Agenda - 01-04-1988 - Laserfiche WebLink

Browse Search

s - -- 034 • EFFLUENT PUMPING For maximum corrosion resistance. EQUIPMENT FOR the discharge piping, junction box PRESSURE SEWERS and shutoff valve are made of plastic materials. Mercury ball level controls In grinder pump pressure sewer are standard.Some engineers speci- • systems there has been only one size fy a redundant check valve to be lo- centrifugal grinder pump (2 hp) avail- cared in service line for added • able for installation at the individual protection. An anti-siphoning valve home. However, in a STEP pressure is added to the internal piping if low sewer, the engineer can choose from heads or negative heads (downhill a a variety of horsepowers and sizes. runs) are expected to prevent any STEP pumps can be 1/3, .4, 1/2, 1, siphoning action. In most cases, the 1-1/2 and 2 hp, depending on the cover is made of steel so that it can head and flow requirements. The per- withstand the weight of a riding lawn formance, weight, and cost of the mower. Pump basin covers are nor- ) STEP pumps increase as horse- mally installed flush with the ground power increases. The STEP pumps level. An anti-flotation flange held that are available are basically sump by concrete is provided to prevent pumps, small hp sewage ejectors or the basin from moving upward in . modifications thereof. , highwater table areas. 1 One of the drawbacks of currently 1 available STEP pumps is that they generate much higher flows than PERFORMANCE needed. As an example, a 1/2 hp $ STEP pump can generate up to 80 Since STEP pumps are pumping a gpm with shut off heads to 78 feet. clarified liquid from a septic tank, 4 Since the peak wastewater flow there is usually very little problem generated from an average individual with the pump plugging.The risk of home is no more than 8-15 gpm, you plugging is greater if an old septic can see that the flow rates are much tank is used which is generating higher than needed. The high flow heavy flows and possibly some carry i rates make it more difficult to hydrau- over solids due to infiltration. lically design a pressure sewer and will increase pipe sizes. In addition, .At one time, it was assumed that the high flow rates of the standard a high percentage of old septic tanks effluent pumps can create problems could be utilized as part of a STEP 4 when discharging into a variable pressure sewer. Now, the consensus gravity sewer system. of opinion is that the majority of old $ septic tanks should be replaced Septic tanks can be made of fiber- with new ones. One of the problems in using old septic tanks is the clues- ) glass,polyethylene or concrete. Con- tion of how do you determine if the crete is the most readily available. tank is leaking. By the time you 4 The most common size used is 1000 pump out the septic tanks, find the gallons.although 500 and 750 gallon leak and repair it (assuming this can 9' size tanks have been used in some be accomplished), it may be less pressure systems. In commercial expensive to put in a new septic tank. applications,larger size septic tanks - i will be required. Two potential problems associated Variations of an audio and visual with STEP systems are corrosion l alarms are used, although the Most and odors. As previously indicated. - . corrosion can be overcome by 1 flashing popular aln m I st-ht emounted ion con- - choice of materials. Since the septic trol panel. Most all control panels tank is vented through the house with a disconnect switch are located plumbing system, no outside venting is required. Care must be taken to outside so they will be easily acces- . insure the Cover to the wet well is - sible to the serviceman. The prefer- sealed properly. Odors can be a able location of the panel and alarm problem at intermediate pump sta- is on the side of the home or garage tions if vented to atmosphere. This to minimize aesthetic concerns of the home owner. If desired, the can solved g installing an under- groo panel can be located at the septic ground venting system. - tank/pump basin and mounted on a pedestal. _CRAIG S.MORGAN AND ASSOCIATES,P.A.- 3 Al