Industry FAQ

Q: What is the optimal pump sizing criteria for varying household sizes?

A: Pump sizing is primarily determined by estimated daily wastewater flow. A typical rule of thumb is 75 gallons per person per day. However, this must be adjusted for local regulations, fixture counts, and anticipated peak flows. The pump must be capable of delivering the required flow rate against the total dynamic head (TDH) of the system, including elevation differences, pipe friction losses, and pressure requirements at the drainfield. Undersized pumps will lead to insufficient effluent distribution, while oversized pumps can cause excessive wear and energy consumption.

Q: How do I mitigate the risk of drainfield biomat buildup and subsequent clogging?

A: Mitigating biomat buildup involves several strategies. Regular septic tank pumping to remove accumulated solids is crucial. Installing an effluent filter prevents larger particles from entering the drainfield. Avoiding the disposal of excessive amounts of fats, oils, and grease (FOG) is essential. Ensuring proper drainfield loading rates, based on soil permeability, minimizes hydraulic overloading. Utilizing a drip irrigation system for effluent distribution can improve biomat distribution and reduce clogging potential.

Q: What are the key considerations for selecting corrosion-resistant materials for pump components?

A: Wastewater is a highly corrosive environment due to the presence of hydrogen sulfide (H2S), sulfates, and organic acids. Stainless steel (316SS) is a common choice for pump impellers and wet-end components, offering good corrosion resistance. Engineered plastics like Noryl or polypropylene are also suitable for certain applications. Coatings, such as epoxy or polyurethane, can provide additional corrosion protection for metallic surfaces. Regular inspection for corrosion is vital, and timely replacement of corroded components is necessary.

Q: What alarm systems are recommended for pump septic systems, and what parameters should they monitor?

A: Recommended alarm systems include high-level alarms in the pump tank to prevent over-pumping and pump failure, and pump run-time alarms to detect pump malfunctions. Monitoring pump amperage can indicate overloading or impeller blockage. Additional alarms can be incorporated for filter blockage and effluent level in the distribution box. Remote monitoring systems with cellular communication provide real-time alerts and enable proactive maintenance.

Q: How does soil type influence drainfield design and performance?

A: Soil type is a critical factor in drainfield design. Soil percolation rates determine the hydraulic loading capacity of the drainfield. Well-draining soils (sandy loam) allow for higher loading rates, while poorly draining soils (clay) require larger drainfield areas or alternative treatment technologies. Soil texture affects the rate of oxygen transfer and microbial activity, influencing effluent treatment effectiveness. A thorough soil analysis, including particle size distribution and percolation testing, is essential for proper drainfield design.