Guidelines for ExcavationsExcavations
Similar concerns with regard to surface aspects of groundwater and drilling apply to excavations, and the same approach should be used. If possible the work should be done in dry weather, and surface runoff water diverted around the trench or trial hole. A photographic record should be kept for all sites, showing the situation before, during, on completion and after a suitable rehabilitation time has elapsed. Care in planning the actual trench work is also needed from a safety aspect, information regarding which is obtainable from the Health and Safety Authority, Hogan Place, Dublin 2.
Excavation should not take place adjacent to streams or rivers which are potential spawning grounds for fish species. If possible, excavations should also be avoided in fields with old 'french drains'; if encountered they should be correctly replaced.
A temporary fence must be erected around any excavation, equipment and spoil heaps. The fence should be at an appropriate distance beyond the opening, and no chemicals/petroleum-based products should be kept in this area. Unless otherwise agreed with the landowner the fence should be adequate for the purpose of excluding any livestock kept on adjoining land. All temporary fencing should be erected in position before excavation commences and subsequently maintained until reinstatement of land is completed.
If pumping is necessary to prevent excavations from becoming waterlogged, the discharge must be directed into suitable drains or onto stable slopes, and not directly into receiving waters.
All topsoil should be kept separate and stacked to one side of the working area and kept free from the passage of vehicles and plant. In sensitive areas of vegetation, sods should be taken and carefully preserved for reinstatement. Subsoil and hard-core materials should be kept separate from topsoil. Contaminated soil should be clearly identified and remediated.
Reinstatement of land must be carried out without delay, according to best contemporary environmental practice. After backfilling, the topsoil should be carefully replaced, and additional topsoil provided if reasonably required for proper reinstatement. Care should be taken to restore ground to a condition at least equivalent to that existing before the commencement of the works. This should involve the topsoil being left in a loose and friable condition; appropriate levelling off of the ground so as to present a neat appearance (the level of the trench area should be the same as that of the undisturbed surrounding ground one year after restoration is completed); the removal of all stones in excess of 50mm (2") in diameter from the surface; and the reseeding of the area in consultation with the landowners. The rate of seeding and time and method of sowing including application of fertiliser, should be in accordance with good agricultural practice.
On completion of the works the company must remove all temporary buildings, fences, roadways, all surplus soil, stones or gravel and any debris such as trees, brushwood, etc. and any other matter that does not naturally belong to the site. The site should be left clean and tidy, to the satisfaction of the landowner, and if required by the landowner, the company should plant shallow-rooted trees, shrubs, or hedging to replace any which have been removed. If compensation is required, it should be finalized without delay. Follow up visits should be made after 6 months to assess the quality of restoration, and any required remedial work undertaken to the satisfaction of the landowner.
If it is intended to keep open excavations after completion of prospecting and exploration work, it may be necessary to get planning permission, either on a temporary or a permanent basis, as appropriate. Advice must be sought from the Local Authority.