (Grade B3).
B.iii Boreholes in the Upper Piddinghoe Dry Valley in which the proposed site of the waste water treatment works is located (MPR104, MPR110, MPR109 and MPR112). Two of these boreholes (MPR104 and MPR109) were located close to the axis of the dry-valley and immediately adjacent to shallow boreholes (respectively boreholes 31 and 62) put down during the ArchaeoScape investigation of the site (Swindle et al 2004). The rotary boreholes confirmed the presence of superficial Quaternary deposits underlying the axis of the dry-valley. MPR104 passed through 5.7m of dry- valley infill overlying the Chalk, and MPR109, through 5.4m. The nearby ArchaeoScape boreholes indicated thicknesses of infill in excess of 3.0m. In contrast, MPR110, close to the northern edge of the valley floor, proved only 0.2m of topsoil overlying disturbed/?transported chalk and was situated adjacent to ArchaeoScape boreholes (12 and 22) that recorded similar, shallow soil profiles overlying chalk. Borehole MPR112 is above and to the north of the dry valley floor but records 5.4m of Head overlying disturbed and weathered chalk passing down to sound chalk (B3) at 11.2m. It is immediately alongside a test pit (MPTP113), which records only 1.4m of superficial over weathered chalk, with sound chalk (Grade B3) encountered at only 3.0m. It seems possible therefore that borehole MPR112 penetrated the infill of a solution feature. The average depth to sound chalk (Grade B3) in these four rotary boreholes is 12.69m, slightly greater than in dry valleys draining directly to the coast, possibly reflecting the position of the valley in the upper reaches of the dry valley network where erosion has been less active.
Type C
A1.17 The Type C group includes MTR214, MTR228 and MTR228A. All the boreholes in this group are on high ground (>40m OD) where Lower Tertiary sediments overlie the Chalk.
Unclassified
A1.18 Boreholes MTR101AA, MTR101BA, MTR103AA and MTR118A are marked as unclassified due to lack of detail in the sediment log.
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Cable Percussion Boreholes
A1.19 These boreholes are all situated in the Upper Piddinghoe Dry Valley. They provide a less refined record of sub-surface conditions but confirm the presence of deep (>10m) sequences of disturbed and weathered chalk underlying mainly thin superficial sequences. Four of these boreholes (MPC103, MPC105, MPC106, MPC107) were put down on the edge of the valley floor and recorded between 0.4m and 1.2m of superficial overlying weathered and disturbed chalk. Similar shallow sequences were recorded in nearby boreholes put down during the ArchaeoScape investigation of the site (Swindle et al 2004) (respectively boreholes 3, 1, 14 and 76). Boreholes MPC100C and MPC111 were located closer to the dry-valley axis and recorded deeper sequences, respectively 1.9m and 3.3m of superficial overlying chalk. MPC 100C was situated outside and to the west of the array of ArchaeoScape boreholes. MPC 111 is adjacent to an ArchaeoScape borehole (82) in which over 3.0m of superficial was recorded.
Test Pits
A1.20 The test pits are all in the Upper Piddinghoe Dry Valley. They confirm the findings of the detailed investigation of the sediments (colluvial and stream deposits) overlying the chalk in this area (Green et al 2005) and supplement these findings by showing that the chalk immediately underlying the sediments includes both disturbed and weathered chalk and in some places sound chalk (Grade B3). Five of the Test pits (MPTP104, MPTP109, MPTP113, MPTP114) were located on the lower valley-side slope to the north of the valley floor margin and outside the array of ArchaeoScape boreholes. In four of these pits thin sequences (between 0.12m and 1.4m) of superficial were recorded overlying chalk. In contrast, in MPTP108 a thickness of 4.8m of superficial was recorded although boreholes and test pits nearer to the valley floor recorded much thinner superficial sequences (<1.0m). Test pit MPTP110 was located on the valley floor and recorded 2.1m of superficial over weathered and disturbed chalk. A nearby ArchaeoScape borehole (19) recorded a similar thickness of superficial.
General Summary
A1.21 The borehole and test pit records provide an indication of a range of sub-surface conditions likely to be encountered along the route of the proposed sewer between
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Brighton and Peacehaven and at the site of the treatment works at Peacehaven. They indicate that while reasonably sound chalk (Grade B3 or better) is generally present at depths of less than 5.0m on summit areas and valley sides, the floors of the dry valley may be underlain by a substantial thickness of Head and Combe Rock overlying deeply weathered chalk. The upper part of these superficial layers (up to c.2.0m) may in some cases (as demonstrated in the Upper Piddinghoe Dry Valley) represent Holocene (post-Neolithic) hillwash. Because the good quality rotary borehole logs are widely spaced along much of the proposed route, it is not possible to claim that they are fully representative of the sub-surface conditions. However it can be confidently stated that none of the proposed works, as described, will affect the sediments forming the Black Rock Raised Beach or any of the deposits that overlie the raised beach.
Part II
Site Summaries
A1.22 The following site summaries outline the potential geo-archaeological interest for each of the main components of the scheme. The summaries show the height OD of each locality, list the exploratory boreholes associated with each component and provide representative summary stratigraphic logs based on the borehole records. Boreholes MTR103B, MTR112 and MTR118 have previously been described by Green (2005) and the Rottingdean and Saltdean sites by Swindle et al (2003). The summaries below follow these accounts closely and confirm the observations previously reported. (N.B. The summary logs may be discontinuous due to failed core recovery).
A1.23 Black Rock Penstock Chamber: 5.7m OD (MBR106, MBR107, MTRCX1, MTRCX2)
A1.24 The chamber is located on the wave-cut platform below the cliff face, in an area already much disturbed by modern development, including the existing chamber. The top of the chamber is some 5m-6m below the level of the recorded base of the Black Rock Raised Beach. Should the works extend below the level of the existing structure, it will likely pass through remnants of the modern beach, directly into sound chalk (Grade B3):
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MBR107
0.00-2.90 Made Ground
3.50-5.00 Modern Beach
Below 5.50 Chalk (B3)
No geo-archaeological interest
A1.25 Marine Gate Shaft: 34.1m OD (MTR101B)
A1.26 This shaft lies some 50m inland from the cliff top and about 150m to the east of the point where the fossil cliff-line of the Black Rock Raised Beach intersects the modern cliff-line. A thin layer of head overlies weathered chalk passing down to sound chalk at a depth of less than 5.0m.
MTR101B
0.00-1.61 Soil over chalky Head
1.61-3.38 Weathered Chalk
Below 3.38 Chalk (B3)
Geo-archaeological interest low
A1.27 Marine Drive Roedean Pumping Station: 33.0m OD (MTR103A and MTR103B).
A1.28 This lies some 40m inland from the sea-cliff that exposes in situ chalk. A thin layer of Head and disturbed chalk overlies weathered chalk passing down to sound chalk at a depth of less than 5.0m
MTR103B
0.00-1.26 Made Ground
1.26-1.80 Chalky Head
1.80-4.70 Weathered Chalk
Below 4.70 Chalk (B3)
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Geo-archaeological interest low
A1.29 Roedean Way Shaft: 30.0m OD (MTR106)
A1.30 This shaft is situated about 50m inland from the modern cliff line in a short, truncated dry-valley. A sequence of Head and disturbed/displaced chalk overlies weathered chalk passing down to sound chalk at a depth of 13.95m. Palaeoenvironmental evidence (palaeosols/Mollusca) possible in Head and Combe Rock.
MTR106
0.00-2.90 Made Ground
2.90-6.75 Flinty/Chalky Head and disturbed/displaced chalk
6.75-13.95 Weathered chalk
below 13.95 Chalk (B3)
Geo-archaeological interest low/moderate
A1.31 Ovingdean Shaft: (MTR112) 21.2m OD
A1.32 This shaft lies about 75m inland from the modern cliff line on the floor of a truncated dry valley. The sediments underlying the dry valley are exposed at the coast (DV6 of Mortimore 1997) and are described by Mortimore as 'very strange lobes of sediment' comprising 'khaki coloured silt and sand grade chalky head (metastable, becoming mobile on wetting)' interfingering with flint gravels. Palaeoenvironmental evidence (palaeosols/Mollusca) possible in Head.
MTR112
0.00-1.20 Made Ground
1.20-2.95 Flinty gravel
3.45-8.23 Disturbed/displaced chalk
8.23-11.0 Weathered chalk
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Below 11.0 Chalk (B3)
Geo-archaeological interest low/moderate
A1.33 Rottingdean Shaft: (see Appendix for additional detail) 14.3m OD (MTR118)
A1.34 This shaft lies about 75m inland from the modern beach on the floor of a dry valley (DV 5 of Mortimore 1997) that grades down to within a few metres of present-day sea level. A sequence of Head and disturbed chalk overlies weathered chalk passing down to sound chalk at a depth of 7.90m. Palaeoenvironmental evidence (palaeosols/Mollusca) possible in Head and Combe Rock)
MTR118
0.00-1.20 Made ground
1.20-1.60 Flinty Head
3.60-5.10 Disturbed/displaced chalk
5.10-7.90 Weathered chalk
Below 7.90 Chalk (B3)
Geo-archaeological interest low/moderate
A1.35 Saltdean Shaft: (see Appendix for additional detail) 16.2 OD (MTR128)
A1.36 This shaft lies about 45m inland from the modern beach on the floor of a substantial dry valley (DV4 of Mortimore 1997) that grades down to within a few metres of present-day sea level. Mortimore (1997) records 15m of weathering in the coastal exposure beneath DV4 but in borehole MTR128 a thin sequence of Head and disturbed/displaced chalk rests directly on sound chalk (B3) at a depth of 4.45m.
MTR128
0.00-4.01 Made Ground
4.01-4.45 Chalky Head and disturbed/displaced chalk
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Below 4.45 Chalk (B3)
Geo-archaeological interest low
A1.37 Saltdean East Shaft: 31.4m OD (MTR132)
A1.38 This shaft lies about 65m inland from the modern cliff line and upslope from the floor of a short, severely truncated dry valley - DV3 of Mortimore (1997) who records 15m of weathering in the coastal exposure beneath the dry valley. Borehole MTR132 passed through disturbed/displaced chalk to sound chalk (B2/3) at a depth of 9.60m. Gravelly sediment logged as 'possible solution feature' was recorded within the disturbed/displaced chalk sequence.
MTR132
0.00-0.20 Soil
0.20-2.43 Combe Rock
2.43-6.60 Chalk and flint gravel ('possible solution feature')
6.60-7.35 Sandy clay ('possible solution feature')
7.35-9.60 Disturbed/displaced chalk
Below 9.60 Chalk (B2)
Geo-archaeological interest low
A1.39 Portobello Pumping Station; 27.5m OD (MTR134, MTR135, MTR135A)
A1.40 This pumping station lies about 85m inland from the modern shoreline and upslope from the floor of a short, severely truncated dry valley - DV2 of Mortimore (1997) who describes weathered chalk in the coastal exposure beneath the dry valley, overlain by 'very complex Quaternary sediments', thicker than those observed in DV3 and DV4 and affected by dissolution pipes. In boreholes MTR134 and MTR135 (closely adjacent respectively to the western Reception Shaft and the Pumping Station Shaft) only thin beds of Quaternary sediment are present. However in borehole MTR135A put down less than 50m to the east of MTR135, but closer to the axis of the dry
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valley, and less than 25m from the proposed site of the eastern Reception Shaft, a deeper sequence of disturbed and weathered chalk is present.
MTR135
0.00-0.50 Soil
0.50-2.50 Disturbed/displaced chalk
Below 2.50 Chalk (B3)
Geo-archaeological interest low
MTR135A
0.00-0.10 Made Ground
0.10-1.75 Flinty Head
1.75-5.04 Disturbed/displaced chalk
5.05-12.21 Weathered chalk
Below 12.21 Chalk (B3)
Geo-archaeological interest low/moderate
A1.41 Meridian Car Park Shaft: 42.0m OD (MTR214)
A1.42 This shaft is located inland, on the high ground above and to the south west of the Upper Piddinghoe dry valley. Sandy Palaeocene sediments overlie sound chalk (B3)
MTR214
0.00-0.60 Made Ground
0.60-7.15 Palaeocene sands
Below 7.15 Chalk (B3)
Geo-archaeological interest low
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A1.43 Peacehaven WTW/SRC: 28.0-30.0m OD
A1.44 This site lies in the Upper Piddinghoe Dry Valley. Investigation of the sub-surface geology has been undertaken in six rotary and six cable percussion boreholes, 12 test pits and 116 shallow boreholes. The Quaternary sediments occupying the dry valley, and the shallow sub-surface conditions and geo-archaeological interest of the site have been described by Green et al (2005). Boreholes penetrating to sound chalk (B3) have confirmed the findings of this report and show in addition that the Quaternary sediments on the valley floor are underlain by disturbed (weathered and possibly transported) chalk, whereas, on slopes above the level of the valley floor, sound chalk is present at relatively shallow depths. The presence of solution features preserving deeper sediment sequences has also been noted.
MPR102 (lower valley side)
0.00-0.35 Soil
0.35-1.68 Combe Rock
1.68-4.21 Weathered Chalk
Below 4.21 Chalk (B3)
Geo-archaeological interest moderate/high
MPR109 (valley floor)
0.00-0.30 Soil
0.30-3.40 Flinty Head
4.60-4.90 Disturbed/displaced chalk
4.90-5.40 Flint gravel
5.40-6.10 Disturbed/displaced chalk
6.10-14.4 Weathered Chalk
Below 14.4 Chalk (B3)
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Geo-archaeological interest moderate/high
A1.45 Friars Bay (Head Chamber) Shaft: 55.7m OD (MTR228)
A1.46 This shaft is on the high ground between the Upper Piddinghoe Dry Valley and the coast. Sandy Palaeocene sediments overlie sound chalk (B3).
MTR228
0.00-1.00 Made Ground
1.00-1.34 Sandy Head
1.34-12.45 Palaeocene sands and sandstone
Below 12.45 Chalk (B3)
Conclusion
A1.47 Sub-surface conditions along the proposed route are variable but there is no evidence that deposits of highly significant geo-archaeological interest are present. In particular the proposed works will not impact on the Black Rock Raised Beach or on any of the sediments or buried landforms associated with it. Elsewhere, several of the proposed shafts and adjacent portions of tunnel will be excavated in Quaternary sediments and/or weathered/disturbed chalk where these sub-surface conditions are present underlying the floors of dry valleys. Evidence of palaeoenvironmental interest may be present in these Quaternary deposits in the form of buried soils and plant or faunal remains. In addition the upper part of these superficial sequences may represent Holocene (post-Neolithic) hillwash. However, between Brighton and Peacehaven, where these Quaternary sediments are visible in coastal exposures at no great distance from the main components of the scheme, no buried soils or organic sediments have been recorded. The likelihood of such features coming to light in the excavations is therefore low or low to moderate. In the case of the proposed waste-water treatment works in the Upper Piddinghoe Dry Valley, the geo- archaeological interest has already been established and the findings of the present report confirm this interest and do not alter recommendations that have already been made (Green et al 2005). In the case of the Rottingdean and Saltdean Shafts, the present report confirms in broad terms the findings of the study undertaken by
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ArchaeoScape during an earlier phase of site investigation (Swindle et al 2003 - see Appendix). In this earlier report, no attempt was made to differentiate the grade of chalk encountered in the Rottingdean and Saltdean boreholes, but laboratory examination of samples from the superficial deposits overlying the Chalk and mapped by BGS as Head showed that these deposits include anthropogenic material and in part at least, represent Made Ground as indicated in the borehole logs that form the basis of the present report. Three other sites investigated at this time, Sheepcote Valley on the eastern outskirts of Brighton and Brookside Farm and North Quay, both in Newhaven, were not selected for further investigation and lie outside the area of the scheme in its present form.
References
Green, C.P. 2005 Peacehaven Borehole Logs. Unpublished ArchaeoScape Report, Royal Holloway University of London, Egham.
Green, C.P., Swindle, G.E., Branch, N.P., Palmer, A.P., Vaughan Williams, A., Austin. P. and Keen, D. 2005 A Reconstruction of the Environmental History of a Dry Valley at Peacehaven, East Sussex, UK, Unpublished ArchaeoScape Report, Royal Holloway University of London, Egham.
Hutchinson, J.N. and Millar, D.L. 1998 Survey of the interglacial chalk cliff and associated debris at Black Rock, Brighton. In: Murton, J.B., Whiteman, C.A., Bates, M.R., Bridgland, D.R., Long, A.J., Roberts, M.B. and Waller, M.P. (eds) The Quaternary of Kent and Sussex, Quaternary Research Association Field Guide. London. 135-146.
Mortimore, R.N. 1997 The Chalk of Sussex and Kent, Geologists' Association Guide no. 57. Geologists' Association, London.
Mott MacDonald 2005 Brighton and Hove WWT Scheme. Main Ground Investigation Phase 1. Interpretative Report. Unpublished Report.
Pope, M. no date The Kemp Town Gasworks Site: Background, Geoarchaeological potential and Recommendations for work. Unpublished Report.
Smith, B. 1936 Levels in the raised beach, Black Rock, Brighton. Geological Magazine, 73, 423-426.
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Swindle, G.E., Green, C.P., Branch, N.P. and Gale, R. 2003 Interim Environmental Archaeological Assessment: Proposed Brighton and Hove Waste Water Treatment Works. Unpublished ArchaeoScape Report, Royal Holloway University of London, Egham.
Swindle, G.E., Green, C.P. and Branch, C.P. 2004 A Borehole Survey Within a Dry Valley at Peacehaven, East Sussex, UK, Unpublished ArchaeoScape Report, Royal Holloway University of London, Egham.
Page 34 Depth (m OD) MPC 100C 35 1 MPC 3 105 MPC 8 1 103 1 MPC 8 8 MPC 106 107 30 1 1
8 MPC 107 9 1 25
9 3 9 8 9
20
15 8
10
5
Figure 2: Cable percussion boreholes taken at Peacehaven TP TP TP TP TP 100 108 1 105 113 37 104 1 1 1 36 2 1 2/ TP 2 2 35 3 7 106 8 2 TP 8 34 9 1 TP 8 2 101 33 9 1 TP 109 TP 10 32 9 TP 8 1 114 8 2 102 1 103 1 31 8 8 2 1 30 2 10 TP 29 10 8 110 9 28 1 10 8 27 2 26 9 25 8 24 23 22
Figure 3: Test pits at Peacehaven
Brighton and Hove Wastewater Treatment Project Infrastructure WSI
APPENDIX 1A: INTERIM ENVIRONMENTAL ARCHAEOLOGICAL
ASSESSMENT: PROPOSED BRIGHTON AND HOVE
WASTE WATER TREATMENT WORKS
G.E. Swindle, C.P. Green, N.P. Branch and R. Gale, Department of Geography, Royal Holloway University of London, Egham Hill, Egham, Surrey, TW20 OEX, UK
Introduction
A1a.1 This report summarises the interim findings arising out of the environmental archaeological investigation undertaken by ArchaeoScape in connection with the proposed Brighton and Hove Waste Water Treatment Works (WTW). A series of geotechnical boreholes and trial pits were located along the route of the proposed WTW under the supervision of Mott MacDonald (Figure 1). These geotechnical investigations permitted an examination of the local sediment successions, and thus an opportunity to assess their potential for undertaking detailed environmental archaeological work. In addition, the investigations provided an opportunity to record the presence of any archaeological remains that might enhance our understanding of the cultural history of the study area and provide the basis for detailed archaeological work. The assessment involved: (a) recording the lithostratigraphy in selected boreholes and trial pits; (b) rapid geoarchaeological and bioarchaeological assessment of selected bulk samples from boreholes and trial pits; (c) review of previous palaeoenvironmental (including environmental archaeological) work for the study area; (d) assessment of geotechnical data produced by Mott Macdonald for the study area, and (e) making recommendations for further work.
Methods
A1a.2 The lithostratigraphy was recorded using standard procedures outlined in Troels- Smith (1955). This involved noting the physical properties (e.g. colour), composition (e.g. gravel (Gg), sand (Ga), clay (As), silt (Ag), peat (Tl, Th and Tb) and detritus (Dl, Dh and Dg)), the degree of peat humification (humo) and inclusions (such as archaeological artefacts).
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Site Records
A1a.3 Boreholes and trial pits were monitored and the lithostratigraphy recorded in five separate locations along the route of the proposed WTW: Rottingdean, Saltdean, Sheepcote, North Quay and Brookside Farm (Figure 1). The results are presented below.
Rottingdean
A1a.4 The borehole location is at the junction of Rottingdean High Street (road B2123) and West Street (National Grid Reference (NGR): TQ 369 022).Rottingdean High Street is aligned along the floor of a dry valley that drains from the north and reaches the coast c. 160m to the SE of the borehole site, forming a gap in the low cliffs that rise here to levels between 15m and 20m OD, and overlook the foreshore and undercliff walk in the immediate vicinity of Rottingdean (Mott Macdonald, 2003a). The borehole (BH501) is on the floor of the dry valley (Figure 1). The bedrock is the Upper Chalk, but the floor of the dry valley is mapped by the Geological Survey (1:50,000 Sheet 318/333 Brighton and Hove - 1984) as Head (undifferentiated chalk and flint rubble locally decalcified).
A1a.5 The borehole passed through 2.0m of undifferentiated chalky gravel above the in situ weathered Chalk (Figure 2). Three bulk samples (1.0-1.5m; 1.2-1.5m; 1.5-2.0m) of the superficial material were randomly selected and wet sieved to obtain >4.0mm and 1-4mm residues. These residues were examined using a low-power binocular microscope with the aim of recording the presence of bioarchaeological remains and artefacts (Table 1). All the samples contained particles of coal and/or brick, and the 1-4mm samples contained small quantities of charcoal. The >4mm fraction of the 1.5- 2.0m sample contained a single flint flake. No significant organic remains and no unambiguous artefacts were present.
A1a.6 The chalky gravel appeared to be a typical Head (Combe Rock) deposit, characteristically present infilling dry valleys in the Chalk of southern England. Intrusive material (coal, brick, etc) up to c. 5mm can be introduced into such deposits in worm burrows extending to depths of up to 1.5m below the ground surface. The preservation of such material in the >4.0mm fraction at depths between 1.5m and 2.0m suggests that part, at least, of the superficial layer may be made ground, raising the natural surface level by at least 0.5m.
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A1a.7 There is no evidence from the samples taken at Rottingdean of any specific or significant archaeological interest.
Saltdean
A1a.8 This site (NGR: TQ 380 019)is between Saltdean Lido and the A259 road which runs along the sea front at Saltdean. The Lido and adjacent open space occupies the floor of a dry valley that reaches the coast about 40m to the south of the borehole site, forming a gap in the cliff that otherwise overlooks the foreshore in the vicinity of Saltdean and rises here to a level of up to 30m OD (Mott Macdonald, 2003c). The borehole (BH502)is located on the floor of the dry valley (Figure 1). The bedrock is the Upper Chalk, but the floor of the dry valley is mapped by the Geological Survey (1:50,000 Sheet 318/333 Brighton and Hove - 1984) as Head (undifferentiated chalk and flint rubble locally decalcified).
A1a.9 The borehole passed through 2.0m of undifferentiated chalky gravel above the in situ Chalk (Figure 2). Three bulk samples (0.5-1.0m; 1.0-1.5m; 1.5-2.0m) of the superficial material were randomly selected and wet sieved to obtain >4.0mm and 1- 4mm residues. These were examined using a low-power binocular microscope with the aim of recording the presence of bioarchaeological remains and artefacts (Table 2). All the samples contained particles of intrusive material, including coal, glass and slag. Very small amounts of charcoal and a few snail shells were present in the 1- 4mm fraction of the uppermost sample (0.5-1.0m). A single flint flake was present in the >4.0mm fraction of the 1.5-2.0m sample. No significant organic remains and no unambiguous artefacts were present.
A1a.10 The chalky gravel appears to be a typical Head (Combe Rock) deposit, characteristically present infilling dry valleys in the Chalk of southern England. The presence of coal and glass as at depths between 1.5m and 2.0m suggests that part, at least, of the superficial layer may be made ground, raising the natural surface level by at least 0.5m. As at Rottingdean, there is no evidence at Saltdean of any significant archaeological or palaeoenvironmental interest. A more extensive excavation in the sediments occupying the dry valley floor could be expected to yield occasional artefacts and possibly lenses of fine-grained sediment containing molluscan faunas. However, further archaeological or palaeoenvironmental assessment at Saltdean or Rottingdean are not recommended at this stage.
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Sheepcote Valley
A1a.11 Sheepcote valley (NGR: TQ 342 044) lies immediately to the east of the eastern suburb of Brighton (Whitehawk) and is bounded on the east by the East Brighton Golf Course (Figure 1). Sheepcote Valley is a dry valley draining towards the south and reaching the coast between Kemp Town and Black Rock (Mott Macdonald, 2003b). The bedrock geology is the Upper Chalk and the floor of the dry valley is mapped by the Geological Survey (1:50,000 Sheet 318/333 Brighton and Hove - 1984) as Head (undifferentiated chalk and flint rubble locally decalcified). However, the geological map shows much of Sheepcote Valley as Made Ground, reflecting the presence there of a landfill site in use possibly from as early as 1916 to closure in 1979. Chalk spoil from the Brighton Stormwater Tunnel was also placed in Sheepcote Valley between 1994 and 1996. The borehole (BH202)is situated within the landfill site. The borehole passed through 10.6 m of landfill material above the in situ Chalk (Figure 2).
A1a.12 The trial pits (TP 201, 202, 203, 204, 205 and 206), are situated towards the head of the dry valley where it forms a broad, somewhat irregular amphitheatre, rising fairly steeply (1 in 9) to the north. The trial pits are near the axis of the valley and on its eastern flank. Six trial pits (Figure 3), were opened using a JCB 3CX. Four of the pits (TP 201-204) (all the northerly ones) were entirely in landfill debris to their maximum depth. The two remaining trial pits were in undisturbed weathered Chalk (TP 205-206). The exact boundaries of the landfill seem to be somewhat indeterminate, and judging by the trial pit results, irregular in detail, at least on the eastern side of the valley.
A1a.13 Although no significant organic remains or archaeological material were recorded from the trial pits, the discovery of shallow archaeological features on the valley side that may date to the Bronze Age (RPS Consultants, pers. comm.) suggests that further investigation of this locality may be necessary.
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Figure 3: Lithostratigraphy of the Trial Pits at Sheepcote Valley
North Quay
A1a.14 North Quay (NGR: TQ 445 023), lies on the east bank of the River Ouse at a distance of c. 100m from the river and c. 2.25km upstream from its mouth (Figure 1) (Mott Macdonald, 2003e). The bedrock geology here is the Upper Chalk and the floor of the Ouse valley is mapped by the Geological Survey (1:50,000 Sheet 334 Eastbourne - 1971) as alluvium. The borehole (BH301)extended to a depth of 20m in alluvium (Figure 2). The alluvium comprises a sequence of silty and clayey sands that were recorded during the drilling operation from 14 ‘spot’ samples (Table 3). The uppermost sample (2.0m), incorporating gravels and chalk, may be made ground but below this level the samples seem to indicate undisturbed alluvium. No fossil content was recognised in the upper samples (2-5m, at depths between 2.5m and 5.7m) but below this level, Mollusca and plant remains are present in most samples including wood fragments at depths of 15m and 17.5m. The North Quay site includes molluscan faunas that were recorded in abundance and there would therefore be interpretative benefits in pursuing a multidisciplinary approach to the site.
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Table 3: Lithostratigraphy at North Quay (BH301) based on the ‘Spot’ Samples
Depth (m) Description Troels-Smith Colour
2 gravels and chalk in a silty clay matrix As2 Ag1 Gg1 Blue/green
2.5 laminated silty sand with some clay Ga2 Ag1 As1 Blue/green
2.8 silty clay As2 Ag2 Blue/green
4.8 - 5 silty sand Ga2 Ag2 Blue
5.7 silty sand Ga2 Ag2 Blue
7.9 clayey sand + shells As2 Ga2 Blue/green
7.5 - 7.9 clayey sand + flecks of organic material As2 Ga2 Sh+ Green
9 clayey sand + shells As2 Ga2 Greyish blue
9 - 9.5 silty sand Ga2 Ag2 Blue
10 - 10.5 silty clayey sand Ga2 As1 Ag1 Greyish blue
13 silty clayey sand + shells Ga2 As1 Ag1 Greyish blue
15 coarse clayey sand + shells and wood fragments Ga2 As2 Sh+ Green
17.5 coarse clayey sand + shells and wood fragments Ga2 As2 Sh+ Green
19.5 coarse shelly sand Ga4 Green
Brookside Farm
A1a.15 Brookside Farm (NGR: TQ 443 020), lies on the west bank of the River Ouse at a distance of c. 50m from the river and c. 2.0km upstream from its mouth (Figure 1). The bedrock geology here is the Upper Chalk and the floor of the Ouse valley is mapped by the Geological Survey (1:50,000 Sheet 334 Eastbourne - 1971) as alluvium (Mott Macdonald, 2003d). The borehole (BH402) extended to a depth of 32.5m. The upper 30m was in alluvial deposits and the borehole terminated in the Upper Chalk (Figure 2). The alluvial deposits consist largely of silty clay, passing down into silty sand at depths of c. 20-24m, through silty clays to c. 28m and into gravel at the base of the sequence, immediately above the Chalk. The alluvium was
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recorded during the drilling operation from 45 ‘spot’ samples (Table 4). The sediments were organic at several levels, with peat layers at 11.5m, 12-12.5m, 15m and 27.5m, and wood fragments recognisable at 11.5m and 27-27.5m.
A1a.16 Two bulk samples (27 & 27.5m) were randomly selected and wet sieved to obtain >4.0mm and 1-4mm residues. The residues were examined using a low-power binocular microscope to establish the presence of bioarchaeological remains and artefacts. All the samples contained wood and beetle fragments, and the 27.5m sample contained a small amount of Mollusca (Table 5).
Table 4: Lithostratigraphy at Brookside Farm (BH402) based on the ‘spot’
samples
Depth (m) Description Troels-Smith Colour
4.5 - 4.95 silty clay + organic detritus Ag2 As2 Sh+ Orangey brown
5.5 silty clay Ag2 As2 Greenish orange
6 clayey sand As2 Ga2 Greenish blue
6.5 silty sand Ga2 Ag2 Bluish green
7 silty sand Ga2 Ag2 Bluish green
7.5 silty sand Ga2 Ag2 Bluish green
8 silty clay Ag2 As2 Bluish green
8.5 silty sand Ga2 Ag2 Blue
9 clayey silty sand Ga2 Ag1 As1 Greenish blue
9.5 silty clay + organic detritus Ag2 As2 Sh+ Greyish blue
10 silty clay Ag2 As2 Greyish blue
10.5 silty clay Ag2 As2 Greenish blue
11 silty clay Ag2 As2 Greenish blue
silty clay + interbedded peat and large wood 11.5 fragments Ag2 As2 Sh+ Greenish blue
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Depth (m) Description Troels-Smith Colour
12 silty clay Ag2 As2 Greenish blue
12 - 12.5 silty clay with peat layers Ag2 As2 Sh+ Greenish blue
13 silty clay Ag2 As2 Greenish blue
13.5 silty clay Ag2 As2 Greenish blue
14 silty clay Ag2 As2 Greenish blue
14 - 14.5 silty clay + organic detritus Ag2 As2 Sh+ Greenish blue
15 silty clay + peat layers Ag2 As2 Sh+ Greenish blue
15.5 silty clay + organic detritus Ag2 As2 Sh+ Greenish blue
16 silty clay Ag2 As2 Greenish blue
16 - 16.45 silty clay Ag2 As2 Greenish blue
17 silty clay + organic detritus Ag2 As2 Sh+ Blue
17.5 silty clay + organic detritus Ag2 As2 Sh+ Blue
18 silty clay Ag2 As2 Blue
18 - 18.5 silty sandy clay As2 Ag1 Ga1 Greenish blue
19 silty sandy clay As2 Ag1 Ga1 Greenish blue
19.5 silty clay Ag2 As2 Greenish blue
20 silty clay Ag2 As2 Greenish blue
20 - 20.5 sandy silt Ag2 Ga2 Greenish blue
21 silty sand Ga2 Ag2 Greenish blue
22 silty sand Ga2 Ag2 Greenish blue
22 - 22.45 silty sand Ga2 Ag2 Greenish blue
23 silty sand Ga2 Ag2 Greenish blue
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Depth (m) Description Troels-Smith Colour
23.5 silty sand Ga2 Ag2 Greenish blue
24 silty sand Ga2 As2 Greenish blue
24 - 24.45 clayey silt Ag2 As2 Greenish blue
25 - 25.50 clayey silt Ag2 As2 Greenish blue
26 clayey silt + organic material Ag2 As2 Sh+ Greenish blue
silty clay + lots of wood fragments and 27 detritus Ag2 As2 Sh+ Greenish brown
27.5 wood peat mixed in with silty clay Tl2 As1 Ag1 Brown
28 clayey silt Ag2 As2 Greenish blue
29 gravels Gg4
30 gravels Gg4
31 chalk White
32 chalk White
32.5 chalk White
A1a.17 Six trial pits, TP 401, 402, 403, 404, 405, 406, were opened using a JCB 3CX (Figure 4). Two of the pits were entirely in landfill debris to their maximum depth (TP 401 and 403). The four remaining trial pits entered into alluvium (TP 402, 404, 405 and 406). No significant organic remains or archaeological material was recorded from the trial pits.
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Figure 4: Lithostratigraphy of the Trial Pits at Brookside Farm
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Discussion
A1a.18 The results of the borehole and trial pit investigations at Rottingdean and Saltdean indicate that there is no reason to undertake further archaeological or palaeoenvironmental assessments at these sites. The results of the archaeological investigations at Sheepcote suggest that further, more extensive, investigations are required. The investigations in the lower Ouse valley at North Quay and Brookside Farm have produced extremely interesting records that provide significant potential for further palaeoenvironmental (including environmental archaeological) work.
A1a.19 The alluvial sediments of the lower Ouse valley (river mouth) were recorded by Jones (1971, 1981) and indicated c. 22m of estuarine sands, silts and clays, overlying a thin (c. 2.0m) bed of terrestrial and/or freshwater deposits. These passed down into fluvial sands and gravels (up to 6.0m) of probable Late Devensian Late Glacial age (c. 14,000-10,000 years before present (BP)). The substantial body of estuarine sediment was interpreted as the product of the marine transgression that accompanied the rise of sea level in the Early to Middle Holocene (c. 10,000-3000 BP) and which flooded the land surface in the lower valley of the Ouse. Further upstream Jones (1971) recorded a sequence of alluvium that yielded three radiocarbon dates (below) and confirmed the presence of a lengthy Holocene record in the alluvial deposits. TQ 413 092 -2.3m OD 3190 ±125 BP TQ 413 092 -5.5m OD 5670 ±170 BP TQ 413 013 -8.2m OD 6290 ±180 BP
A1a.20 The recorded sequences at North Quay and Brookside Farm, both within 2-3km of the mouth of the Ouse, appear to include elements that are difficult to reconcile with a relatively uncomplicated Early to Mid Holocene marine transgression model proposed by Jones. In particular, the evidence of peat development in the middle part of the Brookside Farm sequence (11.5m and 15m) and the presence of wood fragments at North Quay at approximately the same level (15m), suggests the local development of terrestrial conditions in the estuarine reach of the Ouse valley, probably in Middle Holocene times. A sample of wood from these layers at North Quay has been identified as Quercus sp (oak).
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A1a.21 The recovery of core samples from the estuarine alluvium of the Ouse at Brookside Farm and North Quay therefore provides an exciting opportunity to add to our understanding of Holocene sea level behaviour in the English Channel. Indeed the past behaviour of sea level and the interaction of marine and terrestrial processes at the coast and in river estuaries is a topic of current practical concern and active research on both sides of the English Channel (Shennan and Andrews, 2000; Pye and Allen, 2000). This topic has an important bearing on the archaeological record of occupation and land-use in coastal areas of southern England. Palaeoenvironmental reconstruction, improved dating and, in particular, further investigation of wood peat layers underlying estuarine sediments (at a depth of more than 25m below the ground surface at Brookside Farm) will undoubtedly add to the relatively small body of data on Early Holocene (c. 10,000-6000 BP) sea level behaviour in this geographical area. This is especially important due to the paucity of palaeoecological and archaeological records indicating human activity in the Ouse valley prior to the Romano-British period (East Sussex County Council Sites and Monuments Record). In addition, the quality of the existing stratigraphic record (Jones, 1971) would be greatly enhanced by employing a multidisciplinary approach, involving a range of independent environmental records. If further work is undertaken at Brookside Farm and North Quay, it is recommended that continuous borehole samples (e.g. U100) are obtained from the entire sedimentary sequence for laboratory assessment and possible analysis.
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References
Jones, D.K.C., 1971. The Vale of the Brooks. In: R.B.G. Williams (ed.), Guide to Sussex Excursions: 43-46. London: Institute of British Geographers.
Jones, D.K.C., 1981. The Geomorphology of the British Isles - Southeast and Southern England. London: Methuen.
Mott Macdonald, 2003a. Brighton and Hove UWWTD Scheme, Locations B1 – Black Rock and B3 – Kemp Town Gasworks, Geotechnical Desk Study Report. Croydon: Mott Macdonald.
Mott Macdonald, 2003b. Brighton and Hove UWWTD Scheme, Site B5 – Sheepcote Valley, Geotechnical Desk Study Report. Croydon: Mott Macdonald.
Mott Macdonald, 2003c. Brighton and Hove UWWTD Scheme, Location P6 – Peacehaven East, Geotechnical Desk Study Report. Croydon: Mott Macdonald.
Mott Macdonald, 2003d. Brighton and Hove UWWTD Scheme, Location P12 – Brookside Farm, Geotechnical Desk Study Report. Croydon: Mott Macdonald.
Mott Macdonald, 2003e. Brighton and Hove UWWTD Scheme, Location P18 – North Quay, Geotechnical Desk Study Report. Croydon: Mott Macdonald.
Mott Macdonald, 2003f. Brighton and Hove UWWTD Scheme, Location B22 – Shoreham Harbour, Geotechnical Desk Study Report. Croydon: Mott Macdonald.
Pye, K. and Allen, J.R.L., eds. 2000. Coastal and Estuarine Environments - Sedimentology, Geomorphology and Geoarchaeology. Geological Society of London, Special Publication 175.
Shennan, I. and Andrews, J. eds. 2000. Holocene Land-Ocean Interaction and Environmental Change around the North Sea. Geological Society of London, Special Publication 166.
Troels-Smith, J., 1955. Karakterisering af løse jordater (Characterisation of unconsolidated sediments). Danmarks Geologiske Undersøgelse 4:38-73.
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APPENDIX 2: TRIAL TRENCHING METHODOLOGY FOR MARINE
DRIVE (ROEDEAN PUMPING STATION) (RPS IN
ASSOCIATION WITH ARCHAEOLOGY SOUTH-EAST)
Aims and Objectives
A2.1 The general aim of the remaining evaluation at Marine Drive is to establish the character, date and function of any archaeological features within areas of development and to establish the need for a programme (or otherwise) of archaeological mitigation.
A2.2 Specific research aims for the evaluation are as follows;
To establish whether modern activities have removed any archaeology that mighty have been present at the location.
To establish prehistoric burial and settlement activity within the area extends into the site.
Proposals for Evaluation
A2.3 It is proposed that two trenches are excavated running e/w through the central area of the 3600m² worksite. Trench 1 would be 60m long by 1.6m wide, whilst trench 2 would be 30m long by 1.6m wide (see Figure 7). Both trenches are to be positioned within the traffic island once the island has been secured by the construction contractors (and safe working has been established). The trenches would be cut by a JCB or 360 degree excavator equipped with a toothless ditching bucket.
Generic Methodology
A2.4 All work will be undertaken to standards described in English Heritage’s Guidance Papers (1998a and 1998b) and by the Institute for Field Archaeologists (1994). In accepting a contract to undertake the works, ASE will take responsibility for the standards and levels of recording and reporting plus the preparation of Health and Safety documentation.
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A2.5 The archaeologists will follow the Code of Conduct of the Institute of Field Archaeologists.
A2.6 Service plans will be consulted by ASE prior to the field evaluation and trench locations may be modified accordingly. Any modifications to proposals will be agreed with RPS, the client and the County Archaeologist prior to the implementation of any change.
A2.7 All relevant health and safety legislation will be adhered to. A Health & Safety Risk Assessment will be prepared for archaeological works. Risk Assessments will be prepared by the archaeological contractor and submitted to the client /RPS Planning.
A2.8 The trenches will be machine stripped to the level of the highest archaeologically significant layer or in the absence of such layers, to the level of the undisturbed natural.
A2.9 The evaluation trenches will be opened by a mechanical excavator using a toothless ditching bucket under archaeological supervision. Topsoil and subsoil will be kept separate. Backfilling of trenches will be by machine re-deposition of spoil, with subsoil first and then topsoil, with tracking over the backfilled material.
A2.10 Where mechanical excavation is undertaken it shall avoid damage to archaeological remains and be limited to removal of “overburden” unless set out otherwise in this design. The mechanical excavator/s will operate under archaeological supervision at all time. “Overburden” will be removed under direction of the nominated person in charge of fieldwork or delegated archaeologists. Mechanical excavators shall not track over an area once excavated to the upper archaeological horizon.
A2.11 Following clearance of the trench all faces of the trench that require examination or recording will be cleaned using appropriate hand tools.
A2.12 The site grid and all trenches will be accurately surveyed using an EDM and will be related to the National Grid. The archaeological site grid will be marked on the trenching plans and will be marked on the ground. The trench locations will be accurately placed onto a copy of the Ordnance Survey map not smaller than 1:2500 following the excavation and the corners of the trenches will be allocated grid references.
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A2.13 A series of Temporary Bench Marks shall be surveyed as necessary in relation to an Ordnance Survey Bench Mark. The location of the bench marks and the TBM’s will be recorded on the trench plans. Plans and sections of all trenches, features and deposits will be related to their height above sea level.
A2.14 The County Archaeologist will be informed at the earliest opportunity of any archaeological features or deposits worthy of preservation and will be given opportunity to inspect such features.
A2.15 Significant archaeological features and deposits will be sampled by hand. This will normally entail 20% of linear features and 50% of discrete features.
A2.16 If deposits suitable for environmental sampling are encountered (such as dated excavated contexts of buried soils, well-sealed slowly silting features, sealed hearths, sealed features containing evident carbonised remains, peats, water-logged or cess deposits), bulk soil samples (40 litres or 100% of smaller features) will be taken for environmental analysis.
A2.17 A record of the full extent in plan of all archaeological deposits as revealed in the investigation will be made and will be related to the site grid at a scale of 1:10 or 1:20. ‘Single context planning’ will be used on deeply stratified sites. The information will be digitised on or off site for CAD application.
A2.18 The OD height of all principal strata and features will be calculated and indicated on the appropriate plans and sections. Each TBM will be levelled as part of a closed loop starting and finishing on either approved OSBMs or the schemes established secondary control. Where more than one TBM is required per site, the TBMs will be established as part of the same closed loop.
A2.19 All trenches, features and deposits will be photographed with both black and white and colour slide film. General shots of the site will also be taken. A scale and north arrow will be included in the photographs. Digital images will also be provided for use.
A2.20 A full photographic register will be maintained, including direction of shot, location and context number. A full photographic record of the investigations will be prepared. This will include black and white prints and colour transparencies (on
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35mm film), illustrating in both detail and general context the principal features and finds discovered. The photographic record will also include ‘working shots’ to illustrate more generally the nature of the archaeological investigation. The transparencies will be mounted in suitable frames for long-term curation in preparation for deposition with the archive.
A2.21 All archaeological features and deposits will be recorded by ASE using standard UCLFAU context sheets.
A2.22 Upon completion of each evaluation trench at least one long section (or representative part) will be drawn including a profile of the top of the natural deposits (extrapolated from cut features etc., if the trench has not been fully excavated). Other sections, including the half-sections of individual layers or features will be drawn as appropriate to 1:10 or 1:20.
A2.23 A ‘site location plan’ indicating the site north and based on the current Ordnance Survey 1:1250 map (reproduced with the permission of the Controller of HMSO) will be prepared. This will be supplemented by a trench plan at 1:200 (or 1:100), which will show the location of the areas investigated in relation to the investigation area and National Grid Reference. All sections should be located on plan with OS co- ordinates. The location of the OS bench marks used and the site TBM will also be indicated.
A2.24 All finds will be bagged and labelled with their relevant context number for washing and processing.
A2.25 The spoil heaps from the evaluation trenches will be checked for metal artefacts using a metal detector. A list of finds recovered by this technique will be included in the report.
A2.26 A ‘Harris Matrix’ stratification diagram will be used to record stratigraphic relationships. This record will be compiled and fully checked during the course of the evaluation. Spot dating should be incorporated where applicable during the course of the works.
A2.27 All relevant finds will be retained for assessment.
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Environmental Sampling
A2.28 Environmental sampling strategies will be developed subject to the requirements of the evaluation work and future mitigation strategies and the issues of potential contamination. If contamination is not an issue, specialist staff will have a role in ensuring that appropriate deposits are sampled to retrieve palaeoenvironmental and economic indicators to fulfil the project aims. Preparation, taking, processing and assessment of environmental samples will be in accordance with current best practice.
A2.29 The sampling strategy and methodology will be based on the following (subject to H&S considerations):
All collected samples will be labelled with context and sequential sample numbers;
Appropriate contexts will be bulk sampled for the recovery of carbonised plant remains and insects. Assemblages of charred crop remains are of particular importance and will be used to provide data in addition to the associated weed flora on agricultural activities, the economy of the site and its relationship to the river valley;
If occupation surfaces are encountered, spatially controlled collection of environmental bulk samples may be taken to aid evaluation procedures. Spatial co-ordinates will be recorded for all samples, and the sampling grid related to the site grid and Ordnance Survey grid. Assessment of spatial information should be undertaken to enable the degree of resolution to be defined following appropriate consultation;
Environmental samples will be taken where organic remains survive in well- stratified, datable deposits. Bulk samples (40 litre or the whole context dependent upon size) will be taken for wet sieving and flotation where there is clear indication of good analytical potential and dating evidence for such material (subject to evaluation requirements). Where there is potential for spatial variation in the distribution of such remains, the sampling strategy will
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include a percentage sample of each feature/deposit type, distributed throughout the excavation area, sufficient to ensure that such variation is detected;
Bulk samples may be taken, if appropriate, from significant datable waterlogged deposits for insects and macroscopic plant remains;
Sub-samples or monolith samples of waterlogged deposits and sealed buried soils with potential for pollen preservation will be taken for assessment if appropriate and columns of such samples will be taken through deposits where there is clear potential for recovering a datable sequence of environmental information;
Recovery of small animal bones, bird bone and large molluscs will normally be achieved through processing other bulk samples or 30 litre samples may be taken specifically to sample particularly rich deposits;
Undisturbed kubiena tin or column samples of sediments will be taken for micromorphology of buried soils where these are likely to shed light on the environmental development of the area;
Where suitable deposit sequences are encountered (normally waterlogged deposits with high palaeoenvironmental potential, in association with archaeological material), purposive radiocarbon sampling will be carried out at an appropriate interval.
If samples are taken, a pilot study will be undertaken as an initial stage of environmental processing. This will enable an assessment of which groups of samples are likely to be most productive for complete processing and further study.
Bulk samples will be processed using tank flotation unless considered detrimental to the samples or recovery rate (such as for waterlogged samples). Bulk samples will target recovery of plant remains (charcoal and macrobotanicals), fish, bird, small mammal and amphibian bone, and small artefacts. Waterlogged samples will be wet sieved through nested sieves and stored in wet, cool conditions or dried if considered an appropriate form of
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conservation for the remains. Specialist samples may also be taken from dry or waterlogged contexts. Such samples will target recovery of pollen (using monolith tins), molluscs, foraminifera, parasites and insects. Larger samples (80-100 litres) will be extracted wholesale from deposts rich in marine molluscs and large mammal bones. As a general rule waterlogged wood specimens will be recorded in detail in their original location. If removed they will be cleaned, photographed and a thin section sample will be taken for identification. Specimens will either be stored in wet cool conditions or dried if considered appropriate for the material. In all instances deposits with clear intrusive material shall be avoided.
Furnaces or kilns are not anticipated on this site but should these be encountered they will be left in situ such that they can be excavated at mitigation stage if required. In practice at evaluation stage it will be sufficient to identify the basic form, date and significance of such features. Industrial residues will be recorded and sampled in accordance with the Society of Museum Archaeologists (SMA, 1993) guidelines. The presence of such residues will always be recorded and quantified fully, even where comprehensive retention is considered to be inappropriate. Large technological residues will be collected by hand. Separate samples (c.10ml) will be collected where appropriate for identification of hammer scale and spherical droplets. The advice provided in the English Heritage/ Metallurgy Society document Archaeometallurgy in archaeological projects, will be referred to. Structural remains will be similarly recorded in accord with the SMA guidelines.
Treatment of Finds
A2.30 All pottery, bone, worked flint and other finds will be treated in a proper manner and to standards agreed in advance with the recipient museum. They will be exposed, lifted, cleaned, conserved, marked (according to site code, type and context), bagged and boxed in accordance with the guidelines set out in the United Kingdom Institute for Conservation’s ‘Conservation Guidelines No.2’. Most ceramic and other building material and burnt flint will be identified, counted, weighed and discarded.
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A2.31 The lithic and ceramic finds will be identified by specialists within Archaeology South- East, and preliminary identification of faunal remains may be undertaken if the nature of the deposits justifies such study. All finds in an unstable condition will be stabilised using passive conservation techniques where appropriate before being deposited with the receiving museum.
Human Remains
A2.32 Any human remains identified, including cremations, will be left in-situ, covered and protected, unless otherwise directed. Human remains will only be excavated after obtaining the relevant Ministry of Justice Licence, as required by the Burials Act of 1857 (amended 1981).
Treasure Trove
A2.33 All finds of gold and silver will be recorded, removed to a safe place and reported to the Coroner in accordance with the Treasure Act 1996. Where retrieval cannot be effected the same day, appropriate security measures will be put in place to safeguard the finds.
Finds and Environmental Specialists
A2.34 Appropriate specialist staff will be used on this project depending on the type of artefacts and soil samples recovered during the course of the fieldwork.
Health & Safety
A2.35 Risk Assessments will be prepared for archaeological works. The risk assessment will confirm appropriate levels of PPE to be worn by workers on site and all other pertinent risk avoidance procedures. Health and Safety must take priority over archaeological requirements. It is essential that all projects be carried out in accordance with safe working practices and under a defined Health and Safety Policy.
Welfare Facilities
A2.36 Welfare facilities will be provided by the archaeological sub-contractor.
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Insurance
A2.37 Archaeology South-East is insured against claims for: public liability to the value of £10,000,000 any one occurrence and in the aggregate for products liability; professional indemnity to the value of £10,000,000 any one occurrence; employer’s liability to the value of £25,000,000 each and every loss.
Liaison/Monitoring
A2.38 Archaeological work will be managed and monitored by RPS on behalf of Southern Water.
A2.39 The County Archaeologist or his assistant will be responsible for monitoring progress and standards throughout the project on behalf of the Local Planning Authority.
A2.40 Monitoring meetings will be arranged by RPS.
Post Fieldwork Methodology
A2.41 If the results merit, a post-excavation assessment report will be prepared, and a programme of post-excavation analysis and reporting along the lines recommended in Management of Archaeological Projects (English Heritage 1991) will agreed with the client and the relevant authorities.
A2.42 If it is agreed that the results do not merit the full procedure described in 9.1 above, a report will be prepared describing the site and the work undertaken, and giving sufficient archaeological and historical information to adequately understand the archaeological results.
A2.43 The report is to include as a minimum:
a) An Abstract summarising the scope and results of the archaeological watching brief.
b) An Introduction including:
the location of the site including National Grid Reference;
an account of the background and circumstances of the work;
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a description of the development proposals, planning history and planning reference together with the planning condition (where appropriate);
the scope and date of the fieldwork, the personnel involved and who commissioned it;
the nature of potential impacts arising from the proposals;
c) An account of the Archaeological Background of the development site including:
geology, soils and topography;
any known existing disturbances on the site;
background archaeological potential of the site. This should include a summary of the known Sites and Monuments Record entries generally within a 500m radius of the boundaries of the site. The SMR entries should be quoted with their full ESCC SMR identifier;
summary of any previous phases of archaeological investigation at the development site;
any constraints on the archaeological monitoring.
d) The Methodology employed during the watching brief will be detailed in the report.
e) The aims and objectives will be included.
f) The report will include a quantification of the archive contents, their state and future location.
g) A description of the Results of the archaeological monitoring. This description will include for each area observed:
the dimensions of the area observed;
the nature and depth of overburden soils encountered;
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description of all archaeological features and finds encountered in each area observed, their dimensions, states of preservation and interpretation;
a description of the geological subsoil encountered across the site;
heights related to Ordnance Datum (where practicable) should be provided for each feature and deposit.
for complex remains a Harris Matrix diagram should be provided.
h) The Finds recovered during the course of the watching brief will be described, quantified and assessed by artefact type within the report. The report will also provide an indication of the potential of each category of artefact for further analysis and research. For each category of artefact the report will describe the method of processing, any sub-sampling, conservation and assessment undertaken. Where appropriate, local reference collections will be referred to for descriptive and analytical consistency. Any implications for future archive, conservation or discard of the artefacts will also be detailed.
i) The report will include a table showing the contexts, classes and quantity of artefacts recovered, together with their date and interpretation.
j) The report will include an assessment of the Environmental potential of the site. Details will be provided of any environmental sampling undertaken in connection with the fieldwork and the results of any processing and assessment of the samples. The report will describe the method of processing, any sub-sampling and assessment. Any potential for future analysis of the samples or environmental remains recovered from the fieldwork will be described. Implications for future archive, conservation or discard of environmental samples or remains will be detailed.
k) The report will include, as appropriate, tables summarising environmental samples taken, together with the results of processing and assessment.
l) Any results from the evaluation involving the application of archaeological scientific techniques e.g. specialist dating will be included in the watching brief report.
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m) An Interpretation and Discussion of the archaeology of the site, including its location, extent, date, condition, significance and importance. This will include, even if no archaeology is identified as present on the site, description of areas of disturbance, non-archaeological deposits and changes in geological subsoil where appropriate.
n) A Conclusion with a summary of the archaeological results and how any archaeology observed relates to the development site. The effects of the development works on the archaeological remains will also be described. The report will highlight any areas of significant archaeological deposits that remain preserved within the development site. Particular note shall be made of any variations in the depth of overburden covering any archaeological deposits revealed.
o) The report will include comments on the effectiveness of the methodology employed and the confidence of the results and interpretation.
p) Figures / illustrations – The report shall include sufficient illustrations to support descriptions and interpretations within the report text. Figures will be fully cross-referenced within the document text. As a minimum the report shall include the following figures:
q) A site location plan tied into the Ordnance Survey at 1:1250 or in the case of larger sites at 1:2500. The plan will also include at least two National Grid points and show the site boundary;
r) A plan at 1:100 or 1:200 showing the layout of the development groundworks clearly indicating the areas observed. The plan will show significant archaeological features, coloured by phases or period as related to the development site. Where possible, projection of archaeological features outside of the areas observed shall be included on the plan. This plan will also include two National grid points;
s) Plans of the features revealed in each of the excavation areas at a larger scale e.g. 1:20 or 1:50; such plans will also illustrate areas of disturbance, change in subsoil and location of sections; The location of significant finds and samples taken will also be indicated;
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t) Relevant section drawings and soil trench profiles as appropriate;
u) Illustrations and/or photographs of significant finds shall be included where appropriate.
v) All report illustrations will be fully captioned and scale drawings will include a bar scale. Standard archaeological drawing conventions shall be used. Plan and section illustrations will include the numbers of all contexts illustrated. North will be included on all plans and shall be consistent. Sections will indicate the orientation of the section and the Ordnance Datum height of the section datum.
w) Black & White or Colour photographs shall be included where appropriate to illustrate the archaeology of the site, the development operations or the range of soil profiles encountered. All photographs shall be appropriately captioned.
A2.44 Upon completion of the fieldwork an OASIS (Online Access to the Index of Archaeological Investigations) form will be completed for the project. A print-out of the form will be included as an appendix to the final report.
A2.45 A draft report will be submitted to the County Archaeologist in the first instance for approval. Once any necessary changes have been made, the approved final report will be submitted to the client and should also be passed to the local planning authority with a further copy submitted to ESCC so that the results may be added to the Historic Environment Record. A short summary of the work will be prepared for the relevant local archaeological journal.
A2.46 A further digital copy of the report (including plans, illustrations and photographs) will be supplied to the East Sussex Historic Environment Record on CD-ROM in a .pdf format.
A2.47 The written and drawn archive will be deposited in an appropriate museum. Artefacts and ecofacts recovered during excavation form an important part of an archaeological site archive. Permission will be sought from the landowner to donate the finds from this project to an appropriate museum for deposition with the rest of the archive. The archive will be prepared according the principles of Management of
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Archaeological Projects (English Heritage, 1991) and the requirements of the recipient museum.
A2.48 Project Management for RPS will be undertaken by Rob Masefield and for ASE by Neil Griffin and/or Daryl Palmer (as Project Manager) and Louise Rayner (Post- Excavation Manager).
Publication
A2.49 Interim publication of the results, at least to summary level, will take place in the year following the fieldwork. The summary will be published in a round up of excavation in SAC.
A2.50 Once the site archive and evaluation reports have been completed the need for further mitigation strategies in response to development will be assessed. If no further mitigation strategies are required, a Phase 2 Review (English Heritage 1991, 13) will be undertaken. Phase 2 Review can result in either a formal assessment stage or publication, as set out in Map II, Appendix 7 (English Heritage 1991, 39-41).
A2.51 If further mitigation is required, publication in local or national journals appropriate to the results will be considered.
Copyright
A2.52 It is normal practice for both the copyright and ownership of the paper and any digital archive resulting from an archaeological project to rest with the originating body (usually the archaeological contractor). The originating body will deposit the archive in a museum or other appropriate repository on the completion of the project, and normally transfers title and/or licences for use of the archive at this stage.
A2.53 However, until notified to the contrary, existing and future copyright and all other proprietary rights in all drawings, details, plans, specifications, schedules, reports, calculations and other work originated or made in the course of performing the scope of works will be assigned to Southern Water.
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Programme
A2.54 Start date to be determined. The works should take approximately two weeks to complete.
A2.55 Subsequent programmes of works (if required) can only be assessed once Stage 1 field evaluation is complete.
Bibliography
Dept. of Environment, 1990, Planning Policy Guidance 16 (PPG16)
English Heritage, 1991, Management of Archaeological Projects
English Heritage, 1998a, Archaeological Guidance Paper 3: Standards and Practices in Archaeological Fieldwork. English Heritage London Region.
English Heritage, 1998b, Archaeological Guidance Paper 4: Standards and Practices in Archaeological Reports. English Heritage London Region
Institute of Field Archaeologists 1994 Standard and Guidance for Archaeological Field Evaluations
Institute of Field Archaeologists 1997 Code of Conduct.
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APPENDIX 3: WATCHING BRIEF METHODOLOGY (AFTER
ARCHAEOLOGY SOUTH EAST)
A3.1 The general aim of the archaeological work is to monitor any intrusive ground work in order to ensure that any features, artefacts or ecofacts of archaeological interest exposed and affected by the excavations are recorded and interpreted to appropriate standards and a report of the findings produced.
A3.2 The following intrusive groundworks will be monitored by an archaeologist.
Continuous monitoring of general ground reduction within work-site areas of (i.e. in areas that have not been investigated previously via ‘strip and map’).
Ground reduction within the dry valleys at work-site locations.
Methods
A3.3 New ground works excavations undertaken by engineering/building contractors will be monitored at all times by an archaeologist until/unless it becomes clear beyond reasonable doubt that no archaeological remains are present (e.g. once excavation reaches undisturbed natural subsoils, below which there will be no archaeological remains present - after the recording of any significant remains if present at higher levels). Any machine used for removal of material above undisturbed natural subsoil will be fitted with a toothless bucket of appropriate width whenever practicable.
A3.4 Where new excavations reveal archaeological features, machine or hand excavation by contractor’s staff will cease. The features will then be hand excavated and recorded to archaeological standards by the archaeologist(s) in attendance. Exposures will be hand cleaned by archaeologists as necessary to clarify the presence/absence and nature of any features. Adequate time will be made available for appropriate archaeological excavation by hand to identify and record the remains as far as possible within the limits of the works in order to extract archaeological and environmental information, should this prove necessary. A final decision on site as to how to proceed, in the event that significant remains are revealed by the Watching Brief, will be determined in agreement with the County Archaeologist.
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A3.5 This will enable any archaeological deposits and features, disturbed during the proposed works, to be adequately recorded in line with the advice given in PPG16 (the Government’s advice on Archaeology and Planning).
A3.6 The spoil from the excavations will also be inspected by archaeologists to recover any artefacts or ecofacts of archaeological interest.
A3.7 Casper Johnson, East Sussex County Archaeologist (ESCC) will be kept informed of progress so that he may monitor the archaeological work from the outset of ground works and inform the Local Planning Authority (LPA) of developments as necessary.
A3.8 All archaeological features will be recorded according to standard UCLFAU practice. Where practicable, all features will be planned at 1:20 and section drawings will be at 1:10, unless this is impractical in which case an alternative will be agreed with the County Archaeologist. Drawings will be on plastic draughting film. Features and deposits will be described on standard pro-forma recording sheets used by UCLFAU. All remains will be levelled with respect to the nearest Ordnance Survey benchmark. A photographic record will be made in monochrome, colour transparency and digitally (minimum resolution 3 megapixels).
A3.9 If deposits suitable for environmental sampling are encountered (such as dated excavated contexts of buried soils, well-sealed slowly silting features, sealed hearths, sealed features containing evident carbonised remains, peats, water-logged or cess deposits), bulk soil samples (40 litres or 100% of smaller features) will be taken for environmental analysis. In the case of the dry valley deposits further advice may be taken from Archaeoscape on the extraction of additional monoliths.
A3.10 Any finds believed to fall potentially within the statutory definition of Treasure, as defined by the Treasure Act 1996, shall be reported to the Finds Liaison Officer (based at Barbican House Museum, Lewes). Should the find’s status as treasure be confirmed the Coroner, the landowner and the County Archaeologist will also be informed. A record shall be provided to the Coroner and to the County Archaeologist of the date and circumstances of discovery, the identity of the finder, and the exact location of the find(s) (OS map reference to within 1 metre, and find spot(s) marked onto the site plan).
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A3.11 All work will be carried out in accordance with the Recommended Standard Conditions for Archaeological Fieldwork, Recording, and Post-Excavation Work (Development Control) in East Sussex (2003).
Treatment of Artefacts and Ecofacts
A3.12 If human remains are found, work will cease and all necessary statutory provisions followed. Casper Johnson, County Archaeologist, ESCC, RPS, the main contractor and the client will be informed immediately.
A3.13 Pottery, worked flint, metal and other finds of archaeological significance will be retained and treated according to standard Archaeology South-East procedures. Identification of retained finds will be undertaken by staff of, and specialists contracted by, Archaeology South East as necessary.
A3.14 Bulk samples will be processed using tank flotation unless considered detrimental to the samples or recovery rate (such as for waterlogged samples). Bulk samples will target recovery of plant remains (charcoal and macrobotanicals), fish, bird, small mammal and amphibian bone, and small artefacts. Waterlogged samples will be wet sieved through nested sieves and stored in wet, cool conditions or dried if considered an appropriate form of conservation for the remains. Specialist samples may also be taken from dry or waterlogged contexts. Such samples will target recovery of pollen (using monolith tins), molluscs, foraminifera, parasites and insects. Larger samples (80-100 litres) will be extracted wholesale from deposits rich in marine molluscs and large mammal bones. As a general rule waterlogged wood specimens will be recorded in detail in their original location. If removed they will be cleaned, photographed and a thin section sample will be taken for identification. Specimens will either be stored in wet cool conditions or dried if considered appropriate for the material. In all instances deposits with clear intrusive material shall be avoided.
Reporting and Archive
A3.15 If the results merit, a post-excavation assessment report will be prepared, and a programme of post-excavation analysis and reporting along the lines recommended in Management of Archaeological Projects (English Heritage 1991) will agreed with the client and the relevant authorities. In practice the results of watching brief
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elements will be combined with the strip and map and evaluation results in terms of reporting.
A3.16 The report is to include an Abstract summarising the scope and results of the archaeological watching brief, an Introduction including:
the location of the site including National Grid Reference;
an account of the background and circumstances of the work;
a description of the development proposals, planning history and planning reference together with the planning condition (where appropriate);
the scope and date of the fieldwork, the personnel involved and who commissioned it;
the nature of potential impacts arising from the proposals;
A3.17 An account of the Archaeological Background of the development site including:
geology, soils and topography;
any known existing disturbances on the site;
background archaeological potential of the site. This should include a summary of the known Sites and Monuments Record entries generally within a 500m radius of the boundaries of the site. The SMR entries should be quoted with their full ESCC SMR identifier;
summary of any previous phases of archaeological investigation at the development site;
any constraints on the archaeological monitoring.
A3.18 The Methodology employed during the watching brief will be detailed in the report. Any aims and objectives will be included as will any further objectives identified during the course of the watching brief. The frequency of monitoring visits, ground works observed and any constraints experienced while carrying out the monitoring will be detailed.
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A3.19 The report will include a quantification of the archive contents, their state and future location.
A3.20 A description of the Results of the archaeological monitoring. This description will include for each area observed:
the dimensions of the area observed;
the nature and depth of overburden soils encountered;
description of all archaeological features and finds encountered in each area observed, their dimensions, states of preservation and interpretation;
a description of the geological subsoil encountered across the site;
heights related to Ordnance Datum (where practicable) should be provided for each feature and deposit.
for complex remains a Harris Matrix diagram should be provided.
A3.21 The Finds recovered during the course of the watching brief will be described, quantified and assessed by artefact type within the report. The report will also provide an indication of the potential of each category of artefact for further analysis and research. For each category of artefact the report will describe the method of processing, any sub-sampling, conservation and assessment undertaken. Where appropriate, local reference collections will be referred to for descriptive and analytical consistency. Any implications for future archive, conservation or discard of the artefacts will also be detailed.
A3.22 The report will include a table showing the contexts, classes and quantity of artefacts recovered, together with their date and interpretation.
A4.23 The report will include an assessment of the Environmental potential of the site. Details will be provided of any environmental sampling undertaken in connection with the fieldwork and the results of any processing and assessment of the samples. The report will describe the method of processing, any sub-sampling and assessment. Any potential for future analysis of the samples or environmental remains recovered
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from the fieldwork will be described. Implications for future archive, conservation or discard of environmental samples or remains will be detailed.
A3.24 The report will include, as appropriate, tables summarising environmental samples taken, together with the results of processing and assessment.
A4.25 Any results from the watching brief involving the application of archaeological scientific techniques e.g. specialist dating will be included in the watching brief report.
A3.26 An Interpretation and Discussion of the archaeology of the site, including its location, extent, date, condition, significance and importance. This will include, even if no archaeology is identified as present on the site, description of areas of disturbance, non-archaeological deposits and changes in geological subsoil where appropriate.
A3.27 A Conclusion with a summary of the archaeological results and how any archaeology observed relates to the development site. The effects of the development works on the archaeological remains will also be described. The report will highlight any areas of significant archaeological deposits that remain preserved within the development site. Particular note shall be made of any variations in the depth of overburden covering any archaeological deposits revealed.
A3.28 The report will include comments on the effectiveness of the methodology employed and the confidence of the results and interpretation.
A3.29 Figures / illustrations – The report shall include sufficient illustrations to support descriptions and interpretations within the report text. Figures will be fully cross- referenced within the document text. As a minimum the report shall include the following figures:
a site location plan tied into the Ordnance Survey at 1:1250 or in the case of larger sites at 1:2500. The plan will also include at least two National Grid points and show the site boundary;
a plan at 1:100 or 1:200 showing the layout of the development groundworks clearly indicating the areas observed. The plan will show significant archaeological features, coloured by phases or period as related to the development site. Where possible, projection of archaeological features outside
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of the areas observed shall be included on the plan. This plan will also include two National grid points;
plans of the features revealed in each of the excavation areas at a larger scale e.g. 1:20 or 1:50; such plans will also illustrate areas of disturbance, change in subsoil and location of sections; The location of significant finds and samples taken will also be indicated;
relevant section drawings and soil trench profiles as appropriate;
illustrations and/or photographs of significant finds shall be included where appropriate.
A3.30 All report illustrations will be fully captioned and scale drawings will include a bar scale. Standard archaeological drawing conventions shall be used. Plan and section illustrations will include the numbers of all contexts illustrated. North will be included on all plans and shall be consistent. Sections will indicate the orientation of the section and the Ordnance Datum height of the section datum.
A3.31 Black & White or Colour photographs shall be included where appropriate to illustrate the archaeology of the site, the development operations or the range of soil profiles encountered. All photographs shall be appropriately captioned.
A3.32 A draft report comprising both the strip and map and watching brief elements will be submitted to the County Archaeologist in the first instance for approval. Once any necessary changes have been made, the approved final report will be submitted to the client and should also be passed to the local planning authority with a further copy submitted to ESCC so that the results may be added to the Historic Environment Record. A short summary of the work will be prepared for the relevant local archaeological journal.
A3.33 A further digital copy of the report (including plans, illustrations and photographs) will be supplied to the East Sussex Historic Environment Record on CD-ROM in a .pdf format.
A3.34 The written and drawn archive will be deposited in an appropriate museum. Artefacts and ecofacts recovered during excavation form an important part of an
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archaeological site archive. Permission will be sought from the landowner to donate the finds from this project to an appropriate museum for deposition with the rest of the archive. The archive will be prepared according the principles of Management of Archaeological Projects (English Heritage, 1991) and the requirements of the recipient museum.
A3.35 Upon completion of the fieldwork an OASIS (Online Access to the Index of Archaeological Investigations) form will be completed for the project. A print-out of the form will be included as an appendix to the final report.
Health and Safety
A3.36 A risk assessment will be prepared before the commencement of fieldwork. All relevant legislation will be followed.
Insurance
A3.37 Archaeology South East is insured against claims for: employer’s liability to the value of £25,000,000 each and every loss; primary public/products liability to the value of £10,000,000 any one occurrence and in the aggregate for products liability, with an extension for no-fault compensation up to £10,000,000 in the aggregate; professional indemnity to the value of £10,000,000 any one occurrence.
Project Management
A3.38 This project will be managed for ASE by Neil Griffin (fieldwork) and Louise Rayner (post-excavation).
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APPENDIX 4: SPECIFICATION FOR ARCHAEOLOGICAL
EXCAVATION (IF REQUIRED) (RPS IN ASSOCIATION
WITH ARCHAEOLOGY SOUTH EAST)
Introduction
A4.1 At the time of writing there are no specific areas of archaeological excavation required at any of the infrastructure sites. However, the project includes provision that should significant archaeology be revealed by the strip and map process there may a requirement for limited areas of detailed excavation. This methodology is therefore required in the event that such works are required during the course of the project.
Machine Stripping
A4.2 All stripping of areas subject to archaeological excavation will be stripped by a 360 excavator equipped with a toothless ditching bucket whilst under archaeological supervision and guidance. Overburden deposits (e.g. demolition material, modern made ground) will be removed in spits no greater than 0.1m in thickness. Machine excavation will be carried out on to the top of archaeological deposits or the surface of geological drift deposits, whichever is uppermost. Care will be taken not to machine off seemingly homogenous layers that may include the upper parts of archaeological features. The resultant surfaces will be cleaned as necessary and planned.
General Methodology
A4.3 Once the machine strip of the areas is complete a fixed site grid will be established relative to Ordnance Datum using a Total Station. A full pre-excavation plan will be prepared as the stripping progresses using Global Positioning System (GPS) planning technology in combination with Total Station surveying. This will be available to the Project Manager, the Supervisor and the ESCC County Archaeologist immediately, or at the latest the day after the recording has taken place. This pre-excavation plan will be available in Autocad or PDF format and will be
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printed at a suitable scale (1:20 or 1:50) for on site use. The plan will be updated by regular visits to site by the Archaeology South-East Surveyor who will plot excavated features and record levels in close consultation with the Supervisor and/or the excavators. Where it is deemed necessary (for example detailed structural features or burials) features will be hand planned at a scale of 1:20 from the grid and then digitised to be included on the overall plan.
A4.4 All excavation work will be carried out in line with Recommended Standard Conditions for Archaeological Fieldwork, Recording, and Post-Excavation Work (Development Control) in East Sussex (ESCC, September 2003). Specifically Annexes D and E apply for excavation fieldwork standards.
A4.5 After the cleaning and planning of the excavation areas a sample excavation strategy will be agreed with the ESCC County Archaeologist. As a minimum the following sampling strategy will be employed:
all structures and all zones of specialised activity (e.g. funerary, ceremonial, industrial, agricultural processing) will be fully excavated and all relationships recorded.
ditches and gullies will have all relationships defined, investigated and recorded. All terminals will be excavated. Sufficient of the feature lengths will be excavated to determine the character of the feature over its entire course; the possibility of recuts of parts, and not the whole, of the feature will be considered. This will be achieved by a minimum 25% sample of each feature. Sufficient artefact assemblages will be recovered (where possible) to assist in dating the stratigraphic sequence and for obtaining ample ceramic groups for comparison with other sites.
all pits will initially be half-sectioned and fully recorded. Pits may subsequently be fully excavated to facilitate 100% collection of artefact assemblages, subject to discussion with the ESCC County Archaeologist.
for post and stake holes where they are clearly not forming part of a structure (see above) 100% (by number) will be half-sectioned ensuring that all
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relationships are investigated. Where deemed necessary, by artefact content, a number may demand full excavation.
for other types of feature such as working hollows, quarry pits etc., all relationships at least will be ascertained and the level of sample excavation agreed with the ESCC County Archaeologist in order to establish as a minimum their extent, date and function.
for layers a decision agreed on-site with the ESCC County Archaeologist will be made as to the extent that they will be excavated. The factors governing the judgement will include the possibility that they mask earlier remains, the need to understand function and depositional processes, and the necessity to recover sufficient artefacts to date the deposit and to meet the project aims.
A4.6 Consideration will be given to employing the single context recording system if remains are sufficiently complicated. The stratigraphy here is unlikely to require this, although this will be kept under review.
A4.7 All excavation spoil will be removed from site, leaving the site features clear to full view at all times during the excavation. Due the size of the site blank areas will be identified and agreed with ESCC Archaeologist. These will then be used as “spoil heaps” within the stripped area to reduce the need to barrow spoil significant distances across the site.
A4.8 All excavated deposits and features will be recorded according to current professional standards using the standard context record sheets used by UCLFAU. Artefacts will be retained from all deposits.
A4.9 The sampling strategies for palaeoenvironmental remains will be established once the area has been stripped, and will be decided in conjunction with the English Heritage Science Advisor, the Archaeology South-East Environmental Officer and the ESCC County Archaeologist. As a general rule bulk samples of between 40 and 60 litres will be collected for the recovery of carbonised remains, animal bones, molluscs and other small artefacts. Bulk samples of 10-30 litres will be taken from waterlogged deposits for analysis of macroscopic plant remains. Columns for pollen analysis will be taken where appropriate. Larger samples of 80-100 litres will be taken to sample bone assemblages where necessary.
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A4.10 Any finds of human remains will be left in situ, covered and protected. The coroner's office will be informed. Excavation, recording and removal will only take place under the relevant licence and local authority environmental health regulations.
A4.11 All finds that are covered by the Treasure Act will be moved to a safe place and reported to the Coroner's office according to the procedures of this Act. Where removal cannot be effected on the same working day as the discovery, suitable security measures will be taken to protect the artefacts from theft or damage.
A4.12 The excavation area and spoil will be metal detected for artefacts.
A4.13 A full black and white, and colour (35mm transparency) photographic record will be maintained. This will illustrate the principal features and finds both in detail and in a general context. The photographic record will also include working shots to represent more generally the nature of the fieldwork and where appropriate overall photographs of the excavated site and/or principle features for publication. A digital photographic record will also be maintained.
A4.14 Once the excavation areas have been fully recorded to the satisfaction of ESCC they will be handed back to the developer.
Health and Safety
A4.15 Health and Safety must take priority over archaeological requirements. It is essential that all projects be carried out in accordance with safe working practices and under a defined Health and Safety Policy. A risk assessment for the project will be prepared prior to the commencement of work and all relevant health and safety regulations will be adhered to.
Report and Archive Preparation
A4.16 On completion of on-site works, the site archive will be compiled. This will contain all the data collected during the evaluation and excavations including records, finds and environmental samples. It will be quantified, ordered, indexed and internally consistent.
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A4.17 All retained finds after cleaning, conservation and packaging will be assessed and recorded using pro forma recording sheets. Initial artefact dating will be integrated with the site matrix.
A4.18 All retained environmental samples will be processed and assessed by experienced and qualified staff and recorded using pro forma recording sheets.
A4.19 All pottery recovered from the excavations will be washed and marked with the site code (SKP 06) to identify the site and context. Most ceramic and other building material and burnt flint will be identified, quantified and recorded prior to discard. Samples will be retained as appropriate. Finds will be bagged in polythene bags according to type and context. All finds work will be carried out in accordance with the IFA’s Guidelines for Finds Work.
A4.20 The site archive will be assembled in accordance with the guidelines set out in English Heritage’s Management of Archaeological Projects 2 and in accordance with the guidelines published in Guidelines for the Preparation of Excavation Archives for Long-term Storage (United Kingdom Institute for Conservation, 1990) and Standards in the Museum Care of Archaeological Collections (Museums and Galleries Commission, 1994).
A4.21 Permission will be sought from the landowner to deposit the finds and paper archive in an appropriate local museum, in this case preferably Brighton Museum.
A4.22 An Online Access to the Index of Archaeological Investigations (OASIS) form will be completed online at http://ads.ahds.ac.uk/project/oasis/ following the completion of all fieldwork and a printout included as an appendix to the final report.
Post-Excavation Assessment and Analysis
A4.23 A post-excavation assessment report for the evaluation and excavations will be prepared within six months of completion of the site work. A brief summary report will be submitted to the client and ESCC County Archaeologist within ten working days from the end of the fieldwork if required.
A4.24 The report will be in line with guidelines set out in Management of Archaeological Projects 2 (English Heritage, 1991) and will adhere to the standards laid out in
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Recommended Standard Conditions For Archaeological Fieldwork, Recording, and Post-Excavation Work (Development Control) in East Sussex (ESCC, September 2003). Specifically section 6 and Annex C apply for post excavation reporting standards.
A4.25 A draft copy of the report will be sent to the ESCC Archaeologist in the first instance for his comments and approval. Once the report has been accepted further copies and one electronic copy in PDF format will be sent to ESCC and the client as appropriate. A copy will be forward to Lewes District Council by the client or by Archaeology South-East on their behalf.
A4.26 A copy of the post excavation report will be supplied to the County SMR on the understanding that it will become a public document after an appropriate period of time not exceeding six months.
A4.27 Agreement shall be reached with the ESCC County Archaeologist regarding the format and destination of subsequent publication(s) arising from all investigations (evaluation, excavation etc) and the agreed post-excavation programme of the site. A paper suitable for publication will be produced within 24 months of completion of all work on the site.
General
A4.28 Archaeology South-East will work under the overall archaeological project management of RPS (Rob Masefieild) on this project. ASE conforms to the standards of professional conduct outlined in the Institute of Field Archaeologists' Code of Conduct, the IFA Code of Approved Practice for the Regulation of Contractual Arrangements in Field Archaeology, the IFA Standards and Guidance for Desk Based Assessments, Field Evaluations etc., and the British Archaeologists and Developers Liaison Group Code of Practice.
A4.29 Archaeology South-East will liaise with local archaeological bodies (both professional and amateur) in order that information about particular sites is disseminated both ways (subject to client confidentiality).
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Insurance
A4.30 Archaeology South-East is insured against claims for: employer’s liability to the value of £25,000,000; public liability to the value of £10,000,000 any one occurrence and in the aggregate for products liability, with an extension for no fault compensation up to £10,000,000 in the aggregate; professional indemnity to the value of £10,000,000 any one occurrence.
Bibliography
ESCC, September 2003. Recommended Standard Conditions for Archaeological Fieldwork, Recording, and Post-Excavation Work (Development Control) in East Sussex
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APPENDIX 5: BRIGHTON AND HOVE WWTW ROUTE
INFRASTRUCTURE: PROPOSAL FOR
ENVIRONMENTAL ARCHAEOLOGICAL
LABORATORY ANALYSIS AND REPORTING FOR
AN ENVIRONMENTAL ARCHAEOLOGICAL
‘WATCHING BRIEF’ AS REQUIRED
(ARCHAEOSCAPE)
General Advice/Attendance as Required
A5.1 The project also makes provision for Archaeoscape attendance during dry valley soil reduction to advise on any further sampling that could usefully contribute additional data to existing database.
Background to Archaeoscape
Experience
A5.2 Established at the Department of Geography, Royal Holloway University of London in 1996, ArchaeoScape is an expert environmental archaeological (palaeoenvironmental and palaeoeconomic) interpretation facility capable of providing a quality service for archaeological units, government organisations and environmental consultancies. Since 1996, the business has expanded to include a network of other specialists with expertise in archaeology, archaeological science and historic landscape studies, and has close links with the Departments of Geology, Biology, History and Classics at Royal Holloway. The business commands a client- base of twenty-five organisations, including English Heritage, English Nature, Canterbury Archaeological Trust Ltd, Cotswold Archaeology, RPS Planning Transport and Environment, CgMs Consulting, Pre-Construct Archaeology Ltd, Archaeological Development Services Ltd and AOC Archaeology. Projects
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conducted by members of ArchaeoScape involve investigations in the UK and abroad.
Expertise
A5.3 Core staff (full CV of all staff available upon request):
Nicholas Branch BSc (Archaeology) MSc (Bioarchaeology) PhD (Geography) Lecturer in Environmental Archaeology and ArchaeoScape Director Archaeobotanist Palynology).
Christopher Green BA (Geography) DPhil (Geography) Senior Geoarchaeologist.
Robert Batchelor BSc (Geology and Geography) Archaeobotanist (Palynology).
Peter French PhD (Geography) Geoarchaeologist.
Gemma Swindle BSc (Geography) MSc (Quaternary Science) ArchaeoScape Projects Manager.
Kevin Williams - Environmental Archaeologist (Technician).
James Reid - Environmental Archaeologist (Technician).
A5.4 Selected Publications by ArchaeoScape Staff:
Green, C.P. 1998 Building Stones in prehistoric Wessex, The Hatcher Review, 5, 18- 26.
Green, C.P. 1999 Pre-Anglian gravel deposits of the River Thames and its tributaries between Goring and Cromer, Proceedings of the Geologists' Association, 110, 117- 132.
Masefield, R., Branch, N.P., Couldrey, P., Goodburn, D. and Tyers, I. 2003 A later Bronze Age well complex at Swalecliffe, Kent, The Antiquiries Journal, 83, 47-121.
Turney, C.S.M., Kershaw, A.P., Clemens, S.C., Branch, N., Moss, P.T. and Fifield, L.K. 2004 Millennial and orbital variations of El Nino/Southern Oscillation and high- latitude climate in the last glacial period, Nature, 428, 306-310.
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Branch, N.P. and Green, C.P. 2004 The environmental history of Surrey, In: Cotton, J., Crocker, G. and Graham, A. (eds.), Aspects of Archaeology and History in Surrey: towards a research framework for the county, Guildford: Surrey Archaeological Society.
Branch, N.P. 2004, Late Wurm lateglacial and Holocene environmental history of the Ligurian Apennines, Italy, In: Balzaretti, R., Pearce, M. and Watkins, C. (eds.), Ligurian Landscapes, Studies in Archaeology, Geography and History, 7-69. Accordia: London.
Keeley, H., Allison, E., Branch, N.P., Cameron, N., Dobinson, S., Ellis, I., Ellison, P., Fairbairn, A., Green, C., Hunter, R., Lee, J., Locker, A., Lowe, J., Palmer, A., Robinson, E., Stewart, J. and Wilkinson, K. 2004 The environmental evidence, In: Clark, P. (ed.), The Dover Bronze Age Boat, 229-250. English Heritage: London
Branch, N.P., Canti, M.G., Clark, P. and Turney, C.S.M. 2005 Environmental Archaeology: Theoretical and Practical Approaches, Edward Arnold: London
Green, C.P., Branch, N.P., Coope, G.R., Field, M.H., Keen, D.H., Wells, J.M., Schwenninger, J.L. Preece, R.C., Schreve, D.C., Canti, M.G. and Gleed-Owen, C.P. 2005 Marine Isotope Stage 9 environments of fluvial deposits at Hackney, north London, UK. Quaternary Science Reviews, 25, 89-113.
Turney, C.S.M., Kershaw, A.P., James, S., Branch, N.P., Cowley, J., Fifield, L.K., Jacobsen, Australia, over the past 50 ka. Palaeogeography, Palaeoclimatology, Palaeoecology, 233, 187-203.
Turney, C.S.M., Kershaw, J.J. Lowe, van der Kaars, S., Johnston, R., Rule, S., Moss, P., Radke, L., Tibby, J., McGlone, M.S., Wilmshurst, J.M., Vandergoes, M.J., Fitzsimons, S.J.,, Bryant, C., James, S., Branch, N.P., Cowley, J., Kalin, R.M., Ogle, N., Jacobsen, G. and Fifield, L.K. 2006 Climate variability in the southwest Pacific during the Last Termination (20-10 kyr BP). Quaternary Science Reviews, 25, 886- 903.
Branch, N.P., Green, C.P., Swindle, G.E., Vaughan-Williams, A., Williams, A. and Wyatt, C. 2006 A Neolithic Monumental Landscape: The Environmental Context. In: Carew, T., Bishop, B., Meddens, F. and Ridgeway, V., Unlocking The Landscape,
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Archaeological Excavations at Ashford Prison, Middlesex. Pre-Construct Archaeology Ltd Monograph, 5, 25-26.
Branch, N.P., Green, C.P., Swindle, G.E., Vaughan-Williams, A., Williams, A. and Wyatt, C. 2006 A Bronze Age Field System: The Environmental Context. In: Carew, T., Bishop, B., Meddens, F. and Ridgeway, V., Unlocking The Landscape, Archaeological Excavations at Ashford Prison, Middlesex. Pre-Construct Archaeology Ltd Monograph, 5, 36.
Branch, N.P., Green, C.P., Swindle, G.E., Vaughan-Williams, A., Williams, A. and Wyatt, C. 2006 The Iron Age Settlement: The Environmental Context. In: Carew, T., Bishop, B., Meddens, F. and Ridgeway, V., Unlocking The Landscape, Archaeological Excavations at Ashford Prison, Middlesex. Pre-Construct Archaeology Ltd Monograph, 5, 74-75.
Branch, N.P., Kemp, R.A., Silva, B., Meddens, F.M., Williams, A., Kendall, A. and Pomacanchari, C.V. 2006 Test the sustainability and sensitivity to climatic change of terrace agricultural systems in the Peruvian Andes: a pilot study. Journal of Archaeological Science xx, 1-9.
Kemp, R., Branch, N.P., Silva, B., Meddens, F., Williams, A., Kendall, A. and Pomacanchari, C.V. 2006 Pedosedimentary, cultural and environmental significance of palaeosols within Pre-Hispanic agricultural terraces in the southern Peruvian Andes. Quaternary International xx, xx.
Leary, J., Branch, N.P. and Bishop, B. 2006 10,000 years in the life of the river Wandle: excavations at the former Vinamul site, Butter Hill, Wallington. Surrey Archaeological Collections 92, 1-28.
Resources
A5.5 Royal Holloway Geography Department (University of London) is a grade 5* research facility. Facilities, both internal and external to the Department, include:
• Field equipment for conducting survey and mapping (e.g. geophysical, electronic totalling stations and geographical positioning systems), and intrusive investigations (e.g. conventional and drilling equipment)
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• Computing and computer graphics suite supporting PC systems, ArcView geographical information systems, and remote sensing
• Palaeoecological laboratories (e.g. pollen and plant macrofossil analysis)
• Sedimentology and soil science laboratories (e.g. soil micromorphology)
• Geochemistry laboratories (e.g. atomic absorption spectrometry and ICP- AES)
• Geochronology laboratories (e.g. optical and thermo-luminescence dating)
• Artefact analysis laboratories (e.g. gas-liquid chromatography for organic residue analysis)
Project Management
A5.6 Dr. Nick Branch will manage the project, with assistance from the Royal Holloway Research and Enterprise Office (Financial Coordinators). Dr. Branch will direct members of ArchaeoScape, liaise with RPS Planning Transport and Environment and are responsible to the Head of the Geography Department (Prof. F. Driver).
Health, Safety and Risk Assessment
A5.7 Details of Departmental field and laboratory regulations (e.g. COSHH) may be obtained from Mr Robin Hunter, Departmental Superintendent, Geography Department, Royal Holloway.
Insurance
• Employers Liability
Commercial Union, Apex Plaza, Forbury Road, Reading, Berkshire
Policy No. EL946P18109
Limit of Indemnity £25,000,000 each and every loss
• Primary Public / Products Liability
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Gerling, 50 Fenchurch Street, London, EC3M 3JY
Policy No. 62/901862/D
Limit of Indemnity £10,000,000 any one occurrence and in the aggregate for Products Liability
• Professional Indemnity
Royal and Sun Alliance, 100 Kings Road, Reading, Berkshire
Policy No. GA10160340/7
Limit of Indemnity £10,000,000 any one occurrence
Summary of Previous Work
A5.8 A summary of the original aims and objectives and the results of previous work undertaken by ArchaeoScape as part of the ongoing environmental archaeological investigations is outlined below.
Original Aims and Objectives
A5.9 Along the route of the Brighton to Peacehaven pipeline: 2006. An evaluation of forty seven geotechnical boreholes and test pit logs was undertaken from borehole logs taken along the route of the proposed Brighton to Peacehaven pipeline in March 2006 (Green, 2006). The geotechnical work was conducted by Soil Mechanics Ltd on behalf of Mott Macdonald. The geotechnical data were subsequently collated and evaluated by ArchaeoScape (on behalf of RPS Consultants) with the aim of providing an indication of the range of sub-surface conditions likely to be encountered along the pipeline route and at the WTW site (Peacehaven).
Summary of the Results and Recommendations
A5.10 Along the route of the Brighton to Peacehaven pipeline: 2003. The results of the borehole and trial pit investigations at Rottingdean, Saltdean and Sheepcote indicated that there is no reason to undertake further palaeoenvironmental assessments at these sites. The investigations in the lower Ouse valley at North Quay and Brookside Farm did however produce extremely interesting records that
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provide significant potential for further palaeoenvironmental (including environmental archaeological) work. In particular, the evidence of peat development in the middle part of the Brookside Farm sequence (11.5m and 15m) provides an exciting opportunity to add to our understanding of Holocene sea level behaviour in the English Channel. It was recommended that if further work is to be undertaken at Brookside Farm and North Quay, continuous borehole samples (e.g. U100) should be obtained from the entire sedimentary sequence for laboratory analysis (Swindle et al., 2003).
A5.11 Along the route of the Brighton to Peacehaven pipeline: 2006. Sub-surface conditions along the proposed route were found to be variable but there was no evidence that deposits of highly significant geo-archaeological interest were present. In particular, it was concluded that the proposed works would not impact on the Black Rock Raised Beach or on any of the sediments or buried landforms associated with it. It was noted that several of the proposed shafts and adjacent portions of tunnel will be excavated in Quaternary sediments and/or weathered/disturbed chalk. Evidence of palaeoenvironmental interest may be present in these Quaternary deposits in the form of buried soils and plant or faunal remains. In addition the upper part of these superficial sequences may represent Holocene (post-Neolithic) hill wash. It was concluded the likelihood of such features coming to light in future excavations is however low or low to moderate.
Proposed Work: Updated Aims and Objectives
A5.12 Along the route of the Brighton to Peacehaven pipeline - It is proposed that ArchaeoScape will be ‘on-call’ to provide assistance and advice for the sampling, assessment and analysis of any deposits that may be uncovered during archaeological evaluation/excavation, and the construction of the pipeline. We propose to produce detailed, task specific costs as the programme of work progresses.
A5.13 It is proposed that ArchaeoScape will be ‘on-call’ to provide assistance and advice for the sampling, assessment and analysis of any deposits that may be uncovered during archaeological evaluations/strip and map procedures during the construction of the pipeline. Archaeoscape propose to produce detailed, task specific costs as the programme of work progresses.
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Project Tasks and \Activities
A5.14 Outlined below are the objectives of the environmental archaeological investigation; listed as tasks for completion in order to achieve the aims listed above. Each task has a specific activity, or set of activities. A member, or members, of ArchaeoScape, will complete each task and activity.
A5.15 Contingency for a ‘watching brief/advice’ and environmental archaeological assessment/analysis would be as follows:
On-site monitoring, advice and / or sampling of deposits - Dr. C.P. Green
On-site monitoring, advice and / or sampling of deposits R. Batchelor BSc
Descriptions of the sedimentary sequences - Dr. C.P. Green
Extraction of charcoal -K. Williams
Assessment/Analysis of charcoal - Gray MSc
Extraction of Mollusca - K. Williams
Assessment/Analysis of Mollusca - Prof. R. Preece
Extraction of charred seeds - K. Williams
Assessment/Analysis of charred seeds - Grey MSc
AMS radiocarbon dating of terrestrial plant macrofossil (seeds, fruits or wood) – Beta Analytic
Reporting preparation - Dr. C.P. Green
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References
Green, C.P. (2006) An evaluation of geotechnical borehole and test pit data from locations between Brighton and Peacehaven, East Sussex. ArchaeoScape Unpublished Report.
Green, C.P., Swindle, G.E., Branch, N.P., Palmer, A.P., Vaughan Williams, A., Austin P. and Keen, D. (2004) Environmental archaeological assessment: A reconstruction of the formation history of sub-surface sediments and soils within a dry valley at Peacehaven, East Sussex, UK. ArchaeoScape Unpublished Report.
Green, C.P., Swindle, G.E., Branch, N.P., Palmer, A.P., Vaughan Williams, A., Austin, P. and Keen, D. (2005) A reconstruction of the environmental history of a dry valley at Peacehaven, East Sussex, UK. ArchaeoScape Unpublished Report.
Swindle, G.E., Green, C.P., Branch, N.P. and Gale, R. (2003) Interim Environmental Archaeological Assessment: Proposed Brighton and Hove Waste Water Treatment Works. ArchaeoScape Unpublished Report.
Swindle, G.E., Green, C.P. and Branch, N.P (2004) A reconstruction of the formation history of subsurface sediments and soils within a dry valley at Peacehaven, East Sussex, UK. ArchaeoScape Unpublished Report.
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APPENDIX 6: SPECIFICATION FOR ARCHAEOLOGICAL
WATCHING BRIEF ON POTENTIAL PLEISTOCENE
DEPOSITS (MATT POPE - ARCHAEOLOGY SOUTH
EAST)
Geoarchaeological Background
A6.1 The locations of the various construction sites associated with the Brighton and Hove Wastewater Treatment Project are shown on Figure 1 of the main WSI. All have some potential to contain deposits of Pleistocene date within sink holes or at the base of dry valley sequences although only the Penstock Chamber at the marina hs any potential to contain Raised Beach deposits.
A6.2 The BGS Sheet 318 (1984) shows the site to be underlain by Cretaceous Chalk and Quaternary Head deposits. The latter can be readily seen in the Black Rock raised beach section, 100m to the north, and form a series of bedded colluvial deposits comprising red to pinkish silts supporting consolidated beds of sub-angular chalk and flint gravel. Some of these beds are orientated in relation to the remnant chalk cliff of the Brighton Raised Beach and will have bedding angles of up to 45 degrees orientated on a NE-SW axis. Others are of dry valley origin and will have generally horizontal bedding angles and form the fill of north-south oriented valley profiles.
A6.3 There is potential for palaeoarchaeological remains to be preserved at depth at the proposed development’s location. It is possible that, underlying the Head Gravels, terrestrial and marine deposits are preserved. These are likely to have important associated palaeoenvironmental material and may possibly preserve Palaeolithic artefacts. A possible basal marine sequence and wave-cut platform, perhaps associated with the Pagham Raised Beach, are thought to lie within the maximum depth of intrusive ground works. Historic records show that, in the wider area, a
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preserved palaeolandsurface may be encountered that might include organic and faunal remains.
Aims
A6.4 The general objective of the archaeological work is to monitor the groundwork in order to ensure that any artefacts or ecofacts of archaeological and palaeoarchaelogical interest exposed and affected by the excavations are recorded and interpreted to appropriate standards.
A6.5 The following intrusive groundworks will be monitored by an archaeologist.
• Penstock chamber
• Any other significant intrusive groundworks associated with the scheme (particularly shaft sites)
Methods to be used
A6.6 New ground works excavations undertaken by engineering contractors will be monitored on approximately a one day per week basis (or as required) by an archaeologist until/unless it becomes clear beyond reasonable doubt that no archaeological remains/significant geoarchaeological deposits are present (e.g. once excavation reaches undisturbed natural Cretaceous geology, below which there will be no archaeological remains present - after the recording of any significant remains if present at higher levels).
A6.7 Where new excavations reveal significant archaeological material or palaeoarchaeological deposits, an opportunity will be made for the collection of samples, and these will be hand excavated and recorded to archaeological standards by the archaeologist in attendance. Exposures will be hand cleaned by
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archaeologists if safety allows. Adequate time will be made available for appropriate archaeological excavation by hand to identify and record the remains as far as possible within the limits of the works in order to extract archaeological and environmental information, should this prove necessary.
A6.8 This will enable any archaeological deposits, disturbed during the proposed works, to be adequately recorded in line with the advice given in PPG16 (the Government’s advice on Archaeology and Planning) and policy HE12 of the Brighton and Hove Local Plan.
A6.9 Where possible the spoil from the excavations will also be inspected by archaeologists to recover any artefacts or ecofacts of archaeological interest.
A6.10 The County Archaeologist, ESCC will be kept informed of progress so that he may monitor the archaeological work or inform the Local Planning Authority (LPA) of developments as necessary.
A6.11 All archaeological features will be recorded according to standard UCLFAU practice. Where practicable, all features will be planned at 1:20 and section drawings will be at 1:10. Drawings will be on plastic draughting film. Features and deposits will be described on standard pro-forma recording sheets used by UCLFAU. All remains will be levelled with respect to Ordnance Survey datum. A photographic record will be made in both monochrome and colour transparency.
A6.12 Pleistocene Sediments will be recorded in the following manner. Beneath the modern horizons, the running section will be recorded at 5m horizontal intervals to allow the development of a series of detailed sediment logs. These will comprise detailed sediment descriptions at 0.25m intervals or at the junction of major stratigraphic or
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lithological boundaries. The descriptions will comprise matrix lithology, coarse components, sediment cohesion and well as characterisation of superficial structures and likelihood of decalcification. Given the presence of depositional contexts likely to preserve either artefactual or macrofaunal material at depths which are below the possibility of direct in-situ inspection, the arisings will be placed in stratigraphical order to enable description and recording. During excavation dry sieving of such contexts, where possible, will take place to look for lithic artefacts. In conjunction with the sieving, the spoil will be constantly checked for artefacts as the trench is dug.
A6.13 Should in situ Palaeolithic archaeology be encountered, work at the location should temporarily cease until an appropriate mitigation strategy has been rapidly developed. Fine-grained deposits will be sampled and assessed for vertebrate and invertebrate microfauna and palynological analysis.
A6.14 Given the depth of stratigraphy composite geological sections will be drawn at 1:20: samples will be given a unique running number and marked on the section drawings. Sediment chromas and hues will be recorded using a Munsell Soil Colour Chart. Continous section photography will be undertaken if at all practical.
A6.15 If deposits suitable for environmental sampling are encountered (such as dated excavated contexts of buried soils, well-sealed slowly silting features, sealed hearths, sealed features containing evident carbonised remains, peats, water-logged or cess deposits), bulk soil samples (40 litres or 100% of smaller features) will be taken for environmental analysis. In the case of sediments suitable for either pollen, coleopteran or micropalaeontogical analysis, sediments will be closely sampled at <50mm intervals from vertical, closely recorded columns. Palaeosols will be sampled using sediments tins which will allow for subsequent soil micromorphological analysis should it be deemed necessary.
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Treatment of Human Remains
A6.16 If human remains are found, work will cease and all necessary statutory provisions followed. Geoff Bennett, BHCC and Casper Johnson, ESCC will be informed immediately.
Treatment of other Artefacts and Ecofacts.
A6.17 Worked flint, faunal remains and other finds of archaeological significance will be retained and treated according to standard Archaeology South-East procedures. Identification of retained finds will be undertaken by staff of, and specialists contracted by, Archaeology South East as necessary.
A6.18 Bulk samples will be processed using tank flotation unless considered detrimental to the samples or recovery rate (such as for waterlogged samples). Bulk samples will target recovery of plant remains (charcoal and macrobotanicals), fish, bird, small mammal and amphibian bone, and small artefacts. Waterlogged samples will be wet sieved through nested sieves and stored in wet, cool conditions or dried if considered an appropriate form of conservation for the remains. Specialist samples may also be taken from dry or waterlogged contexts. Such samples will target recovery of pollen (using monolith tins), molluscs, foraminifera, parasites and insects. Larger samples (80-100 litres) will be extracted wholesale from deposits rich in marine molluscs and large mammal bones. As a general rule waterlogged wood specimens will be recorded in detail in their original location. If removed they will be cleaned, photographed and a thin section sample will be taken for identification. Specimens will either be stored in wet cool conditions or dried if considered appropriate for the material. In all instances deposits with clear intrusive material shall be avoided.
Reporting and Archive
A6.19 If the results merit, a post-excavation assessment report will be prepared, and a programme of post-excavation analysis and reporting along the lines recommended
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in Management of Archaeological Projects (English Heritage 1991) will agreed with the client and the relevant authorities.
A6.20 If it is agreed that the results do not merit the full procedure described in A6.19 above, a report will be prepared describing the site and the work undertaken, and giving sufficient archaeological and historical information to adequately understand the archaeological results. It will discuss previous archaeological work in the area as relevant. The report will describe the archaeological features and finds, with specialist description and comment as necessary. Plans and section drawings showing the location of the site and the works, and details of any features, will be included. Interpretative drawings and discussion will be included as necessary.
A6.21 A draft copy of the report will be sent to the County Archaeologist, East Sussex County Council in the first instance for his comments and approval. Once the report has been accepted and ESCC have recommended to the Local Planning Authority that the relevant planning condition should be discharged, further copies will be sent to ESCC and the client as appropriate. A short summary of the work will be prepared for the relevant local archaeological journal.
A6.22 A further digital copy of the report (including plans, illustrations and photographs) will be supplied to the East Sussex Historic Environment Record on CD-ROM in a .pdf format.
A6.23 The written and drawn archive will be deposited in an appropriate museum. Artefacts and ecofacts recovered during excavation form an important part of an archaeological site archive. Permission will be sought from the landowner to donate the finds from this project to an appropriate museum for deposition with the rest of the archive. The archive will be prepared according the principles of Management of
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Archaeological Projects (English Heritage, 1991) and the requirements of the recipient museum.
Health and Safety
A6.24 A risk assessment will be prepared before the commencement of fieldwork. All relevant legislation will be followed.
Insurance
A6.25 Archaeology South East is insured against claims for: employer’s liability to the value of £25,000,000 each and every loss; primary public/products liability to the value of £10,000,000 any one occurrence and in the aggregate for products liability, with an extension for no-fault compensation up to £10,000,000 in the aggregate; professional indemnity to the value of £10,000,000 any one occurrence.
Time Table and Project Management
A6.26 The construction is envisaged as taking some months. It is proposed that approximately one day per week be allocated during this time to monitor this work, with two further days allocated as a contingency to cover any over run of the construction phase.
A6.27 This project will be managed by Neil Griffin (fieldwork) and Louise Rayner (post- excavation).
Archaeology South-East
14th July 2008
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