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HomeMy WebLinkAboutLUA00-098 CITE )F' RENTON Hearing Examiner Jesse Tanner,Mayor Fred J.Kaufman • October 31,2000 Nicola Robinson 3110 SE 5th - R3enton WE, 98058-2824 • Re: . APPEAL OF DNS-M FOR SUNNYDALE STORM SYSTEM REPLACEMENT FILE Na LUA00-098,AAD Dear Ms.Robinson: The Examiner's Report and Decision on the above referenced matter,which was issued on October 16, 2000,was not appealed within the;14-day period established by ordinance. Therefore,this matter is considered fmal by this office and the file on your;appeal'is being transmitted to rthe City Clerk as of this date. • Please feel free to contact this;office if further assistance or information is required. Sincerely, Fred J.Kaufin Hearing Examiner: FJK/jt cc: Leslie Nishihira Sandi Seeger,Development Services • • 1055 South Grady Way -Renton,;Washington 98055.-..(425)430-6515. This paper contains 50%.recycled material.20%post consumer --- AFFIDAVIT OF SERVICE BY MAILING STATE OF WASHINGTON ) ss. County of King ) JOAN THOMPSON , being first duly sworn, upon oath, deposes and states: That on the 16th day of October ,2000, affiant deposited in the mail of the United States a sealed envelope(s) containing a decision or recommendation with postage prepaid, addressed to the parties of record in the below entitled application or petition. Signature: SUBSCRIBED AND SWORN to before me this I (s day of _rJ '�`e�- -f P-u0 `-"`"\'\\ __A ND. cp1, N Public . and f r the State of Wa"sl i;,:' 10 , residing at ,therein. ; = .' .s '"oit s ,,,,,.' ,, p - Application, Petition, or Case No.: Sunnydale Storm System Replacethc l p�yASwsAG� LUA00-098.AAD `� The Decision or Recommendation contains a complete list of the Parties of Record HEARING EXAMINER'S REPORT October 16,2000 OFFICE OF THE HEARING EXAMINER CITY OF RENTON REPORT AND DECISION APPELLANT: Nicola Robinson Appeal of DNS-M for Sunnydale Storm System Replacement File No.: LUA00-098,AAD LOCATION: SW of Sunnydale Mobile Home Park,North of SE 5th SUMMARY OF APPEAL: Appeals DNS-M and requests further study of the impact to existing stream and wetland PUBLIC HEARING: After reviewing the Appellant's written request for a hearing and examining the available information on file,the Examiner conducted a public hearing on the subject as follows: MINUTES The following minutes are a summary of the August 29,2000 hearing. The official record is recorded on tape. The hearing opened on Tuesday,August 29,2000,at 9:00 a.m. in the Council Chambers on the seventh floor of the Renton City Hall. Parties wishing to testify were affirmed by the Examiner. The following exhibits were entered into the record: Exhibit No. 1: Yellow file containing the appeal, Exhibit No.2: Exhibit No.2: Yellow file No. proof of posting and publication, and other LUA00-071,ECF containing the original application, documentation pertinent to the appeal. proof of posting,proof of publication and other documentation pertinent to this request(by reference) Exhibit No.3: Ms. Robinson's written comments Exhibit No. 4: Declaration of Allen Quynn Exhibit No. 5: Site map(A&B) Exhibit No. 6: Vicinity map Parties present: Nicola Robinson, appellant 3110 SE 5th Renton, WA 98058-2824 Representing City of Renton Russ Wilson,City Attorney Leslie Nishihira,Development Services Allen Quynn 1055 S Grady Way Renton, WA 98055 Nicola Robinson Appeal of DNS-M for Sunnydale Storm System Replacement File No.: LUA00-098,AAD October 16,2000 Page 2 The Examiner explained that the appeal was an administrative appeal held pursuant to Ordinance 3071 and was the only administrative review to occur on the matter. The matter may be submitted back to the Examiner for reconsideration if the parties are not satisfied with the decision. He stated that the appellant had the burden of demonstrating that the City's action was erroneous, and would have to show clear and convincing evidence that the City's determination was incorrect. At that point the City could respond, if they chose to do so. As a preliminary matter,the City Attorney moved to have the appeal dismissed for lack of standing on the appellant's part, and stated the appellant failed to allege any specific harm that the replacement system would cause. The Examiner overruled the motion and allowed the appeal to go forward. Ms.Robinson stated that a matter of concern was the wetland located to the north of a stream which runs parallel to the existing pipe. In the past 10 years there has been flooding of the stream. With the increased flow from the new pipe,there may be increased flooding and potential degradation of the wetland. She also stated the latter portion of the pipe cuts across a path which the neighborhood has been using for several years. A further concern was the release of sedimentation into the stream and potentially the wetland. It was her understanding that the Sunnydale treatment facility was not up to the current standards. She also stated that wildlife habitat was not addressed in the SEPA review. Even though the City is not in a position to treat the existing stream in any other way than a conveyance of storm water, Ms. Robinson was concerned when a project is passed without considering the natural environment. She would like to see the pipe moved to another location that would not impact this stream and wetland in the way proposed. She referred to Department of Ecology's storm water manual that states "streams are not to be used as a means of conveyance for storm water run-off." Mr. Wilson stated that the vested rights doctrine applies to these types of projects and their SEPA review. The system does not have to meet current codes,but only those that were in place at the time it was installed. The record must demonstrate that environmental factors were adequately considered in a manner sufficient to establish prima facie compliance with SEPA. The City studied all codes involved, and a geotech study was also completed on the project. The pipe has been leaking for a number of years, but the system's volume is not increasing from when it was originally installed. Ms.Nishihira testified that the new pipeline course was designed to avoid a stream crossing and was determined to be less of an impact to existing slopes. Mr. Quynn explained the current stream and pipeline course, and the proposed pipeline course. The proposal is not a maintenance project,but in fact the pipe is going to be realigned approximately 100 feet south of its location to avoid impacts to the stream. The flow from the pipe was analyzed using the 25 and 100 year storms, and the pipe was sized to handle the capacity. He described the dissipator at the end of the pipe and its purpose. He further described the actual layout of the pipe and the proposed method of installation. Mr. Quynn clarified that the City used the standards set forth in the King County Storm Water Management Manual. On cross-examination,Mr. Quynn responded that the existing pond at the mobile home park was used only by the mobile home park. Nicola Robinson - Appeal of DNS-M for Sunnydale Storm System Replacement File No.: LUA00-098,AAD October 16, 2000 Page 3 In her closing argument,Ms.Robinson reiterated the Puget Sound Basin's standard that using streams and wetlands as a conveyance of storm water is prohibited under state and federal law. The SEPA review indicates no measures are necessary to decrease aesthetic impacts,but if you live in the neighborhood and enjoy walks in the area,the proposal is considered unsightly. Mr. Wilson concluded that the appellant's case was based on wanting the pipeline moved out of her backyard, and not whether the ERC had done a thorough review. The ERC did in fact review the project and the proposal actually lessened the impact to the environment. The Examiner called for further testimony regarding this appeal. There was no one else wishing to speak. The hearing closed at 10:05 a.m. FINDINGS,CONCLUSIONS &DECISION Having reviewed the record in this matter,the Examiner now makes and enters the following: FINDINGS: 1. The appellant,Nicola Robinson,filed an appeal of a Determination of Non-Significance-Mitigated (DNS-M) issued for a proposed replacement of the Sunnydale Storm System. 2. The City, in the course of, and as a result of its SEPA review, issued a Declaration or Determination of Non-Significance for the project. The Declaration of Non-Significance(DNS)was conditioned by the City in what is known as a mitigation process, and became a DNS-M,the "M" alerting readers to the fact that mitigating measures were attached to the project. 3. The condition imposed by the ERC required compliance with the recommendations found the Geotechnical Report prepared for the project. 4. The appeal was filed in a timely manner. The appellant lives in the Maplewood Community. That community is near the pipeline and the creek it empties into. The appellant apparently walks along a trail that the new pipeline will transect. 5. The action is a City-sponsored action to replace a damaged storm water line. That line drops down from the plateau north of Maple Valley near the Sunnydale Mobile Home near Union Avenue NE and NE 2nd and terminates near SE 5th Street near the Maplewood community. The existing line serves the mobile home park. From the record it appears that the original line was constructed sometime after 1985 or 1986. 6. The appellant's letter of appeal raised issues regarding the affects of the reconstruction on a stream and wetland and wildlife in the Resource Conservation area in which the pipe would be located. Also the appellant raises the fact that the Sunnydale Trailer Park's treatment facility and detention pond do not meet current treatment or water quality guidelines, are undersized and that beneficial uses are impaired and threatened by these issues. The appellant also noted that neither the creek nor the wetland are Nicola Robinson - Appeal of DNS-M for Sunnydale Storm System Replacement File No.: LUA00-098,AAD October 16, 2000 Page 4 properly inventoried and may have been overlooked by the ERC in its environmental review. She also noted that streams are not to be used as a means of conveyance for storm water run-off. The appellant also noted that the current pipe is damaged and probably does not carry the "normal" quantity water and pollutants down to the creek but once repaired,water and pollutant load will be increased. 7. While the project has been termed a"replacement" of a damaged stormwater drainage pipe,the pipe will be relocated outside of the existing alignment in some locations. The record reveals that the reconstructed line will diverge from the current alignment and realigned approximately 100 feet south of its current location. This new alignment was meant to avoid impacts to the stream and to avoid crossing the stream and to lessen the impacts on the steeper slopes. There will be a dissipator at the end of the pipe. The dissipator will be flush with the ground and not be the "typical" above ground birdcage. There will be approximately 150 feet of excavation for the new alignment. Rockery supporting structures will be rebuilt. Some existing access manholes and the damaged pipe will be removed manually to lessen impacts on the slope and vegetation. 8. The appellant noted that the creek has flooded a number of times over the last ten years. The appellant speculates that repairing the pipe so that it conveys all of the stormwater will probably direct more storm water into the pipe and worsen flooding conditions. 9. The appellant seeks either a fuller environmental review or a relocation of the pipe to avoid creating impacts on the stream and wetland. 10. The new 18" (eighteen inch)pipe will cross an existing social trail and probably create an impasse to walking on the trail. 11. The pipeline traverses slopes that range up to near vertical. CONCLUSIONS: 1. The decision of the governmental agency acting as the responsible official is entitled to substantial weight. Therefore,the determination of the Environmental Review Committee(ERC),the city's responsible official, is entitled to be maintained unless the appellant clearly demonstrates that the determination was in error. 2. The Determination of Non-Significance in this case is entitled to substantial weight and will not be reversed or modified unless it can be found that the decision is "clearly erroneous." (Hayden v.Port Townsend, 93 Wn 2nd 870, 880; 1980). The court in citing Norway Hill Preservation and Protection Association v. King County Council, 87 Wn 2d 267, 274; 1976, stated: "A finding is'clearly erroneous' when although there is evidence to support it,the reviewing court on the entire evidence is left with the definite and firm conviction that a mistake has been committed." Therefore,the determination of the ERC will not be modified or reversed if it can meet the above test. For reasons enumerated below,the decision of the ERC is modified. Nicola Robinson Appeal of DNS-M for Sunnydale Storm System Replacement File No.: LUA00-098,AAD October 16, 2000 Page 5 3. The clearly erroneous test has generally been applied when an action results in a DNS since the test is less demanding on the appellant. The reason is that SEPA requires a thorough examination of the environmental consequences of an action. The courts have,therefore,made it easier to reverse a DNS. A second test,the "arbitrary and capricious"test is generally applied when a determination of significance(DS) is issued. In this second test an appellant would have to show that the decision clearly flies in the face of reason since a DS is more protective of the environment since it results in the preparation of a full disclosure document, an Environmental Impact Statement. 4. An action is determined to have a significant adverse impact on the quality of the environment if more than a moderate impact on the quality of the environment is a reasonable probability. (Norway, at 278). Since the Court spoke in Norway, WAC 197-11-794 has been adopted, it defines "significant" as follows: Significant. (1) "Significant" as used in SEPA means a reasonable likelihood of more than a moderate adverse impact on environmental quality. (2) Significance involves context and intensity ...Intensity depends on the magnitude and duration of an impact.... The severity of the impact should be weighed along with the likelihood of its occurrence. An impact may be significant if its chance of occurrence is not great, but the resulting environmental impact would be severe if it occurred. 5. Also redefined since the Norway decision was the term "probable." Probable. "Probable"means likely or reasonably likely to occur, ...Probable is used to distinguish likely impacts from those that merely have a possibility of occurring,but are remote or speculative. (WAC 197-11-782). 6. Impacts also include reasonably related and foreseeable direct and indirect impacts including short- term and long-term effects. (WAC 197-11-060(4)(c)). Impacts include those effects resulting from growth caused by a proposal, as well as the likelihood that the present proposal will serve as precedent for future actions. (WAC 197-11-060(4)(d)). 7. Environmental impact is also related to the location. A development whether an office building or a single family development may or may not create impact depending on the existing surroundings. 8. In the main,the proposal replaces a damaged storm water pipe that already serves the same detention system and empties into the same creek drainage system. While there will be realignment the impacts of the entire project do not appear such that it will have more than a moderate impact on the environment. The new alignment avoids some of the steeper slopes and avoids an unnecessary crossing of the creek. The new dissipator structure will be less visually intrusive. Twenty-five and 100-year storm calculations have been factored into the project. 9. The only cause for concern is that the new pipe will create an approximately eighteen inch(18")barrier to an existing trail that allows residents to enjoy the creek,wetlands and forest environment. The Nicola Robinson Appeal of DNS-M for Sunnydale Storm System Replacement File No.: LUA00-098,AAD October 16, 2000 Page 6 barrier appears to deserve mitigation and the applicant shall provide a method that allows pedestrians to cross over the pipeline and continue to use the existing trail. 10. The determination of the Environmental Review Committee is modified to add an additional mitigation measure. DECISION: The decision of the Environmental Review Committee is modified to contain an additional mitigation measure: 1. The applicant shall provide a method that allows pedestrians to cross over the pipeline and continue to use the existing trail. ORDERED THIS 16th day of October, 2000. FRED J. KAU TAN HEARING E R TRANSMITTED THIS 16th day of October, 2000 to the parties of record: Nicola Robinson Russell Wilson Leslie Nishihira 3110 SE 5th 1055 S Grady Way 1055 S Grady Way Renton, WA 98058-2824 Renton, WA 98055 Renton, WA 98055 Allen Quynn John C. Ramsey Neal Whitney 1055SGradyWay 3517SE5th 3532SE5th Renton, WA 98055 Renton, WA 98058 Renton, WA 98058 James 3324 SE 5th Renton, WA 98058 Nicola Robinson - Appeal of DNS-M for Sunnydale Storm System Replacement File No.: LUA00-098,AAD October 16, 2000 Page 7 TRANSMITTED THIS 16th of October, 2000 to the following: Mayor Jesse Tanner Gregg Zimmerman,Plan/Bldg/PW Admin. Members, Renton Planning Commission Jana Hanson,Development Services Director Chuck Duffy,Fire Marshal Lawrence J. Warren, City Attorney Transportation Systems Division Jay Covington, Chief Administrative Officer Utilities System Division Councilperson Kathy Keolker-Wheeler Sue Carlson,Econ. Dev. Administrator Betty Nokes,Economic Development Director South County Journal Larry Meckling,Building Official Pursuant to Title IV, Chapter 8, Section 15 of the City's Code, request for reconsideration must be filed in writing on or before 5:00 p.m.,October 30,2000. Any aggrieved person feeling that the decision of the Examiner is ambiguous or based on erroneous procedure, errors of law or fact, error in judgment, or the discovery of new evidence which could not be reasonably available at the prior hearing may make a written request for a review by the Examiner within fourteen(14)days from the date of the Examiner's decision. This request shall set forth the specific ambiguities or errors discovered by such appellant, and the Examiner may, after review of the record,take further action as he deems proper. An appeal to the City Council is governed by Title IV, Chapter 8, Section 16,which requires that such appeal be filed with the City Clerk, accompanying a filing fee of$75.00 and meeting other specified requirements. Copies of this ordinance are available for inspection or purchase in the Finance Department, first floor of City Hall. If the Examiner's Recommendation or Decision contains the requirement for Restrictive Covenants,the executed Covenants will be required prior to approval by City Council or final processing of the file. You may contact this office for information on formatting covenants. The Appearance of Fairness Doctrine provides that no ex parte(private one-on-one)communications may occur concerning pending land use decisions. This means that parties to a land use decision may not communicate in private with any decision-maker concerning the proposal. Decision-makers in the land use process include both the Hearing Examiner and members of the City Council. All communications concerning the proposal must be made in public. This public communication permits all interested parties to know the contents of the communication and would allow them to openly rebut the evidence. Any violation of this doctrine would result in the invalidation of the request by the Court. The Doctrine applies not only to the initial public hearing but to all Requests for Reconsideration as well as Appeals to the City Council. CITY OF RENTON OFFICE OF THE HEARING EXAMINER 1N THE MATTER OF THE APPEAL ) OF A DNS-M FOR SUNNYDALE STORM SYSTEM ) DECLARATION OF REPLACEMENT-FILE NO LUA-00-098, AAD ) ALLEN QUYNN ) ) ) Allen Quynn hereby declares under penalty of perjury, pursuant to the laws of the State of Washington that the following is true and correct: 1. I am a civil engineer for the City of Renton. 2. I graduated from the University of Washington with a Bachelor of Science degree in oceanography in June of 1987. 3. I graduated from Washington State University with a Bachelor of Science degree-in Civil Engineering in December of 1993. 4. I am currently the service water utility projects manager for the City of Renton. 5. I am in charge of the project commonly known as the sunnydale storm system replacement project, file#LUA-00-098, AAD. 6. Attached hereto as exhibit A is a true and correct copy of the Master Application submitted to the Environmental Review Committee for the sunnydale project. 7. Attached hereto as exhibit B is a true and correct copy of the environmental checklist submitted to the Environmental Review Committee for the sunnydale project. Attached to that checklist is a true and correct copy of the geotechnical report referred to in the committee's mitigation requirement's. 8. Attached hereto as exhibit C is a true and correct copy of the project narrative submitted to the Environmental Review Committee for the sunnydale project. 9. These are the documents relied upon by the City of Renton in there request for a determination of non-significance. 10. This request was made pursuant to the requirements of RCW 43.21C.030(2)(c). 11. Attached hereto as exhibit D is a true and correct copy of portions of the King County Washington Surface Water design Manual. 12. This manual is the controlling authority for the sunnydale project. 13. Attached hereto as exhibit E is a true and correct copy of the definition of an impervious surface as defined by the stormwater management manual for the puget sound basin. 14. The sunnydale project does not involve the installation of any impervious surfaces. 15. The sunnydale project does not require the installation of any filtration system. 16 Attached hereto as exhibit F is a true and correct copy of determination of non significance-mitigated issued by the Environmental Review Committee. Dated this 28th day of August, 2000. aakv, Allen Quynn AFFIDAVIT OF PUBLICATION Charlotte Ann Kassens, first duly sworn or. oath states that he/she is the Legal Clerk of the SOUTH COUNTY JOURNAL 600 S. Washington Avenue, Kent, Washington 98032 a daily newspaper published seven (7)times a week. Said newspaper is a legal newspaper of general publication and is now and has been for more than six NOTICE OFgppEA�HEARING— months prior to the date of publication, referred to, printed and published in the RENTONe HEARING EXAMINER English language continually as a daily newspaper in Kent, King County, RENTON,WASHINGTON Washington. The South County Journal has been approved as a legal Renton aring wi11 be held by the meetington, on Hearing Examiner at his regular newspaper by order of the Superior Court of the State of Washington for King seventh floor of C'?cil Chambers on the County. Grady Way, Renton Hall' 1055 South The notice in the exact form attached, was published in the South August 29, 2000, at 9:00 AM,Wastogconsider County Journal (and not in supplemental form) which was regularly distributed to the following petition: the subscribers durin the below stated eriod. The annexed notice, a A peal ofPEAL AD-00-098 g p ppeal of Determination of Nonsigni- ficance Mitigated in re Sunnydale Storm Appeal: AAD-00 098 System Replacement. The City of Renton is proposing replacement of the Sunnydale downstream system as published on: 8/18/00 (File No. LUA-00-071,E storm Location: SW of Sunnydale Mobile Home Park, Servic The full amount of the fee charged for said foregoing publication is the sum of North of SE 5th St. $37.38, charged to Acct. No. 8051067. Legal descriptions of the files noted above are on file in the Development Legal Numbe 89 Building, Division, sixth floor, Municipal g said g' Renton.All interested persons to petitions are invited to be present at the Public Hearing. Published in the South County Journal August 18,2000.8089 Legal erk, outh County Journal Subscribed and sworn before me on this X\ day of ,i - , 2000 `1111111611/rui, ,PA \�v,•,.•'`SO ie ,ice \ �� / ii i e �C /� _ P\---q _ -ii : ..,... act ss_ Z .' Pin1.1G 4 .. Notary Public of the State of Washington �j,,;4"ti off• c residing in Renton ',i#ii4:0 • I'f6•A, ,s% ‘`� King County, Washington iu 10. NOTICE OF APPEAL HEARING RENTON HEARING EXAMINER RENTON, WASHINGTON A Public Hearing will be held by the Renton Hearing Examiner at his regular meeting in the Council Chambers on the seventh floor of City Hall, 1055 South Grady Way, Renton, Washington, on August 29, 2000, at 9:00 AM, to consider the following petition: APPEAL AAD-00-098 Appeal of Determination of Nonsignificance Mitigated in re Sunnydale Storm System Replacement. The City of Renton is proposing replacement of the Sunnydale downstream storm system (File No. LUA-00-071,ECF). Location: SW of Sunnydale Mobile Home Park, North of SE 5th St. Legal descriptions of the files noted above are on file in the Development Services Division, sixth floor, Municipal Building, Renton. All interested persons to said petitions are invited to be present at the Public Hearing. Publication Date: August 18, 2000 Account No. 51067 aadpub • 6 a CIT' OF RENTON ••� Hearing Examiner Jesse Tanner,Mayor Fred J.Kaufman July 20,2000 Ms. Nicola Robinson 3110 SE 5th Street Renton, WA 98058-2824 Re: Appeal of DNS-M for Sunnydale Storm System Replacement Appeal File No. LUA-00-098,AAD Dear Ms. Robinson: Your letter of appeal in the above matter has been received and a date and time for said hearing have now been established. The appeal hearing has been set for Tuesday,August 29,2000, at 9:00 a.m. in the Council Chambers on the seventh floor of City Hall, at 1055 S Grady Way in Renton. Should you be unable to attend,would you please appoint a representative to act on your behalf. We appreciate your cooperation, and if you have any questions,please contact my secretary. Sincerely, Fred J. Kaufman Hearing Examiner FJK:mm cc: Mayor Jesse Tanner Jay Covington, Chief Administrative Officer Larry Warren, City Attorney Jana Hanson,Development Services Director John C. Ramsey Neal Whitney 1055 South Grady Way - Renton, Washington 98055 - (425)430-6515 Nicola Robinson 3110SE5t'St, • Renton,WA 98058-2824 Monday 17th July 2000 Mr,Fred Kaufman.Hearing Examiner. City of Renton:, 1055 South Grady Way, • CITY OF RENTQN Renton WA 98055 JUL '1 7 2000 Subject: Sunnydale Storm System Replacement: - Project No. LUA-00=071,ECF • RECEIVED - ' CITY CLERK'S OFFICE Dear Mr Kaufman, )/7?•dal• I am filing this appeal on behalf of many residents of the Maplewood community, "" • in response to the Determination of Non-significance-Mitigated with Mitigation measures in reference to the above-mentioned project. .. The designation of the area where the stream, (into which the Sunnydale Storm Water Run-off Pipe"•empties)and its attached wetland are located is `Resource Conservation.' I believe this is because of the sensitive nature of the area in term of the water bodies here,because it is part of a wild life corridor and because of the presence of • 'many,species of animals,including: deer, opossum, coyote, eagles, and herons-to name a few. I have photographs of a heron on the banks of the detention pond,and also resting in various trees. There could very well be a nesting area here as they,come every year. It would be important to pursue this issue further as pollution of the stream; detention pond" and potential degradation of the Wetlandwould put the wildlife here at risk.: The stream into which the storm water run off is to be discharged has been given ' ' the#29, but has not yet been placed on the `Sensitive(or Critical)Areas Map. The same is true of wetlands#48, both of which were documented in a memo dated September 25th, 1992 by Lynn Guttmann,P/B/PW Department'Administrator: (Enclosed)I received a letter from Mayor Jesse Tanner dated June the 2nd 2000, reassuring us that this error is being corrected. The Critical Areas Map available to the public at City Hall does not yet show this_correction. - Our concern reference,the above omission is that any maintenance proposal, • possible future request for development or rezoning will not take in to account the presence of a stream and wetland if they are not documented. The wetland borders the stream on the north side,the risk of flooding of the stream is always present and associated with this is the potential for•overflow into the wetland which would carry with it,:pollutants'from the storm water run-off Item I 1.1 Effects of Urbanization. Para 4 from the `Storm Water Management Manual-for the Puget Sound Basin. Run-off from urban areas has been shown to contain many different types-of.pollutants. The run-off from roads and highways is contaminated with oil and grease, lead, cadmium and other pollutants. Residential areas contribute herbicides, pesticides,fertilizers and animal waste to the run-off All of these can seriously impairobeneficial uses of receiving waters. The existing pipe carrying the run- off is old and its integrity is in question:.This may suggest that not all of the run-off is reaching its destination and to replace this pipe with a new one could therefor result in increased amounts of run-off The water in the stream at the point where the pipe empties its contents can be seen at times to be foaming, it does this all the way down to the .. detention pond. Neither the treatment facility for storm water in the Sunnydale Trailer Park and the detention pond into which the stream empties(where it once ran its full course as a ' , tributary of the Cedar River)meet current guidelines and are undersized to deal with the present load. Beneficial uses are impaired and threatened. Ongoing housing development and the'resulting mass cutting of trees above the slopes on the northerly border of the wetland pose.an ongoing threat to the integrity of the slopes and the ecosystem that is struggling for survival at its base.From this source may. - come additional polluted run-off, and from the stream yet more. Due to the critical nature ' of the area in whichthe stream and wetlands exist, and the ever present risk of degradation and contamination of the wetland from pollutants carried'in the stream; we respectfully request that an alternate dumping ground be located for the storm water run- off from the Sunnydale Trailer Park and,easements be applied for to this end. There are • ' laws in place that protect streams against degradation and that state `streams are not to'be - used as a means of conveyance for storm water run-off. As the presence of the Wetland and Stream have not been recorded and placed on the appropriate maps etc,we question whether an analysis has beep.performed on the ' wetland hydrology, and wetland water quality to show what the effects of this project will be on the health of the wetland?Have tests been performed to show what is being discharged into the stream that has the potential to adversely effect the wetland area? Thank you for your consideration of the above matter. sincerely: �" �C 3S l7- 5,. '. �-'S+ o- p cc: Jesse Tanner. Mayor. 4L n 98D5g City Council Members . otleA.4 qZ.7 "�2Y SE 5 Attachments: 1) Memo.From Lynn Guttman,P/B/PW Department Administrator. S . Ref: Maplewood Wetland and Sensitive Areas. Map. 2) Letter: Dated May 8th From Jesse Tanner,Mayor.- Ref'Maplewood Wetlands Map Designation..,Confirmation of their omission. Letter: Dated June 2nd From Jesse Tanner,Mayor. _ Ref Critical Areas Map Omission: Maplewood.Wetlands. ' 3) 8 Photographs of the stream and surrounding woods.Also a heron can be seen in the ' tree in 2 of the photographs. More photographs are available. .. fi rt CITI JF RENTON . ii Mayor Jesse Tanner June 2, 2000 Nicola Robinson 3110'SE 5t'Street Renton,WA 98058 SUBJECT: Critical Areas Map Omission-Maplewood Wetlands • Dear Ms.Robinson: Thank you for your letter of May 17, 2000, bringing this oversight to the City's attention. In fact, the critical areas map change described in,Lynn Guttmann's'memorandum was addressed in 1992. The revised version of the Wetlands and Streams ,Map showing Wetland W-48 and Stream S-29 was presented as a figure in the original 1993 adoption of the Land Use Element of the Comprehensive Plan. Unfortunately, the wrong version of this map was included in the current Critical Areas Ordinance. This error is being corrected. As a point of clarification, with the exception of the Steep Slopes Map, the maps in the Ordinance are not critical to the application of the regulations: Rather, the regulations are based on explicit criteria identified in the Code. The Wetlands Map is included for reference only. The 1991 wetlands mapping was gleaned from a variety of sources, including prior wetland studies, soil surveys, and aerial photos. Complete data on all wetlands within the City was not and is not now available. Consequently, the mapping was never intended to establish the presence or absence of wetlands at a specific location. At the time development is proposed for a particular site, disclosure of the existence of wetlands and delineation of their boundaries are required as part of the application and review, process. It is, however, the City's intent to provide the public with the best available information. Thank you again for your comments. erely, • Jesse Tanner Mayor • cc: City Clerk(Referral#20045-C) • City,Council Members•• ' ,. ... . . Jay Covington, Sue Carlson' Gregg'Ziinmei'inan'1 • ,. • , 1055 South Grady Way - Renton, Washington 98055 - (425)430-6500 /FAX(425)430-6523 This paper contains 50%recycled material,20%post consumer CITI 3F RENTON sal City Clerk Jesse Tanner,Mayor Marilyn J.Petersen May 18, 2000 Nicola Robinson 3110 SE 5th Street Renton, WA 98058 Re: Iviaplewood Wetlands Map Designation Dear Ms. Robinson: Thank you for your letter regarding the omission of the wetlands designation on the City's sensitive areas maps. Copies have been distributed to Mayor Jesse Tanner, members of the Renton City Council, and the Strategic Planning Division for review. A written response will be sent to you within the next two weeks. If I can provide additional information,please feel free to call. Sincerely, arilyn J t rsen - . City Clerk/Cable Manager cc: Mayor Jesse Tanner Council President Randy Corman Rebecca Lind, EDNSP Department 1055 South Grady Way - Renton, Washington 98055 - (425)430-6510 /FAX(425)430-6516 ®This paper contains 50%recycled material,20%post consumer CITY OF RENTON MEMORANDUM DATE: September 25, 1992 TO: R ton City Council via Mayor Earl Clymer FROM: nn isi ttmann, P/B/PW Department Administrator STAFF CONTACT: M. ne Myer, Principle Planner)'r14 SUBJECT: Maplewood Wetland and Sensitive Areas WETLAND: Recently, two residents representing the Maplewood Forest and Wildlife Society brought to the City's attention the existence of a wetland roughly six acres in size and two associated streams, all of which appear to have been overlooked by the City's wetland inventory. • On September 10, 1992, I met with Nicola Robinson at the site to verify this claim. At this site, I verified the presence of a wetland roughly 6 acres and the associated streams. The wetland is at the east end of a dirt road immediately north of the Maplewood subdivision. The wetland consists of an emergent wetland, scrub shrub, and forested wetland. Wetland plants present include cattails, sedges, skunk cabbage; willow, and alder, to name a few. A small man made detention pond also exists north of the same dirt road. The detention pond is associated with the lower reach of the stream near the Maple Valley highway. Because of its man made nature, this pond would not be classified as a wetland under:the wetland ordinance (Ord. #4346, Sec. 4-32-3.C.)The approximate locations of these sensitive areas were mapped based on the site visit, topographic maps, and aerial photographs. All pertinent elements of the City's critical areas inventory have been updated to include the wetland and associated streams. The wetland will be numbered W-48. The associated streams will be numbered S-29. LAND USE DESIGNATION: • Presently this area is designated Low Density Single Family in the Council's Preferred Land Use Alternative map. Underlying zoning could include G-1 (one dwelling unit per one acre) or RC, (one dwelling unit per 10 acres). The area-wide zoning process will address this area. Deadline for area-wide zoning requests is October 31, 1992. Requests may also be submitted during the neighborhood meetings to be held October 13, 20, 22, 27, 29, of 1992. The wetland, of course, will fall under the jurisdiction of the City's Wetland Ordinance (Ord. #4346) as well as the underlying zone. Transmitted with this memo are the following items: 1. A map showing the approximate location of the wetlands and streams based on the staff site visit, aerial photographs, and topographic maps (Exhibit A). 2. A letter from the Maplewood Forest and Wildlife Society to Mayor Clymer and City Council informing them of and describing sensitive areas adjacent to the Maplewood subdivision (Exhibit B). I A letter and Land Use map to Mary Lynne Myer from Steven Schwartz pointing out streams and a wetland behind his property that were not included in the wetland inventory (Exhibit C). 4. A hand written letter to Nicola Robinson, of the Maplewood Forest and Wildlife Society, from Ted Mallory describing the wildlife habitat associated with the wetland and surrounding area (Exhibit D). 5. A letter to Mary Lynne Myer, Principle Planner, from Philip Schneider, a habitat biologist with the Department of Wildlife, describing the wetland, creeks and upland habitat (Exhibit E). 6. A petition in support of preserving the Maplewood forest (Exhibit F). If you have any questions, please call David Saxen in Long Range Planning, 277-2475. t,,�-E-r c...A rJ D 1 S A r vLY 14 e.E - . . , M A R..su 3-c.,ai' -m,Ls •off., FoRz.srEo -r1_41N4, . --\--1.6S i s v„S-r A ri I S cA 1 W-'ia1Q, o c� M1o(2N Lk6 1-06E2S P)4er M �`rI1 out`T�t S r4 A -"c lS TEwriou Paip ergeiwl - ey(1-1-7 µI TLAt�1t� j * K* •4* AL (- per ,t•`�:4 . . • J iv";• x- sons Ns KiM1i •*• •�'� , 4 cum ' 4 * ♦ rt,tc p R •� y 44{* • �� fir t • 11 niul koLr \.t . le . I:6 CaJF90 gill! y .\ . . • • . . • NOTES . i fr NO RECEIPT . RATE I i-°" 12-9 6 RECEIVED FROM /V/C J Roibin ccrn ADDRESS 3)10 56 5E1 cigo5g $ 75.06 FOR A-ppeal (I-1;e ut A -oo-on) ACCOUNT HOW PAID AMT.OF ACCOUNT CASH • AMT. CHECK 75 ob PAID BALANCE MONEY BY.'"7/1 71ta,n1.-R7/1/11.- DUE ORDER 01998 REDIFORM®8L802 • EX ' : :. IBIT aIAIF CITY OF RENTON • DEVELOPMENT SERVICES DIVISION ENVIRONMENTAL CHECKLIST PURPOSE OF CHECKLIST: The State Environmental Policy Act(SEPA),Chapter-43.21C RCW,requires all governmental agencies to consider the environmental impacts of a proposal before making decisions. An Environmental Impact Statement(EIS)must be prepared for all proposals with probable significant adverse impacts on the quality of the environment. The purpose of this checklist is to provide information to help you and the agency identify impacts from your proposal(and to reduce or avoid impacts from the proposal,if it can be done)and to help the agency decide whether an EIS is required. INSTRUCTIONS FOR APPLICANTS: This environmental checklist asks you to describe some basic information about your proposal. Governmental agencies use this checklist to determine whether the environmental impacts of your proposal are significant,requiring preparation of an EIS. Answer the questions briefly,with the most precise information known,or give the best description you can. You must answer each question accurately and carefully,to the best of your knowledge. In most cases,you should be able to answer the questions from your own observations or project plans without the need to hire experts. If you really do not know the answer,or if a question does not apply to your proposal,write"do not know" or"does not apply". Complete answers to the questions now may avoid unnecessary delays later. Some questions ask about governmental regulations,such as zoning,shoreline,and landmark designations. Answer these questions if you can. If you have problems,the governmental agencies can assist you. The checklist questions apply to all parts of your proposal,even if you plan to do them over a period of time or on different parcels of land. Attach any additional information that will help describe your proposal or its environmental effects. The agency to which you submit this checklist may ask you to explain your answers or provide additional information reasonably related to determining if there may be significant adverse impact. USE OF CHECKLIST FOR NONPROJECT PROPOSALS: Complete this checklist for nonproject proposals,even though questions may be answered"does not apply." IN ADDITION, complete the SUPPLEMENTAL SHEET FOR NONPROJECT ACTIONS(part D). For nonproject actions(actions involving decisions on policies,plans and programs),the references in the checklist to the words"project," 'applicant,"and"property or site"should be read as"proposal," "proposer,"and"affected geographic area," respectively. A. BACKGROUND 1. Name of proposed project, if applicable: Sunnydale Downstream Storm System Replacement Project 2. Name of Applicant: City of Renton Surface Water Utility 3. Address and phone number of applicant and contact person: Allen Quynn 1055 South Grady Way _�" `" "• • Renton,Washington 98055 425-430-7247 &b�'sa i r't730 4. Date checklist prepared: 5/10/00 5. Agency requesting checklist: City of Renton 6. Proposed timing or schedule(including phasing,if applicable): The project will be constructed during the summer of 2000. Environmental Checklist 7. Do you have any plans for future additions, expansion, or further activity related to or connected to this project? D Yes ® No. If yes, explain. 8. List any environmental information you know about that has been prepared,or will be prepared, directly related to this proposal.. Geotechincal Report,Zipper Zeman Associates,May 2000. See Appendix A 9. Do you know whether applications.are pending for governmental approvals of other proposals directly affecting the property covered by your proposal? Yes ® No. If yes, explain. 10. List any governmental approvals or permits that will be needed for your proposal, if known. Washington State Dept.of Fish and Wildlife Hydraulic Project Approval Permit. 11. Give brief,complete description of your proposal, including the proposed uses and the size of the project and site. The proposed project is to replace an existing 700-foot-long corrugated metal stormwater with a new High-Density Polyethylene(HDPE) pipe of the same diameter. The project is needed to replace the existing storm system which is failing. The existing pipe is buried for a length of 160-feet along a flat section at the top of a slope. The remaining portion of the pipe is constructed above ground,down a steep slope. The upper 60-feet of the existing pipe has been partially crushed,resulting in joint separation and subsequent water leakage as well as reduction in the conveyance capacity of the pipe. One of the two manhole structures on the slope has been undermined and is in danger of collapsing. The buried portion of the existing pipe crosses over two Olympic Pipeline,Co.(OPLC) petroleum lines that run north-south along the top of the slope(see site map). The new pipe will be buried in the existing trench at the top of the slope,and will follow an improved above-ground alignment to the bottom. The invert elevation of the proposed pipe at the OPLC crossing will be set at a minimum of one-foot above the petroleum lines. The new pipe will be designed to maximize the vertical clearance between the two facilities. It is • anticipated that no clearing will be required,other than brush,for installation. The new pipe will have no intermediate structures,and will have an energy dissipator at the bottom to control scour. The existing pipe and structures will be removed as part of the project. The project will reduce erosion at the pipe outlet. It will reduce the chances of landslides occurring at the top of the slope from the leaking pipe,and will reduce the chances of landsliding or erosion occurring at other locations because of pipe leaks or the failure of structures. 12. Location of the proposal. Give sufficient information for a person to understand the precise location of your proposed project, including a street address, if any,and section,township,and range if know. If a proposal would occur over a range of area,provide the range or boundaries of the site(s). Provide a legal description, site plan,vicinity map, and topographic map, if reasonably available. While you should submit any plans required by the agency,you are not required to duplicate maps or detailed plans submitted with any permit applications related to this checklist. The project is located in SE'Is Section 16,Township 23N,Range 5E. The upper end is at the southeast corner of the Sunnydale Mobile Home Park. The lower end is near the intersection of SE 5th Street and Newport Avenue SE,north of the Maple Valley Highway. See Appendix B. A maintenance access road to the outlet is entered off of Maple Valley Road near the west end of SE 5th Street. w:projects/00050/SEPA/sunnychecklist(05/18/00)Imp Page 2 • . • ,) Environmental Checklist B. ENVIRONMENTAL ELEMENTS 1. EARTH a. General description of the site: ❑ flat ❑ rolling ® hilly ® steep slopes in mountainous ❑ other For detailed information the soils condition on site, see the attached Field Exploration and Geotechnical Study(Zipper-Zeman 2000). b. What is the steepest slope on the site(approximate percent slope?) The steepest slope on the site is 70 percent. c. What general types of soils are found on the site(for example, clay, sand,gravel, peat, muck)? If you know the classification of agricultural soils, specify them and note any prime farmland. According to the Soil Survey King County,Washington(USDA Soil Conservation Service 1973),the area soils consist of Alderwood and a small amount of Puyallup soils at the lower end of the project. Alderwood soils consist primarily of gravelly sandy loam and Puyallup soils consist primarily of fine sandy loam. Also refer to the Field Exploration and Geotechnical Study(Zipper-Zeman 2000). d. Are there surface indications or history of unstable soils in the immediate vicinity? If so, describe. From Station 3+42 to 3+86,there is evidence of the remnant of a shallow landslide/erosional scar. From approximately Station 4+50 to 5+50,there is the presence of several trees with curving and leaning trunks,suggesting that the vegetation is subject to slow downslope creep of near surface soils. For more detailed information refer to the Field Exploration and Geotechnical Study(Zipper-Zeman 2000). e. Describe the purpose,type, and approximate quantities of any filling or grading proposed. Indicate source of fill. Approximately 352 cubic yards of soil would be disturbed during pipe installation. There would,be approximately 88 cubic yards of soil removed during construction of the outfall structure. The existing rock buttress will be dismantled and reassembled on-site. Some additional rock backfill for drainage will be placed at the rock buttress. Approximately 16 cubic yards of controlled density fill will be installed within the trench to protect the existing gas pipelines. f. Could erosion occur as a result of clearing, construction, or use? If so,generally describe. Erosion could occur when the soils are exposed during construction. It is anticipated that construction will be completed within three to four weeks. g. About what percent of the site will be covered with impervious surfaces after project construction (for example,asphalt or buildings)? There would be no new impervious surface area. • w:projects/00050/SEPA/sunnychecklist(05/18/00)Imp Page 3 . t Environmental Checklist h. Proposed measures to reduce or control erosion,or other impacts to the earth, if any: Only minor clearing of brush will occur along the aboveground alignment,with some hand digging in one location_The project would follow best management practices(BMPs) to control erosion. Construction is expected to be completed within a three to four-week time frame. The exposed soils at the catch basin outlet would be seeded. 2. AIR a. What types of emissions to the air would result from the proposal(i.e.,dust,automobile, odors, and industrial wood smoke)during construction and when the project is completed? If any,generally describe and give approximate quantities if known. During construction,emissions from construction equipment would be generated. b. Are there any off-site sources of emission or odor that may affect your proposal?❑ Yes®No. If so, generally describe. None. c. Proposed measures to reduce or control emissions or other impacts to air, if any: None. 3. WATER a. Surface Water: 1) Is there any surface water body on or in the immediate vicinity of the site(including year-round and seasonal streams,saltwater, lakes,ponds,wetlands)?® Yes ❑ No. If yes, describe type and provide names. If appropriate, state what stream or river it flows into. A year-round groundwater fed stream follows the lower portion of the existing alignment to the outlet and is tributary to the Cedar River. 2) Will the project require any work over, in,or adjacent to(within 200 feet)the described waters? Yes❑ No. If yes, please describe and attach available plans. The existing pipe,manholes,and pipe supports would be removed by hand as part of the project. Approximately 800-feet of storm pipe will be constructed within 200-feet of the stream. The majority of the pipe or approximately 700-feet will be constructed above ground. The lower end of the new alignment will include an energy dissipator and approximately 100-feet of buried storm pipe adjacent to the stream. To minimize the introduction of sediment into the stream during the construction of the outfall structure,a temporary 18-inch bypass pipe will be installed to divert flows around the construction area. The pipe will be laid along the streambed on the opposite side of construction,beginning at a point approximately 20 feet upstream of the proposed structure. A sandbag headwall will be constructed by hand around the end of the pipe to act as a dam and direct the stream flow into the pipe. Plastic sheeting will be used on the upstream side of the headwall to minimize infiltration through the sandbags. The bypass pipe will discharge approximately 20 feet downstream of the energy dissipator. w:projects/00050/SEPA/sunnychecklist(05/18/00)Imp Page 4 • .t Environmental Checklist 3) Estimate the amount of fill and dredge material that would be placed in or removed from surface water or wetlands and indicate the area of the site that would be affected. Indicate the source of fill material. None. - 4) Will the proposal require surface water withdrawals or diversions? Give general description, purpose, and approximate quantities if known. No. 5) Does the proposal lie within a 100-year flood plain?❑ Yes ® No. If so,note location on the site plan. 6) Does the proposal involve any discharges of waste materials to surface waters? ❑ Yes ® No. If so,describe the type of waste and anticipated volume of discharge. b. Ground Water: 1) Will ground water be withdrawn,or will water be discharged to ground water? Give general description,purpose,and approximate quantities if known. No. 2) Describe waste material that will be discharged into the ground from septic tanks or other sources, if any(for example: Domestic sewage; industrial,containing the following chemicals..; agricultural;etc.). Describe the general size of the system,the number of such systems,the number of houses to be served(if applicable),or the number of animals or humans the system(s)are expected to serve. None. c. Water Runoff(including storm water): 1) .Describe the source of runoff(including storm water)and method of collection and disposal, if any (include quantities,if known). Where will this water flow? Will this water flow into other waters, If so,describe. The proposed project will convey stormwater runoff from the Sunnydale Mobile Home Park down a steep slope to an energy dissipator at the base of the slope.The energy dissipator will then discharge the storm runoff into a natural groundwater fed stream which continues west for approximately 1,300 feet and enters two small detention ponds in series. Where the stream enters the first pond,a second outfall discharges additional runoff from a storm system serving the Maplewood Subdivision. Once the stream exits the last detention pond,it enters a 24-inch storm pipe which conveys the stream across the Maple Valley Highway for approximately 350-feet before discharging into the Cedar River. 2) Could waste material enter ground or surface waters? If so, generally describe. No. d. Proposed measures to reduce or control surface, ground,and runoff water impacts, if any: The purpose of the project is to reduce runoff water impacts. It will replace an existing pipe,which is in poor condition and leaking,with a more reliable pipe. It will also replace an eroding outfall with an energy dissipator to reduce erosion and scour. During construction,a flow bypass system will be installed which conveys any stormwater safely. down the existing pipe,until the new pipe is installed. Erosion control BMPs will also be used during construction. w:projects/00050/SEPA/sunnychecklist(05/18/00)Imp Page 5 . t Environmental Checklist 4. PLANTS a. Check types of vegetation found on the site: ®deciduous tree: alder,maple,aspen,other 1Z1 evergreen tree: fir,cedar,pine,other ®shrubs grass ID pasture crop or grain wet soil plants:cattail,buttercup,bullrush,skunk cabbage,other water plants:water lily,eel grass,milfoil,other ®other types of vegetation b. What kind and amount of vegetation will be removed or altered? Some brush and blackberries would be cleared at the top of the project where the pipe is buried. For the portion of the alignment where the pipe is above ground,only a minimal amount of vegetation will be cleared by hand. No trees would need to be removed. Some grasses would be disturbed for construction of the energy dissipator. c. List threatened or endangered species known to be on or near the site. Do not know. d. Proposed landscaping,use of native plants,or other measures to preserve or enhance vegetation on the site, if any: Natural grass seed would be used to replant on any disturbed soils. 5. ANIMALS a. Circle any birds and animals which have been observed on or near the site or are known to be on or near the site: (see next page) Birds: hawk,heron,eagle,songbirds,other Mammals: deer,bear,elk,beaver,other raccoons Fish: bass, salmon,trout,herring,shellfish,other Frogs,(see 5b.,below) b. List any threatened or endangered species known to be on or near the site. Down gradient of the site approximately'A mile is the Cedar River. The Cedar River is used by migrating adult and juvenile chinook salmon(Oncorhynchus tshawystscha),coho salmon(Oncorhynchus kisutch),and native char,including bull trout(Salvelinus confluentus). Only Chinook Salmon and Bull Trout are presently listed as threatened. c. Is the site part of a migration route? If so,explain The project is within the Pacific Flyway. d. Proposed measures to preserve or enhance wildlife, if any: None. 6. ENERGY AND NATURAL RESOURCES a. What kinds of energy(electric,natural gas,oil,wood stove, solar)will be used to meet the completed project's energy needs? Describe whether it will be used for heating, manufacturing, etc. None. w:projects/00050/SEPA/sunnychecklist(05/18/00)Imp Page 6 Environmental Checklist b. Would your project affect the potential use of solar energy by adjacent properties? If so, generally describe. - No. c. What kinds of energy conservation features are included in the plans of this proposal? List other proposed measures to reduce or control energy impacts, if any: None. 7. ENVIRONMENTAL HEALTH a. Are there any environmental health hazards, including exposure to toxic chemicals, risk of fire and explosion, spill,or hazardous waste,that could occur as a result of this proposal? If so, describe. Fuel or oil spills could occur from construction equipment. 1) Describe special emergency services that might be required. None. 2) Proposed measures to reduce or control environmental health hazards, if any: Refueling of equipment would not occur in sensitive areas. Equipment would be checked for oil leaks and repaired before returning to site. b. Noise 1) What types of noise exist in the area which may affect your project(for example: traffic, equipment,operation,other)? None. 2) What types and levels of noise would be created by or associated with the project on a short-term or a long-term basis(for example:traffic,construction,operation,other)? Indicate what hours noise would come from the site. Short-term noise would be generated from construction equipment and could go as high as 90 dBA. No long-term noise would be generated from the project. 3) Proposed measures to reduce or control noise impacts, if any: None are proposed. 8. LAND AND SHORELINE USE a. What is the current use of the site and adjacent properties? The site is currently a greenbelt and consists of forested steep slopes. Residential land uses are located atop the steep slopes,as well as at the bottom. b. Has the site been used for agriculture?❑ Yes ® No. However,the site may have been used historically to harvest timber. c. Describe any structures,on the site. None. - w:projects/00050/SEPA/sunnychecklist(05/18/00)Imp Page 7 Environmental Checklist d. Will any structures be demolished? ® Yes [] No. If so,what? An existing corrugated metal pipe,two catchbasins,and some pipe support structure, including an I-beam,will be removed an disposed of. e. What is the current zoning classification of the site? RC—Resource Conservation f. What is the current comprehensive plan designation of the site? Residential Rural g. If applicable,what is the current shoreline master program designation of the site? Does not apply. h. Has any part of the site been classified as an "environmentally sensitive" area? If so,specify. The existing and proposed pipe is on slopes greater than 40 percent. i. Approximately how many people would reside or work in the completed project? Does not apply. j. Approximately how many people would the completed project displace? Does not apply. k. Proposed measures to avoid or reduce displacement impacts, if any: Does not apply. 1. Proposed measures to ensure the proposal is compatible with existing and projected land uses and plans, if any: The steep slopes preclude any future development. 9. HOUSING a. . Approximately how many units would be provided, if any? Indicate whether high, middle, or low- income housing. Does not apply. b. Approximately how many units, if any,would be eliminated? Indicate whether high, middle, or low-income housing. Does not apply. c. Proposed measures to reduce or control housing impacts, if any: Does not apply. 10. AESTHETICS a. What is the tallest height of any proposed structure(s),not including antennas;what is the principal exterior building material(s)proposed. Energy dissipator structure will extend approximately 20 inches above ground. b. What views in the immediate vicinity would be altered or obstructed? None c. Proposed measures to reduce or control aesthetic impacts, if any: Does not apply. w:projects/00050/SEPA/sunnychecklist(05/18/00)Imp Page 8 Environmental Checklist ,11. LIGHT AND GLARE a. What type of light or glare will the proposal produce?None What time of day would it mainly occur?Does not apply. b. Could light or glare from the finished project be a safety hazard or interfere with views?No c. What existing off-site sources of light or glare may affect your proposal?None d. Proposed measures to reduce or control light and glare impacts, if any:Does not apply. 12. RECREATION a. What designated and informal recreational opportunities are in the immediate vicinity? None known b. Would the proposed project displace any existing recreational uses? ❑ Yes ® No. If so, describe. c. Proposed measures to reduce or control impacts on recreation, including recreation opportunities to be provided by the project or applicant, if any: Does not apply. 13. HISTORIC AND CULTURAL PRESERVATION a. Are there any places or objects listed on,or proposed for,national state,or local preservation registers known to be on or next to the site? If so, generally describe. None known. b. Generally describe any landmarks or evidence of historic,archaeological,scientific, or cultural importance known to be on or next to the site. Does not apply. c. Proposed measures to reduce or control impacts, if any: Does not apply. • 14. Transportation a. Identify public streets and highways serving the site,and describe proposed access to the existing street system. Show on site plans, if any. During construction,the top would be accessed from an existing maintenance road southwest of the Sunnydale Mobile Home Park,off of Union Avenue NE. The bottom of the project would be accessed through an existing maintenance road on the north side of the Maple Valley Highway,west of SE 5th Street. b. Is site currently served by public transit? If not,what is the approximate distance to the nearest transit stop? Does not apply. c. How many parking spaces would the completed project have? How many would the project eliminate? None d. Will the proposal require any new roads or streets, or improvements to existing roads or streets,not including driveways? If so, generally describe(indicate whether public or private? No w:projects/00050/SEPA/sunnychecklist(05/18/00)Imp Page 9 • Environmental Checklist e. Will the project use(or occur in the immediate vicinity of)water,rail, or air transportation? If so, generally describe. No f. How many vehicular trips per day would be generated by the completed project? If known, indicate when peak volumes would occur. Does not apply. g. Proposed measures to reduce or control transportation impacts, if any: Does not apply. 15. Public Services a. Would the project result in an increased need for public services (for example: fire protection, police protection,health care, schools,other)? If so, generally describe. No b. Proposed measures to reduce or control direct impacts on public services, if any. Does not apply. 16. Utilities a. Circle utilities currently available at the site: electricity, natural gas,water, refuse service, telephone,sanitary sewer, septic system, other. Olympic Pipeline Co.has two petroleum lines that cross the existing storm line at the top of the slope. b. Describe the utilities that are proposed for the project,the utility providing the service,and the general construction activities on the site or in the immediate vicinity which might be needed. None. • w:projects/00050/SEPA/sunnychecklist(05/18/00)Imp Page 10 Environmental Checklist .C. SIGNATURE I,the undersigned,state that to the best of my knowledge the above information is true and complete. It is understood that the lead agency may withdraw any declaration of non-significance that it might issue in reliance upon this checklist should there be any willful misrepresentation or willful lack of full disclosure on my part. hit) Proponent: C ,"- 2./(,. •,vim/ Name Printed: A-11,,, (4, iiYl Date: 6 I 1/oo w:projects/00050/SEPA/sunnychecklist(05/18/00)Imp Page 11 APPENDIX A Geotechnical Report Zipper Zeman Associates, Inc. Geotechnical and Environmental Consulting J-686 10 May 2000 EntrancoAI; 10900 N.E. 8t1i Street, Suite 300 ;;`4 Bellevue, Washington 98004 ENT NCO Attention: Mr. Bruce Jensen MAY 1 1 2000 Subject: Field Exploration and Geotechnical Engineering Study RECEIVED Proposed Sunnydale Downstream SIP Renton, Washington Entranco Project No. 1-10-00050-20 • Dear Mr. Jensen: Zipper Zeman Associates, Inc. (ZZA) is pleased to present herein a copy of the above- referenced report. This report presents the results of our surface mapping, subsurface exploration, and geotechnical engineering study relative to pipeline siting and construction aspects of the proposed project. Our services have been provided in accordance with the terms of our Subconsultant Agreement dated 13 March 2000. The purpose of the study was to establish general surface and subsurface conditions at the site from which conclusions and recommendations regarding storm water pipeline and structure design and construction considerations could be formulated. The scope of our services consisted of field explorations, laboratory testing, geotechnical engineering analysis, and preparation of this report. Our scope of services did not include sampling or testing of soil or water for regulated environmental contaminants. Should the nature of the proposed site improvements change from those described herein, we recommend that our firm be provided the opportunity to review the plans in order to verify that the conclusions and recommendations presented in this report are appropriate for the design. This report is an instrument of service, and has been prepared in accordance with generally accepted geotechnical engineering practices for the exclusive use of Entranco, the City of Renton, and their agents, for specific application to this project and site location. SITE AND PROJECT DESCRIPTION The project site spans the area extending from the Sunnydale residential development located on the north hillside overlooking the Cedar River valley, toward the residential neighborhood located along S.E. 5th Street near the toe of the hillside. The site encompasses an existing drainage easement and adjacent areas, as shown on the Vicinity Map, Figure 1. The proposed project entails replacing existing storm water drainage system components between the detention pond located at the top of the hillside and the end of an above ground tightline terminating in a creek at the bottom of the hillside. Currently proposed project elements include: 19321 36ih Avenue West,Suite B201 Lynnwood,Washington 98036 (425)771 -3304 Proposed Sunnydale Downstream SIP J-686 Renton, Washington '`� `m ' 10 May 2000 Page 2 • Replacement of approximately 160 feet of 18-inch buried corrugated metal pipe (CMP) with a buried HDPE pipe; • Replacing an existing above ground 18-inch CMP with an 18-inch inside-diameter HDPE pipe installed at along a different alignment. The proposed tightline alignment is approximately 700.feet long; • Installing a stilling well energy dissipator adjacent to the creek a short distance downstream of the existing CMP terminus. SITE CONDITIONS The site conditions for the preliminary study were evaluated in March and April 2000. The surface and subsurface conditions are described below, while the exploration procedures and interpretive logs of the explorations are presented in Appendix A. Laboratory testing procedures and results are presented in Appendix B. The proposed site development and approximate exploration locations are shown on the Site and Exploration Plan, Figure 2. Surface Conditions The project site can be characterized as containing a developed upland including and adjacent to the Sunnydale development, and an undeveloped ravine and lowland. For descriptive purposes we have broken the site into these two areas, as presented below. Developed Upland The upper portion of the site comprised a relatively level area located south of, and behind, the residences along Madrona Drive, the southernmost street in the Sunnydale neighborhood. A gravel surface road extended south from Madrona Drive, accessing a storm water detention pond located east of the road. A control manhole was located west of the pond and road, adjacent to a moderately steep slope that extended downward in a westerly direction to a utility easement. The upland area adjacent to the pond was at approximately elevation 310 to 312 feet. Lawn bordered the pond and access road, while a thick growth of blackberry bushes mantled the slope to the west. The detention.pond contained water at the time of our site visits, and some standing water was present on the access road. The overgrown slope extending below the pond access road dropped approximately 12 to 15 feet at an inclination of approximately 30 to 35 percent. A portion of the slope approximately 25 to 50 feet southwest of the upper manhole, was oversteepened and mantled with large rock. As will be discussed subsequently, the rock was placed as part of efforts to repair an erosional scar on the steep slope. Zipper Zeman Associates,Inc. 19231 36"'Avenue West,Suite B201 Lynnwood,Washington 98036 (425)771 -3304 - Fit Proposed Sunnydale Downstream SIP J-686 Renton, Washington 10 May 2000 Page 3 A cleared easement containing overhead electrical transmission lines and two underground petroleum pipelines bordered the slope below the pond and access road. The cleared portion of the easement was about 40 feet wide, and sloped downward to the west approximately 6 feet over its width west of the pond. A catch basin was located on the west side of the easement. The catch basin lid was at an elevation of approximately 284 feet, according to survey information provided to us by Entranco. A buried 18-inch diameter CMP extended between the upper manhole and the lower catch basin. The burial depth ranged from about 12 feet at the upper manhole to about 3 feet at the western catch basin. For descriptive purposes, we considered the catch basin the western extent of the developed upland portion of the site. Undeveloped Ravine A large ravine extended in a southwesterly direction from the petroleum pipeline easement. The ravine terminated on the north side of the Cedar River valley, approximately 600 feet west of the easement. Ground surface elevations from the western catch basin and the end of the ravine ranged from approximately 284 to 90 feet. The south side of the ravine had inclinations ranging from about 23 to 67 percent, with the slope inclination generally increasing in proximity to the slope toe. The inclination of the north side of the ravine was slightly steeper overall. The ravine sideslopes were well vegetated with brush and both deciduous and evergreen trees. A shallow stream flowed in the ravine bottom. Erosion of the ravine was evidenced by the incised nature of the channel with steep sideslopes. An 18-inch CMP extended from the west side of the catch basin on the west side of the petroleum pipeline easement above the ravine. The CMP extended essentially down the fall line of the ravine sideslope for a distance of about 215 feet. The CMP entered a manhole at the toe of the steep slope. The remainder of the CMP was located on a narrow shelf excavated near the toe of the ravine's north sideslope, a few feet above the stream below. The lowermost portion of the CMP extending toward the manhole in the creek was supported by timber and steel cribbing. The manhole was undermined, and supported in part by a piece of wood blocking jammed between the manhole bottom and the streambed below. The CMP was locally deformed from • having been impacted by falling trees. The CMP terminated approximately 360 feet downstream of the manhole. Water from the CMP discharged approximately 4.3 feet above the streambed. Surface Conditions—Proposed Tightline Alignment • The project includes abandoning the existing above ground CMP and replacing it with an above ground HDPE tightline following a different alignment. The proposed alignment extends across and down the south side of the ravine, approximately as shown on Figure 2. Surface conditions along the proposed tightline alignment are described below. For discussion purposes, we designated the existing catch basin at the west side of the petroleum pipeline easement as Station 0, and walked the alignment to the west, finishing at approximately Station 7+12, the downstream end of the HDPE tightline and proposed stilling well energy dissipator location. Zipper Zeman Associates, Inc. 19231 36''Avenue West,Suite B201 Lynnwood,Washington 98036 (425)771 -3304 • . 1 , Proposed Sunnydale Downstream SIP • >'y .0.41 J-686 Renton, Washington 10 May 2000 Page 4 Station 0+00 to Station 0+70 The alignment along this interval extended from the west side of the existing catch basin down a steep slope with an inclination of approximately 35 degrees from horizontal. The slope was mantled with both brush and trees, and lacked surficial evidence of landslide activity or significant erosion. Station 0+70 to Station 1+30 The slope inclination along this interval was approximately 30 degrees from horizontal, and like the steeper section above, lacked evidence of slope instability or surface water erosion. Station 1+30 to Station 3+10 This portion of the alignment followed a relatively gently sloping path cutting across the upper reaches of the south ravine sideslope. The cross slope inclination was as steep as approximately 25 percent. The hillside was mantled with a well-developed growth of deciduous and evergreen trees, as well as brush. Station 3+10 to Station 3+42 The cross slope inclination along this interval of the alignment increased to approximately 35 percent,based upon hand held clinometer measurements. Station 3+42 to Station 3+86 The alignment crossed the remnant of a shallow landslide/erosion scar along this section. The middle of the feature was 2 to 3 feet deeper than the adjacent grades on either side, and was well vegetated. • Station 3+86 to Station 4+10 This portion of the alignment comprised an undisturbed, open section of slope lacking evidence of past earth movement or significant erosion. Station 4+10 to Station 4+50 This 40-foot long interval of the alignment spans a slight depression most likely produced by soil and root displacement resultant from a large tree having fallen over. The center of the feature was 3 to 4 feet below the adjacent grade at either side. Zipper Zeman Associates, Inc. 19231 36'1'Avenue West,Suite B201 Lynnwood,Washington 98036 (425)771 -3304 L ....ram. 4;.= r Proposed Sunnydale Downstream SIP ; J-686 Renton, Washington • 10 May 2000 Page 5 Station 4+50 to Station 5+50 The 100-foot long section extended downslope toward the toe of the south side of the ravine, extending through a brush-covered area. The presence of several trees with curving and leaning trunks suggest that the vegetation is subject to solifluction, or slow downslope creep of near surface soils, as well as phototropism. Station 4+50 to Station 7+12 This interval of the alignment followed the south side of the stream channel flowing out of the steep sided ravine. The south side of the stream contained a sparse vegetation growth and abundant riprap immediately adjacent to the stream. The stream channel was about 3 to 4 feet along this interval. The channel bank at the proposed energy dissipator location was characterized by brush, bare ground, and some saplings. Subsurface Conditions Subsurface conditions were explored by advancing borings adjacent to the existing buried CMP near the detention pond and along the east side of the petroleum pipeline easement (B-1, B-2), by excavating two test pits (TP-1, TP-2) at the downstream end of the proposed tightline alignment where the energy dissipator will be installed, and by advancing four hand explorations (HA-1 through HA-4) on the south side of the ravine along the proposed tightline alignment. Soil descriptions presented in this report are based on the subsurface conditions encountered at specific exploration locations across the site. Variations in subsurface conditions may exist between the exploration locations and the nature and extent of variations between the explorations may not become evident until construction. If variations then appear, it may be necessary to reevaluate the recommendations of this report. The publication Preliminary Geologic Map of Seattle and Vicinity, Washington (U.S.G.S. Map I-354, 1962) describes the upland portion of the site as underlain by recessional outwash sand and gravel above Vashon glacial till. The recessional outwash is a normally consolidated granular soil deposit, generally characterized by a moderate to high permeability and susceptibility to erosion by flowing water. The glacial till is a glacially consolidated, heterogeneous soil with a wide ranging grain size distribution. The till is underlain by "older clay", a combination of clay, sand, and gravel, and advance outwash deposits. The advance outwash can contain sand, silt, clay, and some gravel horizons. The material is glacially consolidated. The referenced map describes the soils at the bottom of the ravine and in close proximity to the steep slopes on the north side of the Cedar River valley as older landslide deposits. Subsurface conditions as disclosed by the explorations completed for this study confirmed the presence of the soils described in the publication, and also disclosed fill material, as described below. Zipper Zeman Associates, Inc. 19231 36"'Avenue West,Suite B201 Lynnwood,Washington 98036 (425)771 -3304 Proposed Sunnydale Downstream SIP J-686 Renton, Washington 10 May 2000 Page 6 Developed Upland Area Boring B-2, advanced along the'existing buried CMP southwest of the upper manhole, disclosed approximately 16.5 feet of loose to medium dense, moist, brown, gravelly, silty sand and sandy gravel fill material. The fill was underlain by very stiff, moist, blue-gray silt to the boring's termination depth of 21.5 feet below grade. Boring B-2, advanced along the buried CMP at the east side of the petroleum pipeline easement, disclosed soft to stiff silt and gravelly silt with some interbedded fine sand soils to the boring's termination depth of 11.5 feet below grade. Groundwater was not encountered at either of the two boring locations at the time of drilling. Undeveloped Ravine Hand explorations HB-1 through HB-4 were advanced along the proposed tightline alignment as shown on Figure 2. Each of the explorations disclosed a surficial organic forest duff horizon underlain by loose gravelly sand or soft silt with some fine sand. These soils were underlain by loose to dense sand and stiff to very stiff sandy silt. These lower soils are representative of the advance outwash materials. Slight groundwater seepage was observed at a depth of 2.7 feet while advancing boring HB-1. Test pits TP-1 and TP-2 were excavated at the mouth of the ravine at prospective energy dissipator locations. Test pit TP-1, located near the existing CMP outfall, disclosed approximately 6 feet of medium dense gravelly sand fill. The fill had a variable silt content, and contained some angular gravel and cobbles, as well as organic material. A relic topsoil horizon was encountered at a depth of about 6 to 6.5 feet. The old topsoil was underlain by approximately 1.5 feet of stiff to very stiff sandy silt with some gravel and interbedded sand. The test pit was terminated at a depth of 11 feet in a medium dense silty sand with some gravel and interbedded sandy silt. Slow groundwater seepage was observed at a depth of 9.5 feet at the time of excavation. Test pit TP-2 was excavated approximately 100 feet downstream of the existing CMP outfall. Approximately 3 feet of loose to medium dense gravelly sand with some silt (fill material) was observed at this location, above relic topsoil that extended to a depth of approximately 3.5 feet. The relic topsoil was underlain by soft to medium stiff sandy silt with some organics and trace gravel to a depth of approximately 6 feet below grade. This material is likely colluvium, or soil that has migrated downslope resultant from natural mass wasting processes, in our opinion. The colluvium was underlain by stiff to very stiff sandy silt and medium dense gravelly sand to the test pit's 10-foot termination depth. Rapid groundwater seepage at a depth of 8 feet below grade was observed. Conditions observed at the exploration locations are summarized in the table below. Zipper Zeman Associates, Inc. 19231 36"'Avenue West,Suite B201 Lynnwood,Washington 98036 • (425)771 -3304 Proposed Sunnydale Downstream SIP `) '' J-686 Renton, Washington 10 May 2000 Page 7 • Exploration Summary Exploration Ground Surface Fill Thickness(feet) Depth to Med. Groundwater Elevation(feet)* Dense/Medium Depth(feet)** Stiff Soils(feet) B-1 289 NE 0 NE B-2 312 16.5 0 NE TP-1 103 6 6.5 9.5 TP-2 90 . 3 5 8 HB-1 220 NE 2.5 2.7 HB-2 196 NE 2 NE HB-3 178 NE 2 NE HB-4 172 NE 1.5 NE * Ground surface elevations referenced topography shown on plan provided by Entranco; ** Groundwater conditions may vary due to weather,irrigation,and other factors; NE: Not Encountered S.C.S. Soil Descriptions Review of the Soil Survey of King County Area, Washington (U.S.D.A., Soil Conservation Service,November 1973) identified the site as mantled by three major soil types: • Alderwood gravelly sandy loam(6 to 15 percent slopes) near the detention pond. These soils are formed in glacial tills, and are characterized by a relatively low permeability and moderate erosion potential; • Alderwood and Kitsap soils (very steep) below the easement through the ravine. The Alderwood and Kitsap soils are derived from glacially consolidated materials, and are present on steep slopes. The soils may exhibit a severe to very severe erosion potential and a severe slippage potential; • Puyallup fine sandy loam has been mapped in the valley bottom. The Puyallup soils are described as loamy sands with a,slight erosion potential. Groundwater Groundwater seepage was observed at the locations of test pits TP-1 and TP-2 at depths of approximately 9.5 and 8 feet, respectively. Slight seepage was observed at the hand boring HB-1 location at a depth of 2.7 feet. Groundwater was not encountered while drilling borings B-1 and B-2. A perched groundwater condition can sometimes develop within glacially consolidated soils, due to their relatively high fines content and density producing a low permeability, or within interbedded granular and fine grained soils. It should be noted that groundwater conditions may fluctuate due to seasonal precipitation variation, site utilization, irrigation, and other factors. Zipper Zeman Associates, Inc. 19231 36''Avenue West,Suite B201 Lynnwood,Washington 98036 (425)771 -3304 • Proposed Sunnydale Downstream SIP " 1, J-686 Renton, Washington 10 May 2000 Page 8 Seismic Criteria Figure 16-2 presented in the 1997 Uniform Building Code classifies the subject site as being within Seismic Zone 3. Based on the subsurface conditions encountered at the site and published geologic literature, it is our opinion that a Soil Profile Type of Sc should be used to describe the average properties within the upper 100 feet of soil beneath the site. This designation describes soils that are considered very dense with a shear wave velocity of 1,200 to 2,500 feet per second, Standard Penetration Test values greater than 50, and an undrained shear strength of greater than 2,000 psf. The publication Liquefaction Susceptibility for the Des Moines and Renton 7.5-minute Quadrangles, Washington (Washington Division of Geology and Earth Resources, GM-41, 1994) describes the developed upland and undeveloped ravine portions of the site as having a Category III liquefaction susceptibility risk. A Category III characterization reflects a low liquefaction susceptibility, generally reflecting glacially consolidated soils. The valley margin immediately adjacent to the site (areas containing mass wasting and colluvial deposits) are described as a Category II liquefaction risk. The nomenclature considers a Category II risk low to high. CONCLUSIONS AND RECOMMENDATIONS Site improvement plans consider replacing approximately 160 feet of buried storm sewer with a new buried 18-inch diameter HDPE pipe near the Sunnydale development, installing approximately 700 feet of new 18-inch diameter HDPE pipe (about 550 feet on the surface and about 150 feet buried), and constructing a stilling well energy dissipator. Based upon the site conditions observed during our exploration, the project appears feasible from the geotechnical perspective. Selected considerations include: • Subsurface conditions observed along the buried portion of the pipe near the detention pond comprise native silt and silty sand soils, as well as sandy gravel and gravelly sand fill. Groundwater was not disclosed at the exploration locations along the buried pipe alignment; • Re-use of the existing granular fill as trench backfill for the upper buried pipe section is feasible. Re-use of the native fine grained soils will depend upon the material's moisture content at the time of compaction. Budget provisions for importation of granular backfill and removal of the fine grained soils is recommended; • Placement of the HDPE pipe on the ground surface between the petroleum pipeline easement and the bottom of the slope about 150 feet above the stilling basin is feasible. Limited hand excavation and shallow pipe burial is recommended at three locations along the surface alignment so that the pipe can be placed on the surface along two shallow depressions; • Conventional pre-cast manhole structure installation for the proposed stilling well energy dissipator is feasible. Dewatering at the time of excavation and structure placement should Zipper Zeman Associates, Inc. 19231 3611'Avenue West,Suite B201 Lynnwood,Washington 98036 (425)771 -3304 � . Proposed Sunnydale Downstream SIP t:�,, J-686 Renton, Washington 10 May 2000 Page 9 be anticipated is the structure is founded at or below the depth where groundwater seepage was observed at the test pit TP-2 location; • Re-use of non-organic soils excavated along the lower section of buried HDPE, and at the energy dissipator location, is considered feasible. Presented below are our conclusions and recommendations regarding environmentally sensitive areas, trench excavation and backfilling, structure foundation subgrade preparation, and tightline anchorage. Environmentally Sensitive Area Considerations Erosion Hazard The sloping upland portion of the site, downslope of the detention pond access road and the toe of slope about 150 feet above the energy dissipator location, represents a potential erosion hazard, in our opinion, and should be considered sensitive to uncontrolled surface water flow during and after construction. Fortunately, excavation along this portion of the project is expected to be minimal, limited to the petroleum pipeline easement and three small sections along the surface tightline alignment. Potential erosion in these areas during construction can be reduced by following commonly accepted Best Management Practices such as diverting surface water away from excavations, and establishing a protective cover over the disturbed areas and revegetating the areas as well. Disturbed portions of the site where the pipe is buried or where construction equipment has disturbed the ground surface should be seeded, then covered with straw or a rolled erosion control product, such as Curlex® excelsior blankets, following backfill placement. The Curlex® should be installed in accordance with the manufacturer's recommendations. Straw may be utilized in the relatively level area adjacent to the pond access road and the petroleum pipeline easement. Sloping portions of the site, or the area in close proximity to the stream, should be covered with Curlex®. Landslide Hazard Steep slopes along the proposed alignment include the relatively short section extending between the pond access road and the petroleum pipeline easement, and the ravine's south slope, along which the tightline will be installed. Slope stability is influenced by a number of conditions, including slope inclination, subsurface soil and groundwater conditions, and surface water drainage. Review of published geologic maps, conditions observed at the exploration locations, and surface observations have lead us to conclude that the site is primarily underlain at relatively shallow depths by glacially consolidated soils that are generally not subject to deep- seated instability. However, the near surface weathered soils, and fill materials, can be destabilized by unfavorable surface water conditions. Zipper Zeman Associates, Inc. 19231 36th Avenue West,Suite B201 Lynnwood,Washington 98036 (425)771 -3304 Proposed Sunnydale Downstream SIP J-686 Renton, Washington 10 May 2000 Page 10 Two adjacent rockery-like features comprising large rock placed on the slope adjacent to the detention pond, southwest of the upper control manhole as shown on Figure 2, were observed during the field exploration. The uppermost rockery extended approximately 25 to 50 feet along the future new buried pipe alignment, and was approximately 4 feet high. The lower rockery was approximately 8 feet away from the upper one, had a 12-foot width, and was about 6.5 feet high. Based upon our field measurements, it appears that the existing storm line from the manhole to the lower catch basin may be underneath the uppermost rockery. The rock feature, and surrounding areas, lacked evidence of recent instability or significant groundwater seepage. The City of Renton provided copies of two letters that addressed conditions leading to installation of the rock fill feature, as listed below: • Earth Consultants, Inc.; Site Reconnaissance, Slope Failure West of Lot 170, Sunnydale Mobile Home Park, Renton, Washington; E-1894-4, 28 December 1994; • Harza Consulting Engineers and Scientists; Sunnydale Mobile Home Park, Slope Erosion, Renton, Washington; File 7160G, 12 December 1994. The letters describe the authors' opinions regarding conditions leading to the formation of a relatively small landslide and/or erosional feature on the slope between the pond access road and the petroleum pipeline easement below, west of the storm sewer. Both authors reference some groundwater seepage from the exposed soils in the feature, and apparent flow of surface water from the pond over the steep slope. Both authors recommended similar repairs — filling the disturbed area with large rock or constructing rockeries. Based upon our review of the referenced letters, and conditions observed during the field exploration, we tend to agree with the conclusions presented in the Harza letter. We find it likely that the slope degradation was resultant from a combination of surface water flow over the steep slope combined with seepage from the underlying fill material. Deep-seated instability of the underlying glacially consolidated soils does not appear to have contributed to the distress. The rock fill repair appears to have been effective as well. Conditions observed at the location of our boring B-2, and observations noted in the referenced letters, confirmed the presence of fill material along the top of the slope separating the pond and the petroleum pipeline easement. The fill soils would be susceptible to erosion by flowing water, such as if the pond were to overflow, or if surface water were directed over the slope in a concentrated fashion. However, it is our opinion that the steep slope is unlikely to degrade due to instability of the underlying native glacially consolidated soils. The proposed surface alignment of the tightline on the south side of the ravine below the petroleum pipeline easement follows, or is in close proximity to, slopes with inclinations as steep as about 70 percent. Based upon our understanding of site conditions, it is our opinion that the proposed tightline alignment may be considered stable in regard to deep-seated instability. However, the steep slopes are characterized by a shallow weathered soil zone, up to about 3 feet Zipper Zeman Associates, Inc. 19231 36th Avenue West,Suite B201 Lynnwood,Washington 98036 (425)771 -3304 • Proposed Sunnydale Downstream SIP Yi.. J-686 Renton, Washington 10 May 2000 Page I 1 deep, that can be susceptible to downslope displacement in the form of slow creep, or more rapid movement, particularly during episodic storm events. The slow downslope soil displacement, referred to as solifluction, results in intermittent soil movement that can be evidenced by curved tree trunk growth, for example. That portion of the proposed tightline alignment between approximately Stations 4+50 and 5+50, as shown on Figure 2, is interpreted to susceptible to shallow soil creep. Two shallow depressions along the proposed tightline alignment are interpreted to have been subject to shallow displacement of the upper weathered soil horizon. The interval located between Stations 3+42 and 3+86 is interpreted as lacking the surficial weathered zone due to past shallow movement, most likely due to shallow soil saturation during a storm event, in our opinion . A second section between Stations 4+10 and 4+50 exhibits evidence of shallow downslope soil displacement. The root mass of a large fallen tree at this location suggests that displacement of the root mass initiated the soil movement, in our opinion. Future landsliding at the toe of the ravine slopes is likely, in our opinion, as the stream channel continues to erode soils in the streambed and channel sides. It is our opinion that erosion-induced landsliding along the channel would be manifested as high angle slump-type features resulting in oversteepened slopes along the channel. Upslope migration of such features is not likely to occur suddenly, in our opinion. Seismic Hazard A seismic hazard generally applies to an area that may experience distress due to soil strength loss during the cyclic earth movement associated with a seismic event. This soil strength loss phenomenon is referred to as liquefaction. Liquefaction is most commonly associated with loose and soft, relatively fine grained soils in combination with a high moisture content, typically in association with a shallow water table. It is our opinion that the glacially consolidated soils in the upland and ravine portions of the site would not be susceptible to significant strength loss due to liquefaction associated with a seismic event. The existing fill materials and colluvium disclosed by test pits TP-1 and TP-2 were relatively coarse and dense, and would not display significant soil strength loss during a seismic event, in our opinion. HDPE Tightline Considerations It is our understanding that current plans for the new surface tightline preclude utilizing the same alignment currently occupied by the 18-inch CMP. Use of an alternative alignment will allow eliminating installation of a structure and sharp turn in the alignment, avoiding the construction and maintenance problems exemplified by the current arrangement that employs a manhole constructed above the steam bed. Zipper Zeman Associates, Inc. 19231 36ih Avenue West,Suite B201 Lynnwood,Washington 98036 (425)771 -3304 Proposed Sunnydale Downstream SIP ' `: ' " J-686 Renton, Washington. ito" _ tgi10 May 2000 Page 12 The proposed surface tightline alignment as shown on Figure 2 generally reflects one that was field flagged during a site walk with representatives of the City of Renton and Entranco. The alignment was selected due to its combination of length, favorable slope conditions, and proximity to the existing alignment. It is our opinion that the alignment traverses terrain that is generally stable, and is not likely to be subject to deep-seated slope instability. The proposed alignment is also favorable in that it does not appear that substantial mechanical anchorage of the pipe is warranted. The pipe will have several fixed attachment points, including the catch basin on the downhill side of the petroleum pipeline easement, the lower buried section beginning about 150 feet upslope of the energy dissipator, and three sections between Station 3+42 and 4+10 where shallow burial is recommended. We recommend that two mechanical anchorage points be installed at approximately Stations 4+50 and 5-j.. We recommend that the mechanical anchorage consist of a 2-inch inside diameter, Schedule 80, galvanized steel pipe driven into the ground a minimum 8-foot distance on the downhill side of the tightline. The tip of the pipe may be flattened or equipped with a conical tip to facilitate achieving the recommended minimum embedment depth. We recommend that the pipes be driven with a jackhammer. We recommend that the tightline be regularly inspected after installation to verify that fallen trees, mass wasting, or vandalism have not adversely affected operation of the pipe. Several fallen trees of substantial size were observed within the ravine during our field visits. While we have found most HDPE pipe installations to hold up well under tree impact, regular inspection and maintenance is recommended. Utility Trenching and Backfilling The soils disclosed by the explorations can be excavated with conventional hydraulic excavation equipment, in our opinion, without exceptional difficulty. The soils disclosed by hand excavations along the surface tightline alignment can be excavated with normal hand tools, in our opinion. We recommend that utility trenching, installation, and backfilling conform to all applicable Federal, State, and local regulations such as WISHA and OSHA regulations for open excavations. In order to maintain the function of any existing utilities, we recommend that temporary excavations not encroach upon the bearing splay of existing utilities. The bearing splay of existing utilities should be considered to begin 3 feet away from the widest point of the pipe and extend downward at a 1H:1V slope. If, due to space constraints, an open excavation cannot be completed without encroaching on a utility, we recommend shoring the new utility excavation with a slip box or other suitable equipment. It appears that an open sided excavation will be required adjacent to the repaired slope failure near the upper manhole. We recommend that the existing rocks be carefully dismantled one by one, not mass excavated. Conditions should be carefully evaluated as the rocks are removed, as the existing CMP may be exposed during this process." The contractor should be Zipper Zeman Associates, Inc. 19231 36''Avenue West,Suite B201 Lynnwood,Washington 98036 (425)771 -3304 • Proposed Sunnydale Downstream SIP ..:�. J-686 Renton, Washington . �'' 10 May 2000 Page 13 prepared to address. leakage from the pipe, or seepage from the excavation, as the process proceeds. Reconstruction of this segment of the alignment is discussed subsequently. 1 We recommend that pipe subgrades be firm, unyielding and free of all soils that are loose, disturbed, or pumping. Such soils should be removed and replaced with compacted structural fill. After a firm subgrade has been established, we recommend that a minimum of 3 inches of bedding material be placed in the trench bottom if cobble or boulder size material is exposed. Otherwise, bedding for the HDPE pipe would not be necessary. Bedding material for plastic pipe should conform to Section 9-03.16 of the 2000 WSDOT Standard Specifications for Road, Bridge, and Municipal Construction (Publication M41-10). All trenches should be wide enough to allow for compaction around the haunches of the pipe. Otherwise, materials such as controlled density fill (CDF) or pea gravel could be used to eliminate the required compaction around the pipe. Backfilling the remainder of the trenches could be completed with soils excavated from the excavations if they can be compacted to the minimum levels recommended in the Structural Fill section of this report. Wet-of-optimum soils excavated from utility and structure excavations could only be used as backfill by reducing the moisture content to within a few percent of optimum. Limited test pit sidewall caving was observed during the field excavation. Contractors responsible for excavations should be prepared to provide adequate temporary shoring. Groundwater seepage was observed at the locations of test pits TP-1 and TP-2. The contractor should be prepared to adequately dewater excavations, allowing pipe and structure installation and backfill placement. We anticipate that sumps and pumps would be adequate for dewatering in the vicinity of the energy dissipator. The disassembled rockfill or rockery on the slope below the detention pond access road should be reconstructed in general accordance with the details shown on the Rockery/Rock Buttress Schematic, Figure 3. Some variation from these details may be necessary, depending upon conditions observed during construction. Provided that the slope protection can be installed with a finished height no taller than 8 feet, it may be constructed as a rockery. The rockery should be constructed of a sound, durable rock with a batter no steeper than 6H:1V. The bottom course of each rockery should be founded in at least medium dense or very stiff native soils. If the finished slope height is greater that 8 feet, we recommend that the slope be constructed as a rockery, but that a finished rock face surface with a 1.5H:IV inclination be constructed. The new HDPE pipe behind the rock facing should be placed upon a 3-inch minimum bedding thickness, as referenced above, in turn placed above 2 to 4-inch crushed rock quarry spalls (WSDOT 9-13.6) or shoulder ballast [WSDOT 9-03.9(2)]. The coarser crushed rock material should be utilized as backfill for the new trench behind the facing rocks, and be placed behind the facing rocks as they are installed. Zipper Zeman Associates,Inc. 19231 36"'Avenue West,Suite B201 Lynnwood,Washington 98036 (425)771 -3304 ' Proposed Sunnydale Downstream SIP '. '• "' J-686 Renton, Washington 10 May 2000 Page 14 Structural Fill All fill material placed in excavations for buried pipes and structures should be placed in accordance with the recommendations herein for structural fill. All structural fill should be generally free of organic material, debris, or other deleterious material. Individual particle size should generally be less than 6 inches in diameter. Structural fill should be placed in lifts no greater than 12 inches in loose thickness and each lift should be compacted to at least 90 percent of the modified Proctor maximum dry density as determined by the ASTM:D-1557 test procedure. We recommend that a geotechnical engineer, or his representative, be present during grading so that an adequate number of density tests may be conducted as structural fill placement occurs. In this way, the adequacy of the earthwork may be evaluated as it proceeds. The suitability of soils for structural fill use depends primarily on the gradation and moisture content of the soil when it is placed. As the amount of fines (that soil fraction passing the U.S. No. 200 sieve) increases, soil becomes increasingly sensitive to small changes in moisture content and adequate compaction becomes more difficult, or impossible, to achieve. Generally, soils containing more than about 5 percent fines by weight (based on that soil fraction passing the U.S. No. 4 sieve) cannot be compacted to a firm, non-yielding condition when the moisture content is more than a few percent from optimum. The optimum moisture content is that which yields the greatest soil density under a given compactive effort. At the time of the subsurface evaluation, some of the site soils disclosed by boring B-2, and test pits TP-1 and TP-2, generally had moisture contents above their optimum moisture content relative to their possible use as structural fill. However, soil moisture conditions should be expected to change throughout the year. Much of the site's native soil contains a significant fine-grained fraction. Re-use se of the on-site silt and silty fine sand soils disclosed by these explorations as structural fill will require that strict control of the moisture content be maintained during the grading process. Selective drying of over-optimum moisture soils may be achieved by scarifying or windrowing surficial materials during dry weather. Soils that are dry of optimum may be moistened through the application of water and thorough blending to facilitate a uniform moisture distribution in the soil prior to compaction. We recommend that the relic topsoil materials disclosed by test pits TP-1 and TP-2 be segregated from the mineral soil prior to re-using the excavated soils as backfill material. While not encountered in significant amounts at our exploration locations, deleterious debris in fill material may be present in close proximity to the detention pond access road. Debris materials should be segregated from the mineral soil and wasted from the site. Zipper Zeman Associates, Inc. 19231 3611'Avenue West,Suite B20I Lynnwood,Washington 98036 (425)771 -3304 Proposed Sunnydale Downstream SIP NWO fe °J� i r J-686 Renton, Washington 10 May 2000 Page 15 In the event that debris content, inclement weather, or wet site conditions prevent the use of on-site soil or non-select material as structural fill, we recommend that a "clean", free- draining pit-run sand and gravel be used. Such materials should generally contain less than 5 percent fines, based on that soil fraction passing the U.S. No. 4 sieve, and not contain discrete particles greater than 6 inches in diameter. Controlled Density Fill (CDF) would be a feasible alternative to compacted structural fill, and is most commonly used to backfill confined areas such as utility trenches. The use of CDF to backfill the trench crossing of the petroleum pipeline easement would facilitate that process and reduce the amount of time the trench remains open. It should be noted that the placement of structural fill is, in many cases, weather- dependent. Delays due to inclement weather are common, even when using select granular fill. We strongly recommend that subsurface utility work be scheduled for the drier months, if at all possible. We recommend that the site earthwork budget provide provisions for import granular fill material. Temporary and Permanent Cut Slopes Temporary slope stability is a function of many factors, including the following: 1. The presence and abundance of groundwater; 2. The type and density of the various soil strata; 3. The depth of cut; 4. Surcharge loadings adjacent to the excavation; ' 5. The length of time the excavation remains open. It is exceedingly difficult under the variable circumstances to pre-establish a safe and "maintenance-free" temporary cut slope angle. Therefore, it should be the responsibility of the contractor to maintain safe slope configurations since the contractor is continuously at the job site,able to observe the nature and condition of the cut slopes, and able to monitor the subsurface materials and groundwater conditions encountered. It may be necessary to drape temporary slopes with plastic or to otherwise protect the slopes from the elements and minimize sloughing and erosion. We do not recommend unshored vertical slopes or cuts deeper than 4 feet if worker access is necessary. The cuts should be adequately sloped or supported to prevent injury to personnel from local sloughing and spalling. The excavation should conform to applicable Federal, State, and local regulations. Based upon our review of WAC 296-155-650, Part N (Excavation, Trenching, and Shoring), we have interpreted the site soils disclosed by the explorations to meet the following type definitions: • Type A: Dense to very dense or hard, undisturbed glacial glacially consolidated soils with no groundwater seepage; • Type C: Existing fill, colluvium, loose to medium dense granular soils. Zipper Zeman Associates, Inc. 19231 36'1'Avenue West,Suite B201 Lynnwood,Washington 98036 (425)771 -3304 Proposed Sunnydale Downstream SIP J-686 Renton, Washington 10 May 2000 Page 16 Structure Foundation Recommendations Current plans call for constructing an energy dissipator adjacent to the stream channel at the bottom of the site. The structure will likely comprise a 72-inch pre-cast manhole with internal plumbing to allow water from the lower buried section of HDPE pipe to well upwards and flow over into the stream. We understand that the structure will require an excavation approximately 8 feet deep. Test pit TP-2 was excavated in close proximity to the proposed structure location. The test pit disclosed stiff to very stiff sandy silt with some gravel and interbedded sand, and medium dense gravelly sand to sandy gravel with some silt at the anticipated structure invert depth. These soils are adequate for support of the structure, in opinion. However, the sandy silt and silty sand soils would be easily disturbed when wet. We recommend that the excavation subgrade be mantled with a minimum 1-foot thickness of crushed rock shoulder ballast or quarry spalls as described for the rockery and rock buttress construction. The lift of coarse granular material will serve as a leveling course and working surface. In the event that debris, organic materials, or soft or loose material are encountered at structure subgrade elevation, we recommend that the material be removed and replaced with the shoulder ballast or quarry spalls. Site Disturbance Some of the native and fill soils that will be exposed during construction contain a significant percentage of fine-grained particles. Relatively clean sands are also present at or very near the ground surface. These soils are susceptible to disturbance, particularly when wet. We recommend that the contractor make every effort to minimize disturbance of stripped surfaces, and to limit site disturbance to those areas within the clearing and/or work limits. These efforts may include directing surface water away from open excavations, and utilization gravel-covered surfaces for construction equipment traffic and material storage. In addition, vehicle traffic over wet subgrades or prepared areas should be minimized. The steep slopes along the proposed surface tightline alignment would be susceptible to disturbance by tracked or wheeled construction equipment. We recommend that use of such equipment be prohibited during construction. Placement of the HDPE tightline utilizing winching techniques that preclude use of wheeled or tracked equipment on or in close proximity to the steep slopes is feasible, in our opinion. CLOSURE The conclusions and recommendations presented in this report are based on the explorations accomplished for this study. The number, location, and depth of the explorations for this study were completed within the site and scope constraints of the project so as to yield the information necessary to formulate our recommendations. Zipper Zeman Associates, Inc. 19231 36th Avenue West,Suite B201 Lynnwood,Washington 98036 (425)771 -3304 rz: . Proposed Sunnydale Downstream SIP Ls .a t' J-686 Renton, Washington 10 May 2000 Page 17 We recommend that Zipper Zeman Associates, Inc. be retained to provide geotechnical engineering services during the earthwork phases of the project in the event that the City of Renton requires assistance in this area. If variations in the subsurface conditions are observed at the time of construction, we would be able to provide additional geotechnical engineering recommendations to the contractor and design team in a timely manner as the project construction progresses. We appreciate this opportunity to be of service to you, and would be pleased to discuss the contents of this report or other aspects of the project with you at your convenience. Respectfully submitted, Zipper Zeman Associates, Inc. David C. Williams Associate n1. .' /-- John E. Zipper, P.E. Principal Enclosures: Figure 1 —Vicinity Map Figure 2=Site and Exploration Plan Figure 3 —Rockery/Rock Buttress Schematic Appendix A—Field Exploration Procedures and Logs Appendix B - Laboratory Testing Procedures and Results Distribution: Entranco (1) Zipper Zeman Associates,Inc. 1923 136''Avenue West,Suite B201 Lynnwood,Washington 98036 (425)771 -3304 • ipow-- reL-259 4PkW7 ..1r4 ."WI W inli,- . 7117 4-T,L I 1. f'\ i V •. 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PROJECT NO.J-686 PROPOSED SUNNYDALE SIP DATE:APRIL 2000 RENTON,WASHINGTON DESIGN:DCW GEOTECHNICAL AND ENVIRONMENTAL DRAWN BY:JPG SITE VICINITY MAP CONSULTING SCALE:UNKNOWN FIGURE 1 LEGEND 4--(44. 14. •B-1 Boring number and approximate location.Bonin: advanced utilizing conventional mechanical holl c�j v • stem auger drilling methods. _ Xh 110 HB-1 Hand boring number and approximate location. A Boring advanced utilizing hand tools. • h e r' ® TP-1 Test pit number and approximate location. • h i -AL ...,... 14 C,...„ .:.,1„ .1.- • . NI, 4,. i 0 . , Atilmhhe:. . .. . _•------ arr , , ..„-__ ,., ,,.. .- __fit cc-N), ,.iir 41111141t:111111114' /V. 7' ^-, 1/2111010+ 4:1 .. ,-7,, ,. • -,-„ ,..3-l2 1,..../il.:7.41000-,,, ,,,, ,,,,_4010- A _�� ?P-2 . _1 l • _ • -1-A- V(.65 / . • ./ • ALE • - PROJECT NO.J-686 PROPOSED ON WA HINNYD ON SIP J' DATE:APRIL 2000 i DESIGN:DCW 1TAL DRAWN BY:JPG SITE VICINITY MAP SCALE: 1"=40' FIGURE 2(PAGE 1 OF 2) Reference:Undated Preliminary Survey Data prepared by Entranco. • TOP Or PIPC IMO SOUP CIO I PVC UGIX PDX1,4 X , • A, , ..I h� � r ��► i - h � � Irmillow=ASEMENT jN L: 4� lr .--..," -, ;„- 0 ,Sto,,,.44 .... ...t . cu9i 4elifir .14iipf-i*P- t„,iiiiii,D A L E . ,„, ier. .:r ,i . . . w :If) 11 ..40,41ir . • - 10' SANITARY SEWER EASEMENT AF #8405110646 ..........4.7 . c . . . • ,� 300.000usi • i .• J . LEGEND B-1 Boring number and approximate la advanced utilizing conventional me stem auger drilling methods. ®HB-1 Hand boring number and approxirn Boring advanced utilizing hand toc ®TP-1 Test pit number and approximate 1( C. PROJECT NO.J-686 PROPOSED SUNNYDALE SIP DATE:APRIL 2000 RENTON,WASHINGTON DESIGN:DCW \1TAL DRAWN BY:JPG SITE VICINITY MAP SCALE: 1"=40' FIGURE 2(PAGE 2 OF 2) • ' ROCKERY/ROCK BUTTRESS SCHEMATIC- NOT TO SCALE CR FLATTER) SOUND, DURABLE 1 [---- • " - o. NON-WEATHERED ROCK , •:•` 1 TO 2 ' , ....... •; MIN •:. ••...� .. 16 IN. •~FREE-DRAINING BACKFILL .. ���lll"' ' (MAX. 5% FINES); MIN.3.5 . i ' WIDE LAYER OF 2"-4" •' QUARRY SPALLS • • •• ADJACENT TO ..• '• ROCKERY • 6 HEIGHT t' (MAX. 81 • .. .+' • .' • f ' • •• . . 18-INCH INSIDE DIAMETER •''• ,' '• HOPE TIGHTLINE • MINIMUM , �� WIDTH (FT) ;• = HEIGHT/3 , MIN. 12" •.. • " • 7T _ • • L.• . 1 • . FIRM. UNDISTURBED SOIL NOTES: . ROCK SHALL BE SOUND AND HAVE A MINIMUM DENSITY OF 160 POUNDS PER CUBIC FOOT. , THE LONG DIMENSION OF ALL ROCKS SHALL BE PLACED PERPENDICULAR TO THE WALL EACH ROCK SHALL BEAR ON TWO ROCKS IN THE TIER BELOW. - ' ROCKERIES ARE EROSION-CONTROL STRUCTURES. NOT RETAINING WALLS. NATIVE MATERIAL MUST BE STABLE AND FREE-STANDING IN CUT FACE. • FOR HEIGHTS GREATER THAN 8 FEET,FACING ROCK MAY BE STACKED IN FRONT WITH A 1.5H:IV INCLINATION LOCATION OF ROCKERY OR BUTTRESS RELATIVE TO TIGHTLINE SHOULD BE FIELD-FIT ZIPPER ZEMAN ASSOCIATES,INC. PROJECT NO. J-686 PROPOS SUNN SIP DATE: APRIL2000 RENTON ED,WASHINGTONYDALE DESIGN: DCW GEOTECHNICAL AND ENVIRONMENTAL DRAWN BY: DCW ROCKERY/ROCK BUTTRESS SCHEMATIC CONSULTING SCALE: N.T.S. FIGURE 3 - • 04 4p7? APPENDIX A FIELD EXPLORATION PROCEDURES AND LOGS •. . D AFC APPENDIX A FIELD EXPLORATION PROCEDURES AND LOGS J-686 Our field exploration for this project included two test pits (TP-1, TP-2) excavated on 21 March 2000, and two borings (B-1, B-2) and four hand borings (HB-1 through HB- 4) advanced on 24 March 2000. Approximate exploration locations are shown on the Site and Exploration Plan, Figure 2. Exploration locations were determined by measuring distances from existing site features with a fiberglass tape relative to an undated topographic map of the site provided by Entranco As such, the exploration locations should be considered accurate to the degree implied by the measurement method. The approximate ground surface elevation at each exploration location was determined by interpolating the information provided on the topographic plan, or via hand level methods relative to specific surveyed site features, such as manholes. The following sections describe our procedures associated with the exploration. Descriptive logs of the explorations are enclosed in this appendix. Soil Boring Procedures Our exploratory borings were advanced with a hollow stem auger, using a portable drill rig operated by an independent drilling firm working under subcontract to our firm. A geotechnical engineer from our firm continuously observed the borings, logged the subsurface conditions encountered, and obtained representative soil samples. All samples were stored in moisture-tight containers and transported to our laboratory for further visual classification and testing. After each boring was completed, the borehole was backfilled. Throughout the drilling operation, soil samples were obtained at 2.5- to 5-foot depth intervals by means of the Standard Penetration Test (ASTM: D-1586). This testing and sampling procedure consists of driving a standard 2-inch outside diameter steel split spoon sampler 18 inches into the soil with a 140-pound hammer free falling 30 inches. The number of blows required to drive the sampler through each 6-inch interval is recorded, and the total number of blows struck during the final 12 inches is recorded as the Standard Penetration'Resistance, or"blow count" (N value). If a total of 50 blows is struck within any 6-inch interval, the driving is stopped and the blow count is recorded as 50 blows for the actual penetration distance. The resulting Standard Penetration Resistance values indicate the relative density of granular soils and the relative consistency of cohesive soils. The enclosed boring logs describe the vertical sequence of soils and materials encountered in each boring, based primarily upon our field classifications and supported by our subsequent.laboratory examination and testing. Where a soil contact was observed to be gradational, our logs indicate the average contact depth. Where a soil type changed DDAF between sample intervals, we inferred the contact depth. Our logs also graphically indicate the blow count, sample type, sample number, and approximate depth of each soil sample obtained from the borings, as well as any laboratory tests performed on these soil samples. If any groundwater was encountered. in a borehole, the approximate groundwater depth, and date of observation, is depicted on the log. Groundwater depth estimates are typically based on the moisture content of soil samples, the wetted portion of the drilling rods, the water level measured in the borehole after the auger has been extracted, or through the use of an observation well. Hand Boring Procedures Four hand borings (HB-1 through HB-4) were advanced at the approximate locations shown on the Site and Exploration Plan, Figure 2. An engineering geologist from our firm advanced an approximately 8-inch diameter boring by hand using a post- hole digger, continuously observing the soil cuttings as they were retrieved. Representative portions of the soils retrieved were placed in moisture tight containers and returned to our laboratory for further visual classification and testing. Logs of the hand borings are included in this appendix. Test Pit Explorations An independent contractor working under subcontract to our firm excavated the test pits through the use of a small trackhoe. An engineering geologist from our firm continuously observed the test pit excavations, logged the subsurface conditions, and obtained representative soil samples. The samples were stored in moisture tight containers and transported to our laboratory for further visual classification and testing. After we logged each test pit, the,operator backfilled each with excavated soils tamped into place. Some settlement of the backfill should be expected over time. The enclosed test pit logs indicate the vertical sequence of soils and materials encountered in each test pit, based primarily on our field classifications and supported by our subsequent laboratory testing. Where a soil contact was observed to be gradational or undulating, our logs indicate the average contact depth. We estimated the relative density and consistency of in situ soils by means of the excavation characteristics and by the sidewall stability. Our logs also indicate the approximate depths of any sidewall caving or groundwater seepage observed in the test pits, as well as all sample numbers and sampling locations. ZIPPER ZEMAN ASSOCIATES, INC. A 19231 36TH Ave.W.Suite B201,Lynnwood,Washington 98036vJ �ni Fr • Hand Boring HB-1 Project: Sunnydale SIP Location: Tightline STA 1+30,see Figure 1 Project No:J-686 Approximate ground surface elevation(feet): 220 Date Drilled:24 March 2000 Depth Material Description Sample Nc %M Testing (ft) 2±inches ORGANIC FOREST DUFF above loose,wet,brown, gravelly SAND with trace silt and some roots 1 Loose,wet,brown,silty SAND with trace gravel S-1 22 2 Medium stiff,wet,brown with orange mottling,sandy SILT with 3 trace fine and fibrous organic material Stiff to very stiff,wet,brown,sandy SILT 4 Total depth=3.8 feet • 5 No caving,slight seepage at 2.7 feet ZIPPER ZEMAN ASSOCIATES, INC. 19231 36T11 Ave.W.Suite B201,Lynnwood,Washington 98036 DpAF L� Hand Boring HB-2 Project: Sunnydale SIP Location: Tightline STA 2+55,see Figure 1 Project No: J-686 Approximate ground surface elevation(feet): 196 Date Drilled:24 March 2000 Depth Material Description Sample Nc %M Testing (ft) 4±ORGANIC FOREST DUFF and soft,damp,dark brown,sandy SILT with fine organic material(Topsoil)above soft,wet,brown, 1 SILT with some sand and fine to medium roots 2 Medium dense,moist,brown with some gray mottling,fine SAND with trace fine to coarse gravel 3 S-1 21 • Total depth=4 feet 5 No seepage or caving observed ZIPPER ZEMAN ASSOCIATES, INC. A 19231 36T"Ave.W.Suite B201,Lynnwood,Washington 98036 i) F Lir • Hand Auger HB-3 Project: Sunnydale SIP Location: Tightline STA 3+65,see Figure 1 Project No: J-686 Approximate ground surface elevation(feet): 178 Date Drilled: 24 March 2000 Depth Material Description Sample Nc %M Testing (ft) 3 ±ORGANIC FOREST DUFF and soft,damp,dark brown,sandy SILT with fine organic material(Topsoil)above loose to medium dense(at 2 feet),moist to wet,brown,gravelly SAND with trace to some silt,occasional cobbles to 5-inch diameter 2 S-1 8 3 4 , . Total depth=3.8 feet 5 No seepage or caving observed ZIPPER ZEMAN ASSOCIATES, INC. 19231 36"1 Ave.W.Suite B201,Lynnwood,Washington 98036 DRAF , Hand Boring HB-4 Project: Sunnydale SIP Location: Tightline STA 4+22 see Figure 1 Project No: J-686 Approximate ground surface elevation (feet): 172 Date Drilled: 24 March 2000 Depth Material Description Sample Nc %M Testing (ft) 3±ORGANIC FOREST DUFF and soft,damp,dark brown,sandy SILT with fine organic material(Topsoil)above loose,wet,brown, silty,fine SAND with some fine roots 2 . Dense,wet,brown,fine SAND with trace silt 3 S-1 28 4 ' • Total depth=.4 feet 5 No seepage or caving observed iLEF1 Depth(feet) Material Description Sample • No. TP-1 0.0-3.0 Surface brush atop loose to medium dense(at 2 feet),moist,dark brown/gray, silty S-1, S-2 gravelly SAND with some angular gravel,cobbles, roots and organics(fill). 3.0—6.0 Medium dense,moist,tan-brown,gravelly SAND with some silt(probable fill). S-3 6.0—6.5 Relic topsoil. 6.5—8.0 Stiff to very stiff,moist-wet,mottled brown/gray,sandy SILT with some gravel and S-4 interbedded silty SAND. 8.0— 11.0 Medium dense,wet,gray,silty SAND with some gravel and interbedded sandy S-5 SILT. Test pit terminated at 11.0-feet on 3/21/00. Location of boring approximately 30-feet west and 10-feet south of outfall. Slow seepage observed at 9.5-feet. No caving observed. Note: Adjacent creek grade approximately 6-feet below test pit surface grade. Ground surface elevation= 103 feet Depth(feet) Material Description Sample No. TP-2 0.0-3.0 Surface brush atop loose to medium dense,moist,tan-brown,gravelly SAND with S-1, S-2 some silt(fill). 3.0—3.5 Relic topsoil. 3.5—6.0 Soft to medium stiff,moist-wet,dark brown/gray/black,sandy SILT with some S-3 organics,and trace gravel. 6.0—8.0 Stiff to very stiff,moist-wet,mottled brown/gray,sandy SILT with some gravel and S-4 interbedded silty SAND. 8.0— 10.0 Medium dense,saturated,brown,gravelly SAND to sandy gravel with some silt. S-5 Test pit terminated at 10.0-feet on 3/21/00. Location of boring approximately 100-feet west and 10-feet south of outfal I. Rapid seepage observed at 8-feet. Moderate caving observed below 6-feet. Note: Adjacent creek grade approximately 4.5-feet below test pit surface grade. Ground surface elevation=90 feet [ AFLJ Pr.o.UJEc.is Sunnydale Downhill SIP JOB NO.. J-686 BORING B-1 PAGE 1 OF 1 Location: Renton,WA Approximate Elevation: 289 feet Soil Description o Penetration Resistance en . ' aQ as C ;; A A o, c co d COC I- E E o m Standard Blows per foot Other HSI U) co Z O Z t- o 10 20 30 40 50 Hard(?),moist,brown,fine to coarse gravelly SILT S-1 I ; _�with some sand and organics(blow count may be I 1 I -• 1 I 40/9" overstated) ; I I 7 — Stiff,moist,brown,gravelly SILT with some sand - I 1 1 I I T I• 1 I I I I 1 I• • I I I I 1 11 Loose to medium dense,moist,brown,fine SAND S-2a I I I I — \ with trace to some silt 1 I ' 1 I 10. I I I • S-2b 1' I ,1 I I I I I I I`• I , I I I - ss -- I I I I I I 1 I I ,'I I I I 5 1 1 I I' I 1 I ' — Stiff to hard,moist,brown,SILT with occasional - g_3 I , ' A - - II ' ' • 22 interbedded fine sand ----- I 1 •i I I I 1 I I 1 I 1 I I 1 I I I 1 I • I 1 I I I ' I I I 1 1 1 I I I • I 1 I I , . - • -----_____--- I I I 1 I Y I I 1 I I I I OA I I I 31 S 4 I I I r, I • I I - ___ ____ I I I ' ' 1 I •, I I I ' I 1I •l 10 I I I Grading to SILT with some fine sand S-5 ' ' �' A. 48 1 1 1 I 1 I I I I I I I 1 I I I 1 I I ' I I I I I I I _ Total depth=11.5 feet. 1 1 1 1 L No groundwater observed. 1 1 1 J L 1 L _____ ---------- I I I 1 I I I I 1 I -I L I 1 L I . I I I I I I I 1 I I I 1 I 1 I 1 1 I 15 _-__- I L I -1L --- I 1 L I --- I I I I I I I I I I I I I I I I I I • _• I 1 I J L I 1 L I • -~~---..-___ I 1 I I I I ' I I 1 I I I I I I 1 I -1 L 1 4 L I I I I I I 1 I I 1 I I I I I I I I ' 1 I I I I I 1 1 I I I I 1 I I I ' I I I 1 20 ' 1 I I I I 1 I I I 1 I I I 1 1 I I — I I I I 1 1 I I I III I 1 'I I I 1 I I 1 I I 1 1 I I I I I 1 I .1 I I I . _ -I- --I--. • I I 1 I ' I I I 1 1 I I I ' I I I 1 I I I I I I I I I I 1 I I I I I I 25 • Explanation o 10 20 .30 40 50 • I2-inch O.D.split spoon sample Lab Testing Legend Moisture Content 1 3-inch I.D Shelby tube sample ATT Atterberg Limit Plastic Limit Natural Liquid Limit ® No Recovery GSA Grain Size Analysis V Groundwater level at time of drilling MC% Moisture Content >50% ATD or date of measurement I Zipper Zeman Associates,Inc. BORING LOG Figure A-1 Geotechnical&Environmental Consultants Date Drilled: 3/24/00 Logged By: Eric Lim _ D N. A P "...---1 PROJECT: Sunnydale Downhill SIP JOB NO. J-686 BORING B-2 PAGE 1 OF 1 Location: Renton,WA • - Approximate Elevation: 312 feet _ Soil Description Penetration Resistance w Z. s asa C g; A A m rn c E Eo f° Standard Blows per foot Other j n o Cl) ~ U) Z 0 Z 1- 0 10 20 30 40 50 Medium dense,moist,dark brown,gravelly silty, S-1 ' SAND and sandy GRAVEL with some silt(fill) I 12 i 1 r I 1 S-2 ; ; 4 : ' 15 GSA I ' I I I I I I ' I 1 I ^^ --- ---- ,I I I I I I I I 1 5 I ' I I I I 1 --- ---- S 3 I I I I I I I • 11 GSA — I. I I 1 I 1 I I I` I 1 I I I I I , I I I I I I ' I I I I I• I I 1 , I I 1 1 I I I — 1 , I I I 1 I I .I 14 1 1 I 1 I I 12 S 4 1 I 1 I I , I I I I I I I .1 • 10 1 I. I , S_5 1 1* I , I 16 GSA I I' I I 1 1, I 1 1 1• 1 I I I 1: I I 1 I I I 1 1• 1 , J — - I I I' 1 I I I S-6 : A ' 1 : 16 GSA — I I 1 I 1 I I I � I .I I I I I _1__1__ - I I . I I :I I . I 1 15 _1�_I__J__ L _ _I_ _J _ _I_ _ _I__. S-7 12 • I 1 1 1 I • 1 ‘1 J L 1 J L I . 14 1 1 1 1 1 1 I I 1 1 1 1 1 Very stiff,moist,blue-gray SILT. - I I I I 1 I I I I , 1 1 I • I I I I I I — • I I I •I 1 I I I I 1 I '1 I I I I I - - -I--�'- -I--�',- — ------------ 1 1 I . 1 1 I I 1 I I I I I I 1 I 20 U -- -I +- -.I- - -I- - - - - -I-- --1 -- --- S V I I I 1 : I I 1 23 I I I I I I 1 — 1 I I I I I I 1 I I I I I I 1 I I — Total depth=21.5 feet. ___________ + r No groundwater observed. 1 : : : I : : 1 1 1 I 1 I 1 — I I I I I I I I I 11 1 1 1 1 1 • I I I I I I I I 1 1 I I I I 1 25 Explanation o .10 20 30 40 50 I12-inch O.D.split spoon sample Lab Testing Legend Moisture Content II3-inch I.D Shelby tube sample ATT Atterberg Limit Plastic Limit Natural Liquid Limit ® No Recovery GSA Grain Size Analysis I • V Groundwater level at time of drilling MC% Moisture Content >50% ATD or date of measurement Zipper Zeman Associates,Inc. BORING LOG .— Figure A-2 Geotechnical&Environmental Consultants Date Drilled: 3/24/00 Logged By: Eric Lim DRAF " APPENDIX B LABORATORY TESTING PROCEDURES AND RESULTS mApar APPENDIX B J-686 LABORATORY TESTING PROCEDURES A series of laboratory tests were performed during the course of the this study to evaluate the index and geotechnical engineering properties of the subsurface soils. Descriptions of the types of tests performed are given below. Visual Classification Samples recovered from the exploration locations were visually classified in the field during the exploration program. Representative portions of the samples were carefully packaged in moisture tight containers and transported to our laboratory where the field classifications were verified or modified as required. Visual classification was generally done in accordance with the Unified Soil Classification System. Visual soil classification includes evaluation of color, relative moisture content, soil type based upon grain size, and accessory soil types included in the sample. Soil classifications are presented on the exploration logs in Appendix A. Moisture Content Determinations • Moisture content determinations were performed on representative samples obtained from the exploration in order to aid in identification and correlation of soil types. The determinations were made in general accordance with the test procedures described in ASTM: D-2216. The results are shown on the exploration logs in Appendix A. . Grain Size Analysis A grain size analysis indicates the range in diameter of soil particles included in a particular sample. Grain size analyses were performed on representative samples in general accordance with ASTM: D-2487. The results of the grain size determinations for the samples were used in classification of the soils, and are presented in this appendix. ,a . DR) A.F .,_, GRAIN SIZE DISTRIBUTION ASTM D422 SIZE OF OPENING IN INCHES — U.S.STANDARD SIEVE SIZE HYDROMETER • 36' 12' I 3' 1 UT314' 3/3' i 10 20 40 60 1i 0 200 100 1 I 1 90 ' = 80 - .._ . _ — _ 0 _ LU 70 _ . }. CO — W 60 H z _ Li Z 50— Ui • — U W40 . — — , a 30— 20 10--, I \IN.______„_____4! I I i' 0 ,, i . l II I 1 I 1000.00 100.00 10.00 1.00 0.10 0.01 0.00 GRAIN SIZE IN MILLIMETERS Coarse Fine Coarse Medium Fine Silt Clay BOULDERS COBBLES GRAVEL SAND FINE GRAINED Exploration Sample Depth (feet) Moisture(%) Fines (%) Description B-2 S-2, 3, 5, 6 2.5-12.5' 6 5 Sandy GRAVEL with some silt ZIPPER ZEMAN ASSOCIATES, INC PROJECT NO: J-686' PROJECT NAME: DATE OF TESTING: 3/27/00 Sunnydale GEOTECHNICAL AND ENVIRONMENTAL CONSULTING .4 APPENDIX B Project Location Sheets APPENDIX B Project Location Sheets • J IV NE 12TH ST o f' Cg'tri� NE I P PRE aR `'� Z z M Q� 900 yJN�SE rNE M ¢ ^a 2 g- 0 w Z 900 NE 10TH S / SE y . m a =� = Z SE h TH 'A irt z N 8T11 ST z W to NE-NE- NE N = _ = x > 7tH sZ z w T Uii IPAU) w O_ > I. CC ¢ ¢ N 6TH ST W Zo < 0J re z o a � / y m N 4TH ST q NE 4TH ST kyqpA©rI ' itiviAli' O SS 3R +- _9��` to MOBILE HOME P PARK a 1e1e.® ti SE 5TH ST r z rim r �� cT .� ��STPROJECT 711- "Ii. 4111%'.114111W a��` LOCATION .i �PSGiliiis.,:::: *.9„- �DAR s, RFiTO� G ,I U NpTON N. t69 SE i g `'' �qr 0 Z O� � ..74, a `PUGET S o 0 z 0 0 0 ^ La TITLE: PROPOSED WORK: Sunnydale Downstream Replace existing damaged pipe, Storm System Replacement Project structures, and eroding outfall with ADJACENT PROPERTY OWNERS: new pipe, improved alignment and DIRECTIONS TO SITE: outfall location, and energy Take 1-405 South to Maple Valley King County dissipator. Hwy. (SR169), East on SR169 to SHEET TITLE: VICINITY MAP AT: Township 23N, Range 5E SE 5th. A maintenance access SCALE: NOT TO SCALE Section 16 road to the site is located just SHEET: 1 of 3 "' west of SE 5th. a+ ASSISTANCE BY: Entranco 3 DATE: May 2000 04s4 DATUM: City of Renton DRAWN BY: GLS 44 - — �- — - — ___ ---_ • t vex I-- w 00 9 o U cn tr F-- Z w O Z >- w Ln W z p Y F- p H w p O W 4/ w01- 1- ZQJin d' w O t- Q 00 d w 0' m U O_ � DW N OLYMPI. .. . • —� ELINE EASEMENT J w (BASED ON R/W M. w oo ��ED W/ STATE P.N.R.) z Q x - • o m 1/16TH LINE ` . c9 N 01'04'1 1 " E (170.21 ' DEED) z m -- p BP A. EASEMENT N - I ! !wz - piw w ` -iSI- z F- gyp r Jpz . -- N !oIRL O�E pZ. NO :. �TN EI: a zwz o_ WRP I0 1 EDRpN UU • DR0 `4 SEN6 :. E 05 Co o 18502 I ::: o w o Z o_ > Z • CO co w o ....... LLI 8-- 8 — ix - 0 x w w 0 ------------\ ENa „-w W _ �d M� 03 WO 00• U w X.o Z (0 k p U) , Is-- l iJ x wpw0I- Q O - , `n. Id CD 1--cn cn I I, I O ' LiW • o . k, MATCHLINE PAGE 3 PROJECT TITLE: PROPOSED WORK: Sunnydale Downstream Replace existing damaged pipe, ' Storm System Replacement Project structures, and eroding outfall with ' ADJACENT PROPERTY OWNERS: new pipe, improved alignment and ' DIRECTIONS TO SITE: outfall location, and energy Take 1-405 South to Maple Valley King County dissipator. Hwy. (SR169), East on SR169 to SHEET TITLE: PLAN SHEET 2 AT: Township 23N, Range 5E SE 5th. A maintenance access SCALE: NOT TO SCALE Section 16 road to the site is located just west of SE 5th. SHEET: 2 of 3 ASSISTANCE BY: Entranco DATE: May 2000 DATUM: City of Renton DRAWN BY: GLS 1 .A s w MATCHLINE PAGE 2 z j F- CD ` r- p O r .n O ate, . . . ..�..; '. oo o . ' CO W `'.� o. ... e'fx . . . LLI o S6._ w y.d' t- a 0 I w >-J 1 , z w ! v`.. o a . . a oa F- CC E m a a a 0 u) o ce w . . PROJECT TITLE: PROPOSED WORK: Sunnydale Downstream DATUM: City of Renton Replace existing damaged pipe, Storm System Replacement Project structures, and eroding outfall with ADJACENT PROPERTY OWNERS: new pipe, improved alignment and DIRECTIONS TO SITE: outfall location, and energy Take 1-405 South to Maple Valley • King County dissipotor. Hwy. (SR169), East on SR169 to SHEET TITLE: PLAN VIEW 3 AT: Township 23N. Range 5E SE 5th. A maintenance access SCALE: NOT TO SCALE Section 16 road to the site is located just SHEET: 3 of 3 west of SE 5th. ASSISTANCE BY: Entranco DRAWN BY: GLS DATE: May 2000 EXHIBIT B tau -u / t CITY OF RENTON DEVELOPMENT SERVICES DIVISION • MASTER APPLICATION OWNER(g): ON"(cont) PROJECT:INFORIVIATI Note: If there is more thin on legal owner,please attach an additional notarized. EXISTING LAND USE(S): Master application to.each owner.' ' STORM DRAIN PIPE NAME: L� i' ADDRESS: ?O tih)4 (J g �' � PROPOSED LAND USE(S): City: I K 1 ]A J ZIP: cmia STORM DRAIN PIPE TELEPHONE NUMBER: — aj f_ _ ') _ aoa 'GONTAGT;PERSONfAPPLICANT EXISTING COMPREHENSIVE PLAN MAP DESIGNATION: RESIDENTIAL RURAL NAME: Allen Quynn,City of Renton, Utility Systems Div. Surface Water Utility Section PROPOSED COMPREHENSIVE PLAN MAP DESIGNATION: ADDRESS: 1055 South Grady Way N/A EXISTING ZONING: city: Renton ZIP: 98055 RC—RESOURCE CONSERVATION TELEPHONE NUMBER: 425-43 0-7247 PROPOSED ZONING: :.::::PR.OJECT:INFORMATION SITE AREA(SQ.FT.OR ACREAGE): PROJECT OR DEVELOPMENT NAME: THE PROPOSED PIPELINE WILL COVER AN AREA SUNNYDALE DOWNSTREAM STORM SYSTEM APPROXIMATELY .03 ACRES. REPLACEMENT PROJECT PROJECT VALUE: $150,000.00 PROPERTY/PROJECT/ADDRESS(S)/LOCATION: IS THE SITE LOCATED IN THE AQUIFER PROTECTION AREA? SEE LEGAL DESCRIPTION. NO KING COUNTY ASSESSOR'S ACCOUNT NUMBER: SEE ATTACHED IS THE SITE LOCATED IN ANY OTHER TYPE OF ENVIRONMENTALLY SENSITIVE AREA? SEE ATTACHED"PROPERTY IDENTIFICATION YES, THE SITE OR PORTIONS OF THE SITE HAVE LISTING". BEEN CLASSIFIED AS WITHIN THE SENSITIVE -AREAS: STEEP SLOPES, SEISMIC, SLIDES, EROSION AND STREAMS. H:\DIVISION.S\UTILITIE.S\DOCS\2000-237.doc\a. 1 LEGAL DESCRIPTION OF PROPERTY (Attach separate sheet if needed) The project is located in the SE quarter(1/4) of Section 16,Township 23N, Range 5E.The upper end of the project is at the Southeast corner of the Sunnydale Mobile Home Park. The lower end of the project is near the intersection of SE 5th Street and Newport Ave. SE,North of Maple Valley Hwy. The City has three existing drainage easements within the project limits(see attached easement legal descriptions). Two of the easements are with King County and are designated Easement"A" and Easement"B". The third easement is with the Estate of John C.Edwards,the Estate of Anna G.McMahon and the Rainier Sand and Gravel, Inc. The property is now under the ownership of LA Pianta LLC. - ..:. : ':: .: ' :-TYPE.OF.APPIlICATTON_&FEES: '` : .._: ees: :: ;::., :. . :_: :. . Checkl;application types that a 1 Cz staff::will etermuie _ANNEXATION $ SUBDIVISION _REZONE $ — SPECIAL PERMIT $ _LOT LINE ADJUSTMENT $ _TEMPORARY PERMIT $ _SHORT PLAT $ _CONDITIONAL USE PERMIT $ _TENTATIVE PLAT $ _SITE PLAN APPROVAL $ _PRELIMINARY PLAT $ _GRADE&FILL PERMIT $ _FINAL PLAT $ (No.Cu.Yds: ) X VARIANCE $ (from Section:4-4-130) $ 250.00 PLANNED UNIT DEVELOPMENT $ _WAIVER $ _PRELIMINARY _ROUTINE VEGETATION _FINAL MANAGEMENT PERMIT $ _BINDING SITE PLAN MOBILE HOME PARKS $ SHORELINE REVIEWS: _SUBSTANTIAL DEVELOPMENT $ _CONDITIONAL USE $ _VARIANCE $ _EXEMPTION $ X ENVIRONMENTAL REVIEW $ 1,000.00 REVISION AFFIDAVIT OF OWNERSHIP `;. . I,(Print Name) I^il.PaK Pt.„SE 6ALE ,declare that I am(please check one) _the owner of the property involved in this application, x the authorized representative to act for the property owner(please attach proof of authorization),and that the foregoing statements and answers herein contained and the information herewith are in all respects true and correct to the best of my knowledge and belief. I certify that I know or have satisfactory evidence that /'ia'r- A • signed !1 � � '' '' /�L �• ' L.1\4 . this instrument and acknowledged it to be his/ 3eir free and volunuryAcl�is I + I I "' ' , purposes mentioned in the ins ment • .0. . (Name o Owner/Represe flue) Notary Public in and for the State of W. 1:ton\. 0 J :V _� to Notary(Print) S A • (Signature o M44 ✓ // 05 f Owner/Ree rese ati,ve�)) My appointment expires: `-� , ?.i O q ' t. ICE , Grp H:\DI VISION.S\UTILITIE.S\DOCS\2000-237.doc\a (THIS SECTION TO BE COMPLETED BY CITY STAFF.) City File Number: ECF SA R SHPL CU LLA PP FP TP SP RVMP V AAD W FPUD SM SME MHP: BSP A CPA TOTAL FEES: $. • TOTAL POSTAGE PROVIDED:$ H:\DIVISION.S\UTILITIE.S\DOCS\2000-237.doc\a 05/23/2000 13:32 217b47buipb ,. , -•,• . -- - rlHT—e4—Gbbiel 10:06 CITY OF RENTON PBPW 425 430 7241 P.02/03 . :. •CITY*OF:RENTON •DEVELOPMENT.SERVICES DIVISION'. .• • .•MASTER:APPLICATION • .. .. . :... . ... .... :-. ;;� � :..PIZ.OJ�EC`F�INP��VS�,TION.(coin), .: Note: Ifinere LS rtioie>t>ian On Iegel 64r1:44 picric 81taelr aIt edititlona1 noterizlfd EXISTING LAND USE(S): • iyaster.appiic ton to•each awru:r: - STORM DRAIN PIPE NAME: /` ✓N CUI1U. . ADDRESS: ZY SOO Lf JCi - PROPOSED LAND USE(S): City: C, e ,C_ (A)A zw• C \OLI STORM DRAIN PIPE TELEPHONE NUMBER:• EXISTING COMPREHENSIVE.•CQN'T1�C3'.FERSQNI.�'PLICANT:" :• :: PLAN MAP DESIGNATION: RESIDENTIAL RURAL NAME: Allen Quynn,City of Renton, • Utility Systems Div. Surface Water Utility Section PROPOSED COMPREHENSIVE.PLAN MAP DESIGNATION: ADDRESS: 1055 South Grady Way N/A EXISTING ZONING: City: Renton ZIP: 98055 Rc—RESOURCE CONSERVATION TELEPHONE NUMBER: . 425-430-7247 PROPOSED ZONING: _ ^ -="� N/A PROJECT III ORMATION;'• SITE AREA(SQ.PT,OR ACREAGE): PROJECT OR DEVELOPMENT NAME: THE PROPOSED PIPELINE WILL COVER AN AREA APPROXIMATELY.03 ACRES. SUNNYDALE DOWNSTREAM STORM SYSTEM REPLACEMENT PROJECT PROJECT VALUE_ - $150,000.00 PROPERTY/PROJECT/ADDRESS(S)/LOCATION: IS THE SITE LOCATED IN THE AQUIFER PROTECTION AREA? SEE LEGAL DESCRIPTION. NO `KING COUNTY ASSESSOR'S ACCOUNT NUMBER:. SEE ATTACHED IS THE SITE LOCATED IN ANY OTHER TYPE OF ENVIRONMENTALLY SENSITIVE AREA? SEE ATTACHED"PROPERTY IDENTIFICATION YES,THE SITE OR PORTIONS OF THE SITE HAVE LISTING". BEEN CLASSIFIED AS WITHIN THE SENSITIVE AREAS: STEEP SLOPES, SEISMIC,SLIDES, EROSION AND STREAMS. a of Post-it-0 Fax Note 7671 Date 1pegee� To I0.44. u' ✓\ From 11 a Q.0 S� Co/Dept. Co. (�e ,[ vwt V 1_ S L Phone# - Phone a H:�DIVISION SUTIILITIE.S\DOCS120 0 0-23 7.doC1a +� ry Fax Fax M J l.� 6 � �` � 05/23/2000 13:32 206231D1lyb MAY-24-2000 10:06 CITY OF RENTON PBPW 425 430 7241 P.03/03 LEGAL:DESCRIPTION OF PROPERTY (Attach separate sheet if needed) •The project is located in the SE quarter(1/4)of Section 16,Township 23N,Range 5E.The upper end of the project is at the Southeast corner of the Sunnydale Mobile Home Park. The lower end of the project is near the intersection of SE 5th Street and Newport Ave. SE,North of Maple Valley Hwy. The City has three existing drainage easements within the project limits(see attached easement legal descriptions). Two of the easements are with King County and are designated Easement"A"and Easement"B". The third easement is with the Estate of John C.Edwards,the Estate of Anna G.McMahon and the Rainier Sand and Gravel,Inc. The property is now under the ownership of LA Pianta LLC. . TYPE.OF. PLICATIQN:&.FEES • . • • • . . • . • 'Clieck all.application'.types t a 1/311,--•City.s.taff-wil•l.determine fees.. • ANNEXATION $ SUBDIVISION REZONE $ SPECIAL PERMIT $ _LOT LINE ADJUSTMENT S TEMPORARY PERMIT S . _SHORT PLAT $ — CONDITIONAL USE PERMIT S _TENTATIVE PLAT $ _ _SITE PLAN APPROVAL $ _PRELIMINARY PLAT $ . FILL Cu.Yds: ) X VARIANCE $ (from Section:4-4-130) $ 250.00 P PLANNED �DEVELOPMENT $ • • Y _WAIVER $ _ROUTINE VEGETATION _FINAL • MANAGEMENT PERMIT $ _ BINDING SITE PLAN • MOBILE HOME PARKS $ SHORELINE REVIEWS: . SUBSTANTIAL DEVELOPMENT S CONDITIONAL USE $ _. VARIANCE • $ EXEMPTION $ X ENVIRONMENTAL REVIEW S 1,000.00 ~REVISION . . . . ' ' . .AFFIDAVIT::OF OWNERSHIP : . 1,(Print Name) I tltelt VIP t 01Jln ,declare that 1 am(please check one) . the owner of the property involved in tide application, ✓ the authorized representbive to act for the property owner(please attach proof of authorization),and thatthe foregoing staleme►[s and answers herein contained and the information herewith are in all respects true and cornet to the best of my lmowledae and belie£ I 1 certify that 1 know or have satisfactory evidence that��V tOt % ie t Q1SCL+signed this instrument and acknowledged it to be h" &their free and voluntary ac t'i rrhlee uses and purposestr meat Maw p `.�'� • , �,� -whir 72,144,1 a C a ss • I El , `� u.vi-0. .. 'o!�(Name ofOwnet/Repre e) . Notary%�ub ' i.ti i• n ington :`a�� '�,_ 72/ ' � Nett(arlt N- • �i R . �,U _� ' -.. (Signature of Owner/Represcntative) My a' t$nt p„ :• ,�. �/ _ p; Ofi Wp� ` H:IDMSION.SIUfIUTIE.SwOCS12000.237.doc1a °`//'e r i a l s r s t, TOTAL P.03 J (THIS SECTION TO BE COMPLETED BY CITY STAFF.) City File Number: ECF SA R SHPL CU LLA PP FP TP SP RVMP V AAD W FPUD SM SME MHP BSP A CPA TOTAL FEES: $ TOTAL POSTAGE PROVIDED:$ H:\DIVISION.S\UTILITIE.S\DOCS\2000-237.doc\a CITY OF RENTON • DEVELOPMENT SERVICES DIVISION MASTER APPLICATION OWNER(S). PROJECT INFORMATION(cont) Note: If there is more than on legal mimic,"please attach an additional notarized EXISTING LAND USE(S): Master application to each owner. L1 STORM DRAIN PIPE NAME: t ct n e 4 T h ADDRESS: 3--3 3 9 Pros e ( d # / l PROPOSED LAND USE(S): City: C'A .D C j CA , ZIP: �S y STORM DRAIN PIPE TELEPHONE NUMBER: — 4-to -5.71 - 9 ?ysCM-AI EXISTING COMPREHENSIVE PLAN MAP DESIGNATION CONTACT.PERSON/APPLICANT RESIDENTIAL RURAL NAME: Allen Quynn, City of Renton, Utility Systems Div. Surface Water Utility Section PROPOSED COMPREHENSIVE PLAN MAP DESIGNATION: ADDRESS: 1055 South Grady Way N/A EXISTING ZONING: City: Renton ZIP: 98055 RC—RESOURCE CONSERVATION TELEPHONE NUMBER: 425-430-7247 PROPOSED ZONING: N/A • PROJECT:INFORMATION : SI FT. ACREAGE): AREA(SQ. OR ACRE GE): PROJECT OR DEVELOPMENT NAME: THE PROPOSED PIPELINE WILL COVER AN AREA SUNNYDALE DOWNSTREAM STORM SYSTEM APPROXIMATELY .03 ACRES. REPLACEMENT PROJECT PROJECT VALUE: $150,000.00 PROPERTY/PROJECT/ADDRESS(S)/LOCATION: IS THE SITE LOCATED IN THE AQUIFER PROTECTION AREA? SEE LEGAL DESCRIPTION. NO KING COUNTY ASSESSOR'S ACCOUNT NUMBER: SEE ATTACHED IS THE SITE LOCATED IN ANY OTHER TYPE OF ENVIRONMENTALLY SENSITIVE AREA? SEE ATTACHED"PROPERTY IDENTIFICATION YES,THE SITE OR PORTIONS OF THE SITE HAVE LISTING". BEEN CLASSIFIED AS WITHIN THE SENSITIVE AREAS: STEEP SLOPES, SEISMIC, SLIDES, EROSION AND STREAMS. H:\DIVISION.S\UTILITIE.S\DOCS\2000-237.doc\a ,May-31 -O0 04 : 27A • b5/La/Lblt) *,:1: 1' 42b2//4366 SUNNYDALE PAGE 01 MAY-2S-.9.000 09:16 P.01 6407-$MaraRi w l A Oloige MitiirriCW.O!! (AU". torsi, The won M bow Jo at i!tam OM)d i.aim t..weak*inn.MEP a The M/a dill of tipro..e is et MI ieMew sew IC*ot iL011 NNW'lima ham. 1kt bow wad of few pyeA w M filiosreo of St I' OiaA Ili Ilu Rilt Atli.IL Mott 0lob Ydi y nary. The CCaw be Ins *imp 11011011.16 wide Mr pN}1t WIN ow r/Rtie1 amnia NO M'). roe glib 4010111.111 se IPA dory a■I wr lasing`A"r!jmw1/If. The MrmMrwlwl 11+SIP Mr boa'fhb C.Idle a,lb limb ofAAM 0.141ilatga of M! Wiwi MIRA br. Ito ININKY b Mw wit ML nli*i'1x num LLC. -..- 7 0wk ii. ilk iI Mww06e limb • $ .__._...,- M ►M141t '.. Mar $ _WI WS Al)11H71 S Y 1 _ _ UMW PLAT a w,�1611101ML WI NNW I . _ I —T' PLAT AT --.... _1IT PLAN APPROVAL I a lALM6tLV MIA? _„GRAM A Its,maw 1 ,.,taw.imAT 1 poi Mi.Raw 3 AMa Viol 4 4*A S an eL,MINIQ VW ammonium 9 ._.�_... i twMsR11�,N1Q • �T» Mu. - 1UI lr MsvSLoit+elrz S ...__._ EN i - x D�'1►�tOMi�fAl,WIPP $ 1 1 • -- •• - - - r ..- — _ ` A • ieni ris *avow wMM eid _p.m..tees it Or gillelma w AA �1r��,� rwoosa.�i �■+e�- we i'r�tw M Ion rIlaini/1aaoemst low.taw I••iwr wrrruwm wta�rd1 M�re �wrMwr r A N fieA+h 1.� .r.-.—.. , .. -sir. ..... ___________ , „„.„,... ..00MrsMassi. -arm 0.113 TGrAL P.01 May-31 -O0 04 : 27A John E. Woodring Attorney at Law State & Sawyer Building, Suite 201 ' 2120 State Avenue N.E. Olympia, Washington 98506 (360) 754-7667 FAX (360) 754-0249 BENT VIA FACSIMILE #(425) 430-7241 ORIGINAL MAILED May 31, 2000 Allen Quynn Engineer - city of Renton 1055 South Grady Way Renton, WA 98055 Re: 5unnydale Mobile Home Park - Development Services Division Ma,st�r Application • Dear Mr. Quynn: Pursuant to your request I am sending the faxed Affidavit of Ownership signed by Sunnydale Park owner Buyan Heath for the City of Renton Master Application for the stormwater pipe work at sunnydale Mobile Home Park and adjoining property. My client has requested that his signature on this document is exclusively for the purposes of affidavit of ownership of his property which is one of the properties where the stormwater pipe maintenance and repair work will take place. He and I are under the impression that in no way does his signature on this document commit him as the Park owner to any financial responsibility for the stormwater maintenance and repair activities that are the subject of this application. If this impression is incorrect, please so advise. My client's signature is contingent upon the above understanding. I understand you will be transmitting to me in the immediate future correspondence indicating the stormwater retention facilities in the Park are in proper working order. This correspondence will not relate to the stormwater pipe on the Park property that will be replaced until the subject master application. Thank you for your consideration. Sincerely, /•eb,/ OHN E./WOODRING '‘) Attorney at Law JEW:da Attachment cc: Bryan Heath via facsimile Gail Roy via facsimile (THIS SECTION TO BE COMPLETED BY CITY STAFF.) City File Number: ECF SA R SHPL CU LLA PP FP TP SP RVMP V AAD W FPUD SM SME MHP BSP A CPA TOTAL FEES: $ • TOTAL POSTAGE PROVIDED:$ • H:\DIVISION.S\UTILITIE.S\DOCS\2000-237.doc\a LAW OFFICES PETER D BALCH • JOOHNHN RICK P BRAISLIN FREDERICK ROBERT M COHON INT.COLL IER LIER TRACY L BROWN BETTS, PATTERSON & MINES, P.S. MEREDITH MARTIN A COPE D PAUL D CAREY CHARLES W.DAVIS WILLIAM P FITE THE FINANCIAL CENTER A DUR FRANCIS M H CARL H HAGENS ELSA A R S. INGRID W HANSEN 1215 FOURTH AVENUE RANCIEVEN GOLDSTEIN N BRUCE H HURST S THOMAS MAGNUSON SEATTLE, WASHINGTON 98161-1090 JEFFREY C.GRANT MICHDAVID L HENNINGS JOHN C PATTERSONINES (206) 292-9988 KENNETH S.McEWAN DALE C JAMES D NELSON DALE RIVELAND TELECOPIER: I206)343-7053 KIM C.PFLUEGER W TOMPKINS KIM C.PF U RICHARDSON LIVINGSTON WERNECKE DOJAMES P.SOLIMANO June 18 , 1984 W R.McKELVY 119721 F.B FITE 119691 ,� city oi;ei • Robert E. Bergstrom :_, �+ Engineering Supervisor Engineering Department City of Renton 200 Mill Avenue South rJUN 1 9 1986 Renton, Washington 98055 Re: McMahon/City Drainage and Maintenance Agreement Dear Bob: Enclosed herewith you will find a fully executed original of the Drainage and Maintenance Agreement, which our client has authorized to be delivered to you. The new page 2 has been initialed and made a part of the agreement. In your letter of May 17 , 1984 , you referred to the request of King County Public Works that the alignment of the off site drainage ditch be modified slightly to jog on to the McMahon property. To accommodate this change , you added a 30-foot strip to the legal description set forth on page two of the agreement. Based upon your explanation of the County ' s requirements and our visit to the site on June 15 , 1984 , our client has approved the request. Our primary concern was that the realignment of the drainage ditch onto the McMahon property would not impair the future development of that parcel. You indicated that there would be no difficulty constructing a drainage pipe as opposed to a ditch, or paving over the area, so long as access to the drain was maintained to enable the City to perform its maintenance function. This arrangement is satisfactory to our client . As far as we know, this concludes the matter of the Drainage Maintenance Agreement. We would very much appreciate it if you would advise the Issaquah office of the Department of Natural Resources that the agreement has been concluded, and that the City will be performing the maintenance in the Robert E. Bergstrom -2- June 18 , 1984 future . The Department had expressed some concern about the drainage problem in the area behind Mrs . McMahon' s former residence, and it would be helpful to us if you would advise the Department that the situation is now under control . Most sincerely , \-;:j‹ )- :=74.? ' Jgh P. s in JPB:jsk Encl. cc: Thomas F. McMahon DRAINAGE AND MAINTENANCE AGREEMENT IL THIS AGREEMENT made and entered into this 1.)L' day of ArI , 1984, by and between THOMAS F. McMAHON, Personal Representative of the Estate of John C. Edwards and the Estate of Anna G. McMahon, Deceased, and Rainier Sand and Gravel, Inc. , a Washington corporation, (hereinafter referred to collectively as "Grantor") , and THE CITY OF RENTON, a municipal corporation, (hereinafter referred to as "Grantee") . W I T N E S S E T H: WHEREAS, Grantor is the owner of certain real property in the City of Renton, and more particularly described herein, upon which is located a temporary storm drainage system for the purpose of draining surface water from surrounding property;. and WHEREAS, The City of Renton is desirous of obtaining a right of entry onto Grantor's property for the purpose of maintaining, operating, repairing and replacing said drainage system; and WHEREAS, Grantor is willing to grant the City of Renton a right of entry upon the terms and conditions hereinafter set forth. NOW, THEREFORE, in consideration of the mutual covenants and agreements herein contained, the parties agree as follows: 1. Grantor, by this agreement, does hereby grant to Grantee a right of access over, through, across and upon the real property hereinafter described, for the purpose of maintaining, operating, repairing, altering, replacing, or reconstructing an existing storm drainage system with all necessary appurtenances. Said property is located in the City 1 J � of Renton, King County, Washington, and is more particularly described as follows: A parcel of land situate in the SW 1/4 of Section 16, Township 23 N, Range 5 E, more particularly described as follows: The S. 150.00' of the NE 1/4 of the SW 1/4 of Section 16, Township 23 N, Range 5 E, W.M. , King County, Washington. TOGETHER with the S 150. 00' of the E 440.00' of Govern- ment Lot 1, Section 16, Township 23 N, Range 5 E, W.M. , King County, Washington. • TOGETHER with the N 70.00' of the E 440.00' of Govern- ment Lot 2, Section 16, Township 23 N, Range 5 E, W.M. , King County, Washington, less SR-169. TOGETHER with the east 350. 00 feet of the west 850.00 feet of the north 30 feet of the SW 1/4 of the SE 1/4 of Section 16, Township 23 N. , Range 5 E, Willamette Meridian, King County, Washington. 2. In consideration for the right of access herein granted, Grantee agrees, at its own cost and expense, to o1erate, maintain, repair, alter, replace and reconstruct the said storm drainage system, and do all things necessary to keep said drainage system open and properly functioning at all times. This includes, without limitation, the cleaning of the drainage ditch, the maintenance of pipes and culverts, and removal of silt from the ditch and siltation ponds as may be reasonably required from time to time. 3. Grantee shall have the right, without prior institution of any suit or proceedings at law, at such times as may be necessary, to enter upon said property for the pur- pose of operating, maintaining, repairing, altering, replacing or reconstructing said storm drainage system or making any connections therewith, without incurring any legal obligation or liability on account of such entry, provided, however, that such entry and all work performed pursuant to this agreement shall be accomplished in a workmanlike manner, and in a way which will not disturb, damage or destroy the improvements on the property. In the event any of the improvements are disturbed, damaged or destroyed, Grantee agrees to immediately 2 restore the same to the condition such improvements were in prior to Grantee's entry upon the property. 4. Grantee shall provide reasonable notice to Grantor prior to entering the property or performing work thereon. Grantee agrees to keep the property free of liens or encumbrances arising out of any of the work performed on the property pursuant to this agreement. Grantee further agrees to indemnify and hold harmless Grantor from and against any and all liability, claims, demands, actions or causes of action whatsoever, for personal injury, property damage or otherwise, arising out of or in any way relating to any of the work performed by Grantee pursuant to this agreement. 5. Grantor shall retain the right to use the surface of the drainage ditch, so long as said use does not interfere with storm drainage and so long as no permanent buildings or structures are erected on or over said drainage ditch. 6. Grantor and Grantee acknowledge that the existing drainage system located on Grantor's property is a temporary system which may be substantially altered or eliminated entirely at such time as the subject property is developed. Nothing herein contained shall be construed nor is intended to be construed as in any way preventing or precluding Grantor from developing the subject property, provided the existing drainage system is maintained, a suitable replacement drainage system is constructed, or surface water drainage is otherwise adequately provided for in a manner consistent with applicable state and local laws and ordinances. 7. This agreement shall be binding upon and the benefits thereof shall inure to the parties, their heirs, successors, assigns and personal representatives. 3 IN WITNESS WHEREOF, the parties hereto have set their hands the day and year first above written. GRANTOR: ESTATE OF JOHN C. EDWARDS c--By rY1'Lti +�' yYv YY� Thomas F. McMahon, Administrator ESTATE OF ANNA G. McMAHON Thomas F. McMahon, Executor RAINIER SAND AND GRAVEL, INC. By 6W -1 f' YY\'Y1 I .. Its President GRANTEE: THE CITY OF RENTON BY /ILG'L{_ lr . STATE OF WASHINGTON ) ss. COUNTY OF KING ) On this y%30 day of (/,p C- , 1984, before me personally appeared THOMAS/F. McMAHON, to me known to be the individual described in and who executed the within and foregoing instrument, and acknowledged that he signed the same as his free and voluntary act and deed for the uses and purposes therein mentioned. GIVEN under my hand and official seal the day and year first above written. /NOTARY PU L C '' aria for the tat ' of Washington, residing at F ii=ems'` ' STATE OF WASHINGTON ) ss. COUNTY OF KING ) On this ..( day of axUa , before me, the undersigned, a Notary Public in and for the State of Washington, duly commissioned and sworn, personally appeared THOMAS F. McMAHON and to me known to be 4 the President and respectively, of RAINIER SAND AND GRAVEL, INC. , the corporation that executed the foregoing instrument, and acknowledged the said instrument to be the free and voluntary act and deed of said corporation, for the uses and purposes therein mentioned, and on oath stated that he. D authorized to execute the said instrument and that the seal affixed is the corporate seal of said corporation. WITNESS my hand and official seal hereto affixed the day and year first above written. j �!� fix.... NOTARY PUBLIC n and for the State of Washington; residing at 5 .r 4 83-8-141 405 f' c, STORM DRAINAGE EASEMENT REC_.O F •0n CASHSL +:+:4::+:4:.00 J �- This agreement made this 11th - day of February , 19 85 , by and between King County, a political subdivision of the State of Was1Tii ton, hereinafter termed the Grantor, and the City of Renton , hereinafter termed the Grantee. WITNESSETH: That for and in consideration of mutual benefits, the Grantor herein does by these presents grant unto the Grantee, its successors and assigns, easements and right of way over, through, under, across and upon the following described property, situated in King County, Washington, to wit: EASEMENT "A" That portion of the Northwest 1/4 of the Southeast 1/4 of Section 16, Township 23 North, Range 5 East, W.M., King County, Washington, being a strip of land 15 feet in width having 7.50 feet on each side of the centerline described as follows: COMMENCING at the Southeast corner of said subdivision; thence N 1°04'23" E along the East line thereof 170.21 feet to the POINT OF BEGINNING.of said easement and centerline; thence S 55°41'00" W 50.00 feet; thence S 78°00'00" W 87.00 feet; thence N 80°00'00" W 150.00 feet; thence S 67°40'00" W 195.00 feet; thence S 53°37'48" W 112.05 feet; to the South line of said subdivision and the terminus of said centerline. 1% Purpose: Easement "A" The Grantee shall have the right to construct, O reconstruct, operate, maintain, and repair its storm drainage pipe line • with necessary appurtenances over, under and upon the above described strip of Cq• land. 0 N EASEMENT "B" o That portion of the Northwest 1/4 of the Southeast 1/4 of Section 16, Township 23 North, Range 5 East, W.M., King County, Washington, being a strip of land 40 feet in width described as follows: The South 40.00 feet of the West 800.00 feet of the Northwest 1/4 of the Southeast 1/4 of Section 16, Township 23 North, Range 5 East, W.M., King County, Washington. Purpose: Easement "B" The Grantee shall have the right to construct, reconstruct, operate, maintain, and repair an open storm drainage ditch and service road within the above described strip of land. The Grantor and Grantee herein, by accepting and recording this easement mutually covenant and agree to the terms and conditions described in detail in Appendix "A" attached hereto and by this reference made part of this agreement. DATED this 11th day of February , 1985 • LA b_cn KING COUNTY, WASHINGTON m O BY cn � oc' ._ _ `s ^� -`'r Randy Re lie u w TITLE County Executive Ix" G Z r , , STATE OF WASHINGTON) COUNTY OF KING ) ss / On this day personally appeared..befare me ///aiee�/ �20-41-9 S to me known to be the . 2 �i7 County Executive of g County, Washington, the person who signed the ai and foregoing instrument for King County for the uses and purposes therein stated and acknowledged to me that he signed the same as the free and voluntary act and deed of King County and that he was authorized to so sign. p GIVEN under my hand and official seal this 47! e2 day of a. r, 1 19 /' i an ': or tie • State of Washington residing at.-Du_ t/..; -!---, : CITY OF RENTON !�� � BY r )AVIGS�(J'ii,S OLV\ •-• Barbara Y. Shinpoch TITLE Mayor DATE February 8, 1985 OATTEST STATE OF WASHINGTON) City C terk to COUNTY OF KING ) ss �1-1 On this day personally appeared before me ilarhar Y_ Sh n i r)r1, and aXine Motor into me known to be the person:rho signed the above and foregoing Instrument for 00 the uses and purposes therein stated and acknowledged to me hathe signed the • same as the free and voluntary act and deed of theRepresentative ity and that he was authorized to so sign. GIVEN under my hand and official seal this 8th day of February , i 1985 . O / J 1. AR in an or✓the • . ' 2 State of ington residing at A APPROVED AS TO FORM & LE ITY: BY . De uty-P o at n to p DATE U • APPENDIX "A" Terms and conditions applicable to—easements "A" and "B" granted by King County. 1. PERMIT REQUIRED: Before any work is performed under this agreement, Grantee must o6tai n a right of way construction permit or a special use permit from the Real Property Division. To obtain said permit, Grantee shall submit complete plans and specifications of the proposed project including details of landscaping, and comply with any and all other provisions as more specifically set forth in the permit application. 2. DAMAGES: In the event that any damage of any kind is caused by Grantee in the course of performing any act authorized by this easement, Grantee shall immediately reimburse the damaged party to the full extent necessary to restore said party to the position he would have held absent said damage. 3. ASSESSMENTS: Neither Grantor, nor its property shall be subjected to any charge, assessment or expense arising from, growing out of, or in any way attributable to, the use, occupance, or actions authorized herein, whether within or without the confines of Grantor's property. If Grantor or its property is legally subjected to any such charge, assessment or expense, Grantee shall pay Grantor, as additional compensation for the rights granted in this instrument an amount of money equal to any such charge, assessment or expense paid by the Grantor. 4. HOLD HARMLESS: The Grantee agrees to protect and save King County, to its electecTan appointed officials and employees while acting within the scope u, of their duties as such, harmless from and against all claims, demands and causes of action of any kind or character, including the cost of defense thereof, arising in favor of the Grantee's employees or third parties on ✓ account of personal injuries, death or damage to property arising out of the GO• Grantees and/orn or in any its agents,way employeesin from the acts or or omissions of the representatives. 5. HIRING AND EMPLOYMENT: In all hiring or employment made possible or resulting rom tBs agreement, there shall be no discrimination against any employee or applicant for employment because of sex, age, race, color, creed, national origin, marital status or the presence of any sensory, mental, or physical handicap, unless based upon a bonafide occupational qualificatiqn, and this requirement shall apply to but not be limited to the following: employment, advertising, lay-off or termination, rates of pay t or other formsr reot of compensation, and selection for training, including apprenticeship. person shall be denied or subjected to discrimination in receipt of the benefit of any services or activities made possible by or resulting from this agreement on the ground of sex, race, color, creed, national origin, age, except minimum age and retirement provisions, marital status, or the presence of any sensory, mental or physical handicap. Any violation of this provision shall be considered a violation of a material provision of this agreement and shall be grounds for cancellation, termination or suspension in whole or in part of the agreement by the County and may result in ineligibility for further County agreements. 6. RESERVATIONS: Grantor reserves to itself, licensees, lessees, successors and assigns, the right not only to continue to keep and use or operate all other facilities or structures now upon on orrigbeneathnthelsurfacesoof, or above, the said described premises, but also or operate other facilities and structures, provided that said installations may be made without substantial interference with the use of the said premises as provided in this instrument. .. ......�..T. .._. .. . .._ �.._ _........- n... .-i... .-.nhi•: nF !•hn t .-�ninn .A i ` w • • 8. TERMINATION AND ABANDONMENT: If the use of the easement on the ' premises T a in its instrument for the purposes expressed herein shall be abandonded or discontinued, or if the Grantee violates any provision of this instrument, the said easement shall thereupon cease and terminate, and i Grantee shall surrender or cause to be surrendered to Grantor, to its , successors or assigns, the peaceable possession of the said described premises, and title to the said premises shall remain in Grantor, or its i i successors or assigns, free and clear of all rights and claims of Grantee. Upon termination of the easement for any reason, Grantee shall remove at his expense all facilities placed on said property by Grantee and restore the premises to a condition which is equivalent in all respects to the condition existing prior to installation of the facilities or to a condition which is , satisfactory to Grantor. If Grantee has not accomplished removal and restoration at the end of a ninety day period odoffollowing mtthe seeffective ll oftdate of revocation, termination or abandonment, necessary work and charge all of the costs to Grantee. 9. RESTORATION AFTER INSTALLATION: Following any construction, Grantee shall return t e raptor ss property to its original condition by fixing any damage Grantee's construction caused to Grantor's property, including but not limited to property damage to slopes, shrubbery, landscaping, fencing, roadway or structures. 10. EMERGENCY SITUATIONS: In the event of an emergency, Grantee shall take imme gate steps to perfo m any necessary repairs, and in the event Grantee fails so to do, Grantor may perform said necessary repairs at the sole cost and expense of Grantee. O11. OTHER APPLICABLE LAWS: Grantee shall comply with all federal, state N and local aws, and assume all cost and expense and responsibility in ri connection therewith, without any liability whatsoever on the part of Grantor. CV U, OD Special terms and conditions: 1. The final design of the Sunnydale Mobile Home Park detention facility has been approved for a maximum five (5) year release rate equal to 0.764 cubic feet per second and a twenty-five (251 year storm detention volume equal to approv6 cubic feet. Any Departmentin ofdPublicge Worksrate shall require prior al by the King County 2. The improving and upgrading of the drainage for the or thetpurposeioe f enhancing storm water runoff shall be completed by y four (4) years of the acquisition of the necessary rights in land owned by the Estate of Anna McMahon referred to in special use permit #FS-122-83. EXHIBIT _ • Project Narrative The purpose of the Sunnydale Downstream Storm System Improvement project is to replace 700 feet of 18-inch, corrugated metal storm pipe with a new High-Density Polyethylene (HDPE) pipe of the same diameter. The project is located in the Southeast quarter of Section 16, Township 23 North, Range 5 East W.M., City of Renton,King County Washington. The upper end is at the southeast corner of the Sunnydale Mobile Home Park;the lower end is near the intersection of SE 5th Street and Newport Ave. SE,north of the Maple Valley Highway. The project site is zoned Resource Conservation (RC). The project is bounded by the Sunnydale Mobile Home Park on the northeast corner of the site and the Maplewood Subdivision located near the project outfall to the south. The Mobile Home Park and Subdivision are zoned Residential Manufactured Homes(RMH)and Residential 8 du/ac.(R-8),respectively. Currently, the site consists of 700 feet of storm pipe and associated manhole structures. The site is heavily forested and includes steep slopes (70% in some places)and a groundwater fed stream which originates from the hillside. Based on the Soil Survey, King County, Washington (USDA Soil Conservation Service 1973), the area soils consist of Alderwood and a small amount of Puyallup soils at the lower end of the project. Alderwood soils are primarily gravelly sandy loam and Puyallup soils are primarily fine sandy loam. The proposed project is to replace an existing 700-foot-long corrugated metal storm pipe with a new High-Density Polyethylene (HDPE) pipe of the same diameter. The existing pipe is buried for 160 feet at the top of a slope. The remaining portion of the pipe is constructed above ground down, a steep slope. The upper 60 feet of the existing structure is partially crushed, and has resulted in joint separation and subsequent water leakage as well as a reduction in the conveyance capacity of the pipe. One of the two manhole structures on the slope has been undermined and is in danger of collapsing. The buried portion of the existing pipe crosses over two Olympic Pipe Line Company (OPLC) petroleum lines that run north-south along the top of the slope(see site map). The new pipe will be buried in the existing trench at the top of the slope, and will follow an improved above ground alignment to the bottom. The invert elevation of the proposed pipe at the OPLC crossing will be set at minimum of one foot above the petroleum lines. The new pipe will be designed to maximize the vertical clearance between the two facilities. It is anticipated that no clearing will be required, other than brush, for installation. The new pipe will have no intermediate structures, and will have an energy dissipator at the bottom to control scour. The existing pipe and structures will be removed as part of the project. The storm pipe replacement project will reduce erosion at the pipe outlet, and the chance of landslides occurring at the top of the slope as a result of the leaking pipe. The elimination of intermediate manholes will also reduce the chance of landslides and erosion occurring at other locations due to of pipe leaks or the failure of structures. The estimated construction cost of the proposed project$150,000. H:\DIVISION.S\UTILITIE.S\DOCS\2000-241.doc\AQ\tb Approximately 352 cubic yards of soil would be disturbed during pipe installation. There will be approximately 88 cubic yards of soil removed during construction of the outfall structure. The existing rock buttress will be dismantled and reassembled on-site. Some additional rock backfill for drainage will be placed at the rock buttress. Approximately 16 cubic yards of controlled density fill will be installed within the trench to protect the existing gas pipelines. The City will modify two existing drainage easement to account for the new pipe alignment. The City currently has existing drainage easements with King County and La Pianta, LLC. H:\DIVISION.S\UTILITIE.S\DOCS\2000-24I.doc\AQ\tb Construction Mitigation Description Construction on the proposed-project is scheduled to begin August 21, 2000, and end approximately four weeks later on September 18,2000. The contractor will begin work no earlier than 7:30 AM and will not continue to work past 5:00 PM. The contractor will enter the work site from two locations. The lower end of the project will be accessed via a city maintenance road off of the Maple Valley Highway near SE 5th St. The maintenance road runs approximately 2,000 feet, along the north side of the Maplewood subdivision were it terminates at the existing outfall. The upper end of the project will be accessed via a city maintenance road, which begins at the south end of Union Ave.NE and runs along the southern boundary of the Sunnydale Mobile Home Park. There will be no traffic or transportation impacts as a result of this project. Standard erosion and sediment control BMP's will be used during construction of the outfall to reduce sedimentation of the stream. Prior to beginning work, silt fence will be placed along the stream bank,between the disturbed area and the ordinary high water mark. To further minimize the introduction of sediment into the stream during construction of the energy dissipator, a temporary 18-inch bypass pipe will be installed to divert flows around the construction area. The pipe will be laid along the streambed on the opposite side of construction, beginning at a point approximately 20 feet upstream of the proposed structure. A sandbag headwall will be constructed by hand around the end of the pipe to act as a dam and direct the streamflow into the pipe. Plastic sheeting will be used on the upstream side of the headwall to minimize infiltration through the sandbags. The bypass pipe will discharge approximately 20 feet downstream of the energy dissipator. The bypass pipe and headwall will be removed immediately upon completion of the downstream work. Every effort will be made to minimize disturbance of vegetation in the 25-foot buffer area and in the overall project area. All disturbed areas will be stabilized with hydroseed upon completion of work. To minimize the impacts of equipment noise, construction will take place between the hours of 7:30 AM and 5:00 PM. It is not anticipated the project will produce dust or noxious odors. No special hours for construction and hauling are anticipated. The traffic control plan will be submitted by the contractor after award. The plan will be reviewed and approved by the operations section of the City Transportation Division. Letter of Certificate of Exemption Pursuant to RMC 4-3-050 Section C5-E3 (Utilities), it is requested that a Letter of Certification of Exemption be issued for construction in an area with slopes greater than 40%. H:\DIVISION.S\UTILITI E.S\DOCS\2000-241.doc\AQ\tb Justification for the Variance Request As part of the Sunnydale Downstream Storm System Replacement Project,the applicant requests a variance from RMC 4-4-130d, 3b for construction of an 18-inch, gravity stormwater discharge pipe within the 25-foot buffer of a stream. As demonstrated below, the request meets the four conditions for a variance. a. That the applicant suffers undue hardship and the variance is necessary because of special circumstances applicable to subject property, including size, shape, topography, and location or surroundings of the subject property; and the strict application of the Building & Zoning Code is found to deprive subject property owner of rights and privileges enjoyed by other owners in the vicinity and under identical classification; The proposed pipe alignment and associated outfall structure was chosen to minimize environmental impacts to the stream and surrounding area. Choosing to construct the pipe on the south side of the stream vs. over the current alignment(north side of stream) will avoid the need to construct a crossing and manhole structure adjacent to the stream, which would be susceptible to erosion and subsequent failure. The proposed alignment also eliminates the requirement for intermediate manhole structures at the top of the hill reducing additional soil disturbance. Because of the nature of the existing topography on the north side of the stream, it would be very difficult to construct an energy dissipator at the location of the existing outfall. The topography on the south side of the stream is relatively flat providing an ideal location for an energy dissipating structure. b. That the granting of the variance will not be materially detrimental to the public welfare or injurious to the property or improvements in the vicinity and zone in which subject property is situated;and, Replacing the existing system in a more stable location will reduce/eliminate system failer while better protecting public welfare and property. c. That approval shall not constitute a grant of special privilege inconsistent with the limitation upon uses of other properties in the vicinity and zone in which the subject property is situated; and Storm systems must eventually discharge to natural waterbodies, which can only be done by allowing work/construction within the 25-foot buffer. d. That the approval, as determined by the Hearing Examiner or Board of adjustment, is a minimum variance that will accomplish the desired purpose. This is the only variance required for working within the 25-foot buffer of a stream. As stated above, storm systems discharge to a natural waterbody or drainage course, which requires construction work within the 25-foot buffer.There is no other alternative. H:\DIVISION.S\UTILITIE.S\DOCS\2000-241.doc\AQ\tb E HIBIT 1 ' KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL 1.2.1 CORE REQUIREMENT #1: DISCHARGE AT THE NATURAL LOCATION All surface and storm water runoff from a proposed project that proposes to construct new, or modify existing drainage facilities must be discharged at the natural location so as not to be diverted onto, or away from, the adjacent downstream property. Diversion which will correct an existing problem will be considered as a variance (see Section 1.4). Discharge from the project must produce no significant adverse impact to the downhill property. Where no conveyance system exists at the adjacent downstream property line and the discharge was previously unconcentrated flow, the runoff must: (1) be conveyed across the downstream properties to an acceptable discharge point (see Core Requirement #2: Off-Site Analysis, in Section 1.2.2), with drainage easements secured from the downstream owners and recorded at the King County Office of Records and Elections prior to drainage plan approval, OR (2) be discharged onto a rock pad shaped in a manner so as to disperse flow (see Figure 4.3.51) if the runoff is less than 0.2 cfs peak runoff rate for the 100-year, 24-hour design storm event existing site conditions, OR (3) be conveyed to a dispersal trench (see Figure 4.3.6E in Chapter 4) or other infiltration system if the runoff is less than 0.5 cfs peak runoff rate for the 100-year, 24-hour design storm event existing conditions, provided the applicant can demonstrate that there will be no significant adverse impact to the downhill property. 1.2.1-1 1/90 KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL 1.2.3 CORE REQUIREMENT #3: RUNOFF CONTROL Proposed must projects provide runoff control through a combination of peak rate runoff control facilities and on-site biofiltration measures as described below. Peak Rate Runoff Control Proposed projects must provide peak rate runoff control to limit the developed conditions peak rates of runoff from specific design storm events not to exceed the pre-development peak rates for the proposed project site "existing conditions" as described below. Three basic methods for peak rate runoff control are possible: detention, retention, and infiltration. Detention is the collection and temporary storage of surface water (typically over several hours) with the outflow rate restricted--usually to the pre-developed outflow rate. Retention is the collecting and holding of surface and stormwater with effectively no surface outflow (outflow occurs by evapotranspiration). Infiltration is the soaking of surface water into the ground (typically for several hours or days). Infiltration not only reduces or eliminates surface runoff, but also helps to maintain the hydrologic balance of the surface water system. Infiltration can limit erosion and recharge groundwaters that supply water to wetlands, streams, and wells. Preserving infiltration after development is by far the most effective mechanism in preventing adverse impacts to the surface water system. Because of these benefits, King County encourages the use of infiltration systems for runoff control where the appropriate soil conditions exist. Proposed project peak rate runoff control must be located on-site. An exemption from on-site peak rate runoff control may be granted for the special conditions specified at the end of this core requirement section. Biofiltration , . I/ r,,-.: .•,-/` ,,ry Proposed project runoff resulting from more than five thousand square feet of impervious surface, and subject to vehicular use or storage of chemicals, shall be treated prior to discharge from the project site by on-site biofiltration measures as described in Section 4.6.3 in Chapter 4. The biofiltration design flow rate shall be the peak rate of runoff for the 2-year 24-hour duration design storm event. Note, biofiltration facilities installed following peak rate runoff control facilities may be sized to treat the allowable release rate (pre-developed) for the 2-year 24-hour duration design storm event for the peak rate runoff control facility. Biofiltration facilities installed prior to peak rate runoff control facilities shall be sized based on the developed conditions. Proposed Project Site "Existing Conditions" In performing the analysis for the design of runoff control, it is essential to first determine the proposed project site "existing conditions" from which the pre-development runoff rates can be computed for specific design storms. Existing conditions are not always synonymous with those of the natural, totally undeveloped site. In some instances substantial modifications (such as diversions, piping, clearing, and grading) have already increased and altered surface water runoff leaving the site, but no permit, nor accompanying engineering plan, was ever approved. In other instances, an approved drainage system exists and the existing system must be analyzed for its performance. There are two definitions for proposed project site "existing conditions" depending on the site. Sites with Existing Approved Drainage Systems: The proposed project site "existing conditions" are defined as those that occur with the existing drainage facilities constructed per approved permits and engineering plans. The current performance of existing drainage and detention facilities shall be determined by using the analysis methods described in Section 3.5 in Chapter 3. Sites with No Existing Approved Drainage Systems: The "existing conditions" are defined as those that existed prior to May 1979, which is the date of publication of "Requirements and Guidelines for Storm Drainage Control in King County" by the King County Public Works Department's Hydraulics Division, the 1.2.3-1 1/90 XHI I STORMWATER MANAGEMENT MANUAL FOR THE PUGET SOUND BASIN CHAPTER I-2 MINIMUM REQUIREMENTS FOR ALL NEW DEVELOPMENT AND REDEVELOPMENT I-2.1 INTRODUCTION • The 1991 Puget Sound Water Quality Management Plan (as amended) requires all counties and cities within the Puget Sound drainage basin to adopt ordinances to control runoff from new development and redevelopment by July 1994. The Plan also directs local governments to adopt stormwater programs which include minimum requirements for new development and re-development set by the Plan and in guidance developed by Ecology. These ordinances are to address: ". . . at a minimum: (1) the control of off-site water quality and quantity (as related to quality) impacts; (2) the use of source control best management practices and treatment best management practices; (3) the effective treatment, using best management practices of the storm size and frequency (design storm) as specified in the manual for proposed development; (4) the use of infiltration, with appropriate precautions, as the first consideration in stormwater management; (5) the protection of stream channels and wetlands; and (6) erosion and sedimentation control for new • construction and re-development projects." This chapter has been developed in response to the direction in the Plan. The reader is also referred to Volume II of the "Stormwater Program Guidance Manual for the Puget Sound Basin" (hereafter referred to as the Guidance Manual), a companion to this technical manual, which contains a model ordinance that incorporates these Minimum Requirements. There are several sets of requirements for proposed new development and redevelopment that are applied depending on the type and size of the proposed development. In general, small sites are required to control erosion and sedimentation from construction activities while larger sites must also provide permanent control of stormwater runoff. Sites being redeveloped must generally meet the same minimum requirements as new development sites for the portion of the site being redeveloped. In addition, redevelopment sites must provide source control BMPs for the entire site. There may also be situations in which additional controls are required for sites, regardless of type or size, as a result of basin plans or special water quality concerns. Development sites are to demonstrate compliance with the Minimum Requirements through the preparation of Stormwater Site Plans (SSP) . The plans are described in detail in Chapter I-3 and in the Guidance Manual. Two major components of these plans are an Erosion and Sediment Control (ESC) Plan and a Permanent Stormwater Quality Control (PSQC) Plan. The ESC plan is intended to be temporary in nature to control pollution generated during the construction phase only, primarily erosion and sediment. The PSQC is intended to provide permanent BMPs for the control of pollution from stormwater runoff after construction has been completed. For small sites, this requirement is met by implementing a Small Parcel Erosion and Sediment Control Plan. A flow chart demonstrating these requirements is shown in Figure I-2.1. Definitions: New development - means the following activities: land disturbing activities, structural development, including construction, installation or expansion of a building or other structure; creation of impervious surfaces; Class IV - general forest practices that are conversions from timber land to other uses; I-2-1 FEBRUARY, 1992 STORMWATER MANAGEMENT MANUAL FOR THE PUGET SOUND BASIN and subdivision, short subdivision and binding site plans, as defined in Ch.58.17.020 RCW. All other forest practices and commercial agriculture are not considered new development. Redevelopment - means, on an already developed site, the creation or addition of impervious surfaces, structural development including construction, installation or expansion of a building or other structure, and/or replacement of impervious surface that is not part of a routine maintenance activity; and land disturbing activities associated with structural or impervious redevelopment. Impervious surface - means a hard surface area which either prevents or retards the entry of water into the soil mantle as under natural conditions prior to development, and/or a hard surface area which causes water to run off the surface in greater quantities or at an increased rate of flow from the flow present under natural conditions prior to development. Common impervious surfaces include, but are not limited to, roof tops, walkways, patios, driveways, parking lots or storage areas, concrete or asphalt paving, gravel roads, packed earthen materials, anl oiled, macadam or other surfaces which similarly impede the natural infiltration of stormwater. Open, uncovered retention/detention facilities shall not be considered as impervious surfaces. Land disturbing activity - means any activity that results in a change in the existing soil cover (both vegetative and nonvegetative) and/or the existing soil topography. Land disturbing activities include, but are not limited to demolition, construction, clearing, grading, filling and excavation. Source control BMP - A BMP that is intended to prevent pollutants from entering stormwater. A few examples of source control BMPs are erosion control practices, maintenance of stormwater facilities, constructing roofs over storage and working areas, and directing wash water and similar . discharges to the sanitary sewer or a dead end sump. Throughout this Chapter, guidance to meet the requirements of the 1991 Puget Sound Water Quality Management Plan (as amended) is written in bold and supplemental guidelines that serve as advice and other materials are not in bold. I-2.2 EXEMPTIONS • -Commercial agriculture, and forest practices regulated under Title 222 WAC, except for Class IV General forest practices that are conversions from timber land to other uses, are exempt from the provisions of the minimum requirements. All other new development is subject to the minimum requirements. I-2.3 SMALL PARCEL MINIMUM REQUIREMENTS • ' The following new development shall be required to control erosion and sediment during construction, to permanently stabilize soil exposed during construction, to comply with Small Parcel Requirements 1 through 4, and to prepare a Small Parcel Erosion and Sediment Control Plan: (a) Individual, detached, single family residences and duplexes. (b) Creation or addition of less than 5,000 square feet of impervious surface area. (c) Land disturbing activities of less than one acre. I-2-2 FEBRUARY, 1992 EXHIBIT F a • CITY OF RENTON DETERMINATION OF NON-SIGNIFICANCE (MITIGATED) APPLICATION NO(S): LUA-00-071,ECF APPLICANT: • City of Renton/Surface Water Utility Division PROJECT NAME: Sunnydale Downstream Storm System Replacement Project DESCRIPTION OF PROPOSAL: The City of Renton is requesting Environmental (SEPA) Review for the replacement of the Sunnydale downstream storm system.' The proposal is to replace 700 feet of existing 18-inch- corrugated metal storm.pipe with new 18-inch high-density polyethylene pipe (HDPE). In addition to Environmental (SEPA) Review, the project requires a Certificate of Exemption from the City's Critical Areas Regulations in order to perform work on slopes in excess of 40% and within 25 feet of the ordinary high water mark of a creek. LOCATION OF PROPOSAL: Southwest of Sunnydale Mobile Home Park; North of SE 5th Street LEAD AGENCY: City of Renton Department of Planning/Building/Public Works Development Planning Section The City of Renton Environmental Review Committee has determined that it does not have a probable significant adverse impact on the environment. An Environmental Impact Statement (EIS) is not required under RCW 43.21 C.030(2)(c). Conditions were imposed as mitigation measures by the Environmental Review Committee under their authority of Section 4-6-6 Renton Municipal Code. These conditions are necessary to mitigate environmental impacts identified during the environmental review process. Appeals of the environmental determination must be filed in writing on or before 5:00 PM July 17, 2000. Appeals must be filed in writing together with the required $75.00 application fee with: Hearing Examiner, City of Renton, and 1055 South Grady Way, Renton, WA 98055. Appeals to the Examiner are governed by City of Renton Municipal Code Section 4-8- 11B. Additional information regarding the appeal process may be obtained from the Renton City Clerk's Office, (425)430- 6510. PUBLICATION DATE: July 03, 2000 DATE OF DECISION: June 27, 2000 SIGNATURES: MVOelfteet hi2-7/dO • • Gre i r an dministrator DATE Department of I ning/Building/Public Works .- •-• .3k_. ( :-.J,,, 4__,k c 7 00( Jim hepherd,Ad misty. or DATE 7 Con munity Services. -.7e--" ._ 4,,‘ s 7- ,0 • Lee W� el r, Fire C ief DATE 8. Renton Fire Department dnsmsign CITY OF RENTON DETERMINATION OF NON-SIGNIFICANCE (MITIGATED) MITIGATION MEASURES APPLICATION NO(S): LUA-00-071,ECF APPLICANT: City of Renton/Surface Water Utility Division PROJECT NAME: Sunnydale Downstream Storm System Replacement Project DESCRIPTION OF PROPOSAL: The City of Renton is requesting Environmental (SEPA) Review for the replacement of the Sunnydale downstream storm system. The proposal is to replace 700 feet of existing 18-inch corrugated metal storm pipe with new 18-inch high-density polyethylene pipe (HDPE). In addition to Environmental (SEPA) Review, the project requires a Certificate of Exemption from the City's Critical Areas Regulations in order to perform work on slopes in excess of 40% and within 25 feet of the ordinary high water mark of a creek. LOCATION OF PROPOSAL: Southwest of Sunnydale Mobile Home Park; North of SE 5th Street MITIGATION MEASURES: 1. The project shall comply with the recommendations contained within the Geotechnical Report prepared by Zipper Zeman Associates, Inc. dated May 10, 2000. • • mitmc,ci irac