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| | Washingtons Magnificent Metro - Railway Age, September 2001 |
 | | In the downtown Washington area underlain by an ancient seabed, most of the tunneling was in soft ground, while hard rock was encountered in the northern end of the District and in Montgomery County, Md. In the area between, extremely difficult weathered-rock-tunneling prevailed. |
 | | Most of the Metro systems elevated structures were built as cast-in-place, post-tensioned concrete structures, but for its most recent Green Line extension to Branch Avenue, WMATA shifted to the use of precast, post-tensioned segmental girder construction. |
 | | It was a festive occasion last Jan. 13 when the Washington Metropolitan Area Transit Authority (WMATA) celebrated the opening of a Metrorail Green Line extension to Branch Avenue in suburban Prince Georges County, Md., that completed the final leg of a 103-mile, 83-station rail system plan for the national capital region adopted in 1969. |
| www.railwayage.com /sept01/washmetro.html (2151 words) |
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