Italian industrial group ASTM has been awarded an important tunnelling contract in the USA. I read this in their site.

ASTM Group Is Awarded A New Contract In The USA: It Will Build A Tunnel Under The Potomac River,
An Important Environmental Project For Washington D.C.

• The new tunnel is part of the broader Clean Rivers Project program launched by DC Water: an imposing $2.6 billion environmental plan to re-establish the quality of the water in the Potomac River.
• The project, for a total contract value of $819 million, will be carried out by Halmar International in partnership with CBNA, a subsidiary of Bouygues Construction.

Tortona, 23rd November 2023. The ASTM Group, second largest motorway concession operator in the world and a leader in the realization of large works and in mobility technology, has been awarded, through its subsidiary Halmar International, the contract for the design and construction of a tunnel under the Potomac River. This is the largest project ever awarded by DC Water, the District of Columbia water authority that provides drinking water, wastewater collection and treatment services to the US capital.

The project — worth a total of $819 million — was assigned to the joint venture made up of CBNA (70%), a
subsidiary of Bouygues Construction, and Halmar (30%). The project consists of building a 5.5-mile-long (8,840m) tunnel with an internal diameter of 18 feet (5.50 m), excavated to an average depth of 100 feet (30 m) in variable geological contexts and near capital city landmarks. The project also includes a series of diversion structures, collection pits and support structures to capture flows from existing mixed sewer overflows along the Potomac River and ultimately convey them to the Blue Plains wastewater treatment plant.

The main tunnel will be executed by mechanized excavation, which will require the use of two TBMs (Tunnel Boring Machines) specially customized to the different geological conditions expected along the route.

This is the final phase of the broader Clean Rivers Project program launched by DC Water, an impressive $2.6 billion plan which will enable the implementation of combined sewer overflows (CSOs) to help the US capital to prevent overflowing of drainage and sewerage infrastructure, particularly during heavy rainfall, thus protecting the biodiversity of the Potomac River, the fourth largest river along the of the United States East Coast.

Construction is estimated to last for about 6 years.

In the United States, through Halmar, the ASTM Group recently completed the projects for the Long Island
Railroad Third Track Expansion ($1.83 billion) and the Potomac Yard subway station of the Washington
Metropolitan Area Transit Authority ($264 million).

As of today, the Group is also working to complete the following projects:
- design and build Penn Station in the New York subway ($1.85 billion

- improve the accessibility of 13 New York Metropolitan Transportation Authority stations 1 ($450 million)
- replace the Park Avenue viaduct by the Metro-North Railroad, Phase 1 ($383 million)
- renovate some areas of JFK airport (a project worth $1.24 billion).

https://www.astm.it/wp-content/uploads/2023/11/23.11.2023_ASTM_PotomacRiverTunnel_ENG.pdf