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�� � . <br /> ^7 -Q[y <br /> 68L <br /> '. <br /> Page 6 " ^,. <br /> The Surface Mining Control and Reclamation Act of 1977 (Public Law 95-87) called <br /> for the establishment of the Office of Surface Mining, Reclamation and Enrorce- 03 <br /> me«t (OSM) within the U. S. Department of the Interior, One responsibility of <br /> this agency was to develop controls over blasting operations at surface coal <br /> Interim Regulatory Program was published in the Federal <br /> Register on December 13" | <br /> mining operations. The �w9// and stated that a particle velocity of l^0 inch <br /> per second shall not be exceeded "at the immediate location of any dwelling, <br /> public building, school , church, or commercial or institutional building." <br /> Since it appeared to us that considerable difficulty would be encountered <br /> in <br /> attempting to justify higher vibration levels, we recommended that most operations <br /> conform to this limit, even though it applied only to surface coal mining. <br /> Jr! May of 1980" the U. S. Court of Appeals for the District tr1ct nf Columbiaoxer- <br /> ::»rneu certain earlier rulings of a lower court which had upheld the OSM Interim i <br /> m <br /> /rugram One provision overturned was 1.0 inch per second limit on particle <br /> velocity; the limit was raised to 2.0 inches per second in accordance with the <br /> ?71 recommendation <br /> of the Bureau Of Mines. <br /> '' other studies have been published or are in the process of being j <br /> ''owcvcr"d which support a limit lower than 2'0 inches per second in many circum- <br /> stances. w continuing to recommend a limit on particle <br /> �tancas^ Accordingly" we are d where the predominant frequency of the ground <br /> motion is less than 40 Hz (cycles per second).��louity of 1.0 inch per second r second) This would apply to almost all <br /> mine and most quarrying nperutions. <br /> In view of the foregoing, our recommendation for a limit on the ground motion <br /> .',aduoed by blasting operations is as follows: <br /> The vibration levels from blasting operations it a quarry, l <br /> as measured on the ground adjacent to the closest residential, <br /> commercial, or industrial structure not on quarry property, <br /> shall not `xceeJ a particle velocity of 1.0 inch per second on <br /> sna cingle�component of motion, longitudinal (horizontal <br /> any single <br /> along the line between the blast and the seismograph <br /> motion transverse (horizontal motion at right angles to <br /> location), ''" The �� <br /> the longitudinal), or vertical. hration intensities <br /> shall be measured with a three-component portable seismograph <br /> oc�ty, in accordance <br /> N1 <br /> yielding a direct recording of particle ve/ " in RI SgGD <br /> with recommendations of the U. S. Bureau of Mines 5968, <br /> Review of Criteria for Estimotin^ Uama"e to Residences from <br /> Blasting Vibrations, and in RI 5487 Design Requirements for <br /> Instrumentation to Record Vibrations Produced by Blasting. <br /> 6�d that:the limits ���ap�ly � ' <br /> In the foregoing cnscussinn" ""~~(' ~�~~^ is the logical h in our <br /> at the nearest non-o«mpanY structure(s).- <br /> tructu"= "). ^ ~rr�ng at these locations <br /> judgment. Our primary concern is what is ."^^, <br /> rather than at other points. <br /> - <br /> ur3l <br /> . . <br /> Page 7 <br /> Tf we have left any questions unanswered, please do not fail to contact us <br /> regarding them. <br /> _ Very truly yours, <br /> PHILIP R. BERGER & ASSOCIATES, INC. <br /> Philip R. Berger <br /> President <br /> PRB/eb <br />