A wastewater system in Northern Virginia treating 3 MGD with 4 x 0.75 MG SBRs. The decant from these SBRs goes to a 2 Acre polishing pond. The effluent then stays in that lagoon for roughly 5 days before it proceeds through the chemical coagulation, disinfection and stream discharge. In the past, the SBR decant (generally from poor winter time operation) has sent many pounds of TSS over to the 2 Acre polishing pond. Over the years the solids layer began to build and fill in the pond. For years solids build up in this aerated pond up until the point where solids levels were clearly visible in some areas. The pond also contained lots of foam and often suffered from ammonia spikes likely caused by endogenous respiration from the settled sludge.
Maryland BioChemical surveyed the system and proposed a BioSpike program to reduce the accumulated levels of sludge. The program was implemented (along with a quick dose of Lake Releaf) during the Spring/Summer of 2015. A dose of 8 cases per month was implemented for 3 months.
The program achieved the following results:
- In less than 1 month nearly all of the foam that had just about covered the entire pond had vanished
- The ammonia spikes ceased almost immediately
- The accumulated sludge decreased by as much as 3 feet in some spots, averaging -1.8’ over 2 acres
- Also they were able to finally see a submerged pipe