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A&P CONSULTING TRANSPORTATION ENGINEERS, CORP. GOLDEN SHORES PUMP STATION REHABILITATION (CCNA) RFQ 18-11-01 14 Cleaning and Video InspectionAfter an assessment of the existing system, it may be necessary to remove any accumulated sediment, trash, or other substances from various components of the storm drainage system. Some common pollutants found in storm drains include: trash and debris, sediments, oil and grease, antifreeze, paints, cleaners and solvents, pesticides, fertilizers, animal waste, and detergents. This cleaning is necessary to eliminate amount of pollutants, trash, and debris both in the storm drain system and in receiving waters. Clogged drains and storm drain inlets can cause the drains to overflow, leading to increased erosion. Cleaning increases dissolved oxygen, reduces levels of bacteria, and supports in-stream habitat. One of the main methods of cleaning utilized in storm sewers is involves jet/vacuum vehicles which can be used to remove debris from stormwater catch basins and pipes. This equipment breaks up clogged/accumulated material with high-pressure water jets and vacuums the material from the sewer. Water used in storm drain cleaning must be collected and properly disposed of, typically at a sanitary wastewater treatment facility. Pipe RehabilitationIf the drainage pipes are found to be in poor condition due to wear or structural damage, there are several methods that can be utilized depending on the condition or situation presented. The original assessment of the pipes should determine if there is any unwanted leakage, worn out joints, etc. A repair process can then be recommended. Below are some examples along with summaries of what the process entails. 1. Chemical Grouting: Ideally suited to stopping leakage and reducing soil loss, grouting consists of injecting a self-setting grout into structurally sound leaking joints or small wall cracks2. Sliplining: When existing capacity is sufficient, sliplining is a relatively cost-effective rehabilitation method in which a pipe is inserted into an existing line by either pulling or pushing continuous or short-length pipes.3. Cured-in-Place Pipe: A polyester flexible sock or sleeve impregnated with resin is inverted or winched into the pipe.4. Fold-and-Formed Pipe: This method uses deformation to reduce the pipe diameter of conventionally formed pipe. The new pipe is then pulled into the existing pipe in the manner of traditional sliplining. Once winched into place, the pipe is expanded back into its original shape, forming a close fit with the existing pipe.5. Pipe Bursting: Pipe bursting uses a pneumatic or hydraulic bursting mandrel to crush an existing pipeline while pulling a new pipe into place. The crushed pipe is forced into surrounding soils, acting as bedding material for the new pipe. Drainage WellsBecause of the nature of drainage wells and their form of operation it is essential that the groundwater table be analyzed to determine if operation as is may be continued. Cleaning of Drainage WellsThe well should have all retained water removed, so that it can be cleaned well physically. The well lining can be cleaned manually using a brush and chlorinated water, or by using jetting or surging techniques also applied for well development. The reason drainage wells and its parts should be cleaned regularly is that when enough sediment flows into the dry well, it will begin to leach into the surrounding soil and affect the well’s capacity to filter and drain the water. When built-up sediment within a dry well is left too long, it will eventually degrade its performance and cause failure, even if the utility was sized and installed correctly. The drainage wells should be cleared of any debris or obstruction to ensure continued operation. Redevelopment/RehabilitationWhen drainage wells are found to be in need of redevelopment to ensure proper operation, there are several methods that can be used to accomplish this. • Over-pumping: This method entails pumping the well at a rate greater than in normal operation and generally develops the more permeable sections of the surrounding environment