2320 RAILWAY AVE INTERWEST CONSTRUCTION INC 2023-02-02

I INTERWEST—EVERETT CONTRACTOR'S YARD SITE IMPROVEMENTS Sitts & Hill Engineers, Inc. IOPERATION AND MAINTENANCE MANUAL Job Number 18,831 I Maintenance Depending on the configuration of the particular system, . P 9 9 , IV maintenance personnel will be required to enter the vault to perform the maintenance. 'I' '�--- -- ' I In" Important:If vault entry is required,OSHA rules for confined j - --� , space entry must be followed. 41 /r % " �,,1 Filter cartridge replacement should occur during dry weather. r" It may be necessary to plug the filter inlet pipe if base flows is occurring i t _ OM ' Replacement cartridges can be delivered to the site or customers 7T., facility.Information concerning how to obtain the replacement — -..�, ;�et.- ' ' cartridges is available from Contech Engineered Solutions. ' _ r Warning:In the case of a spill,the maintenance personnel .i `4.. . • ii.,. should abort maintenance activities until the ro er ;�;: �, 'e P p guidancer . • ., i I is obtained.Notify the local hazard control agency and ` , _" Contech Engineered Solutions immediately. • .} To conduct cartridge replacement and sediment removal . --�--I--- �.I„ 14' - , i . I maintenance: 'r `+ „ 1. If applicable,set up safety equipment to protect maintenance ' ...I�+ •"' r, -rr�_ personnel and pedestrians from site hazards. ' 2. Visually inspect the external condition of the unit and take J I notes concerning defects/problems. 3. Open the doors(access portals)to the vault and allow the E system to vent. -'I - 4. Without entering the vault,give the inside of the unit, Important:Care must be used to avoid damaging the including components,a general condition inspection. cartridges during removal and installation.The cost of 5. Make notes about the external and internal condition of repairing components damaged during maintenance will be the vault.Give particular attention to recording the level of the responsibility of the owner. I sediment build-up on the floor of the vault, in the forebay, Set the used cartridge aside or load onto the hauling and on top of the internal components. truck. 6. Using appropriate equipment offload the replacement cartridges(up to 150 lbs.each)and set aside. D Continue steps a through c until all cartridges have been I 7. Remove used cartridges from the vault using one of the removed, following methods: Method 2: Method 1: A. This activity will require that maintenance personnel enter A. This activity will require that maintenance personnel enter the vault to remove the cartridges from the under drain the vault to remove the cartridges from the under drain manifold and place them under the vault opening for manifold and place them under the vault opening for lifting(removal). Disconnect each filter cartridge from the lifting(removal). Disconnect each filter cartridge from the underdrain corrector by rotating counterclockwise 1/4 of I underdrain connector by rotating counterclockwise 1/4 of a turn. Roll the loose cartridge,on edge,to a convenient a turn Roll the loose cartridge,on edge,to a convenient spot beneath the vault access. spot beneath the vault access. B. Unscrew the cartridge cap t,sing appropriate hoisting equipment,attach a cable C. Remove the cartridge hood and float. I from the boom,crane,or tripod to the loose cartridge. Contact Canted,Engineered Solutions for suggested D. At location under structure access,tip the cartridge on its attachment devices. side. I 3. Remove the used cartridges(up to 250 lbs.each)from the E Empty the cartridge onto the vault floor.Reassemble the vault. empty cartridge. F. Set the empty,used cartridge aside or load onto the hauling truck. I G. Continue steps a through a until all cartridges have been removed. 4 I SITTS& HILL ENGINEERS, INC. 22 ITACOMA, WASHINGTON