Groote Haar (2015)

The Great Hair in 2018.

In November 2015, Archeodienst BV carried out an extensive desk and drilling survey at this location for the construction of the access road to the planned Groote Haar industrial estate north of Gorinchem.

Based on the results of the drilling investigation, Archeodienst considers further investigation to be necessary in various parts of the area if digging is carried out deeper than indicated in Figure 1.

Based on the results of the drilling research, zones remain that retain a (medium) high expectation. Also, a part of the plan area has not been investigated, where (medium) high expectation zones may still occur.

Figure 1.

The (medium) high expectations on site of the (banks of) crevasses applies to the Mesolithic and Neolithic period. Since possible remains from the Mesolithic and Neolithic are expected, a mapping drilling survey is carried out for medium to large Stone Age settlements that are characterised by an archaeological layer using method B2 from the mapping survey guideline 1Tol, A.J., J.W.H.P. Verhagen, M. Verbruggen, (2012)
Guideline for inventory field research version 2.0. Part: mapping drilling research, Gouda (SIKB edition)This method involves drilling in a 20 x 25 grid with a gouge with a diameter of 3 cm.
An additional advantage is that the boreholes already drilled have the same borehole diameter and the 20 x 25 m grid can be laid over the used 40 x 50 grid. This means that only additional boreholes need to be drilled (four around a borehole with a bottom) and existing drilling locations do not need to be re-executed.

donk

If these four boreholes are dug deeper than the indicated depths or if the plan area needs to be investigated to the maximum excavation depth, further investigation is recommended. The advice is to map the soil level around these 4 boreholes and determine whether there are indications of an archaeological site in accordance with the above method. This means that at least 16 mapping boreholes are required (4 boreholes per borehole with a soil level). If a soil level occurs in one of the mapping boreholes, the mapping around that zone must be continued until no more soil levels are found.

Based on the results of the drilling research, no reliable statement can yet be made about the archaeological expectations at the location of the donk and the location with historical buildings.

Figure 2.

Of the 8 boreholes with a bottom level, there are 4 boreholes (26, 185, 278 and 280) where the potential archaeological level lies within (the buffer zone of) the maximum excavation depth.

At the donk, a possible archaeological level could be close to the ground level and, in addition to settlements, camps of hunter-gatherers (flint site) are expected. In order to find a medium-sized flint site with a moderately high find density, it is recommended to place boreholes with a diameter of 12 cm in a borehole grid of 13 x 15 m. The drilled river dune sediment is then sieved over 3 mm (method A32Tol, A.J., J.W.H.P. Verhagen, M. Verbruggen, (2012)
Guideline for inventory field research version 2.0. Part: mapping drilling research, Gouda (SIKB edition)). There is a distance of 302 m between boreholes 303 and 50 and the working strip is 20 m wide here. It is recommended to first check with 2 exploratory boreholes whether a ground level is present. If a ground level is present within 1,8 m (max. excavation depth + 30 cm buffer) it is recommended to map the donk in accordance with the above method. This would then result in a maximum of 5 mapping boreholes. Since the donk has already been included in the design for the access and exit ramps, the chance that plan adjustment is possible is considered small.

Advice

If work is being carried out around the historical buildings, it is recommended to place a row of three exploratory boreholes. One in the middle of the expected buildings (yard of approx. 20 m wide) and a borehole 30 m east and west along the path. This will allow us to determine whether the soil structure at the location of the expected buildings deviates from the surrounding region. If the soil structure is the same, the construction of the path will have disturbed the archaeological level. If the soil structure deviates, this is an indication that there may still be archaeological remains.

A large part on the eastern side of the plan area could not be investigated due to the lack of access permission. If this zone proves necessary for the development of the access road, it is still recommended to carry out an exploratory drilling investigation if excavation work takes place that goes deeper than 1,0 m –mv.

In addition, it should be noted that the above advice assumes a maximum excavation depth of 1,5 m. If deeper excavation work is required, the need for additional archaeological research must be tested against the advisory map.