Press Alt + R to read the document text or Alt + P to download or print.

No preview available

The URL can be used to link to this page

Home My WebLink AboutC_S_Singh_Short_Plat_On_Hold_Letter_180111_w_attachmentsJanuary 11, 2018 Phillip Kitzes PK Enterprises 23035 SE 263rd St Maple Valley, WA 98038 Subject: “On Hold” Notice S. Singh Short Plat, LUA17-000803, ECF, SHPL-A Dear Mr. Kitzes: The Planning Division of the City of Renton accepted the above master application for review on December 6, 2017. During our review, staff has determined that additional information is necessary in order to proceed further. The following information will need to be submitted before April 11, 2018 so that we may continue the review of the above subject application: Under a previous land use application made for this site (LUA05-089, SHPL-H, ECF), the City of Renton received professional studies identifying several onsite streams and one onsite wetland. A copy of some of the exhibits and figures from these previous report are included as an attachment for your reference (Attachment A). A copy of the land use file is available in Laserfiche through the Office of the City Clerk. Please revise and resubmit a Critical Areas Report that identifies and evaluates all existing critical areas onsite. Submitted reports shall comply with all current Critical Area Regulations of the Renton Municipal Code (RMC). Please note that the City may require an independent review of an applicant’s report when appropriate due to lack of substantial documentation of impact avoidance as part of the first study. Evaluation by an independent qualified professional is paid for at the applicant’s expense and is selected by the City (RMC 4-3-050F.6.a). A preliminary drainage plan and Technical Information Report (TIR) prepared by Core Design dated August 21, 2017 were submitted to the City as part of the site plan submittal. The site is located in the City’s Flow Control Duration Standard (Forested Site Conditions). The site is located in the Thunder Hills Creek drainage basin. The TIR was not completed in accordance with the standards found in the 2017 Renton Surface Water Design Manual (RSWDM). All nine core and six special requirements were not addressed. For example: o Due to the re-routing of surface water through the steep slopes onsite the final TIR needs to include a Level 2 downstream analysis for the proposed adjustments to the drainage path to satisfy Core Requirement #2, Offsite Analysis. The analysis will need to discuss the potential increase in erosion due to the increase amount of water volume. o Conveyance calculations were not provided in the preliminary TIR. Conveyance calculations shall be included in the final TIR to satisfy Core Requirement #4, Conveyance System. o A geotechnical report evaluating site soil conditions was prepared by the Riley Group dated March 14, 2017. The report recommends to not use any type of infiltration systems onsite due to the surface and subsurface conditions. One of the content requirements for a Geotechnical Report with medium and high coal mine hazards is to utilize test pits to investigate coal mine waste dumps and other shallow hazards such as slope entry portals and shaft collar areas. Drilling is required for coal mine workings or other hazards that cannot be adequately investigated by surface investigations. Please verify that the Geotechnical Report was prepared in accordance with the content requirement for all onsite geologic hazards (RMC 4-8-120D.7). All geotechnical reports prepared for geologically hazardous areas will be subject to an independent review by a qualified specialist selected by the City, at the applicant’s expense (RMC 4-3-050F.6.b). Please revise and resubmit all plans and application submittal items that are impacted through updated reports. Please provide me with a response to two (2) Public Comment Letters received by the City of Renton on January 5, 2018 (Attachment B). At this time, your project has been placed “on hold” pending receipt of the requested information. Please contact me at (425) 430-7289 if you have any questions. Sincerely, Clark H. Close Senior Planner Attachments: A) Existing Conditions Maps & Figures (dated 5/1/06, 6 Sheets) B) Public Comment Letters received on January 5, 2018 from Katherine George and Erick Thompson cc: Sukhvinder Singh / Applicant Collins, George, Skagen, Thompson / Parties of Record / / \ ~ ~ ;! ,8 /~ .,' . ,!,1'1<[""::'1 ',. "C ""1\'" ",1'("',1 III ' ""!'? ... . >,':1:1';):\';;,1 ., , ;"~~r-I!tC>~ , . . ,I.f· '1'\':. ,II' .u.l.j" i! \ ,0: ", i,ll .. I, " ,r"w."",T· . 1 . ".1 L ::). ~ J': " ,i ,,:,' ' ,,' I ,. 'I"~ ': :\"::"t' :<:1,'1 , I • _,'. " --I, '.' 1)'1 . . ·t ~.' I' " 'j ,,1\, . '. . , 1 (1"1 .,:.' "~!:',,~(I ,,'. "", ,,\ ~' .'I:~II IW _ !:t' i . ',:: ;1;'J':i,' '/; . ,~:\\j,X ~;,rt~,(, 'ii'::, Iii, EXISTIN6 , . , <, ~;,::!:tb;:r/',;:f:1 '. """ " "i,l'\I'i,'.sft;ie~,C,*j' ""'IH'I, ' ! .' .. ' ;.,.,'. .,: '. \II " ", ."' l' t} . I I ~'. .l' I I \\~\ ~ .:~/ / ROH TYP. ---< I STREAM '6'-,1 I-ETLA. ND 'A' ~115' BlFFER) :1,314 SF / ~ (25' EU'FERJ ">:-.. . ~ I ...... ~' " :"'->t":-,,~ ~ ~' C--,;:;d. '-:' . " . < -......:. • -~..., .... i: ::~: >:. >,>:::: ::~>. /"'" \ '~"""'"W'3''' . '. .:.'..,.., ~ ,-' .. /. . , .... "" ...... , .. ~. I 2....· '~"; :.a.~ :~:.;' :'.>"" eW-4 I I & .. ~. Hl.~ ". ";'. EZ3X ST. IN$, '. ........ 1'-· STRlJCTURE "~S~~M'G' , ;J ,~, "h' 6-4 s-.:z \ ...... -;~TYLllE ~,,', ~ ~ ' ........ ~TLAND 'A'eNL.AIliteeMeNT _M 1M. ii~ >_ 1 i pc L>EM ,----' ~ .. -----~ ': L ,11 ,!,I,. i' :r':' .:\l I~. f/*Tlt" std' ',:'" ". TlN4:lB , , i I . .:,.;;r' ,,', (., ,'~'\!:;::~~:" I PL~N L.1:c9I:Nt::' I I ~" ... ' I SHOIlitTP. .... L;.::.A~.:'''· • .';· ~ I --,,~ '" . I I ,.'i",,'I'\·· I .. ' _. ..'n .. ~ ". I TIIit!~~.'.".i."'I.;'.1 '/':.:;-.>, ~ I I c:: I·.....:..:::J EXiSTIN6 ~TlN<ID ,"""'"'' .'<' ' I ,~,~-- EXISnN6 STRlJCTURE ,Jj L V.·,~ '};'~"' ... ':::,4< ,Ii: ! III I ..... SmEH-! I f\lISTORIC"L FIIN HOUSE) . --t---'. it""" i'. ,,:'" .~' "il .• :' J' I ew-e ~ FLM . • J. '''''",,'' ,,,,,,, -~'"' ..... • ,~.. ' .'.' ' .. "p.". . -~ 0= --" r:::;-"--..,:~ . '" ..........·.:r.:::::.' •. :.:'''',:·· +---="'"""~~-~'''"'''" '. ""_ ro ",.."re " ~ ,.", ,,, ..• " •. ' ","",,~re "'-" ""'"~ """" /' ...~ , .. " ., ., " .. "" ~ NOTES \. ..--. ~;"\IIf"'~I.,,;l.CL" .. "; •. ,~.n~'~' '>" /"",,,: \"';:-'1," ~VI~ r'LAN /,~l~i SITE P\.JIN PROVIDED BY CORE DESI,,", 14111 IE 2<lTll PL. SUITE 101, Ba.LEWE, I1A '10001 (425}!le5-1em. 2. ~E 1JRAI.iN61r1AS MODIFIED BY T"LASAEA CON5UL. TIINTS FOR V15UAl. ENlANCEt1:NT. ED TALASAEA CONSULTANTS, INC. Resource & Environmental Planning 15020 Eear Creek Road Northeast Woodinville, Washington 98077 Eus (425)861-7550 -Fax (425)861-7549 EXHIBIT _ FI6URE 2 DESIGN EXISTING CONDITIONS FOR SCALE OVERALL SITE a V'-IETLAND ENLARGEMENT AS NOTED DEFOOR PROPERTY DATE RENTON, V'-IA 5/1/06 REVISED PROJECT CJ31 © Copyright -Talasaea Consultants, INC. / / \ ~ ~ ;! ,8 /~ .,' . ,!,1'1<[""::'1 ',. "C ""1\'" ",1'("',1 III ' ""!'? ... . >,':1:1';):\';;,1 ., , ;"~~r-I!tC>~ , . . ,I.f· '1'\':. ,II' .u.l.j" i! \ ,0: ", i,ll .. I, " ,r"w."",T· . 1 . ".1 L ::). ~ J': " ,i ,,:,' ' ,,' I ,. 'I"~ ': :\"::"t' :<:1,'1 , I • _,'. " --I, '.' 1)'1 . . ·t ~.' I' " 'j ,,1\, . '. . , 1 (1"1 .,:.' "~!:',,~(I ,,'. "", ,,\ ~' .'I:~II IW _ !:t' i . ',:: ;1;'J':i,' '/; . ,~:\\j,X ~;,rt~,(, 'ii'::, Iii, EXISTIN6 , . , <, ~;,::!:tb;:r/',;:f:1 '. """ " "i,l'\I'i,'.sft;ie~,C,*j' ""'IH'I, ' ! .' .. ' ;.,.,'. .,: '. \II " ", ."' l' t} . I I ~'. .l' I I \\~\ ~ .:~/ / ROH TYP. ---< I STREAM '6'-,1 I-ETLA. ND 'A' ~115' BlFFER) :1,314 SF / ~ (25' EU'FERJ ">:-.. . ~ I ...... ~' " :"'->t":-,,~ ~ ~' C--,;:;d. '-:' . " . < -......:. • -~..., .... i: ::~: >:. >,>:::: ::~>. /"'" \ '~"""'"W'3''' . '. .:.'..,.., ~ ,-' .. /. . , .... "" ...... , .. ~. I 2....· '~"; :.a.~ :~:.;' :'.>"" eW-4 I I & .. ~. Hl.~ ". ";'. EZ3X ST. IN$, '. ........ 1'-· STRlJCTURE "~S~~M'G' , ;J ,~, "h' 6-4 s-.:z \ ...... -;~TYLllE ~,,', ~ ~ ' ........ ~TLAND 'A'eNL.AIliteeMeNT _M 1M. ii~ >_ 1 i pc L>EM ,----' ~ .. -----~ ': L ,11 ,!,I,. i' :r':' .:\l I~. f/*Tlt" std' ',:'" ". TlN4:lB , , i I . .:,.;;r' ,,', (., ,'~'\!:;::~~:" I PL~N L.1:c9I:Nt::' I I ~" ... ' I SHOIlitTP. .... L;.::.A~.:'''· • .';· ~ I --,,~ '" . I I ,.'i",,'I'\·· I .. ' _. ..'n .. ~ ". I TIIit!~~.'.".i."'I.;'.1 '/':.:;-.>, ~ I I c:: I·.....:..:::J EXiSTIN6 ~TlN<ID ,"""'"'' .'<' ' I ,~,~-- EXISnN6 STRlJCTURE ,Jj L V.·,~ '};'~"' ... ':::,4< ,Ii: ! III I ..... SmEH-! I f\lISTORIC"L FIIN HOUSE) . --t---'. it""" i'. ,,:'" .~' "il .• :' J' I ew-e ~ FLM . • J. '''''",,'' ,,,,,,, -~'"' ..... • ,~.. ' .'.' ' .. "p.". . -~ 0= --" r:::;-"--..,:~ . '" ..........·.:r.:::::.' •. :.:'''',:·· +---="'"""~~-~'''"'''" '. ""_ ro ",.."re " ~ ,.", ,,, ..• " •. ' ","",,~re "'-" ""'"~ """" /' ...~ , .. " ., ., " .. "" ~ NOTES \. ..--. ~;"\IIf"'~I.,,;l.CL" .. "; •. ,~.n~'~' '>" /"",,,: \"';:-'1," ~VI~ r'LAN /,~l~i SITE P\.JIN PROVIDED BY CORE DESI,,", 14111 IE 2<lTll PL. SUITE 101, Ba.LEWE, I1A '10001 (425}!le5-1em. 2. ~E 1JRAI.iN61r1AS MODIFIED BY T"LASAEA CON5UL. TIINTS FOR V15UAl. ENlANCEt1:NT. ED TALASAEA CONSULTANTS, INC. Resource & Environmental Planning 15020 Eear Creek Road Northeast Woodinville, Washington 98077 Eus (425)861-7550 -Fax (425)861-7549 EXHIBIT _ FI6URE 2 DESIGN EXISTING CONDITIONS FOR SCALE OVERALL SITE a V'-IETLAND ENLARGEMENT AS NOTED DEFOOR PROPERTY DATE RENTON, V'-IA 5/1/06 REVISED PROJECT CJ31 © Copyright -Talasaea Consultants, INC. ATTACHMENT A - - -~ .... 1_ --- -~ - _ ~ ___ , __ ,,6"--_ ------------------~;x:r~lff~~- BUILDING or:: ," -----5 T-f'i.-AM ~ -B----- I .. ----------------------------------------------~ET~L~D --'Sr ---- "" .. ,S:IG-LEAF MAf?tE IN CHANNEL' '~ I, j ... -[, • ... \ \ \ '\ \ I \ / <J T' --' ,'. r I d. "1,"' , <J .d L\ \ \ -\-,-, \ - \ , \ \ if' \ ' \ \ \ FI6UR ~" '. __ .-~,,_-;-_,":-~_'~ 'I' ----...... -~-\ ~ ----... ",-" "--;'~J ' . --' --~~ -. -. . ...... '" ' . -_' ' " I FIGURE I ..... , ..... ,"'. ~ o ! . ,I ..j /' , -,~~--___ ' __ ---"Ii I,," _'-,. ______ --Ex' 012" DI'A • ..t'· • tfII> "" ' ,..:..,...-,\ It ,---~ --;-~ tN FI:URE 14' " \ ../ • • \' -. 5TJ11t!AM/VtETLANl:' lei ENJ..AfIte!MENT GRAPHIC. SCALE ®NORTli (IN FEeT) , ...1 I b ~ 2~ NOT5 SITE PLAN PROVIDID BY CORE DESleN. 14111 IE 2'ITli PL. SUITE 101. 6aLEWE. HA '0001 (425)~5-1t'>11. 2. SCURC.E DRAHI'I6 HAS MODIAED er TALA5AEA CON!:U.. TANTS FOR VISUAL ENHAN(;EMENT. $TALASAEA CONSULTANTS, INC. Resource & Environmental Planning 15020 Bear Creek Road Northeast Woodinville. Washington 98077 BUB (425)86J-7550 -Fax (425)86J-7549 :'~ , 6 1 G~LVERl' EXHIBIT -FIGURE 3 STREAM B DEFOOR PROPERTY RENTON, HA DESIGN SCALE AS NOTED DATE 5/1/06 REVISED PROJECT «131 © Copyright -TaIasaea Consultants, INC. ~ ~ ,! ' -( I ( ;' i / . ' I 'C " '- { \. r I, \ ~' \ PLE~ " I . / '--..,-~ ./ / ( I /1' Ifi /' .\ \. \. ~, I ~ { //t\ "i - ~' .' /--- .t I " I j /.;> \ STREAM e 6RAF'HIC. 5C.ALE ® (IN FEET}- I ; I I HIMALAYAN BLACKBERRY UNDERSTORY E9TALASAEA CONSULTANTS, INC. Resource & Environmental Planning 15020 Bear Creek Road Northeast Woodinville. Washington 9aO;; Bus (425)861-7550 -Fax (425)86J-7549 EXHIBIT _ FIGURE 4 STREAM B SECTION DEFOOR PROPERTY RENTON, HA )\:!; \ \~' \\l~~ \ INCISED CHANNELS HITH VERTICAL SIDE-SLOPES DESIGN SCALE AS NOTED DATE 5/1/06 REVISED / I ~/ ~/ / " ( 6' PROJECT ct31 © Copyright -Talasaea Consultants, INC. (ED TALASAEA CONSULTANTS, INC. Resource & Environmental Planning 15020 Ilear Creek Road Northeast Woodinville. Washington 98077 Ilus (425)861-7550 -Fax (425)861-7549 ", "- I \. \ © Copyright -Talasaee Consultants, INC. /!II: STREAM,IA I 1'Ii'I .. o!II! ,I. . ... .~ .. ---- ... .. STReAM A NOTES 4' ~ .. '" " '. -.\------, 51n: PLAN PROVIDe:> 51' CORE DE5leN, 14111 IE 2'lTll PL 9JITE 101, ElELLEVUE, II'IA QtlOO1 (4:25}e/}5-1em. 2. ~E DRAI-IIN51oo1A5 MCOIFIED BY TALA5AEA CON9JLTANTS FOR VISUAL ENlANCeeIT. , i , ! • • "'" :/ %' ii'\' : \,.\) ".' ,'I' 1 , '\' , .. I ~ / .. /~ ,,~I "'" ,fill -----~ -----I ~' "-.. ~, ~ FIGURE 15 (!) TALASAEA CONSULTANTS, INC. Reeource & Environment.al Planning 15020 Bear Creek Road Northeast Woodinville, Washington 9a077 BUB (425)861-7550 -Fax (425)861-7549 .. / ,. /",' ~ EX. 12" DIA C;UL\VERT i ·'1 .. . ,~ Ii fill • I PR@PERTY' ,: . i / .' I I LIN,,'.E/,,~,,:! , " RON.' 'i ' ,,-, , , ' , I ~ '\ , .'1 • \ ~ir ~: DRAINAGE 'I ,~ . .. \ -\, .. , / 1/ EXHIBIT _ FIGURE 6 STREAM A DEFOOR PROPERTY RENTON, HA ,. 11't :. r, ) .. ' .. :d I , , I , ., " " DESIGN SCALE AS NOTED DATE 5/1/06 REVISED 'z C) I~ z w .~ PROJECT Cj31 © Copyright -Talasaea Consultants, INC. " / (, / ,I J II L\\ , I' '\' r:'~\' ''-_''\ I \ ' " " \~ . t'1l" ' \"--' j;) iF3:~ ;",1 ,T j~u'L. ,I., If ""'-"4-!JI,Jl\-f A STIlt!AM A {9TALASAEA CONSULTANTS, INC. Reeource & Environmental Planning 15020 Bear Creek Road Northeast Woodinville. Washington 98077 Bus (425)861-7550 -Fax (425)861-7549 EXHIBIT _ FIGURE 1 STREAM A SEG TION DEFOOR PROPERTY RENTON, HA " I \ ~ I ' I \ Ii )r / ,., \ "'~~ r\.-i;¢'" W'If __ . AI NATIVE FOREST UNDERSTORY SCALE AS NOTED DATE 5/1/06 REVISED PROJECT '131 © Copyright -Talasaea Consultants, INC. RECEIVED 01/05/2018 cclose PLANNING DIVISION ATTACHMENT B 4,514 376 City of Renton Print map Template This map is a user generated static output from an Internet mapping site and is for reference only. Data layers that appear on this map may or may not be accurate, current, or otherwise reliable. None 1/4/2018 Legend 2560128 THIS MAP IS NOT TO BE USED FOR NAVIGATION Feet Notes 256 WGS_1984_Web_Mercator_Auxiliary_Sphere Information Technology - GIS RentonMapSupport@Rentonwa.gov City and County Boundary Addresses Parcels Environment Designations Natural Shoreline High Intensity Shoreline Isolated High Intensity Shoreline Residential Urban Conservancy Jurisdictions Streams (Classified) Type S Type F Type Np Type Ns Wetlands January 5, 2018 Clark H. Close Senior Planner City of Renton CED - Planning Division 1055 South Grady Way Renton, Wash. 98057 Sent via email to: cclose@rentonwa.gov Re: Public Comment Letter, LUA17-000803 (Singh short plat) Dear Mr. Close, I am the owner of the house at 1301 S 9th Street in Renton, WA. I received notice of a plan to develop the lot across Renton Ave S from my house. I requested and was granted an extension of the public comment period due to numerous concerns I have about the development of that lot. I appreciate your assistance in providing information about the project. My concerns are centered around soil stability due to coal mine hazards, and due to presence of a wetland and stream in the area to be developed. The existing documentation does not address these concerns. Property location The property that is considered for development (LUA17-000803- S. Singh Short Plat), is located on the west side of Renton Ave S, between S 9th and S 10th streets, in the Renton Hill neighborhood. The site plan, as provided by the owner, is shown in Figure 1 below. RECEIVED 01/05/2018 cclose PLANNING DIVISION Figure 1 - Site Plan Coal Mine Hazards The Renton Hill neighborhood was the site of extensive coal mining in the late 19 th and early 20th centuries. There are a number of maps available of the mining area, as well as known areas not covered by maps. Map of the Seattle Electric Co.'s Renton coal mine The Washington State Department of Natural Resources has a recording of a map of coal mining area as of June 20, 1918. The entire map can be downloaded from the DNW1. The overall map as overlaid on the modern map of the area is as follows, with the area in question highlighted. 1 https://fortress.wa.gov/dnr/geologydata/coal_maps/geospatial_pdfs/K31_A.pdf Figure 2-K31A Figure 3-K31A-Lot Below is the approximate area represented in the highlighted area above. The key features that allow for locating the map are the shaft that runs south-west from the north side of the area, and the shaft that runs approximately north from the center of the south side of the area. Figure 4-K31A-Zoom From this map, it can be seen that there are multiple shafts, air ways, and worked out areas under the lot. In particular, the Second North Gangway runs directly through all the proposed lots. This is an area that has had significant material/coal removed. Also note that that other gangways run roughly match the path of alleys in the area. I’ve spoken with a number of long term residents of the area over the years, and those that are aware of the mining noted that the alley was placed over a mined -out area. Map showing the upper coal mining operations of the Renton mine under the city of Renton The Washington State Department of Natural Resources has a recording of a map of the upper coal mining areas as of 1955. The entire map can be downloaded from the DNW2. This map contains the modern street grid, and so can be directly viewed. Figure 5-K32_E Zoomed 2 https://fortress.wa.gov/dnr/geologydata/coal_maps/geospatial_pdfs/K32_E.pdf As compared to the mined-out area from the 1919 map (K31_A), the 1955 map shows a much larger mined out area in the western half of the lot, but does not contain the mined-out area to the west of the Second North Gangway, which underlies portions of the eastern side of the lot. City of Renton Coalmine hazard area The City of Renton provides an online GIS tool that allows for the visualization of various datasets, including areas with significant coal mine hazard. The GIS tool for the area with the proposed lot shows the following. Figure 6-City of Renton Coalmine The area under the northeast portion of the proposed lots is clearly in a high hazard area. When combined with the historical maps, the reason seems clear, as there is both worked out areas, gangways, and various shafts running throughout the area. Renton Historical Museum The Renton Historical Museum has a composite map available for purchase that contains some of the known coal mines overlaid on the current street grid. A photo of the area with the lot is shown below. Figure 7-Renton Museum Map The map shows some of the same features as the other maps, along with additional features . However, there are some features missing that are present in other maps. For example, air way to the north of the main slope does not appear on this map, but does appear on the K31A map, along with a shaft parallel to the air way to the north. What this map does illustrate is that there is a confluence of tunnels under the proposed building lot on both the east and west side. There are 4-5 areas where multiple tunnels/shafts/gangways intersect, which would likely impact the maximum load. Uncertainty of mapping In addition to showing that there is a great deal of coal mine work underlying the proposed building lot, these maps also contain a disjoint set of information. Not all maps agree on both the features and their relative and absolute position. This aligns with my conversations with both longtime residents, and museum staff, in which they expressed the belief that the full extent of the coal mining was not fully known, both in terms of the overall structure of shafts, gangways, air vents, etc. but also in terms of their positions. With that said, all the maps show the variety of features that underlie the proposed lot. Impact of Coal Mines The impact of coal mine hazard areas is not theoretical. When I purchased the house at 1301 S. 9th Street in 2008, I checked the soil, and confirmed that the house was built on clay (likely tailings from the mine). At the time I moved in, there was a single crack in the foundati on and no cracks in either of the driveways, and all the floors were level. The lot next door (910 Renton Ave S) had a mine entrance/air way/shaft (the nature wasn’t clear) in the eastern portion of the lot. The lot was purchased, and a large house was built on it. I made the owners aware of the mine prior to construction starting, and he expressed surprise and said he wasn’t aware of a coal mine entrance. Nevertheless, construction was started without any preparation, at least that I could see. As a result, there were issues that arose during the construction of the house that could have been prevented. Sometime during or soon after the house was built, the land shifted , resulting in half of my house having a slight slope (enough that a ball will roll on t he floor), and a number of cracks in the foundation and driveway. The construction process was very opaque, but there was a great deal of concrete poured, and my understanding from overhearing the workers is that it was due to the mine. T he construction ended up taking the better part of a year, with multiple work stoppages and many visits by various geo-technical firms. This shows the impact of the coal mines and also illustrates the general quality of the construction process. The same owners are developing the lot in LUA17-000803, and so I am especially concerned about shortcuts and inadequate planning and preparation. Geotechnical Engineering Report I received a copy of the geotechnical engineering report prepared by “The Riley Group, Inc” for the builders of the proposed lot. This report contains the following. 4.6.1 COAL MINE HAZARD Review of coal mine maps in the area indicates the Renton Coal Mine had extended coal mine workings below the site. The main entrance to the Renton Coal Mine was to the west of the site at the base of the slope, with the Main Slope No. 3 Seam extending through the southern portion of the site, descending at 11 degrees. A No. 3 Seam Airway tunnel ran parallel to the Main Slope, extending through the site just north of the southern property line. The First North Gangway mine workings extended north from the Main Slope through much of the western and central portions of the site, and the Second North Gangway extended north from the Main Slope along the eastern property line. The First South Gangway extended south from the Main Slope in the southeast site corner. Based on the definition for Coal Mine Hazards in the RMC, and our understanding of the Renton Coal Mine workings, we believe the western half of the property meets the classification of High Coal Mine Hazard (CH), with mine workings shallower than 200’, and the eastern half of the site meets the classification of Medium Coal Mine Hazard (CM), with mine workings greater than 200’. No indications of subsidence was observed on the site during our exploration. Based on our current understanding of the proposed development, work will be limited to the eastern half of the site. (Highlighting added). The maps above clearly show that while the western half contains a number of mine hazards, it also shows that the eastern portion of the lot also contains a great number of mine features that would seem to indicate a higher level of hazard. Summary of Coal Mine Hazard Half of the building lots (the ones on the north side) are over a High Coal Mine Hazard area, and the remainder are very close to known shafts and gangways. The lot is heavily sloped east -west, and so any collapses of the site will potentially impact the lots on the east side of Renton Ave S. As explained in the accompanying letter from my attorney, the known hazards outlined above and the inadequate study by the applicant warrant extra precaution, including at a minimum: a) referral of the application for public hearing and hearing examiner review; b) independent review of the geotechnical report; and c) a determination of significance and environmental impact statement. Wetland/Stream CRITICAL AREAS REPORT I received a copy of the Critical Areas report prepared by “Habitat Technologies” for the builders of the proposed lot. The stream outlet on the northeast corner of the lot was marked as seasonal and runoff based. The stream is in the storm drain, and while it does run more heavily in the winter, it is a year - round stream that drains into a marshy area in the northeast corner of the lot. I believe that this stream is what supplies the wetland identified by the City of Renton online GIS tool. Figure 8-Wetland My observations is that the wetland is larger, and stretches almost to Renton Ave S, where the stream outlet is located. There are frogs and lizards in this area, as my kids and I would go across the street and see them. You can hear the frogs very well all summer. Opening the storm drain to access the st ream is actually our earthquake water source in case of emergency. The plan shows that corner as being one of the lots (lot 1). Drainage If the area where the stream outlet currently exists is part of a lot, how will the stream be drained? Is the storm sewer going to be extended, and the stream outlet moved to the west of the lots? If the drainage isn't handled, then the soil will become saturated with water, making it more likely to experience soil movement, and given the slope of the lot, any sliding wo uld impact lots uphill of the proposed site, including my house. One of the nice aspects of living near the stream outlet is that we have a large variety of birds in the area, as well as frogs and lizards. If the wetland is developed, will a portion of the lot be allocated to replace it? As explained in the attorney’s letter, the existence of a year-round stream warrants additional study and environmental protection. Thank you for your careful consideration of these concerns. Sincerely, Erick Thompson