美國內政部長柯偉德(Dirk Kempthorne)於12月16日參加為內政部第三大樓的綠化環保屋頂所舉行的剪綵儀式。
「還有什麼地方比華盛頓特區的保育部門更適合安裝綠化環保屋頂呢？」柯偉德表示，「一半以上的華盛頓特區都被鋪滿了不透水的表面，所以水無法滲入地面，造成了75%的雨水逕流，」他表示，在綠化環保屋頂上的植披和泥土可以吸收雨水，防止雨水造成的逕流情況。
華盛頓特區向來有豪雨逕流和地下污水溢流的問題，每一年至少有10億加侖的污水排入波多馬克河(Potomac River)、安那考斯迪亞河(Anacostia River)和石溪(Rock Creek)，這三條河都是流入脆弱的乞沙比克灣(Chesapeake Bay)流域的支流。
內政部的綠化屋頂可以幫助減輕這個問題，這個屋頂可以吸收7/10英吋的降雨，減少豪雨逕流流入地下水系統。
這個環保屋頂也可以中和酸雨、過濾從雨水和雪水中的污染物以改善水質，同時為鳥類和傳粉昆蟲提供安身之處。屋頂的植物也可以有遮蓋日光直射的效果，延長屋頂的壽命，在夏天時提供隔絕熱源的效果，減少都市熱島效應。
在建築物裡面，他還可以減少由外界傳來的噪音，對員工和訪客來說也能提供賞心悅目的景色。
最後，這個綠化環保屋頂還可以改善一點城市裡的空氣品質，光和作用可以將二氧化碳轉為氧氣。
綠化屋頂的計畫在7年前開始，當國家商業中心設施管理服務部的主管賽爾(Mike Cyr)讀到一篇歐洲的綠化屋頂的文章，即使當時綠化屋頂並不普及，但是賽爾還是決定嘗試在內政部裡面安裝綠化屋頂。
國家商業中心的員工與內部的技術環保政策專家合作，這個團隊由接受由國家可再生能源實驗室提供的免費技術支援開始。
可行性評估證實了內政部的綠化屋頂，在一定的限制是可行的。在招商和簽訂合約的過程中，他們同時也和美國環保署和服務管理處合作，最後的屋頂是由費城的Roofscapes公司所安裝，這家公司曾因在芝加哥市政廳安裝的綠化屋頂而獲獎。
綠化屋頂是內政部建築翻新計畫的一部份，翻新會以六個階段來實施，每個階段翻新六個大樓的其中一棟，計畫會於2011完成，花費約1億7500萬美元。
Secretary of the Interior Dirk Kempthorne today cut the ribbon opening a new green roof that has been planted on the third wing of the Main Interior Building in Washington.
"What more suitable place for a green roof than the headquarters of America's conservation department in Washington, DC?" Secretary Kempthorne asked.
"With more than half of Washington, DC covered with paved or constructed surfaces that do not allow water to infiltrate the ground, 75 percent of rainfall becomes runoff," he said. The vegetation and soil on the green roof will absorb rainwater and curb runoff.
Washington, DC has a enormous problem from stormwater runoff and sewer overflows. Each year, at least a billion gallons of raw sewage are discharged into the Potomac River, Anacostia River and Rock Creek - all tributaries of the fragile Chesapeake Bay watershed.
The green roof on the Main Interior Building will help ease this problem by holding up to seven-tenths of an inch of rainfall to reduce stormwater runoff entering the sewage system.
The green roof also will improve water quality by neutralizing the effects of acid rain and filtering pollution from rain and snow. And it provides habitat for songbirds and pollinators.
The plants will shield the roof from the Sun's direct rays, which extends the roof's life span, insulates the building during the summer and saves energy as well as mitigates urban heat island effects.
Inside the building, it will reduce noise transfer from the outdoors and provide a visually attractive sight for employees and visitors.
Finally, the green roof is expected to improve the city's air quality a little by filtering the air that moves across the plants and, through photosynthesis, convert carbon dioxide into oxygen.
The green roof project started more than seven years ago when Mike Cyr, the National Business Center's chief of the Division of Facilities Management Services, read an article on the benefits of green roofs in Europe. Although green roofs were not commonplace at the time, Cyr decided to explore the possibility of installing a green roof on the Main Interior Building.
National Business Center personnel worked with in-house technical experts in the Office of Environmental Policy and Compliance. The group started by applying for and receiving free technical assistance from the Department of Energy's Federal Energy Management Program via the National Renewable Energy Laboratory.
The feasibility study confirmed a green roof would work on the Main Interior Building within specified limitations.
They also partnered with the U.S. Environmental Protection Agency and the General Services Administration to work through the contracting process to find a green roofing company. The roof was installed by Roofscapes, Inc. of Phildelphia, the award-winning company that installed the famous green roof on Chicago City Hall.
The green roof is part of an ongoing modernization of the Main Interior Building will be conducted in six phases. Each phase will correspond to one of the six wings of the building, with a scheduled completion date of 2011 at an estimated cost of $175 million.
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In my healing journey and learning to attain the breath awareness, I become aware of the reality that all the creatures of the world are breathing the same breath. Take action, here and now. From my physical being to the every corner of this out of balance's planet.
