Issues regarding the new NPS methodology used to evaluate the achievement of natural quiet restoration standards in Grand Canyon National Park :  oversight hearing before the Subcommittee on National Parks and Public Lands of the Committee on Resources, House of Representatives, One Hundred Sixth Congress, first session, May 25, 1999, Washington, DC. 

 - Washington :  U.S. G.P.O. :  For sale by the U.S. G.P.O., Supt. of Docs., Congressional Sales Office,  1999 [i.e. 2000] 
 - iii, 141 pages :  illustrations, maps ;  23 cm 
<br/><br/> Shipping list no.: 2000-0516-M.  "Serial no. 106-33."  CRDP Program record. 
<br/><br/>Includes bibliographical references. 
<br/><br/><br/>Microfiche. <br/>Washington, D.C. : <br/>U.S. G.P.O., Supt. of Docs., <br/>2000. <br/>2 microfiches : negative. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Airplanes--Noise--Government policy--Arizona--Grand Canyon National Park.<br/>Noise pollution--Government policy--Arizona--Grand Canyon National Park.
<br/><br/><label>Subjects--Geographic Terms: </label><br/>Grand Canyon National Park (Ariz.)
<br/><br/><label>GPO Item No.: </label>1023-B (MF) 
<br/><br/><label>Gov. Doc. Class. No.: </label>Y 4.R 31/3:106-33 
<br/><br/><label>Report. No.: </label>Serial no. 106-33 (United States. Congress. House. Committee on Resources)