Archaeological contractors

Introduction

The NPPF places the responsibility for dealing with heritage assets affected by development proposals with the developer. Local planning authorities will need to be assured by those applying for planning permission that any such remains are not under threat. As a result developers are required to produce a definitive method of mitigating the effect of development on the historic environment within the planning process. Often it will have been necessary to undertake archaeological work in advance of the planning application being considered to ensure that the local planning authority has been fully informed when coming to a decisions about the proposed development and its impact upon heritage assets. In Lincolnshire archaeological advisors will issue appropriate guidance and advice to aid developers in the fulfilment of their archaeological responsibilities.

The brief

In the majority of cases it will not be necessary for a brief to be produced by the archaeological advisor. If one is required for a particular project it will set out the basic requirements of the project and the standards which are to be adhered to while it is being undertaken. The brief will contain sufficient detail for the developer to use the document to initiate a tendering process. The specifications, or written project designs produced on behalf of the developer must then be reviewed by the archaeological advisor, acting on behalf of the local planning authority. This will ensure that the proposals fully meet the requirements set in the brief. Any documents not deemed to fulfil the brief will be identified to the developer and rejected.

The Written Scheme of Investigation

The responsibility of the developer is to commission an archaeological Written Scheme of Investigation, or project design, from an archaeological contractor. The archaeological contractor will need to be aware when negotiating with the archaeological advisor and/or giving advice to their client of their dual responsibility, the archaeologist will be considered to be acting in a consultancy role. The archaeological contractor or heritage professional should discuss the detail of the Written Scheme of Investigation or mitigation strategy with the archaeological advisor to agree the scope of works prior to submission to the local planning authority for formal approval and discharge of the relevant condition. This document must put forward suitable methodologies and intended timescales.

Mitigation strategy

A Mitigation Strategy is a statement as to how the developer intends to mitigate the effects of proposed development on any heritage asset. This may involve the production of a Statement of Significance and/or a Heritage Impact Assessment. Such a strategy should describe the methodology for mitigation by preservation or recording. The strategy might provide for preservation in situ of any archaeological remains, either by designing a scheme which leaves a particular significant area undeveloped (such as retained green space) or by designing shallow foundations which might override sensitive remains. On the other hand, it may provide for recording archaeological remains prior to destruction by the development; such strategies would normally be accompanied by the submission of a programme of archaeological works (the Written Scheme of Investigation). These should always be produced in consultation with the appropriate local authority archaeological advisor.

The content of the written scheme of investigation (project design)

Introduction

This section sets out the expected content of a Written Scheme of Investigation or project design following input from the local authority archaeological advisor. In order that the archaeological advisor will have sufficient time to ensure the suitability of the specification, and also to allow time to arrange any required monitoring of the subsequent works, the specification should be approved at least ten working days prior to the intended start date of works. The specification should be provided in an appropriate digital format.

Background to a Written Scheme of Investigation or project design

The Written Scheme of Investigation should address the issues raised within the brief. It should provide sufficient detail to indicate exactly how information will be gained for planning purposes. In preparing the Written Scheme of Investigation it should be borne in mind the need for minimum archaeological intervention and for work to be carried out in the most efficient way. Outlined below are the sections which will normally be expected within a Written Scheme of Investigation (please refer to the appropriate CIfA Standard and Guidance for detailed requirements).

General contracting arrangements

In addition to the detail required of a Written Scheme of Investigation as laid out below the archaeological advisor will need to be assured of the suitability of the contracting unit. To this end the Written Scheme of Investigation must include a list of key personnel along with details of their relevant experience and a curriculum vitae for each specialist member of staff, if appropriate.

The contents of a Written Scheme of Investigation

During the production of the Written Scheme of Investigation all relevant specialists should be consulted. The specification should consist of the following sections.

Title page

This should include the site name, address and OS grid reference, the client's name, the date (month and year) and the contractor's name. Note the approved Written Scheme of Investigation should include the planning reference number, site code and museum accession number (where appropriate).

Non-technical summary

This section should be an overview of the contents of the Written Scheme of Investigation in plain language.

Site location and description

The Written Scheme of Investigation or project design should contain a site plan (1:10000 scale or larger) and a location plan (1:50000 or 1:25000) as well as the OS grid reference. The site grid must be tied into the national grid. Details of site or area geology, land-use, altitude, soils and vegetation should also be given, as well as any physical and environmental constraints on the proposed works.

Planning background

The specification or project design should outline the planning issue, in particular the stage within the planning process and the nature of the development. There should also be an indication of any planning constraints worthy of consideration, for example:

scheduled monument
conservation area
national landscape
site of special scientific interest
listed building
tree preservation order
requirements for biodiversity net gain

Archaeological and historical background

The Written Scheme of Investigation or project design must contain a summary of the known archaeological information relating to the site and its vicinity. This should contain data from the county HER, any previous research (for example, a desk-based assessment) and other relevant sources.

Aims and objectives of the project

In response to the brief's requirements for work, every archaeological project should have a clear statement of objectives. This should be set within the appropriate archaeological national, regional and local research frameworks.

Methodology

The Written Scheme of Investigation will be expected to contain a reasoned discussion of the field and analytical techniques selected. Details must be given of techniques, artefact collection policies, discard policies, environmental sampling strategy and recording techniques. The modification or rejection of a standard technique should be explained in a statement of justification. Prior to submitting your draft Written Scheme of Investigation please cross-check it with the CIfA Standard and Guidance.

Post-fieldwork methodology

The Written Scheme of Investigation should contain an explanation of the proposed post-fieldwork techniques to be utilised. Details must include, but are not limited to, cleaning, conservation, cataloguing, packaging, dating techniques, publication and archive preparation. For environmental samples the proposed methods of processing and storage should also be given. Where used, specialists are to be listed.

Public engagement

The Written Scheme of Investigation should set out proposals for public engagement and involvement appropriate to the scheme.

Monitoring arrangements

The Written Scheme of Investigation must include arrangements for monitoring by the relevant archaeological advisor and allowing for a minimum of 14 days’ notice for the planned commencement date of fieldwork.

Archive preparation and deposition

The specification should include an indication of the level and format of the archive to be produced. The Written Scheme of Investigation should state where it is proposed to deposit the physical archive and arrangements for uploading the digital record to the Archaeological Data Service. The archive should be deposited within six months of the project completion. It is recommended contractors contact the relevant museum to obtain an accession number and to confirm arrangements for the archive deposition. This requirement must be included in the Written Scheme of Investigation and the archaeological advisor regularly updated on the project’s progress. Where appropriate contractors are expected to arrange formal review meetings with the archaeological advisor.

The archive consists of all digital records and materials recovered, drawn and photographic records, including a single copy of the final report. It will be quantified, ordered, indexed and internally consistent. It should also contain site matrices, a site summary and brief written observations on the artefactual and environmental data.

If the receiving museum is to be Lincoln Museum then the archive should be produced in the form outlined in that museum's document 'Conditions for the Acceptance of Project Archives'. You can contact Lincoln Museum by emailing lincolnmuseum@lincolnshire.gov.uk.

It should be noted that the archaeological advisor will not recommend the discharge of any planning conditions until they have approved the report and the archive has been deposited.

Reporting procedures

The Written Scheme of Investigation should outline the proposed reporting procedure and the likely timetable, as well as the anticipated content of the final and any other reports. This should be informed by relevant professional standards as well as guidance from Historic England and other specialist bodies.

Publication and dissemination

It is important that results of archaeological investigation reach the public domain and this matter should be addressed within the Written Scheme of Investigation.

Contingency arrangements

It will be necessary to provide contingency arrangements, particularly for unexpected discoveries. The Written Scheme of Investigation should provide recognition of the procedures laid down to initiate any contingency plans.

Health and safety

The Written Scheme of Investigation should include details of the health and safety policies in place, relevant risk assessments and confirmation that appropriate insurance is in place.

Copyright

The Written Scheme of Investigation will need to verify that agreement has taken place over the ownership, transfer of title and copyright.

Archaeological methodology

Introduction

The next major consideration in project design is the selection of field techniques and the anticipated method of on-site working. The following is a summary of matters to be borne in mind when undertaking a project. Some of these are relevant only to one form of historic environment work whereas others may apply to a number of different types of historic environment project.

Background

Those undertaking historic environment projects have an obligation to carry out that project to a professional standard. This standard ensures that sufficient information is provided by the project for planning purposes and that reporting and archiving meet the requirements of the receiving HER and museum. Guidance on standards of historic environment work has been issued by various bodies including Historic England, ADS and the CIfA.

Site location

All historic environment fieldwork must be subject to adequate horizontal and vertical survey control. The location of the grid will be established, relative to the OS national grid. In most instances it will be expected that control points and trenches will be surveyed using an EDM or GPS (Global Positioning System). The GPS equipment which is use should be accurate to the sub-centimetre level (differential GPS). The vertical survey control will be tied to the Ordnance Datum. The accuracy must be of a level to allow the work to be repeated by a third party.

Consideration of techniques

When preparing a project design, and/or specification, account must be taken of the local geology, topography and land-use as it affects the feasibility of the various techniques. Consideration should be given to additional aerial survey, lidar, field-walking, earthwork survey, geophysical survey and the observation of geotechnical test-pits (if appropriate), as well as the undertaking of archaeological test-pits, as possible field evaluation techniques.

Earthwork survey

Earthwork surveys may form part of a pre-determination evaluation or a post-determination mitigation strategy. They should not normally be carried out at a scale less than 1:500 and using an agreed methodology appropriate to the site’s location and size.

Fieldwalking

Fieldwalking is essentially a technique used for prospection during the field evaluation of a rural site. Such a reconnaissance survey can be carried out on transects spaced 10 to 20m apart. Surface material can also be collected to give a more detailed indication of likely buried remains at a finer scale. Both levels of fieldwalking should only be carried out in conditions of suitable ground visibility which would normally be after the land has been ploughed, harrowed and left to weather for an appropriate length of time.

Geophysical survey

Archaeological geophysical survey should be undertaken in accordance with current guidance (EAC Guidelines).

Environmental evidence

Environmental evidence is a necessary and potentially important element of the archaeological record. During a field evaluation an accurate assessment of the preservation of environmental evidence, including animal bone, shell, waterlogged and charred organic remains, and the condition of any buried soils and sediments should be made. This assessment should be sufficiently comprehensive to allow an evaluation of its potential archaeological relevance and to enable the construction of a structured sampling strategy and post-excavation programme, should the evaluation go to the full excavation stage. When undertaking this work advice must be sought from an appropriate environmental consultant or from Historic England Regional Science Advisor. Environmental sampling should be undertaken according to current Historic England guidance.

Trial excavation

Excavation is a potentially destructive evaluation technique and, where possible attempts must be made to maximise data retrieval from non-destructive techniques before undertaking excavation. However, should trial excavation be required the specification should include a detailed reasoning for the application of the technique.

Whether excavation is being undertaken as part of a pre-determination evaluation or as part of a mitigation strategy the following factors should be borne in mind:

all machine work should be supervised by an experienced archaeologist
machining should stop at the first archaeological horizon
the use of an appropriate machine with a wide, toothless ditching blade, when archaeological features are revealed these will be cleaned by hand
a representative sample (as agreed with the planning archaeologist) of every archaeological feature must be excavated by hand (although the depth of surviving deposits must be determined, it is not expected that every trench will be excavated to natural)
adequate recovery of finds and an appropriate sampling programme to provide environmental evidence from all archaeological deposits should be ensured. A site visit by the nominated environmental specialist may be required
where appropriate, a level of science advice either from the Historic England Regional Science Advisor or an appropriate specialist should be sought
if human remains are encountered these would normally be left in-situ
It is expected that an acceptable recording system will be used for all on-site and post fieldwork procedures. The recording procedure must take into account the long-term archival requirements of archaeological records. Due attention must be given to the drawn and photographic record. Both artefacts and ecofacts must be handled according to the requirements of the document Conditions for the acceptance of archaeological archives (produced by The Collection, Lincoln and reproduced here). Prior to fieldwork commencing discussions should take place with The Collection, or any other receiving museum regarding archive deposition. At this time an accession number will be issued and should be used throughout the project.
All faces of the trench which require examination should be cleaned using hand tools. All investigation of archaeological deposits will be by hand. Cleaning, examination and recording should take place in both plan and section.
The objective of any excavation within a field evaluation programme should be to define remains rather than totally remove them. Excavation should normally be limited to the minimum necessary to characterise the value or potential of the remains.
As well as the excavation or sampling of archaeological features it may be necessary to examine naturally deposited material. Such layers may contain environmental material.
When the decision has been made that archaeologically significant remains warrant preservation in situ, suitable arrangements must be made to prevent their deterioration. The area to be preserved should be clearly defined, fenced off and a suitable preservation strategy produced.

Test pitting

A further prospection technique is that of test pitting. Test pitting is not to be used instead of trial excavation, which is the preferred method of evaluation; however it may be used in exceptional circumstances. This will consist of the excavation of trial pits (normally 1.5 by 1.5m) on a regular pattern such as for example, a 50m grid. Full details must be agreed in detail with the planning archaeologist. The general standards and methods of work should conform to those for trial excavation as outlined above.

Building recording

In undertaking building recording reference should be made to CIfA and Historic England’s guidance for advice on the appropriate techniques to be used. It should be remembered that each project is unique and often a mixture of levels may be required. As a minimum each report must contain some level of written account, drawings and photographs.

Use of specialists

For the smooth running of an archaeological project it is essential that close liaison takes place between the archaeological contractors and their specialists. This would be of particular value when specialist advice might be needed, for example, if a fragile find requires lifting or environmental samples are to be taken.

Recording systems and artefact handling

The interpretation of data from any given historic environment project can only be maximised if their retrieval is recorded thoroughly. Knowledge of past activity as represented by the archaeological record can only be understood through the stratigraphic sequence. The physical relationships between archaeological contexts can only be determined after detailed recording and analysis. Single-context recording as developed by the Museum of London Archaeology Service (MoLAS) should be followed.

Recording systems

Before fieldwork starts it is essential that provision is made for long term storage of the subsequent archive. It is highly desirable that archaeological material is deposited in a museum which has expertise and resources to adequately provide for long-term storage and survival. If this is not to be the case the planning archaeologist will expect to be assured that other suitable arrangements are being made (see chapter 17).

Lincoln Museum

The main archaeological museum in Lincolnshire is the Lincoln Museum in Lincoln. Dates of deposition of archival material in the museum must be agreed prior to commencement of work, and the deposition date must be included in the specification written by the contractor. The contractor will be provided with a museum accession number where appropriate. For further information on archive deposition contact lincolnmuseum@lincolnshire.gov.uk.

Requirements

a unique site code must be agreed with the Lincoln Museum, Lincoln and an accession number provided if this is to be the recipient museum
the site archive should be produced to be compatible with the requirements laid down by Lincoln Museum
utilising a Harris-Winchester or similar matrix for complex stratigraphical problems
the production of a suitable photographic record
the use of terminology and type series coding consistent with those already in use in Lincolnshire, if national codes are being used then these should be cross-referenced to the existing codes used in Lincolnshire (for details of Lincolnshire type series and coding contact Lincoln Museum)
a digital copy of the report must be deposited with the HER. This should be in the form of a single PDF/A. This will not be counted as an archived dataset and if there is a need to archive digital data in perpetuity then contractors should discuss their requirements with Lincoln Museum and with the Archaeological Data Service (ADS)

On-site artefact handling

All staff, including all sub-contracted specialists, involved with a project must be made aware of First Aid for Finds, Society of Museum Archaeologists guidelines and other related documents (see Resources) and should follow the procedures listed therein. Of particular value to those managing archaeological archives both on-site and in long-term storage are these publications from Historic England. It is imperative that the implications of these documents are noted at the tendering stage of any project because they have both practical and financial implications. Advice on the handling of all archaeological materials can be provided by the staff of Lincoln Museum. In particular the advice of the museum's conservation staff will be of value when handling sensitive materials.

Processing

Bulk finds

All bulk finds will be washed, dried, marked (as appropriate for each material) and packaged according to the standards set out by Lincoln Museum.

Registered finds

All registered finds (small finds) should be processed and packaged according to standards of good practice. All such finds should be submitted for X-radiography and stabilisation where appropriate according to the standards set out by Lincoln Museum.

Samples

All samples must be labelled according to type (for example, industrial, environmental) and the reason for their retention clearly specified. Arrangements should be made for the processing of all samples during the excavation or at the assessment stage and any submitted to the museum must have been prepared for long-term storage. Certain types of samples may be retained in specialist research laboratories.

Basic record

A paper and computer record should be created for all the documentary archive which relates to finds and their analysis. The minimum level of recording for each category is given below.

The following is the minimum amount of information that should be recorded for each context following the terminology and coding system used in The Musuem Collection Thesaurus:

site code and accession number;
context
category
count and weight
comments, if appropriate

For pottery and building material, the following is the minimum amount of information that should be recorded for each context:

site code and accession number
context
date range
fabric code or detailed fabric description
diagnostic forms
condition of group, where appropriate (for example, smashed, burnt, abraded)
obvious cross joins to other contexts
sherd count and, or weight in grams
suitability for illustration, if appropriate
decoration, if appropriate
comments, if appropriate

For registered finds, the following is the minimum amount of information that should be recorded for each object following the terminology and coding system used in The Musuem Collection Thesaurus:

site code and accession number
context
registration number
material
object description
the X-radiograph number
dimensions or preferably an accurate sketch drawing
comments, if appropriate

For samples, the following is the minimum amount of information that should be recorded for each sample:

site code and accession number (sample number if appropriate)
context
sample type
weight and volume
comments

The finds report

A finds report should accompany all finds deposited with Lincoln Museum. The report should include all the following points:

statement about the condition of the material recovered, noting whether site conditions may have been favourable or precluded the preservation of certain materials
statement on how the finds were collected and any value or bias that the collection and sampling strategies may have created should be noted
statement on any dispersal policy (this must be pre-arranged with the museum) and a list of material to be considered in the five yearly review
statement concerning the potential of the finds both to answer site based questions, regional research topics and problems intrinsic to the finds themselves
statement outlining key objects or groups
quantification of the data broken down into the major stratigraphic units of the site, if appropriate
list of all the finds by material, not just ceramics
list of all staff and specialists involved in the project
list of displayable objects and reasons for selection
recommendations for long term curation and storage, highlighting any particularly vulnerable items
the conservation report and all associated records, if any active conservation work has been undertaken
statement regarding any further work that should be done (academic or curatorial), to include any material that could be considered for dispersal in the five yearly review

The finds archive

At the end of the project the artefact element of the site archive should consist of the following:

the finds themselves correctly boxed, packaged and labelled
the basic documentary record (including a microform and computerised copy)
the X-radiographs
a finds report
any drawings, photographs (prints and, or slides) and illustrations
a statement of the number and sizes of boxes in which the different categories of finds are stored
all samples stored in specialist laboratories should be listed along with the full address of the laboratory and a description of the sample type
a list of all codes used with a full expansion

Specialists

Specialists working in Lincolnshire

Established specialists new to working in Lincolnshire should demonstrate competency through appropriate qualifications, peer-reviewed publications, curriculum vitae and academic references, these should all be submitted to the appropriate planning curator. Any specification for archaeological work naming such a specialist will not be approved until the above has been verified.

Specialists who are undergoing training with a suitable qualified mentor are able to work in Lincolnshire. Details of their curriculum vita, references, training and mentor details should be submitted to the archaeological curator.

All specialisms are equally important and whilst not all are covered in the same detail in this chapter of the handbook further details may be sought from the respective specialists. It is intended that this section be expanded by the relevant specialists.

Pottery specialists

Pottery codes

To ensure continuity of practice and build upon existing knowledge and expertise it is important that all pottery uses the same ceramic codes names. Working with such a standardised framework enhances our understanding of ceramic production and use within the county as well as facilitating identification of issues of local and national importance All pottery should be coded using the national type series, where existing, and should be accompanied by a concordance table with any local pottery type series (contact Lincoln Museum for details).

Finds that are not covered by any existing type series and coding systems or are only covered by generic codes, should be given fuller descriptions.

Lincolnshire type series

Great advances have been made in the understanding of the ceramic sequences in Lincolnshire over the last thirty years but much of this knowledge remains in ‘grey literature’ although the Roman and Saxon to medieval sequences are published. Ceramic specialists who have not worked extensively within the county are advised to consult the HER for individual site reports for the areas in which they are working.

The pottery found in Lincolnshire is complex, for example there are currently 28 individual medieval pottery (twelfth to fifteenth century) zones identified in Lincolnshire alone, so it is recommended that all specialists, particularly those not regularly working in Lincolnshire should make use of the Finds Type Series in order to accurately identify ware types.

The Finds Type Series for Roman and Post Roman ceramics is held at Lincoln City and County Museum (The Collection) and can be viewed by appointment.

Lincoln Museum
Danes Terrace
Lincoln
LN2 1LP
01522 782 040

A Rural Kesteven Type Series is held by Heritage Lincolnshire and can be viewed by appointment.

The Old School
Cameron Street
Heckington
Lincolnshire
NG34 9RW
01529 461618

An additional Finds Type Series, more specific to North Lincolnshire, is held in North Lincolnshire Museum.

Oswald Road
Scunthorpe
North Lincolnshire
DN15 7BD
01724 843533

The specialists who regularly work in Lincolnshire are also happy to discuss any issue relating to work that may be undertaken by any other specialist, especially those without the same amount of local experience.

National guidance

Every specialist should be aware of their own national guidance. This guidance should be followed when producing work in Lincolnshire. All work should be placed within its local and regional context and should refer to both local and nation research objectives.

Human and faunal remains

Before the exhumation of human remains takes place, a licence from the Ministry of Justice must be obtained. Dependant on the type of burial: graveyard, lone burials, religious affiliation or age of burial different acts of law apply, the Ministry of Justice will advise and ensure that the appropriate license is applied for.

Analysis of human and faunal remains should be undertaken by a trained osteologist or zooarchaeologist respectively.

Registered small finds

In order to ensure that finds are recorded to a common standard, specialist reports on registered small finds should adhere to the agreed term-lists for materials and object-names set out by the SPECTRUM standard. Registered small finds should, where possible, be referenced according to current accepted typologies and, or published catalogues (for example Roman Imperial Coinage (RIC) for Roman coins; Bruce-Mitford (2005) for hanging-bowls), and include a discussion of their local, regional and national significance as considered appropriate.

Conservation work

Commissioning conservation work

When presenting an assemblage for a conservation assessment it is helpful if a specification for the level and type of work required is provided rather than just for example, a request to assess for ‘conservation’. Conservation is a discipline, not a specific task – the level of work required and therefore the tasks needed, will vary dependant on the project requirements.

Conservation work required within the planning and development context is likely to fall into the following areas:

Basic minimum requirement to enable deposition

This will normally involve:

packaging to provide physical support necessary for long term storage
packaging to provide necessary environmental control for long term storage
remedial treatment of actively deteriorating objects
X-radiography to clarify obscured morphology
all tasks that are likely to need to be commissioned from a suitably qualified conservator (and in the case of any direct intervention on an object, it will be essential) who will have the necessary expertise to assess an assemblage against these criteria

Completion of these tasks will ensure ‘stabilisation of the assemblage to confer a level of long-term integrity to it’ and ‘investigation of finds to clarify morphology’ as specified by Lincoln Museum. If the level of work required is not clearly specified to the conservator (especially if they are non-local and not familiar with LCC’s guidelines), it may result in either difficulties during handover if essential criteria are not met, or in unnecessary work being carried out.

When this level of work has been completed and the assemblage is returned, at this point the archive is ready for transfer to the museum store, however if there is a delay before hand-over and environmental control is not maintained, deterioration will almost certainly occur which will need to be remedied before the assemblage will be accepted for deposition.

Further investigation

If specialist reports recommend further investigation of finds, ensure the specialist clearly explains the issue that requires investigation and that full details of the query are passed on to the conservator, rather than for example just a list of items selected ‘for conservation’. Further investigation could involve a number of techniques including further investigative x-radiography or other analytical technique or investigative corrosion removal in the specific area of interest, depending on the actual query. If adequate information from the specialist is not provided it may not be possible for the conservator to make an accurate assessment of the work needed.

Aesthetic improvement

Improvement of the appearance for aesthetic reasons (commonly referred to as ‘full cleaning’ or ‘display level conservation’) is normally only required for advocacy purposes, for example, for museum-type displays and is less likely to be a requirement within the planning and development context and much more likely to be something the receiving museum would consider once the finds have been deposited. A project might occasionally involve this level of work prior to deposition for, for example, a public event. The term ‘full-cleaning’ can be misleading even in this context as there can still be options for the level of work undertaken depending on the specific project requirement. A discussion with the conservator will enable them to advise appropriately.

Scheduling

It is worth contacting the conservator as early as possible before conservation work is needed to discuss requirements and scheduling. Some conservation work is time-consuming and, or requires a long treatment period (for example, treatment of waterlogged wood that can take weeks or months of treatment to stabilise it). It may not be possible to fit work in immediately if a conservation practice already has other commitments, particularly if no prior notice is given.

Monitoring in practice

Introduction

To ensure that any controlled archaeological work, such as that required by the planning process, is being carried out in accordance with the agreed project design, monitoring of fieldwork and post-fieldwork analysis will be required. Controlled work includes work by statutory undertakers, through agri-environment schemes, work done under ecclesiastical exemption or by the Ministry of Defence as well as work that has come through the planning process. In the following paragraphs the reference is to the planning process but it applies to all controlled archaeological work.

Background

Increasingly it is becoming necessary for all stages of the archaeological project to be monitored as it takes place. The aim is to ensure that the work is being carried out in accordance with the specification and in a way that will satisfy the requirements of the planning authority. It will also prove mutually beneficial for there to be an ongoing dialogue between the planning archaeologist and the contractors in the field. The final monitoring points will be to ensure that an appropriate report and archive have been deposited. Until this has been achieved, the developer will not be considered to have fulfilled the requirements of the planning permission.

General principles

Monitoring should be arranged to satisfy the CIfA standards. The archaeological monitors, usually the planning archaeologists, are not liable in any way for the failings of the contractor and such monitoring is not intended to take the place of proper self-regulation. The importance of self-regulation cannot be overstated. It is the contractor's responsibility to his client to ensure the planning requirements imposed upon the developer are met, in accordance with the brief and specification.

Monitoring principles

The aims of the monitoring should be to ensure that:

all critical aspects of the programme of archaeological works are undertaken to the satisfaction of the local planning authority
all aspects of the work are undertaken in accordance with the agreed specification
variations to the specification shall be agreed with the planning archaeologist in writing prior to them being carried out

It will be necessary to make arrangements for the monitoring prior to work commencing. In order for the planning archaeologist to timetable monitoring into each archaeological project they will require at least ten working days’ notice prior to the commencement of the work. In the discussions between planning archaeologist and contractor the following points will be relevant:

nominating representatives of the planning authority to carry out the monitoring
arranging access to the site for specialists appointed both by the planning authority and the contractor
establishing smooth lines of communication between the planning archaeologist, the contractor, consultant and developer, as appropriate
creating a project timetable with monitoring visits accounted for

Aspects to be monitored

Some points are of particular relevance when monitoring an archaeological project and these are outlined here.

The monitor will wish to confirm that excavation trenches and other interventions are located according to the agreed project design.

The monitor will need to be satisfied that the first archaeologically significant horizon has been correctly identified and no information has been lost by inappropriate use of a mechanical excavator.

The monitor will wish to assure him/herself that the project design is being followed in an appropriate way.

As the planning archaeologist with responsibility for advising on preservation in-situ, the monitor must be involved in any matters relating to on-site decisions regarding the conservation of remains.

At the end of the fieldwork phase the monitor will wish to be assured that:

the project design has been adhered to or altered only with his/her agreement
satisfactory arrangements have been made for any remains to be preserved in-situ
arrangements are in hand for backfilling the trenches and for returning the site to a condition acceptable to the planning authority and the developer

During the carrying out of a given project the monitor may make an unannounced site visit. By doing this he or she will aim to ensure that:

work is proceeding in accordance with the agreed project design
the production of the necessary site archive is taking place in a satisfactory manner

The monitor’s task will not be complete until a copy of an appropriate report has been approved and deposited with the HER and an acceptable archive has been deposited in the appropriate archiving facility.

Reporting

There will be three aspects to reporting the monitoring of fieldwork.

The monitor will make a verbal report on-site during his/her visit and amendments to the agreed project design may be made (subject to the developer's approval).

The monitor may produce a written report, which will be circulated to all relevant parties.

Sometimes a planning condition may be breached in a way that requires enforcement action. In such cases the monitor will notify the local planning authority pending enforcement action.

Contingencies

Introduction

This section outlines the responsibilities and the procedures to be followed in the event of unexpected discoveries being made during an historic environment project.

Background

Many of the procedures outlined in this document rely on the decisions made on currently available evidence. This evidence may be incomplete. Contingencies will be necessary to deal with unexpected discoveries, as it will not always be possible to absorb the extra work needed within the originally allocated resources.

The responsibility of the archaeological contractor

In all cases it is the responsibility of the archaeological contractor to inform all interested parties of any new or unexpected circumstances which arise during the project, whether or not the site is being monitored regularly. No decisions should be made as to an appropriate alteration to the project without the agreement of the planning archaeologist and the developer. This is particularly important when there are archaeological and, or financial implications.

Contingency

Both the planning archaeologist and the contractor should endeavour to identify any likely circumstances that might arise during the project that will result in costs over and above the expected cost of the project.These contingency costs should be quantified on the brief and, or the specification. It will be the responsibility of the planning archaeologist, on behalf of the local planning authority, to decide whether conditions on site allow for the use of a particular contingency but a contingency should only be implemented with the agreement of all interested parties. Final instructions should be made in writing to the developer on behalf of the local authority.

Discovery of remains during development

If, during the course of development, archaeological remains come to light for which no contingency has been made and which are not of national importance, then the planning archaeologist may wish to open discussions with the developer, on behalf of the local planning authority, to provide for the preservation or recording of those remains. The developer will not normally be under an obligation to provide further resources but will be expected to comply with all reasonable requests to ensure the recording or preservation of the remains.

An exception to the above will be where human remains are uncovered. In this case the developer will be responsible under the Burial Act (1857) for the excavation and removal of those remains.

Where remains are deemed by the Secretary of State, on the advice of Historic England, to be of national importance, in accordance with published criteria, then the Secretary of State has the power to legally protect the remains through the process of scheduling. In that event the developer would need to seek separate scheduled monument consent before continuing work. It is also open to the local planning authority (or the Secretary of State) to revoke planning permission if necessary. In this case the developer may be liable for compensation. In the majority of cases, however, it should prove possible for the parties to resolve their differences through voluntary discussion and for a satisfactory compromise to be reached.

Dissemination

Introduction

While most historic environment work considered in this manual is development-led the results of such work may be of value to a wider audience than the parties professionally involved. To achieve this, results of historic environment work must enter the public domain as part of the planning condition.

Background

Historic environment professionals (contracting archaeologists) should bear in mind that there is a requirement to report the findings of a historic environment project beyond the normal planning audience. This may range from the publicising of a small project amongst the local public to mass media publicity for finds of national interest.

The report

Lincolnshire Historic Environment Record

Each county or unitary authority in England has a Historic Environment Record (HER or Sites and Monuments Record (SMR). The Lincolnshire HER is held and maintained by our Historic Places Team (see Appendix 7 for the address). The information held within the HER forms the basis for the appraisal of historic environment needs within the planning process by both county and district historic environment staff. It is essential that the database is continually updated to ensure adequate historic environment management responses to development issues. The HER is a public resource and is available for consultation to all those with an interest in studying the past or managing the heritage. Copies of all reports, interim and final, should be lodged with the county HER. The needs of commercial confidentiality may apply at a pre-application stage and can be accommodated but should be arranged at the time of deposition. Reports that are deposited as confidential will normally be released into the public domain after six months. All reports produced to support a formal planning application or are used to discharge a planning condition will be in the public domain.

Local Archaeological Journal

The journal Lincolnshire History and Archaeology is the main organ for the publishing of the results of historic and archaeological work in Lincolnshire.

OASIS

The OASIS project (On-line Access to the Index of Archaeological Investigations) brings together a number of strategic partners, including: the Archaeology Data Service and Historic England under the umbrella of the University of York.
The planning archaeologists in Lincolnshire have, as a group, made a decision to adopt OASIS and ask for OASIS forms to be completed as part of the planning process. The requirement to complete OASIS forms on-line should be included in all briefs and acknowledged in all specifications in Lincolnshire.
The contractor should provide a copy of the completed project summary page from the OASIS record. This should either be bound into the grey literature report as an appendix or attached to any covering letter that is sent to the planning archaeologist.
The overall aim of the OASIS project is to provide an online index to the mass of archaeological grey literature that has been produced as a result of the advent of large-scale developer-funded fieldwork. The OASIS data capture form has been designed to help in the flow of information from data producers, such as contracting units, through to local and national data managers, such as SMRs, HERs and the NMR. In Lincolnshire the resulting information will be validated by the planning archaeologists and/or the relevant records officers at Lincoln City Heritage Database, North Lincolnshire HER, North-East Lincolnshire HER, the Lincolnshire HER and the Heritage Trust of Lincolnshire, and passed onto the ADS for inclusion in its online catalogue ArchSearch. A unique OASIS record should be created and completed for each separate report or phase of archaeological work. Digital copies of the project report should, wherever possible, be attached to their associated OASIS record, so that they can be added to the Archaeology Data Service's online Grey Literature Library, for wider public dissemination.
Since the completion of an OASIS form will effectively place a synopsis of the results of archaeological work in the public domain, the Lincolnshire planning archaeologists will no longer require contractors to report the findings of an archaeological project in the local archaeological journal as a brief listing, or as a longer note, on a piece of fieldwork. However, it is expected that full reports of large-scale fieldwork will still be needed, such as those that appear in Lincolnshire History and Archaeology and in national journals from time to time.

Geoarchaeological assessment

Geoarchaeological assessment is recommended as a standard component of development-led archaeological investigation within Lincolnshire, particularly where proposed works may affect alluvial, colluvial, coastal, or other sedimentary deposits. Such deposits often preserve important paleoenvironmental sequences that inform on past landscapes, land use and human activity and may help with understanding site formation, potential and deposit modelling.

Geological and geoarchaeological context: The Fenlands, The Wash and River Valleys

Lincolnshire contains extensive superficial deposits of alluvial silts, marine clays, blown sands and peat sequences. These are particularly developed in the Fenland basin and coastal margins, where long-term marine, fluvial and aeolian processes have created thick, complex sedimentary sequences. Archaeological remains can often be found within or buried beneath these deposits, sometimes at considerable depths, and the ability to recognise these requires appropriate geoarchaeological techniques. Depending on the scale of development and complexity of the geological context it may be necessary for a geoarchaeologist to provide input.

The Fenlands and The Wash are characterised by a distinctive Holocene sequence of clays, silts, peats and paleochannels. Subtle elevation changes created localised “islands” or roddon crests that were attractive for past human settlement, while extensive tidal silts and marine alluvium often mask underlying archaeology.

The Terrington Beds (tidal-flat deposits) dominate the northern Fens.
Earlier deposits of Upper and Lower Peat and Fen Clay remain buried at depth, preserving paleoenvironmental archives of high research potential.
Roddon crests (silted paleochannels) are a recurrent geomorphological feature; they can be detected by aerial photography, LiDAR or geophysics and may contain both archaeological material and paleoenvironmental remains sealed within former channel fills. Understanding this sequence is fundamental to evaluating archaeological potential and to developing proportionate mitigation strategies in fenland and coastal settings. Where LiDAR, geophysics, aerial pictures or terrain models identify roddon crests, it is important to assess their depth and internal composition. Former channel fills may contain well-preserved paleoenvironmental remains and waterlogged deposits within later freshwater channels of archaeological significance.

Why it matters

Understanding landscape context

Many archaeological sites in Lincolnshire are preserved within or beneath superficial deposits (for example, river valleys, fenland, estuarine margins). Geoarchaeological assessment provides evidence of past topography, hydrology and landscape change.

Particular relevance in The Fens

This landscape is characterised by complex sedimentary processes and subtle elevation changes. Archaeological remains are often located on slightly raised ground or “islands,” but can also be sealed beneath marine silts, alluvium or blown sands. Without geoarchaeological assessment, this masked archaeology may be overlooked.

Dating and phasing

Sediment cores and stratigraphic analysis allow correlation with regional sequences and provide opportunities for absolute dating (for example, radiocarbon, OSL). This contextualises archaeology within a reliable chronological framework.

Assessing preservation potential

Paleoenvironmental remains such as pollen, molluscs, diatoms and macrofossils are often preserved in waterlogged contexts. Targeted geoarchaeological investigations can facilitate the systematic recovery of such material, enabling structured evaluation of their survival and preservation.

Informing evaluation

Early engagement with geoarchaeological approaches can help shape subsequent evaluation strategies. For example, a desk-based geoarchaeological assessment may identify ground conditions that limit the effectiveness of certain geophysical survey techniques.

Informing mitigation

Results guide decisions on appropriate mitigation strategies (preservation in situ, sampling, targeted excavation), ensuring proportionate responses aligned with planning requirements and research frameworks.

When to recommend

Geoarchaeological assessment should be considered whenever it will substantively inform the pre-determination evaluation process:

development affects:
- floodplains
- valley bottoms
- former wetlands
- peat deposits
- complex and, or deep deposits in urban contexts
- estuarine and foreshore environments
there is potential for deeply stratified sequences containing or masking archaeology
previous investigations indicate paleoenvironmental survival or significant sediment accumulation

For large-scale or complex schemes, geoarchaeological assessment should be considered as part of the evaluation strategy, particularly where it can inform deposit modelling and landscape reconstruction. It can complement standard techniques by improving understanding of stratigraphy, site formation processes, and preservation conditions. This is especially important where deeper deposits may be present that standard approaches, such as magnetometry surveys, are less effective at characterising.

Methodological expectations

We currently accept several approaches and strategies for geoarchaeological assessment. Any chosen method should be tailored to the development proposal impacts and ideally be informed by the results of the geophysical survey and developed in consultation with a suitably experienced geoarchaeologist and the LPA planning archaeologist.

Method selection relative to likely impact

Approaches should be proportionate to the anticipated depth of impact, the complexity of the sequence, and the level of uncertainty.

The following case studies provide examples of how different methodological considerations were applied in two different impact scenarios.

Accepted strategies include:

Geoarchaeological desk-based assessment (GDBA)

The use of existing geotechnical data, including historic borehole or geotechnical records, any developer-commissioned ground investigations, and data from adjacent areas to model site conditions without further intrusive work. Depending on the nature and scale of the project this may be presented as a section of a standard desk-based assessment, or a standalone document.

Boreholes and drilling transects

Commercial rig, power auger or hand auger. Undertaken when the deposits of interest are too deep for shallower methods, or when large areas need to be covered. Core extraction geoarchaeological borehole records are required to enhance understanding of site stratigraphy and to assess paleoenvironmental potential. Boreholes are used to clarify the nature and depth of subsurface deposits, to locate and date former land surfaces, roddons, alluvial and peat layers, and to evaluate their archaeological potential. The method also allows the identification of natural and anthropogenic changes to the landscape, both wetland and dryland, including activity associated with valley use or historic crossing points.

Geoarchaeological test pits (rapid sondages)

On sites where the sequence of interest is shallow it can be more effective to use test pits. Depending on the nature of the research question, geoarchaeological test pits (rapid sondages) may be excavated with an appropriate, fit-for-purpose mechanical excavator. In such a scenario the work proceeds in controlled spits of approximately 50mm to the safe reach of the machine arm, with depth reduced where groundwater, flooding or instability occur. Sedimentary units are recorded in sequence, noting grain-size, consolidation, colour, structures and materials.

Drawing can be done from a distance or sketched and there is no need to enter a deep rapid test pit. The drawing should be sufficient to understand the stratigraphic sequence and depths of deposits. The method is designed primarily to investigate and model Fenland deposits while also assessing the potential for deeply buried archaeology. Where archaeological features are identified in overlying deposits, these may be recorded (in agreement with the LPA planning archaeologist and client) or the sondage relocated to avoid disturbance, and modern intrusions truncating the deposits may be removed where practicable.

Combined approaches

In most cases a staged, iterative approach should be adopted, starting with a GDBA, deposit modelling, and targeted field investigation (for example, test pits or boreholes) where necessary. Techniques should be selected and applied in a proportionate, question-led manner to refine understanding of deposit sequence, extent, and preservation. The phasing of work will be determined by the nature of the project Early-stage fieldwork may be required in some cases, for example to inform the selection of geophysical techniques or to be carried out in parallel with geotechnical site investigations. Alternatively, test pits, sondages and/or boreholes may be undertaken simultaneously with archaeological evaluation, within or adjacent to trenches, depending on project design. Geoarchaeological engagement with the project may need to continue through mitigation phases.

Specialist advice and site attendance

Samples

Following the outline strategy presented in the Written Scheme of Investigation and in consultation with a geoarchaeologist, samples will be collected for:

scientific dating
analysis of chemistry
magnetic susceptibility
particle size
micromorphology
other techniques as appropriate

Special consideration should be given to any evidence for recent changes in preservation conditions that may have been caused by alterations in the site environment.

Geoarchaeology studies should follow the guidance provided by Historic England (2015, 2020). Consultation with an environmental archaeologist or the Historic England Regional Science Advisor may be required. This incudes site visits to refine sampling strategies and advise on palaeosos or deposits of high environmental potential.

In some cases, the presence of a geoarchaeologist on site during evaluation or sampling will be required to provide real-time advice.

Health and safety and ecological constrains

Particularly in the case of geoarchaeological test pits and rapid sondages, it is paramount to abide by all relevant and current health and safety requirements. Risk assessment and compliance with site-specific health and safety procedures must be built into the project design and fieldwork strategy. Other considerations and potential risks from open deep excavations on local wildlife should be considered.

Historic England guidance and further reading

Please contact us by email at Archaeology@lincolnshire.gov.uk for details on the above.

Version history

This guidance was authored by Ruben Lopez Catalan, Historic Environment Officer at Lincolnshire County Council with input from:

Matt Nicholas, Science Advisor for the East Midlands
Matt Canti, Senior Geoarchaeologist based at Fort Cumberland
Hayley McParland, Science Advisor for the South West
Nick Carter, Inspector of Ancient Monuments covering Derbyshire and Staffordshire, Historic England

June 2026

Guidance for large schemes

Cultural Heritage should be ‘scoped in’ and appropriate assessments included as part of the Environmental Statement. The Infrastructure Planning (Environmental Impact Assessment) Regulations 2017 states "The EIA must identify, describe and assess in an appropriate manner…the direct and indirect significant impacts of the proposed development on…material assets, cultural heritage and the landscape." (Regulation 5 (2d)).

Potential for impact on archaeology

Developmental impact for solar farms includes tens of thousands of piles, cable trenching, associated infrastructure and mitigation measures such as scrapes and wildlife ponds, all of which could disturb and destroy surviving archaeology. There is potential for compaction during construction and decommissioning while through the lifetime of the scheme there will be refits which involve ripping out the old infrastructure and putting in new. In archaeological terms we as a profession are coming to realise that solar schemes are at least as damaging to archaeology as housing developments.

Full impact zone

The full extent of the proposed development area, including the connector route corridors, will need to undertake sufficient evaluation to allow for a programme of suitable mitigation. Archaeological impacts and subsequent mitigation have the potential for significant financial and scheduling impacts. Sufficient evaluation is therefore essential in informing the selection process and in ensuring the subsequent design and work programme is devised with an understanding of the level of archaeological work which may be required before and during the construction phase.

Search requirements

Archaeological evaluation will be undertaken as part of the assessment process, details and intended scheduling should be provided at the earliest opportunity and more specific information will be required going forward.

HER data for a 2 kilometre radius is required from the redline boundary and including any proposed options. Until they are descoped all cable route options need to be properly assessed as part of the development and as part of the Environmental Statement (ES).

All designated assets (for example, Scheduled Monuments and Listed Buildings) within a 5 kilometre radius should be taken into account for setting assessments. The significance of each asset must be assessed prior to scoping which assets would be affected. Modelling should particularly include any identified assets which have the potential to be visible or have their setting affected by the taller elements of the development.

Requirements for sufficient evaluation

It’s vital that a competent full desk based assessment (DBA) be completed at the earliest opportunity as desk based work provides the basis for initial understanding. This is informed by and built upon by a full air photo, LiDAR assessment and geophysical survey which in turn assists in the development of the trial trenching programme. The results of all the evaluation phases are required to form the baseline evidence and allow for sufficient understanding of the archaeological potential across the scheme. The evaluation work must be completed in time to inform the mitigation strategy which will lay out how the developmental impact on archaeology will be dealt with, therefore this will need to be submitted as part of the EIA.

Desk based assessment (DBA)

A desk based assessment must be submitted prior to the trenching WSI as it is required to inform an effective evaluation strategy. The DBA should include all reasonably available desk based information for the full extent of all proposed impact areas including any cable or connector routes.

Desk based sources should include full LiDAR and air photo coverage and assessment (details below); archaeological reports; Portable Antiquities Scheme (PAS) data and local sources and archives.

Map regression should include all available maps to provide a reasonable understanding of the development and time depth of the sites.

LiDAR and air photo assessment

A full competent LiDAR and air photo analysis, interpretation and assessment is required with full aerial photo coverage using all available oblique and vertical air photos including the Historic England Archive and Cambridge University Collection of Air Photos as well as RAF and Ordnance Survey photos including those held by Lincolnshire County Council.

Geophysical survey

A geophysical survey must be undertaken of the main development site and all potential cable connector routes until they have been selected or descoped.

The results are required to identify site-specific archaeological potential and to inform a programme of archaeological trial trenching and subsequent mitigation. Pre-determination evaluation of the cable connection corridors can be very useful with informing a decision on the most cost effective and viable route.

Regarding the geophysical survey a single Written Scheme of Investigation should be prepared that all contractors adhere to. This must include appropriate quality and control measures to ensure consistency of data recovery across the site.

In the event of multiple contractors separate reports for each contractor should be supplied in full and the consultant will supply a comprehensive and robust overarching report presenting the combined results as this will inform the subsequent evaluation trenching.

Trial trenching

Trial trenching is required as trenching results are essential for effective risk management, project management, programme scheduling and budget management. Failing to do so could lead to unnecessary destruction of heritage assets, potential programme delays and excessive cost increases that could otherwise be avoided.

Curators across the country are on a steep learning curve regarding the extent of the impact across these schemes as the specific impacts across the redline boundary are not included in the submission documents. It’s clear to us now that 1% or 2% trenching isn’t sufficient to undertake an adequate assessment and this has informed the emerging regional guidance requiring 3 – 5% trenching while understanding that this percentage will mean that significant archaeology is lost.

As well as targeting known and potential archaeology the trenching strategy will need to target those areas where earlier evaluation phases have not been successful in locating archaeology. Targeting blank areas is an essential part of determining the archaeological potential across a proposed development as different types of archaeology and geology may limit or mask the effectiveness of non-intrusive evaluation techniques.

Sufficient trenching will be required across the full impact zone to determine the presence, absence, significance, the depth and extent of any archaeological remains which could be impacted by the development.

The results of trial trenching will inform a robust mitigation strategy which will need to be agreed by the time the Environmental Statement is produced and submitted with the Development Consent Order (DCO) application.

Settings assessment

Regarding a competent settings assessment, the application site may affect the setting of several scheduled monuments as well as a large number of designated and non-designated heritage assets. The settings assessment or heritage impact assessment needs to begin from an understanding of the significance of each of those assets in order to assess the potential impact of the development on them and put forward any potential benefit or mitigation of proposed negative impact.

Environmental impact assessment (EIA)

The EIA will require the full suite of comprehensive desk-based research, non-intrusive surveys, and intrusive field evaluation for the full extent of proposed impact. The results should be used to minimise the impact on the historic environment through informing the project design and an appropriate programme of archaeological mitigation. The provision of sufficient baseline information to identify and assess the impact on known and potential heritage assets is required by Infrastructure Planning (Environmental Impact Assessment) Regulations 2017 (Regulation 5 (2d)), National Planning Statement Policy EN1 (Section 5.8), and the National Planning Policy Framework.

Sufficient information on the archaeological potential must include evidential information on the depth, extent and significance of the archaeological deposits which will be impacted by the development. The results will inform a fit for purpose mitigation strategy which will identify what measures are to be taken to minimise or adequately record the impact of the proposal on archaeological remains which must be submitted with the EIA.

This is in accordance with The Infrastructure Planning (Environmental Impact Assessment) Regulations 2017 which states "The EIA must identify, describe and assess in an appropriate manner…the direct and indirect significant impacts of the proposed development on…material assets, cultural heritage and the landscape." (Regulation 5 (2d)).

Please note that the Historic England Regional Science Advisor should be consulted on the project as well as providing advice on geoarchaeological assessment.