Workers began preliminary surveys and testing Monday of the proposed site of a Triumphal Arch sought by President Donald Trump , the latest step in plans for the contentious project in the nation's capital. Workers were seen inspecting the site of the proposed arch between the Lincoln Memorial and Arlington National Cemetery with tools and equipment. Part of the site was fenced off and pink flags typically used as survey markings were planted in the grass. The work on the site was announced in a court filing Thursday in a federal lawsuit challenging the proposed arch. It consists of "surveys and geotechnical testing which are being used to generate information that will assist Defendant National Park Service (NPS) in completing procedural prerequisites” that are part of the decision-making process. The 250-foot-tall (76-meter) proposed arch is one of several projects the Republican president is pursuing to leave his lasting imprint on Washington .…