24th October 1977
Joint Meeting with the Institute of Quarrying Held at Burlington House.
The Quarrying Influence on Groundwater Resources Defined in Theory. By R. Aspinwall.
The paper was aimed at presenting to the quarryman the theoretical hydrogeological principles which may obtain at quarry sites, principally in the UK.
The hydrological cycle and its relevance to quarrying was explained and illustrated with slides at two ‘model’ quarry sites. The first site represented the quarrying of a simple aquifer whose sole recharge area was the areal extent of the deposit exposed to infiltration. The second site represented the quarrying of a simple valley aquifer whose recharge was derived not only from precipitation but also by bank storage and lateral leakage. These models were then discussed with reference to
(i) meterological processes
(ii) infiltration processes
(iii) groundwater occurrence
(iv) surface run-off
and the concept of a hydrodynamic balance was explained.
The effects of disturbing this hydrodynamic balance were illustrated by slides. The principal changes in the balance were considered to be:
(i) quantitative effects of extraction
(ii) quantitative effects of dewatering by pumping
(iii) qualitative effects of extraction and dewatering by pumping including saline infiltration problems
(iv) quantitative and qualitative effects of backfilling with restoration materials, including putrescible wastes.
Hydrogeological Aspects of Sand and Gravel Quarrying—Two case studies. By A. de Fleury and D. Sharman.
The two cases described were chosen by the authors to illustrate the different approaches required in two areas, the first in southern England and the second in