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HomeMy WebLinkAboutCAG1997-0133 - Supplement - King County Dept of Natural Resources - Provision of Surface Water Services - 07/10/2011 Additional Services Interlocal Agreement Between King County and City of Kent For The Provision of Surface Water Services Scope of Work 2011 Citywide Stormwater Pond Maintenance King County will provide services to the City of Kent under this Scope of Work pursuant to the Interlocal Agreement Between King County and the City of Kent for the Provision of Surface Water Services, executed March 26, 1997. PROJECT DESCRIPTION The project consists of removing approximately 12,000 tons of combined soil sediments and vegetation growth from 47 identified City owned stormwater ponds. This work will help restore the overall stormwater runoff holding capacity of the ponds that have diminished over the years with sediment and vegetation build-up. This work will also include miscellaneous items and other related work associated with the maintenance of the stormwater ponds. The purpose of this project is to perform work identified as a maintenance component within the City's National Pollutant Discharge Elimination System Phase 11 Permit. The NPDES Phase Il Permit requirements state that after a deficiency is found within city owned stormwater ponds that the City has 24 months from the date of inspection to make the necessary repairs. TASKS City of Kent has developed special provisions and construction plans for the project titled 2011 Citywide Stormwater Pond Maintenance dated May 12, 2011, which provides a detailed description of all required tasks and is attached as Exhibit A. The following is a summary of key tasks: A. Temporary Erosion and Sediment Control 1. The following tools and materials will be available on site and deployed as needed during construction: • Straw bales for slope mulching • Silt fencing for perimeter siltation control • Hand brooms, street sweepers, and wash trucks for control of sediments on paved traffic surfaces • A spill response kit All paved traffic areas will be kept free from sediment accumulations by daily sweeping or washing. B. Traffic Control 1. Maintain all traffic with traffic control flaggers throughout construction activities. Additional Work. Interlocal Agreement 1 King County and City of Kent Surface Water Services ,tea I C. Miscellaneous Maintenance 1. Perform mowing and selected removal of trees and tree stumps that exceed 18 inch diameter Place riprap around conveyance lines that inlet into the pond as stated within the specifications provided. Place crushed rock surfacing as directed by City staff. 2. Remove and restore fencing as shown on site drawings,the specifications and or by the City representative. D. Removal and Disposal of Material 1. Remove and properly dispose of solids and sediments within the 47 listed stormwater ponds The estimated quantity of soil sediments and vegetation to be removed is 12,000 tons. 2. Hydroseed the exposed soil areas that have been impacted by the maintenance activity as stated within the specification package and shown within construction plans or as directed by the City representative. SCHEDULE Work is anticipated to be completed within 60 working days after a notice to proceed is issued,and no later than September 30, 2011 unless otherwise allowed in writing by the City representative . Hours of construction between 7:00 am and 10 pm. ESTIMATED COST The project work is currently estimated to not exceed $780,000, which includes sales tax and some contingency to account for unexpected costs that may occur during the maintenance activity. As provided in Exhibit B, the county has provided an estimate of $618,296.51 to perform the work. This cost, however, does not include sales tax and does not include any measure of contingency if unexpected site conditions are encountered which could impact the overall costs. The County will provide the City all invoices and costs incurred for construction costs. If any change order is needed,the County will immediately inform the City in writing of the proposed changes and the change order work shall not proceed until the City has approved The amount of any change orders shall not cause the total costs for the project work to exceed the above estimate. Authorized by City of Kent: Name: Suzette Cooke Ti • M r ate: `7 6 Additional Work: Interlocal Agreement 2 King County and City of Kent Surface Water Services ® REQUEST FOR MAYOR'S SIGNATURE KENT Please Fill in All Applicable Boxes NAPS H 11.GT0 N Routing Information (ALL REQUESTS MUST FIRST BE ROUTED THROUGH THE LAW DEPARTMENT) Originator if b/C( ey- V Phone (Originator)• 55 zg Date Sent 7 s.- l Date Required 7 J � Retuin Signed Document to ���,� uf� 6 CONTRACTTERMINATI0N DATE: l� VENDOR NAME: CtVn-(t'1 D-kV4 OC-qtj DATE OF COUNCIL APPROVAL: `f/ Brief Explanation of Document• 5*0vi w Q 66vylt) - s�44e�JocQ( All Contracts Must Be Routed Through the Law Department •This Aiea to be Completed By the Law Department) Received: RECEIVED C/�e ` ,c Appioval of Law Dept. �lL�l.��� V G® eft Law Dept Comments. JUL d 6 2011 KENT LAW DEPT. Date Foi�varcled to Mayor- Shaded Areas to Be Completed by Administration Staff Received- Recommendations & Comments: Disposition �� ' YV12__ r F � Date Returned: ` s� otKEh7 Cl a e5f3,-0 3 05