Tag Archives: archaeology

Geophysics at Allen Archaeology

Archaeological excavation is by its very nature a destructive activity. In order to properly understand and record the archaeology it may necessary to actually remove any physical traces of the archaeology leaving behind only written records, drawn plans and photographs. Commercial archaeology is in a lot of cases an attempt to rescue or record archaeology before it’s destroyed by future building work. Part of the problem is that while historic records can often give an idea of what might be found within a development area, the actual nature of potential archaeological remains actually require some intrusive investigation…… or do they?

This is where the science (or some might argue the art) of geophysical surveying can allow a non-intrusive view into the past. If the location of archaeological remains can be identified without sticking random holes in the ground it can allow a much more targeted, and potentially less destructive, approach to be taken. This can also save a lot of time and money within the construction process. A geophysical survey can also allow the bigger picture of a site to be revealed.

Undertaking a magentometry survey

There are a number of different geophysical techniques used within the archaeological world, unfortunately none are perfect for all conditions and locations. There are a few main techniques that are widely used

• Resistivity. Resistivity involves an electrical current being fed into the ground and the resistance to this current being recorded. The usual approach being a two pronged machine placed into the ground at regular intervals across the required area with readings taken at each location. High resistance readings may suggest walls or rubble fills, whilst low resistance readings can indicate ditches or drains.
• GPR (Ground Penetrating Radar). GPR uses radio pulses transmitted vertically downwards and the reflection of these pulses from buried layers and structures to build up a picture of ground below. GPR has the ability to provide a three-dimensional view of a buried site.
• Magnetometry. Magnetometry relies on the ability of the magnetometer to measure very small magnetic fields associated with archaeological remains. These magnetic fields are either the result of thermoremanence or magnetic susceptibility. Thermorenanence occurs when weakly magnetic material is heated up and then cools. The material can then gain a permanent magnetisation associated with the direction of the earth’s magnetic field while it cools. The magnetic susceptibility of a material is related to the magnetism induced when the material is placed within a magnetic field. Since the earth’s magnetic field is always present, the magnetic susceptibility of buried material can be measured using the magnetometer.

There are other geophysical techniques used in the search for buried archaeology, seismic, microgravity, induced polarisation and metal detecting to name a few. However the three main techniques are resistivity, GPR and magnetometry.

Results of a survey showing a potential medieval settlement in Leicestershire

Within commercial archaeology the most widely used method is magnetometry. This is mainly due to the speed at which large areas can be covered and the impressive results that can be obtained. As with all methods however the site conditions will dictate how suitable the technique is. Within built-up urban locations magnetometry will be next to useless due to the interference of external magnetic fields from buildings, cars, modern services or modern rubbish. All these and more can mask the small magnetic fields generated by buried archaeology. In this situation GPR may well be a far better choice.
I’ve now been working for Allen Archaeology for 5 and half years and whilst these days I am allowed out to occasionally dig, my main duties are as a Geophysical Project Officer. This involves both the physical part- actual surveying, and the office based part- processing data and writing reports. I look upon the latter as a necessary evil which allows me to spend time on the much more enjoyable (mostly) former. Fortunately the majority of the sites we survey are not completely waterlogged, and despite the reputation the British weather has for rain, I do seem to manage to stay fairly dry. Except for my feet when I don’t realise my (non-metallic) boots have holes in them.

Iron Age/ Roman settlement in Nottingham

Geophysical surveying large sites can be very hard work. There is a lot of walking involved, both in setting out grids and in actually surveying. My legs and feet have suffered somewhat over the last few years; blisters are a not uncommon occurrence. However as an aid to fitness nothing beats walking 20-25km a day across fields. The exciting part is of course when I get to see the downloaded data for the first time. On many occasions there can be a little disappointment as all that is revealed is a former field boundary or in some cases nothing of interest at all. However every so often something far more exciting is revealed. I get to be the first person to see Romano-British field systems, forgotten medieval settlements, ploughed out ridge and furrow cultivation, or even outstanding modern drainage systems.

The practical side of the geophysical survey is that it can be done fairly swiftly, covering 2-3 hectares a day (all depending on site conditions of course). Then specific areas can be targeted for excavation if necessary. This can potentially allow a ‘key-hole surgery’ approach to the archaeological remains, limiting the destruction whilst maximising the information gathered through digging. Plus it can be very satisfying when an excavation reveals my geophysics results to be completely accurate.

Training in smaller companies – how and why we do it

Formal training is perhaps seen as the preserve of the larger, more established archaeological unit able to put considerable resources into training schemes and have staff specifically dedicated to implementing them. However, working for a smaller company can provide better opportunities for consistent mentoring and for a diverse training experience.

On Wednesday 20th April, AAL contributed to a session organised by the Diggers Forum at the Chartered Institute for Archaeologists (CIfA) annual conference, entitled ‘The skills gap: training for competence in archaeology’.

AAL has undergone pretty rapid growth. In January 2014 there were 14 staff and by the end of last year we had 45 staff, including three trainees. Training plans are put in place for staff to progress and to change direction, for example into geophysics or archives, but this post focuses on our ‘entrance level’ training plan.

So why is training important? Well, with increasing workload and larger jobs we needed more people; not only did we need to increase capacity but also flexibility. Training gives us the chance to grow skills in-house which are tailored to company methods and needs. Like many archaeological companies out there we had recruitment problems – especially for fixed term roles. The problem wasn’t numbers of applicants but that very few had the experience we were after. Partly it was about need, and partly about gaining the confidence to do it. We’re involved in community archaeology projects, site open days, National Trust training days and short-term university teaching, so surely we ought to have the skills in-house to train other archaeologists? Most of all, training the next generation is, as one of our recent trainees put it, a good thing to do!

“A lot of companies want minimum experience that might be hard to get even with volunteer work and the like, so obviously a scheme that trains less experienced archaeologists is a good thing.”

It was important to us that we weren’t playing lip service to training as a way of paying people less, so we decided to keep the training plan short and sweet – 3 months should be enough to get a good grounding in commercial archaeology and to get people with some pre-exiting skills and experience to PCIfA level (Practitioner – the first level of competence defined by CIfA).

The training programme is aimed at people who have genuine interest and aptitude but no commercial experience, though we have found that applicants sometimes do have this, just not the amount most commercial jobs require, so they couldn’t get started on the job ladder. We wanted a way to get people on to that ladder and to keep them moving up through the company, gaining experience and moving to permanent roles over time.

Josh training the team in flint identification

The company ethos is very much that everyone should learn the basics of everything and that knowledge and skills are shared. We’re not heavily departmentalised so staff get to carry out GPS and TST survey, use GIS to produce illustrations for reports, assist with geophysical survey, take their own site photographs and so on – it is possible that this might go as we grow further, but we will try and hold on to this as much as is possible.

Trainees get a formal plan with tasks to sign off and each task has an appointed person to do the sign off. Over three months. The standard plan involves 20 days of fieldwork, 10 days in the finds and archives, eight days post-excavation work and five days survey training, plus time for an induction, basic introduction to standards, H&S and so on. The tasks are tied to National Occupational Standards.

It is not without its problems. The level of training dependant on and workload – one of our recent trainees didn’t dig on a ‘normal’ site for three months as we were working on the sampling of a the top of a paleosol for Mesolithic flints, and this meant that she hadn’t experienced stratigraphic recording. It’s vital to keep balance on site so there are enough experienced staff to support the trainees, and because we’re relatively small, the training experience is also dependent on the availability of particular staff. Good training also relies on good feedback from site supervisors – building on feedback from previous trainees, new posts will include a formal monthly meeting with an appointed mentor…but fieldwork programmes can make implementation of this tricky. Importantly all those involved need to understand the purpose of a training plan. It mustn’t become a race to complete sign off of tasks but be paced to enable time and a genuine understanding to develop.

Trainees work in the field for around 20 days in three months

Giving staff the chance to build on and share their experiences is vital (even if it is potentially a little scary for the management team) and our AAL Xmas lectures, where staff give presentations on aspects of their work throughout the year, are just one way in which we do this.

“You only need to look within the company to see that it’s working with a number of former trainees now in other roles.”

So is it working? Well, since January 2014 AAL have taken on 10 trainees (that isn’t including people like Feenagh who had started before this but were/are still progressing on training plans). Two of those trainees started with the company as short-term volunteers. Six were offered contracts as Project Archaeologist (PA) at the end of their training plans: two have now specialised in non-field areas within the company (archives and DBA), two are currently field PAs, and one left for a non-field promotion outside the company and one has taken a break from archaeology. One trainee could not be given a PA contract due to a downturn in work. Only one traineeship didn’t work out.

“There was a balanced mix of office-based and site-based work that allowed me to develop excavation skills on small-large scale excavations, whilst learning how to make the transition from site material to post-excavation reporting smoother for all involved. All in all, my experience was really quite rounded. I enjoyed it immensely and it gave me the skills to feel confident to work at any site, or in the office”

“I’m very grateful the trainee scheme exists as it allowed me to get into commercial archaeology when it might have otherwise been difficult”

“It gave me a proper view of what commercial archaeology really was and I didn’t feel like my lack of experience prevented me from going on any site or prevented any opportunities … The staff at Allen are all very friendly and helpful which made asking questions, help and generally becoming a part of the team so much easier.”

“I found my trainee programme very beneficial as I previously had no experience digging – either commercial or academic, so was a great opportunity to get into archaeology and be paid for it.”

The numbers we can take on are small – we’re not going to solve the skills shortage single handedly – and I’m not trying to claim we’re perfect, but with a little thought, it is possible for even small companies to create effective, useful and robust training programmes that benefit the trainee and the company in equal measure. The interest we have seen as a relatively new and less well-known company, with applications from across the UK and Europe, is pretty staggering and suggests that we need to find a much better way of serving the next generation.

We’re looking forward to welcoming our latest batch of trainees at the start of May and to building on and improving our training going forwards.

Training at Allen Archaeology Limited

According to a helpful little counter that shows up on my employment record I have been working for Allen Archaeology for 2 years 6 month and 23 days. Nothing particularly ground breaking, but in that period of time I been fortunate enough to work on some incredibly interesting and exciting sites but I’ve also progressed from a Trainee Project Archaeologist to Project Supervisor level and in the process received a staggering amount of training and learned what it means to be a commercial archaeologist along the way.

Taking part in a field school at Nevern Castle while at uni

I have always loved history, but it wasn’t until I started looking at University courses that I realised that when I grew up (!) I actually wanted to be an archaeologist! So in 2010 I went to study Anthropology and Archaeology at Durham University, partly because it was something that I thought would be interesting and partly because they let me live in the castle. It was pretty good in that it gave a very comprehensive overview of archaeology, but like most archaeology degrees lacked in practical aspects; in fact there were no compulsory archaeological fieldwork modules as part of the course. Nonetheless, I left Durham with 8 weeks of field experience, and the overwhelming impression that commercial archaeology may not be something I really wanted to look into; it was a bit too cynical and our yearly “careers” talk made it seem like the commercial world was not an exciting one to work in. So when my degree ended I made the decision to take a year off, earn some money, and then go back and do a masters.

This plan however spectacularly failed. I moved back to Lincolnshire and got a call from AAL (a year after I had applied to be a volunteer with them!) asking if I was available to work and offering to employ me. I started in September 2013 as one of their trainee site assistants, with very little experience of what commercial archaeology was or what was expected of me.

I did have a trowel though; so it was a start.

Where I cut my teeth was at AAL’s colossal North Killingholme project (NKAM) and training was given on the job. I was told what I was expected to do and then left to get on with it; sort of like being thrown in at the deep end and “shadowing” the other project archaeologists when I needed guidance. There was no formal training plan but I think it was a pretty effective way of learning the basics, and there was always someone nearby to help when I got lost.

It was fairly simple archaeology to begin with, putting metre sections through Roman ditches, and the thing I remember most is continuously being squeaked at and asked by the PO on site “Are you happy with those edges?”. It turned into a bit of a game with all the other PA’s on site, lightly mocking this phrase, but it taught me how to excavate quickly and accurately and helped me progress into being a real Project Archaeologist. Learning how to record took me a little longer however, it was a whole new experience being shown how to draw to scale and how to trust my interpretations of features, but I got there eventually and was able to move onto digging larger and more exciting features, like ditch intersections, Roman Kilns, and ring ditches.

Excavating a skeleton in October 2014

That’s one of the things I enjoy about working here, that there is a lot of effort devoted to trying to training staff and to give everyone a rounded knowledge base; everyone learns how to work the survey equipment and is expected to be able to excavate and record a feature from start to finish, and everyone gets some experience in post-ex be it finds processing, writing context summaries, or producing figures. It’s something that I massively benefited from.

The next year was a massive learning curve and I received a lot of training beyond the practical skills I was still learning in the field. I got to handle a lot of the material remains that were coming from sites through washing and processing the finds and I started learning the basics of post-excavation work and about working with GIS programs by digitizing drawings and phasing sites. I spent a lot of time staring in frustration at muddy scans while digitizing plans and sections and at the array of pastel colours used to phase the NKAM sites, . It wasn’t always the most exciting things, but it defiantly helped me become a more rounded archaeologist, and made me realise the importance of properly recording and checking the work we do on site!

DIgging the ring ditch at North Killingholme

At the end of June 2015 positions became available within the company for Project Supervisors and, with the support of my line manager, I applied and was given the job as a trainee supervisor. Unlike my last traineeship, this position had a much more structured training plan and I was given tasks which needed to be signed off by various managers and project officers in order to check my progress. It was a little messy at first as there was still a massive hands on approach, and it took some time to actually be able to put the training plan in place for various reasons, but I started off in a safe place, back at Killingholme guiding our new trainees, before being sent off on some of my own jobs. Like before I started off small; with small scale watching briefs and evaluation sites which over the next few months gradually progressed into slightly larger jobs, with a few other team members to supervise. It took some adjusting to (and a lot of site visits and phone calls asking questions before I got my bearings!), but it was exciting and I got to work on some interesting sites and developed a particular interest in community based archaeology. I had enjoyed working on some of the previous outreach projects such as the open days at North Killingholme and at the Canwick Bomber Command Memorial site in 2014, so when I was given the opportunity to work on a few community projects run with the National Trust I jumped at the chance!

Talking to volunteers on a community dig at Hinton Ampner

What changed most with this new role, however, was the responsibilities beyond the fieldwork and learning how to manage a site, and I got the chance to develop more post excavation skills. I learned how to structure reports and produce figures and I spent a lot of time in the office repeating this process until it was second nature. Again it’s not always the most exciting thing, and some days it’s incredibly frustrating and I wish I was outside happily digging ditches, but it is worth it. There is a special sort of pleasure you can take in making a figure look pretty, or getting your teeth stuck into a particularly interesting site you are writing up!

I suppose what I take from all this reminiscing about the considerable range of traineeships and professional development I have experienced within Allen Archaeology over the past two and a half years, is that I’m incredibly proud of my achievements here and, despite a number of stumbles along the way, I am very grateful for the continuous support and guidance I have received at all stages, from everyone within the company. It’s made me the archaeologist I am today and I love my job, especially the community projects and the opportunities to be involved in new team members training, and I hope I give them even a little but as much encouragement and support as I received when I first started.

But I’m still learning.

And I may have realised that now I’m not always joking when I ask people on a site I am supervising if they’re happy with their edges….

Digital Techniques: Structure from Motion (SfM) Photogrammetry

Warning: Images of human remains feature in this post

If you’re involved in the heritage sector then chances are you’ve seen a three dimensional (3D) model of an archaeological site, feature or artefact that you can view and interact with on a computer screen or mobile device. It’s likely this was created using SfM, which operates under the basic principle that 3D structure can be resolved using overlapping images. Photogrammetry is the science of making measurements from photographs. Therefore, SfM photogrammetry is the use of photographs to accurately record 3D models from which measurements and details can be recorded. I could go into more detail regarding the technique itself works but for now lets just assume it’s tantamount to magic!

Capturing a collard urn

We’ve been exploring the possible uses here at AAL for a couple of years now after initially learning about its potential from the master of archaeological photography, Adam Stanford (http://www.aerial-cam.co.uk/). Initially we trialled the technique out in the field for the recording of skeletons and masonry because these are two often poorly recorded feature-types; that and our office at the time was somewhat unsuitable for artefact recording (to put it mildly) and my spare bedroom/dark room at home was full of kittens. What we found was that, if recorded properly on site, the technique allowed for a more accurate record of the feature from which a traditional illustration could be made and disseminated to specialists to aid in their assessment/analysis.

Example of a record using SfM on site

It also allowed us to revisit these features from the comfort of the office (the new one, not the old one) and examine them in closer detail than we had time for on site.

Masonry recording

By the time my fieldwork marathon was complete we had a new head office in Lincoln with plenty of space for us to experiment with SfM on artefacts. Trial and error was key here, and there were many failed attempts before finally working out a methodology fit for the task (credit must go to Hugh Fiske for providing the inspiration needed to complete this and I’m sure you’ll agree he’s made some beautiful models, http://www.archaeo3d.me.uk/)

Part of the company ethos here focusses on training for all, and as soon as we were happy with the workflow we began training others in this recoding technique. Currently we’re building up a portfolio of models so that in the near-future we can showcase them online for everyone to access, so watch this space.

Chris training Andrea and Charlotte in Structure from Motion

A postcard from Oslo

At the end of the March I spent four days at the University of Oslo for the Computer Applications and Quantitative Methods in Archaeology (CAA) annual conference. AAL were fantastic and supported my attendance, as did a low income bursary from CAA International. Last summer, prior to getting a job with AAL, I agreed to run a session with Stuart Eve of LP Archaeology at the conference focussing on digital approaches to multisensory engagements with the past (Interpretations from digital sensations). We decided to run the session on the back of a series of discussions we have both had on twitter about each of our research trying to move beyond a visual interpretation of the past.

Piotr Dziewanowski from the National Maritime Museum in Gdańsk presenting scans of the Soldek

Lawrence Shaw’s 3D printed Digital Elevation Model

I presented a paper in the session and we had two other speakers; Lawrence Shaw of the New Forest National Park and Piotr Dziewanowski from the National Maritime Museum in Gdańsk. My paper seemed to go down fairly well, which is always nice, and the other two papers were fantastic. The team from Gdańsk presented a series of scans of the museum ship the Soldek, which looked like an incredibly complicated project and produced some amazing outputs. While Lawrence Shaw and his team demonstrated the use of 3d printing to engage the public with the Lidar; letting people “get tactile” with the landscape.

While I was out there I also had some great conversations about how to introduce more digital techniques or applications into commercial archaeology, a slightly ignored subject, and “enthusiastically” discussed over a few glasses of wine at the fantastic Museum of Cultural History… The underlying theme of those discussions was not that commercial archaeology did not need to introduce new and shiny methodologies and applications, but rather that there was no time in the commercial world to roll out and field test new on site approaches and in the UK archives are frequently not willing to accept digital data. For example, I saw numerous approaches to using tablets onsite for recording, instead of the traditional context sheets. This would allow us to avoid digitizing these at the end of the project and should in theory force the appropriate data to be collected in the field. However, setting up and ensuring this system works on the software end would require a lot of development. There are costs associated with buying in the kit. And also is the hardware capable of dealing with a British winter… (Though Mike and Flo from LP highlighted that you can buy ruggedized tablets; the issue is ensuring they are cleaned and dried on return from the field).

One of the Viking Ships and the incredible building they are housed in

Detail of the woodworking from one of the ships

Somewhere along the line we went to visit the Viking Ship Museum, where my inner maritime archaeologist got very excited. The boats, the artefacts, the preservation, and the building they are presented in is amazing!

One of the sessions that really stood out for me was run by Gary Lock, Agiatis Benardou, Costis Dallas, Paul Reilly and Jeremy Huggett; a roundtable on scenarios for the next five years of archaeological computing. It was a really challenging session making us all think about the future of digital archaeology and I’m looking forward to hearing about the follow up to the session.

Finally on the last day I “conference-bombed” the digiTAG session ran by my friend Sara and her colleagues. They had a couple of presenters drop out and wanted to fill a couple of spots. All I can say what seemed like a good idea at 10pm after a few pints seemed less appealing at 6am the next morning. But I gave a quick presentation on theorising archaeo-acoustics, a presentation I had wimped out of submitting to their session in the first place; and I think it was well received (or at least twitter seemed to think so). The whole session was fantastic and drew together a number of my thoughts on the lack of theoretical engagement with digital approaches. I was sad to miss the concluding discussions.

Best site hut biscuit with Pickle

Site visit selfie #safteyfirst

What is your job role?
Office dog

How long have you worked for Allen Archaeology?
Nearly 6 months

How would describe your excavation technique?
Fast! But possibly in need of direction

How long have you been working in archaeology?
Nearly 6 months

How did you get into archaeology?
One member of my household staff had to go away for a week so the other had to bring me to the office. Everyone was so nice I couldn’t possibly consider doing anything else.

What is the best thing about your job?
Engaging with people, when I’m in the office everyone wants to talk to me and see what i’m “working” on!

Working hard in the office

Specialist skills?
Claiming sites – if you want that piece of masonry or mud marked, I’m your dog!

Best site hut biscuit?
Any within nose height!

Best site hut biscuit with Jedlee

Jedlee Chapman Welcome to the first post in a series where we meet some of the AAL staff and ask the important question of which biscuit is best!

What is your job role?
Project Archaeologist – I dig and record archaeology to the best standard possible

How long have you worked for Allen Archaeology?
Nearly 3 years

How would describe your excavation technique?
God like – controlled to get a good understanding of the archaeology I’m excavating and not to injure myself

How long have you been working in archaeology?
Almost 14 years

How did you get into archaeology?
My uncle was kind enough to get me on a job he was working at the time when I was 15 (16, I mean 16!) and I’ve been doing it ever since

What is the best thing about your job?
Archaeology is just like other jobs most days; but then you have those days out in the field where you come across something special, like an upper Palaeolithic blade. Those days make the wait till pay day or home time seem inconsequential!

Specialist skills?
I don’t really have a specialist skill; I’m more of an all-rounder, I know a bit of this and a bit of that!

Best site hut biscuit?
The hobnob (or the last biscuit in the pack!)

Digital techniques – Reflectance Transformation Imaging

Since starting at Allen Archaeology in September I’ve been involved with expanding our potential for digital recording and imaging. As you will hear in a later post, AAL have been using some techniques on site for a while but had not experimented with Reflectance Transformation Imaging (RTI).

A photo taken under normal lighting conditions

The same piece of wood viewed under novel lighting conditions and an acute lighting angle making the surface marks clearly visible

RTI is a technique which allows multiple images to be manipulated under varying lighting conditions to capture subtle surface information. Put simply when a surface is illuminated from an extreme angle it shows different information to a surface lit from above. By taking a series of photos from a single position but lit from different angles the images can be combined into an RTI, capturing a very accurate record of a surfaces shape. Imagine turning something in the light to discern changes in the surface. It can also allow the object to be viewed under novel lighting conditions allowing further information to be gleaned. Internet Archaeology have developed an online viewer with some examples here.

RTI has been used in research to record and study a whole range of objects and surfaces. Conservators have found the records useful in assessing the condition of artefacts (see here for some examples from the Smithsonian). While specialists in other fields have found the ability to compare artefacts located around the world has allowed their research to evolve (here are a variety of examples).

A normals visualisation of a pot from one of our sites

A normal visualisation of a Saxon pot from one of our sites

A close up of a coin under specular enhancement

At Allen Archaeology we have been using RTI as a supplementary record to photogrammetry, recording some of our particularly special finds. The results can then be sent on to our specialists to help them prepare our reports or to researchers with an interest in particular finds. They can also be used for us to send detailed information to our conservators in advance of the actual objects, helpful where objects are particularly fragile.

Chris and Josh having a go at capturing an RTI

The joy of RTI is it is quick, simple and low cost. The only equipment needed is a camera which can be used on a manual setting, a shiny ball (which the software uses to identify the position of the lighting) and a way of moving the lighting conditions (this can be a fancy remote flash or a light from a mobile phone). The software to combine the images is freely available (via the Cultural Heritage Imaging website).

Archaeology in the commercial world

The discipline of archaeology is as old, or older than some of the finds we dig up every day, with the first documented archaeological dig dating to the 6th century BC when the Babylonian king Nabonidus led excavations to find the earliest phases of several palaces and temples in ancient Babylon.

Roman colonnade discovered in Lincoln in 1878

In recent history, the discipline of archaeology began as a gentlemanly pursuit, with the profession gradually developing an increasingly scientific approach thanks to a number of scholars in Europe and America during the 19th century, such as General Pitt Rivers; a British soldier and adventurer, who brought military precision and organisation to the process of archaeology. Nevertheless many archaeological discoveries were still chance finds during development. In the 20th century, another military man, Mortimer Wheeler, also employed military precision in his numerous excavations in Britain and India, and helped bring archaeology to a mass audience through numerous TV and radio appearances.

General Augustus Pitt-Rivers 1827-1900

As the pace of development increased in the post-war years, the relationship between archaeology and development changed. It became apparent that many important archaeological sites were being lost, with little or no record. This led to the evolution of a whole new discipline of ‘rescue archaeology’ or ‘salvage archaeology’, which introduced new techniques to maximise the recovery of archaeological data with the limited time and resources available. This led to the development of a number of archaeological organisations, often based within and partially funded by local authorities, as well as by developers, to undertake these rescue digs.

Legislation was slow to catch up however, and it was not until, in 1990, with the implementation of PPG 16, the ‘polluter pays’ principle was applied to archaeology and development. This piece of planning guidance placed a burden upon the developer to ensure that archaeological remains at threat from development were adequately recorded, with that funding coming directly from the developer, and the work more often than not being secured by planning conditions. In some local authorities there was a feeling that more work should be undertaken pre-determination, both to limit future delays to construction programmes, and due to the concern that should important remains be exposed, there was little chance to offer them legal protection or record them adequately once a grant of planning permission had been issued. This finally manifested itself with the release of PPS5 in 2010, which placed greater emphasis on providing more information on a sites archaeological potential prior to submission of a planning application. PPS5 was short lived, but much of the guidance in PPS5 was adopted into the new National Planning Policy Framework in 2012.

The provision of developer funding for archaeology resulted in the development of numerous independent archaeological companies, and in recent years, the local authority based units have largely died out. Most companies nowadays are small, with tens of employees rather than hundreds, as well as numerous sole traders, particularly in the fields of specialist finds analysis. The fact that archaeology is developer funded also means that it is subject to competitive tendering to win projects, with the best price to fulfil the councils brief for the works usually being the winner. As such the whole process is very different to the preconceived notion of a cohort of academics and university students spending season after season studying every aspect of a single site in painstaking and minute detail. Furthermore, we can no longer choose where to go and what to dig up, rather, we are driven by the needs of our clients, so one week we may be excavating an Anglo-Saxon cemetery in Norfolk, then the next week Victorian tenements in Sunderland. Unfortunately, this also means we cannot, like academic research digs, restrict our digging to a few months in the summer, but have to be outdoors all year round, so a decent set of waterproofs and some woolly socks are a must!!

Hoeing snow at Sleaford Power Station

Because of the restrictions imposed by the nature of the industry, commercial archaeology can often seem a brutal process, with a lot of the heavy work undertaken by mechanical excavators, or a ‘big yellow trowel’ as they are colloquially known. That’s not to say there is not a lot of manual work after that. As soon as the topsoil is stripped off a site, its down to the mattocks, spades and shovels, and yes the trowels do still make an appearance as well. An experienced archaeologist can move a remarkable amount of soil with a trowel, and they have also been known to come in handy for cutting birthday cake in an emergency!!

In the 21st century, development led archaeology represents by far the majority of archaeological work undertaken in the UK, and the fact that this archaeological work is driven by the location of new developments, rather than a research focussed programme intended to test or prove a certain theory, has resulted in a new understanding of the country’s history and heritage, often leading to reappraisal and revision of traditional theories. The vast majority of the output of commercial archaeology is in the form of reports required by the planning authority, ‘grey literature’ as it is known, with only a minority of key sites reaching formal publication. However, numerous attempts have been made by academic researchers and commercial archaeologists alike in recent years to collate and interpret this ever growing body of data to further the understanding of the finite archaeological resource that lies beneath our feet.