9931 19TH AVE SE 2018-01-02 MF Import

ENVIRONMENTAL ASSOCIATES, INC. 2122 - 1121h Avenue North East, Suite B-100 Bellevue, Washington 9M (XM) 399-"l (206) 455-9025 FAX: (206) 455-2316 April 10, 1997 Mr. Al Kendall Barghausen Consulting Engineers 18215 72nd Avenue South Kent, Washington 98032 (Fax: 206-251-8782) Subject: RESPONSE TO COMMENTS OF CITY OF EMETT Aspects Relating To Proposed Keystone Mall Proposed Arco AN/PH Nini-Market NEC 300th St. S.E. at Hwy. 527 Everett, Washington Dear Mr. Kendall: JN 6413 X In response to your request, our technical team has reviewed the comments written on the plans by City of Everett reviewer which you provided. Responses in a form suitable for submission to the agency are enclosed. I apologize for the delay in getting this out to you as I was in an unavoidable continuing education program at the end of last week for my professional licensure in the State of Illinois. From the telecons I received, it is my understanding that my secretary conveyed that detail to you, and that this is satisfactory. The well-intentioned questions posed by the plan reviewer were simple: (1) They wanted some confirmation that the 3 foot high proposed wall will stand even though 1.6 feet of water may occasionally rise along its south face, and; (2) They requested a comment to the effect that the wall design is "essentially impermeable" to the extent that the pond will not "drain out through the keystones". As outlined in the attached letter, the "integrity" of the proposed very low (3-foot high) keystone wall in terms of longevity and minimal maintenance is dependent primarily upon the factors including (1) support or bearing, (2) minimal lateral soil pressures, and parenthetically; (3) reduction/elilnination of hydrostatic forces behind the wall. Although not focused specifically upon a keystone design, you may recall that each of these design issues was addressed in some detail in our — Associate Offices: Oregon / San Francisco Bay Area