7200 HARDESON RD 2016-01-01 MF Import

C� �� LI-1 .� ' CN,4 Architecture Group 12 April 19� 1 ..� W-7352 Page 3 3.0 SITE HISTORY A brief history of 'he project site is presented in order to understand the nature of soil conditions. This t�istory is based upon past discussions with employees at the gravel pit, a review of aerial photographs, a review of other consultants' work on the praperty, and our previous experience on the site. l�he property was developed as a sand and gravel mining operation at least as long ago as the early 1960s. Previously operated as the Norstar pit, the site supported sand and gravel mining and the aggregate processing associated with the production of concrete, asphalt, and a masonry sand. Excavation in the 1960s and early 1970s produces the high steep western stopes which still exist. The operation primarily utilized advance outwash sand and gravel, wiiich underlies glacial till, a silty graveliy sand. A review of aerial phatographs has shown that several large settling ponds vere utilized over tPie years. These were located at the far southern end of the site, under and to the west of what is now Harde�ison Road and in the northern portion of the site. It is our understanding that Merrill Creek Associates, current owners of the property, bought tha property in 1979. Subsequent to the purchase, Merrill Associates learned of the numerous settlement ponds which had been covered with soil fili. Cascade Geotechnical was retained by the owners in order to perform a subsurface exploration oi the property. Three phases of exploration consisting of borings and test pits were conducted in 1985 and 1986. The explorations disclosed the sediment in several settling ponds and other uncontrolled fill ma�erial. � �1 Merrill Creek Associates initiated rehabilitation efforts in 1986. The majority of the parcel has been graded to an elevation close to that of Hardenson Road. Steep banks L� bordering the site on the v+est have apparently not been graded since the early days of the previous gravel pit operations. Field reports submitted by Cascade Geotechnical described excavation and filling of several areas on the site between 1986 and the present. However, Cascade was present to observe the efforts and to perform in-place densiry tests oniy on an intermittent basis. Precise location of the soft the areas rehabiiitated were not available in the reports. A 1989 summary letter from Cascade to Merrill Creek Associates describes the site work accomplished under their observation. :�.,,;. r:=�•;'�;.... ,_�. .'�: s;�:f;�6$c� . . '','rd �r�' ��'j ` " i . .. .. .. . i�� .:.TA'nR'�F'� . 4j��