To protect investments and manage risks associated with storing manure, operators should inspect facilities more often in dry conditions.
‘Confined feeding operators and livestock producers invest a lot of money to construct berms, manure storage and catch basin facilities to protect groundwater and surface water,’ says Vince Murray, AOPA engineer with Alberta Agriculture and Forestry. ‘Dry conditions can negatively impact the integrity of these facilities. To protect that investment and to manage the risk associated with storing manure and manure impacted runoff, operators should inspect the facilities more frequently during dry conditions.’
The Agricultural Operation Practices Act (AOPA) requires operators to construct liquid manure storages or catch basin facilities so that the inside, bottom and outside walls are protected from erosion and damage, and to maintain the physical integrity of the liner or protective layer.
‘As evaporation rates increase, the volume of liquid in manure storages and catch basins will decrease. This can expose more of the side slopes than normal, and in extreme cases, the bottom of the storage facility,’ explains Murray.
Exposing a clay liner can result in shrinkage and cracks forming in the liner. The exposed and dry side slopes are also more susceptible to erosion during precipitation events. Operators with synthetic liners should inspect for any damage (rips and tears) caused by agitating or pumping and consult the liner’s supplier for the best method to maintain its integrity.
Exposed manure storage or catch basin slopes are also at risk of infestation of burrowing animals and the establishment of vegetation like weeds, shrubs and trees. Roots and burrowing animals can damage the liner and leave conduits for manure to flow down through the protective liner which can increase the risk for groundwater contamination.
‘To minimize these risks, operators are encouraged to monitor and inspect their liquid manure storages and catch basins on a regular basis for any erosion or damage to the liner and repair as required. In addition, take care to control vegetation growth on the slopes and fill in any burrow holes,’ says Murray.
If liquid levels are low, operators may want to take this opportunity to remove sludge build-up that is on the bottom of the facility. Sludge reduces the storage volume of the facility which increases the risk of overflows or emergency spreading.
If an operator runs into any issues with their facility arising from dry conditions and needs assistance, they are encouraged to contact the nearest Natural Resources Conservation Board field office for support.
Source : alberta