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HomeMy WebLinkAbout2005 [06] Jun 01 I I I I I June 1, 2005 Page 1 of 4 Pursuant to due call and notice thereof, the City Council for the City of St. Joseph met in special session on Wednesday, June 1, 2005 at 3:00 PM in the SI. Joseph City Hall. Members Present: Mayor Richard Carlbom, Councilors AI Rassier, Dale Wick,' Ross Rieke. City Administrator Judy Weyrens. Citv ReDresentatives Present: City Engineers Joe Bettendorf and Tracy Ekola, Dick Taufen, Mike Sworski, Jeff Ledin, Todd LaVold, Duane Day, Tom Wesolowski, Darrell Schneider New Water Treatment Facilitv: Jeff Ledin moderated the meeting, noting that this was a work session to show the City where SEH has progressed with information gieaned from earlier meetings. i Tom Wesolowski, SEH Process Engineer, briefly reviewed the layout of the building based on proces$ concerns. Two drawings were handed out illustrating the structure from the process angle. These are I attachments 1 and 2. Attachment 1 is of the lower level of the plant, which includes the backwash recycle tank, the clear well, the pump room, chemical feed rooms, and the meter repair room. Attachment 2 1 includes the detention tank, the filters, the plate settler, the pipe galleries, the sludge tank, and other 1 offices and control rooms. The site has provided some difficulty, with the area ground water only being two (2) feet below the 1 existing ground surface. This precludes the ciear well being placed underground, which is normally hoi.v SEH would design the plant. The Minnesota Health Department does not allow for a portable water 1 storage tank being placed into ground water. Similarly, it is less desirable to construct the Backwash Recycle Tank below the ground and into the ground water. Costs for dewatering during construction can escalate costs needlessly. I I The Council brought up·a concern regarding extra costs for the tanks being above grade. SEH i acknowledged that there are additional costs for additional exterior wall coverings, which would be over and above traditional in-ground storage tanks. However, SEH believes this easily outweighs the additional costs should the building be lowered and spread out over more area. i , 1 During the pilot study of the water found in the area, it was determined that the iron content is higher tl)an at previously considered sites. The iron found is around 2.0 ppm, and the previóus values have been 1 around 1.0 ppm. This additional iron makes it more imperative that the process include detention time prior to filtration. This allows for better coagulation of the iron, making it easier to filter during the filtration part of the process. The new layouts include the necessary detention tank. I Also with the higher iron content, more iron sludge will be produced during the backwash of the filters. ¡ This sludge will also be more difficult to handle. With these parameters in mind, SEH has looked into the inclusion of a plate settler in the process train. The inclusion of a plate settler is two-fold. One, it will i thicken the sludge requiring less storage for the sludge. This is important since there is no sanitary seWer available at the site. Second, less backwash recycling storage is required. This is due to the ability to 1 recycle backwash immediately after backwashing. Normally, a rest period is required prior to pumping water from the recycling basin and into the process train. Due to the rest period requirements, normally the backwash basins are sized to hold the volumes of two backwash cycles. i 1 On-site sanitary collection was discussed at this time. There will be no on-site sanitary sewer treatment system. It is not desirable to have an on-site treatment amidst the City's well field. Instead, on-site i sanitary sewage will need to be collected and stored in a holding tank. This will require periodic pumpi~g from a septic hauler. SEH will work on sizing this tank for convenient pumping. Having a split-level arrangement with a lower level fully accessible to people and vehicles allows for chemical feed rooms to be located in the lower area. This will allow direct access for deliveries. Therefore, there will be doors to go outside allowing access for the deliveries. There also will be interior doors for access by the operators without need to go outside. June 1, 2005 Page 2 of 4 The meeting was then turned over to Todd LaVold, SEH architecturaUeam member, to review the building component view of the water treatment facility. Another packet of drawings was distributed at this I time. These drawings are included as Attachments 3 thru 8. Attachments 3 thru 5 are floor plans for the three levels; lower, mid and upper respectively. Attachment 6 is a sectional view roughly through the center of the building. Attachments 7 and 8 are exterior building elevations. The building has been set up to work with the site and has allowed a split-level arrangement. The upper level includes the meeting and control rooms. In and around the meeting room is an area, which can allow public access to the building. To facilitate this, a unisex restroom has been included in this area. Access control points have been included beyond the pUblic area, which will keep the public out of areas to which they do not need access. Access for staff will be through the lower area in and around the garage, and the locker rooms can be used for their restroom needs. Currently, the building elevations illustrate the use of three building coverings: stone, brick, and metal panel. Todd also handed out site layout drawings. These are Attachments 9 and 10. Attachment 9 shows the site's proximity to Highway 94 at CSAH 2 exit. Attachment 10 shows a closer view of the site. This new site layout differs slightly from what the City has been shown previously. The new site layout has the building oriented directly on a north/south bearing. Previously, the site layouts have had the building parallel with the adjacent frontage road. This would put the building on a roughly northwest/southeast access. Todd discussed his reasoning for pursuing the northlsouth axis rotation. It would allow light to be collected in windows located along the highest level. This would allow for light to penetrate throughout the I building, lessening the amount of artificial light being used. This orientation, along with the ï configuration, aids in hiding undesirabie visual effects, I.e., chemical rooms, garage components, and on- site storage. The east and west elevations illustrate how the ground slopes around the building and how the higher access is in front and lower in back. The lower building level currently does not indicate a service door into the garage area. SEH will include one during design. A discussion was then held on access points to the locker rooms. There was a concern that the operators inside the plant would have to go out into the 9arage area to access the locker rooms. It is intended to have an additional door between the garage and the hallway leading to the locker rooms and meter rooms. The door currently shown was meant as a controlled access point. There is City staff that may have access to the garage but may not have necessarily have access to the water treatment plant. This control point helps keep such people away from chemical feed rooms. SEH will review this more during the design phase. The size of the meeting room is roughly 400 square feet. The City discussed how this would be appropriated for use by all other City staff and not just the water treatment staff. The City requested that SEH look into what would be required to provide audio/visual teaching aides to make this a training room. SEH will follow up on this. The City requested that additional parking spaces be included at the front of the building since the meeting room is being considered for multiple uses. I I I I i June 1, 2005 Page 3 of 4 I I The City asked how the plant would work for expansion. Jeff briefly explained the economics of building in expansion at this time or to make sure our design does not preclude expansion. SEH has taken this I philosophy in mind in setting up the treatment process. The pilot study reviewed filter run times for filters at 2.0 gpm/sf and 3.0 gpm/sf, which directly equates to the plant being set for 2.0 MGD (million gallons per day) and 3.0 MGD. The pilot study shows run tim$s for 2.0 MGD at 40 hours before terminal head loss and 28 hours for 3.0 MGD. This summarizes that the plant, as currently configured, can be expanded to a 3.0 MGD plant without structural modification. Only some internal items will need review for additional well(s) and/or additional pumpage. i During design, SEH will also further review chemical feed needs as to equipment sizing and will evalJate the economy to upsize or not at this time. To expand the plant to the ultimate design being considered, 4.5 MGD building modifications would be required. The current configuration allows for this. Two additional filter bays would be added, probably onto the right side (east) of the building. Additional detention time would require additional detention tank sizing. This would be accomplished on the left-hand side (west) of the building. SEH will keep these I expansions in mind during design and will look into the inclusion of knockout panels in the required areas. i The existing plant will be run until it is no longer feasible to do so. When this happens, an additional 110 MGD loading would be placed onto the new plant. These contingencies will be considered during review of operations of the plants in tandem and when future expansions may need to be required. When the new plant goes on line, the City will be required to chlorinate their water. Currently, the City 'is not chlorinating but has in the past. The City plans to start chlorination next spring to get the customets used to the water being chlorinated. This will also aid in keeping the customers from blaming the new I plant for the change in their water. ! I , Fencing was discussed, and several ideas were kicked around. It was concluded that some sort of I , decorative fencing be reviewed and fit into the building scheme. It was also concluded that the only area needing fencing was the lower parking area, including in front of the garage. Gates and access will be' sized for appropriately sized delivery trucks. The most size-prohibitive vehicle the City would have would be a jetter truck. This would be similar in size to a chemical delivery truck. The fence should not be industrial looking. Site storage will need to include an area for storage of pipes and hydrants. The City asked that SEH follow current design standards to set an example for future commercial expansion within the City. Keeping in mind that an example needs to be set for others, the City asked that SEH look into including the generator inside the WTF structure. There will be treatment setback issues that will be incorporated into the design. The most logical place right now appears to be in or around the garage and locker roöm area. . i i SEH asked if natural gas is available to power the generator. However, other propellant options may be more economical. SEH will evaluate these alternatives and report back to the City. SEH will confirm who would provide electrical service to the plant. The anticipated schedule is to have a 30% set of drawings done by the end of this month. SEH will proceed with soil boring and site surveys based on the layout presented today. Once the 30% set of drawings has been completed, SEH will meet with the MPCA, the governing review agency, to get them in the loop early. SEH will pursue getting MPCA on board and comfortable with the design parameters' At this time, SEH will aiso meet with the City to review progress and discuss direction of the project. June 1, 2005 Page 4 of 4 The ultimate goal is to have a biddable set of drawings completed by September so that the job can be bid and work commenced yet this construction season, weather permitting. Security was discussed. SEH will develop some quotes from area vendors and report their findings to the City. SEH would like an idea of security needs so that electrical requirements for the system can be included in the project. The meeting was adjourned. ~··.~a~ Ju Weyrens PI inistrator I I I