Literature Review and Field Experienceon Methods of Estimating Seepage or Leakage from Unlined Ponds, 2001 Environmental Conference Proceedings

Kevin A. Kahmark, C. Van Maltby--The pulp and paper industry operates a significant number of unlined surface impoundments (unlined ponds) including aerated stabilization basins, tertiary ponds, polishing ponds, quiescent basins, and equalization basins. As part of the technical studies program, NCASI reviewed published seepage estimation methods for their utility in documenting the performance of these basins. While NCASI limited the literature review to post-construction or in-situ seepage measuring techniques of unlined or natural earthen-lined ponds, several preconstruction methods were identified.

Techniques identified in the literature include seepage meter, infiltrometer, or piezometer installations, water-balance methods, tracer studies, and numerical simulations. Two methods that emerged with potential application to the paper industry are seepage meters and infiltrometers.

Discussion with several geotechnical experts indicated that conducting field trials with a modified seepage meter would provide the best approach to measuring the seepage of an in-use unlined lagoon or surface impoundment containing long-term deposition of suspended material.

Field trials at two pulp and paper industry lagoons confirmed that modified seepage meters could be a useful tool in measuring the seepage.