Sole Source - Lakeside Vessel Barrier Gate Repair at Hoover Dam This is being advertised as a noncompetitive Sole Source Solicitation. However, any responsible source may submit a response which will ... Sole Source - Lakeside Vessel Barrier Gate Repair at Hoover Dam This is being advertised as a noncompetitive Sole Source Solicitation. However, any responsible source may submit a response which will be considered and reviewed by this agency, if received in a timely manner. The North American Industry Classification System (NAICS) Code for this acquisition is: 237990 Other Heavy and Civil Engineering Construction. The small business size standard for NAICS 562111 is $45.0 Million.