Between drains, pumps, plumbing and maintenance ports, mining ponds often feature multiple penetrations through the sides and bottom of the geomembrane liner. Handling the use of pipes and other penetrations properly will extend the lifespan of the liner. These openings are some of the most vulnerable parts of the pond and are at higher risk for leaking than the rest of the material. Try these tips to minimize the chance of repairs around penetrations through a monolithic liner.
Placement is often what makes or breaks a particular penetration through a liner. How easy is it to access the pipe or pump after you install it? How much foot traffic is necessary to reach each penetration? Will you only place them where the pond needs full drainage for maintenance, or can some be in shallow areas that are more accessible? Even just spacing these features out so there’s plenty of solid material between them will make a big difference in the likelihood of leaks.
Using Matching Boots and Covers
Boots and covers that slip down over the penetration and connect to the liner work best at closing up any gaps in the material. You’ll need a boot or cover that is made of a compatible material to ensure it bonds tightly to the bottom liner. Generic boots may not seal tightly and could create leaks that are hard to find. Check these connectors regularly to ensure they’re still doing their job. Many penetration covers are designed to handle the same electrical testing that is used on the geomembrane seams to detect leaks. Plan for maintenance and inspections while designing your mining pond and you’ll find it much easier to work on over the years of its lifespan.
Limit Buried Plumbing and Pumps
Since many mining ponds require bottom drains to remove leachate or wastewater as needed, it’s often tempting to bury the necessary plumbing and pumps under the pond too. But before you do this, consider the amount of work it takes to drain the pond and excavate this buried equipment. Run plumbing as close to the surface of the ground surrounding the pond instead, so it’s easy to access when there’s a clog or leak. Pumps should definitely stay above ground for maintenance and repairs, which are usually needed at least on an annually basis.
The right mining geomembrane won’t develop leaks just because you’re having to cut openings for pipes and drains. RPE products from BTL Liners are tear resistant due to the reinforced design, so there’s no concern about cut edges deforming under pressure. It’s also easy to seal boots and other covers around any penetrations going through the liner.