Indefinite delivery-indefinite quantity contract for aid-to-navigation (ATON) structure replacement at SAN francisco, SAN pablo, suisun BAY, sacramento and SAN joaquin river, california

The purpose of this amendment is to:
A. Extend the due date for bid submission
B. Provide responses to questions from prospective bidders
C. Revise Section B (Schedule of Prices)
D. Revise paragraph M.2 of the solicitation
E.  Change the header information

The purpose of this contract solicitation is to award a Indefinite Delivery, Indefinite Quantity Contract for Aid-To-Navigation (ATON) Structure Replacement for the following geographic Areas: Geographic Area Number I- All ATON structures located in San Francisco Bay and waters that connect to San Francisco Bay within the bounds of the Golden Gate Bridge, San Francisco South Channel Daybeacon 20, and East Brothers Island Light; Geographic Area Number II - All ATON structures located in San Pablo and Suisun Bays and waterways that connect to San Pablo and Suisun Bays from north of East Brothers Island Light to Winter Island; Geographic Area Number III - All ATON structures located in Sacramento and San Joaquin Rivers and waterways that connect to them, including Deep Water Ship Channels, up to Sacramento and Stockton, respectively. (Sacramento River Light 86 and Stockton Channel Light 48 mark the upper boundary of aids covered under this contract). Work includes: (1) Standard ATON Maintenance work which includes removals, replacements, and repairs of damaged ATON structures;(2)ATON parts fabrication;(3)Emergency ATON Maintenance work which includes emergency removal of damaged ATON structures that present a hazard to navigation; (4) Geodetic survey and reporting work with a minimum accuracy level of third order, class I, conducted by a Professional Land Surveyor; (5)Diving to reclaim knock-down structures and retrieve any lost batteries. Diving may also be performed to survey the underwater condition of ATON structures. The maintenance work for this contract will be executed through task orders provided to the contractor by the Contracting Officer. The task orders will provide scopes of work for each individual ATON structure that requires maintenance. Task Orders will range from $100,000 to $500,000.  The Government contemplates awarding a contract for a base year with four option years.