Site investigation study Recommendations Contract Title New restaurant and ice cream parlour Report Title Site investigation study Revision 1A Status Issued Record of Issue Issue Status Author Date 1A Issued for comments Rhys Boots 13/12/19 Desk Top Study 1 Purpose of Desk Top Study 1 Site Description 1 Site Access 2 Historical Background 2 Unexploded Ordnance survey 3 Ground Conditions 4 Local Environment 5 Local Radon 5 Local flora 5 Local water course’s 6 Limitiations 6 Recommendations 6 Non-intrusive surveys 6 Intrusive surveys 7 Trail pit 7 Boreholes 7 Foundation 8 References 9 Desk Top Study Purpose of Desk Top Study The purpose of this desktop study is to provide information for the new ice cream parlour construction as well as provide a recommendation of the investigations to be carried out on the area. In this document there will be a history of the site, of the local environment, the proposed site its limitations and access and the recommended intrusive and non-intrusive investigations to be undertaken. Recommendations for which foundation type is most suitable will also be included in this report. Site Description The proposed area for the construction of the new ice cream parlor/ restaurant and managers apartment is located between the Marriot hotel and the Swansea county hall. As shown in the image below and marked up showing a proposed outline of the location of the new build. The site has a mixture of green grassed area and tarmac, the tarmac area of the site would be the car park used by the Swansea County hall as seen below between the red outlines area and the county hall building. Proposed location map (Digimaps, n.d.)   Site Access The access to the site is off the a4067 (Oyster mouth road) and on to Dunvant place. From this road there is 2 possibilities for access, ether by following the road passed the county hall to the car park or as a secondary option. Would be to make a haul road across the green banking as it would cause the least disruption for local area and for road users. This would need to be checked with the local authority as to who has ownership of this land and if it would be acceptable to do so. Please see the below marked up traffic management plan (maps, 2019). Red arrow being main access and blue being proposed secondary access. Road map (maps, 2019) Historical Background From research at the Swansea county hall archives it shows that the of the area for the new proposed restaurant and ice cream parlour with a manager’s apartment had various historical uses. The main use was a rail way, which tracks ran across it as shown in the historical map below. The Railway ran along the coast line. It would carry various items just as coal, copper, ordnance, passengers. Most of these would head for the docks. It is also shown in the map that there is an engine shed in the near area to the location of the proposed new build. Shown on the map below there is also tanks located at the far end of the county hall and a large tank near the engine shed it is unclear what was kept in these but given the closeness to the tracks it may be possible this ether contained fuel/ water or coal. It is also believed these may have been buried to protect them from the bombing that took place during World War 2 which was common practise. This could mean that there is a risk of these still being buried or some construction relating to these may still be hidden in the soil. It also adds a risk of possible historical damage to these tanks leading to its contents contaminating the ground. Historic Map of proposed location. (Council) The area was largely covered by railway tracks these tracks have been removed but there is possibilty that due to the length of time these tracks where in use, that there may be left over materials that have fallen off of the trains coming through this section of tracks or tracks left buried . Unexploded Ordnance survey During the second world war large sections of Swansea was destroyed during the blitz, as shown in the image below (Dean, 2013) shows in light grey the areas that were destroyed by the bombing and in red are the new streets that have been constructed since. There is the chance of an unexploded ordnance being in found in the proposed area. Historic map of Swansea overlaid with new streets   The below image is taken from (digi maps, 2019), it shows the proposed location for the new construction. An ordnance survey that was undertaken by the Uk government shows that the area is supposedly clear. Given it has no markings or indications to show something was found or remaining in the area shown below. Map of ordnance detection (Digimaps, n.d.) Ground Conditions Investigating into the records that have been submitted online on digi maps (DigiMaps, 2019 ). This shows that the local area has a bedrock with suspected mudstone, siltstone and sandstone and has varying superficial deposits of sand and sections of artificial deposits (these artificial deposits may be from landscaping works from surrounding buildings/ demolition or previous work that has been covered over.) Map of soil classification (DigiMaps, 2019 )   Local Environment Local Radon While looking into the location and investigating its history a check on the potential of radon gas in the area was undertaken. Looking at the ukradon mapping website it was found that the proposed site is describe as having a 1-3% radon potential this can seen in the image below taken from the Uk Radon website. As shown by the legend in the bottom right of the image, it shows that the location is in the area of 1-3% this means that there is a a higher indication of radon but it is expeted to only be a 1-3% increase on the local background readings expected. Map of radon detection (UKRadon, 2019) Local flora The proposed location for site has various tree species located in and around the area in which the project would take place. Looking into whether there is any Tree preservation orders in place contact with the local authority was made and as shown below a reponse from the local authority (Webster, 2019)which states there is no TPO’s in place for the are around the civic centre/county hall and marriot hotel. Email from Swansea council Local water course’s The area is located near the sea front. With the sea front so close by there may be restrictions to work carried out espically in the soils. With the sea so near by it the water table needs to be considered with regards to the foundation and any works being carried in the ground and dewatering techniques may need to be considered. Limitiations The proposed location for the project has no limitations and restrictions set on the land by the local council. Due to the location and proximity to the sea front and the surrounding buildings such as the Marriot hotel certain restrictions may be enforced, such as set delivery times, set working hours. Recommendations While investigating into the proposed area of the new construction there are certain elements and key areas in which It is recommended more in-depth intrusive and non-intrusive investigations are undertaken. Non-intrusive surveys The first recommendation is a survey to be carried out on all drainage and a drawing to be marked up of services that run through the site. As shown, there are man-hole covers in the proposed location that were observed on a site walk around. The run of these services/drainage are unknown. This survey is to be carried to prevent any accident or incidents of striking or encountering services while undertaking the ground investigations. It is my recommendation that an unexploded ordnance survey is undertaken, this survey is carried out using a GPR (ground penetrating radar). depending on the equipment depends on the depth it can detect any unexploded ordnance .  Intrusive surveys Trail pit It is of my recommendation that trail pits are to be carried out as part of the site investigation. This would be the first intrusive investigation to be undertaken to establish the soil classification, the soil stability within an excavation, the water content of the soil amongst other data. A trail pit investigations data is combinable with other investigations to help with the design of the foundations. I advise that there are 6 trail pits to be carried out, 5 of which are to provide a cross section across the proposed new build and a 6th to undertaken in the location nearest to the chemical works. This is to provide any data if there is any contamination in the soil from the works. The setting out of these trail pits may change depending on the findings of the previous surveys that have been recommended. The trails pits should have a depth of at least equal to if not greater than the proposed foundation depth. The pit should have supportive measure in place if it believed the soil will have a low stability. This is covered/ enforced under regulation 22 (excavations) and 24 (reporting and investigating) of the CDM Regulations (CDM, 2015). Boreholes As part of my recommendation for the soil investigation I recommend Bore hole investigations be undertaken to establish the depth and different layers of soil more accurately in the proposed location. Specifically, it is recommended based on the data found that open hollow stem auger would be the bested suited to carry out the investigations. The reason for this is due to the type of soil being mainly of a sand/silt that this type of auger drilling would allow the displaced soil that the auger brings to the surface but also allows for access to an undisturbed sample in the centre of the stem. An auger drill rig is commonly one of the smallest sampling rigs this would be beneficial due to the busy roads and proposed area. As another recommendation that the rig be an off-road type this will allow it to access all areas with ease. Notice must be given for this operation to be carried out as set out in “the bore hole sites and regulations 1995 (HSE, The bore hole sites and operationsregulations , 1995) while carrying out the operations these regulations are to be adhered to. It is by this report’s recommendation that due to the regulations set out by the HSE, that there is a wide range of drilling operations it covers, and these regulations must be adhered to while carrying out any drilling operation. For the proposed site it is likely that there is no specific regulations other than if the hole bored is deeper than 30 meters (HSE, HSE.GOV.UK, 2008) but it is advised that while carrying out these works that the contractor undertaking them is fully trained competent and has an in-depth knowledge of these regulations There are other restrictions for drilling for example see the attached table showing details and what regulations apply to them. (HSE, HSE.GOV.UK, 2008) Foundation Due to the information found in this desk study it is recommended that due to the soiling being a high capacity of sand that the bearing capacity could be poor. For these reasons this report advises that the foundation be a raft on pile foundation. The reason for this is a pile foundation is the best type of foundation in poor soil or soil with poor bearing capacity. The depth of these piles will need to be specified by a trained and competent person based on the information gathered from the ground investigations. A raft on pile foundation will be not just the best in this type of spoil but also provide with the raft the flat surface to carry out building the superstructure. This recommendation is based on information found via this report, the design of this foundation may have to change based on the information acquired after undertaking the ground investigations. References Boots, R. (2019, 12 02). Raft on pile foundation. Raft on pile foundation . Pontypridd. CDM, H. (2015, june 01). HSE - CDM. Retrieved from HSE: http://www.hse.gov.uk/construction/cdm/2015/index.htm Council, S. (n.d.). Land and mapping . Dean, G. (2013, june 1). The swansea Blitz. Retrieved from city wintess: http://www.medievalswansea.ac.uk/en/blog/aerial-photograph-of-swansea-1949/ digi maps. (2019, 11 01). digimaps OS ROAM. Retrieved from digimaps: https://digimap.edina.ac.uk/roam/map/os DigiMaps. (2019 , december 04). Digimaps geology. Retrieved from Digimaps : https://digimap.edina.ac.uk/roam/map/geology Digimaps. (n.d.). Digi map os roam. earth, g. (2019, novemeber 21). google. Retrieved from google earth: https://earth.google.com/web/@51.61458685,-3.94794991,5.63563368a,1409.98181477d,35y,18.92284586h,10.08424601t,360r HSE. (1995). The bore hole sites and operationsregulations . london: hse. HSE. (2008, october 1). HSE.GOV.UK. Retrieved from HSE website : http://www.hse.gov.uk/pUbns/priced/l72.pdf maps, g. (2019, december 04). google maps . Retrieved from google : https://www.google.com/maps/place/Swansea+Civic+Centre,+Swansea+SA1+3SN/@51.6137069,-3.9501635,17z/data=!3m1!4b1!4m5!3m4!1s0x486e8acb8f3f33cd:0x63c31093ec089c2f!8m2!3d51.6137036!4d-3.9479748 UKRadon. (2019, 11 24). Ukradon radon map of uk. Retrieved from UKRadon : https://www.ukradon.org/information/ukmaps Webster, A. (2019, 11 29). FW: Form Submitted. Swansea, Swansea and Neath, Wales.