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HomeMy WebLinkAbout1.4 Application Part 5PVCMI Land Planning Division 1038 County Road 323 Rifle, CO 81650 Ph. 970-625-5350 Fax 970-625-4522 Email: pvcm@hughes.net Project: Cottonwood Compressor Station to Webster Hill 24 inch Gathering Line. Submittal Item Tab 9- Project Facilities 9.07.04 (8) The Cottonwood Compressor Station to Webster Hill 24 inch Gathering Line project facilities are noted in attached mapping prepared by DR Griffin & Associates in tab 2 - Vicinity Map 9.07.04 (1). Additionally, please find attached within this tab, detailed drawings and geotechnical reports for the Rabbit Brush and Webster Hill Compressor Stations. The following information is attached: (1%. Rabbit Brush Compressor Station- Please find this information in Tab 9- Project Facilities. Harris Group, Inc. RB -CI -6401 Rev. 1 3/9/07 Stamped by Judith Secary P.E. RB -CI -6402 Rev. 1 3/9/07 Stamped by Judith Secary P.E. RB -CI -6403 Rev. 1 3/9/07 Stamped by Judith Secary P.E. RB -CI -6404 Rev. 0 2/15/07 Stamped by Judith Secary P.E. RB -CI -6405 Rev. 0 2/15/07 Stamped by Judith Secary P.E. Rabbit Brush Compressor Station- Geotechnical Engineering Group, Inc. Job 2526 Geotechnical Investigation Report dated 12/15/06. i . Webster Hill Compressor Station - Please find this information in Tab 9- Project Facilities. Harris Group, Inc. WH -CI -6401 Rev. 0 2/15/07 Stamped by Judith Secary P.E. WH -CI -6402 Rev. 0 2/15/07 Stamped by Judith Secary P.E. WH -CI -6403 Rev. 0 2/15/07 Stamped by Judith Secary P.E. WH -CI -6404 Rev. 0 2/15/07 Stamped by Judith Secary P.E. WH -CI -6405 Rev. 0 2/15/07 Stamped by Judith Secary P.E. Webster Hill Compressor Station- Geotechnical Engineering Group, Inc. Job 2526 Geotechnical Investigation Report dated 12/15/06. Page 1 of 6 C. Construction and Permanent rights-of-way widths are detailed below. The surface agreements are attached in Tab 5- Evidence of surface owner notification and of surface agreements 9.07.04 (4). Additionally, the working space and spoil space are noted on the DR Griffin & Associates drawings in tab 2. Summary ROW Length and Acreage Totals For Federal and Fee Lands 24" Trunk Line and 12" Jumper Lines Two Compressor Stations 24" Bargath Gathering Pipeline Pro'ect Bargath Inc. % Williams Production RMT Company Owner Length LF Permanent ROW 50' Acres Construction ROW 75' ACRES Extra Workspace at 9% Total Acres Total Surface Area Acres Federal Lands 7,298 8.38 12.57 1.24 13.81 Fee and CDOT Lands 47,484 54.50 81.76 8.09 89.84 Total Lands for Pipelines 54,782 62.88 94.33 9.33 103.65 Lands for Stations — All Fee 28.52 Additional details regarding these issues are noted in tab 22- Construction Management Plan. D. Technical Details: DESCRIPTION OF COMPRESSION AND DEHYDRATION FACILITIES — RABBIT BRUSH AND WEBSTER HILL Following is a description of the proposed facilities to be installed at the Rabbit Brush and Webster Hill Compression & Dehydration Facilities. INLET SEPARATION This system will be designed to separate liquids from the station inlet gas (2 -phase separation) for the full build -out of 160 MMSCFD at 200 PSIG operating pressure. These liquids can be in the form of periodic pipeline slugs or may be continuously entrained droplets in the gas stream. The maximum droplet size specification for gas leaving the scrubber is 25 microns. The maximum slug size for design purposes is 50 barrels. This event will occur no more than once every 24 hours over a 5 -minute period. Overpressure protection for a blocked outlet at the scrubber is provided at the well sites. Page 2 of 6 INLET MEASUREMENT The inlet measurement will be designed to have a capacity of 160 MMSCFD. The type of measurement element to be employed is a clamp -on ultrasonic meter. No continuous gas analysis of any kind is required in the inlet measurement system. The measurement is not for custody transfer, but the accuracy should be consistent with the commercially available measurement equipment. The output of this measurement device is both local and remote flow indication with EFM data accumulation. The EFM device must communicate to a radio that transmits the data to the Williams SCADA network. GAS COMPRESSION The gas compression system will initially consist of two (2) Caterpillar 3612/Ariel JGZ-4 compressor/engine packages. The station will be designed and laid out to expand to four compressor units at a later date. There will be two stages of compression per compressor unit. The physical layout will be similar to the existing design at the Parachute Creek facility to the extent possible. Air permits for this expansion have been applied for from the Colorado Department of Public Health and Environment. Please see these applications in Tab 7. Interstage cooling will be required between the two stages of compression. The intercooler bundles will be incorporated into a common bay of an electric -drive air- cooled heat exchanger. The gas aftercooler bundles will be incorporated into a separate bay of an electric -drive air-cooled heat exchanger. The engine coolers will be separate from the gas coolers and will also be electric motor drive. The maximum design dry bulb air temperature is 110°F. There will be one intercooler bay and one aftercooler bay installed initially with capability to expand for the third and fourth units. Space will be provided for the coolers for the third and fourth unit. Important Note: Via this application to Garfield County, we are applying for approval for the expansion of the compressor building at both Webster Hill and Rabbit Brush Compressor Stations to a maximum size of 75'-0" wide x 275'-0" long. This would allow for the building/compressor expansion to occur without further Garfield County land use approvals. A Garfield County building permit would, of course, need to be applied for and obtained. Page 3 of 6 GAS DEHYDRATION The gas dehydration system will be a Tri -Ethylene Glycol (TEG) system with an initial capacity of 80 MMSCFD, expandable to 160 MMSCFD with the addition of a second train as a separate expansion project. The purpose of installing the gas dehydration system is to prevent hydrate formation and/or freezing in the downstream pipelines. The moisture specification for all times of the year is 5 lbs water per MMSCFD and the design gas inlet temperature is 120°F. The inlet gas to the dehydration system must be conditioned with coalescer-type separation with I micron droplet size. TEG REGENERATION The TEG regeneration system will be sized for the initial load of 80 MMSCFD and will employ controls on the still overhead stream to maintain the BTEX (Benzene, Toluene, Ethyl Benzene and Xylene) at acceptable levels in the non -condensable stream. The system will be expandable to 160 MMSCFD with the addition of a second train as a separate expansion project. The still overhead condenser will be designed with air recirculation capability to prevent freezing during cold weather. Pumps and air-cooled heat exchangers will be electric motor driven. DISCHARGE GAS MEASUREMENT The discharge gas measurement system will be designed to have a capacity of 160 MMSCFD. The type of measurement element to be employed is a clamp -on ultrasonic meter. No continuous gas analysis of any kind is required in the inlet measurement system. The measurement is not for custody transfer, but the accuracy should be consistent with the commercially available measurement equipment. The output of this measurement device is both local and remote flow indication with EFM data accumulation. Continuous moisture content monitoring is also required in the discharge gas measurement system. The EFM device must communicate to a radio that transmits the data to the Williams SCADA network. VAPOR RECOVERY SYSTEM Glycol still overhead vapors, glycol flash tank vapors and condensate flash tank vapors will be compressed by a vapor recovery system and re -introduced into the main gas piping upstream of the inlet gas scrubber. The vapor recovery system will be designed for the full build -out of 160 MMSCFD. The system must be capable of operating acceptably from 35 MMSCFD to 160 MMSCFD facility throughput range. The compressor will be driven by electric motor drives and the oil cooler will be electric motor drive. CONDENSATE FLASH AND STORAGE Produced condensate will be flashed to 20 psig in the Condensate Flash Tank prior to being routed to the storage tanks. The flashed vapors will be collected in the Vapor Recovery System. The liquids from the Condensate Flash Tank will be routed to the Condensate Storage Tanks. There will be three 400 bbl Condensate Storage Tanks for storage of produced hydrocarbon liquids at 4 oz/in2 (commonly referred to as atmospheric storage). Page 4 of 6 FUEL GAS CONDITIONING The fuel gas conditioning system will be designed for the full build -out of 160 MMSCFD. The system must be capable of operating acceptably from 35 MMSCFD to 160 MMSCFD facility throughput range. The source of fuel gas will be on the inlet of the facility on the downstream side of the Inlet Separator where clean, dry gas is available to start the compressors and run the standby generator. The fuel gas will be heated above the hydrocarbon dew point by injecting a controlled stream of hot gas from the 1 S' stage compressor discharge. A fuel gas scrubber will be provided to filter the gas to 0.3 microns. BUILDING SYSTEMS Compressor Building: Building Type: A pre-engineered, rigid framed metal building is provided to house the engine - compressors and other related equipment. Ample space is allocated around the engine -compressors for access and maintenance. The building has one bay for work area and is designed to allow for future expansion. HVAC: Ventilation design for the compressor building shall provide for the design peak summer condition to maintain 125°F with the engine -compressors running and the outside ambient temperature of 110°F (temperature difference = 15°F). No additional heating, cooling or air conditioning is provided. Important Note: Via this application to Garfield County, we are applying for approval for the expansion of the compressor building at both Webster Hill and Rabbit Brush Compressor Stations to a maximum size of 75'-0" wide x 275'-0" long. This would allow for the building/compressor expansion to occur without further Garfield County land use approvals. A Garfield County building permit would, of course, need to be applied for and obtained. MCC/Control Building: Building Type: A pre-engineered, rigid frame metal building is provided to house the facility controls, MCC, air compressor system, generator and other related equipment. Ample space is allocated around the equipment for access and maintenance. HVAC: In the finished area of the MCC/control building, the cooling and heating shall be provided by a refrigeration type air conditioning and a forced air, gas furnace system. Heating for the unfinished area shall be by gas fired, unit space heaters. Cooling is not required in this area. Important Note: Via this application to Garfield County, we are applying for approval for the expansion of the MCC/Control building at both Webster Hill and Rabbit Brush Compressor Stations to a maximum size of 50'-0" wide x 125'-0" long. This would allow for the compressor station expansion to occur without further Garfield County land use approvals. A Page 5 of 6 Garfield County building permit would, of course, need to be applied for and obtained. Please contact me with any questions. Sincerely, Philip B. Vaughan President PVCMI Page 6 of 6 8 I I - 0 I °. J - 1 1 D _ C A 417.65" 8 8 14 60+00 W 71 W IJ W W W W _ W 8. W _ W 71 - - GATE lir . 3'-O" PERSONNEL ¢6 „,..6 4v N. 59+00 - PARCEL BOUNDARY _4 - ¢ j¢r9B ACtufi•Inas N 8'00'53" E.69905 '. _x— — —� �� I I �I.. -.sr T— r it r DOUBLE SWING GATE x FcncE� 32 ='- /,S DEEM ...30z4.' �$1 ItlV AWCY PMO ! IN66 I[u 1 P` _ - / _ .. N. CO:58+ 57+52 , _ - - - mew *NH a }�} Ea = fan MOO ADM ecus wan ( ER POINT NOTE @ TANK 2' A/C 95' RE80R) N. 609488.51' E. 1268029.82'. CO R IN RB- EM SECTION IN RB -CI -040.4 / I _ N. EL 5185.10' / CONTROL/ _ - i MCC BLDG V' R N 57+00 T- T _ 1 4' WEE SIDEWALK , - LIMIT 3' CRUSHED OFSURFACING (YP) ROCK •- - 11.1 _ S6AW .4Pw6oaaanal¢ 1 aVx -MNP�W ✓ ' u C- H /T(it M>`M 0 i-706 T66 e( o w. " . 0' `'+ '� W I 1 N. +67.25 I 58+00 . . . e • �. ' E 24+93.35tt .t N.. 66+3].6 �� 1 CONTAINMENT SECTIONd ON RB -CI -6405 I s:e' T76 n'_' \STAE t o r�" RABBIT BRUSH COMPRESSOR STATION- pO WI a ®. VICINITY MAP ,' ' N. 55+00 - 111 ON UDE: 38'28' LONGITUDE: 106'01' .. J'-0" PERSONNEL CATS • - - /TQC . - 3'-0". PEINDNNEL GATE J Fla A ACROSS PR.TACE VALLEY ' SIDEWALK FOR (RFV. DWG (3) _ L`IY LVYJ - II --I I: Yq " = illi ilii �a ' RD -CI RD -CI -6 -6403) _ Sl1LE N. 61+00 II \ -F%4NSKB4 (SEE. NOTE. 8) NN ISS 'I m s.a- _ a /, J h I GRAPHIC BCAIE • SIE N. 62+22 1.. E. 23+73 is am sma s 1 Doh - 60 n 52+00 J SEE NOTE pp4 B ON wR6Ntt 840505CIgN. TANK - I. 1 I1 1 NOTES: 51+00 > ® b ,.\ L� 1, .HORIZONTAL AND VERTICAL -CONTROL IS BASED ON SURVEY DATA PROVIDED BY D.R. ORIGEN AND ASSOCIATES. BASIS• OF BEARING FON GRID SYSTEM IS BASED ON A UNE BETWEEN -. CJI _ ,1 I IO Yn _ _ .` - - �\�_ ----\---' BENCH MARK BI AND B2. - 2. PARCEI. BOUNDARY BEARINGS SHANM PRE FROM TRUE NORTH. 3. ALL FOIINGIION ELEVATIONS ME BASED 64 PUNT COIX401NAE SYSTEM WnH TOP' of CONCRETE FOR THE COMPRESSOR BMLDMG PLANT 5173' 0 SED ON S148 O AT ELEVATION TO ACTUAL SU0-0" IS EQUAL 10 ACTUAL ELEVATION 51]3 0' BASED ON SURVEY3'HI DATA 4. a3' LINE 'AURA CFE SECONDARY AS CONTAINMENT s9? SOUX WRH LINER AND ACCESS STILE AS MANUFACTURED BY SKKIX. WCOMPANY, SIOUX PALLS, 30 OR APPROVED EQUAL. 8. GM NEW FENCE TO BE 6-O" HON OWN LARK. ALL 8. BRIDING AND DRAINAGE SHELL BE MODIFIED FOR FUTURE 0 FUTURE BUILDING -5120EKPANSION 48 T0RARE OF THATMINDEN LNE., THE FIRURE BVILDINO SIZE 6 SHOWN 014 F1A11'AS A HIDDEN LINE. �1 (SW CORNER POINT Y A/C 9E" REBME) N 10850195' EENCE `� .. I E 1251.69' 3' - �'jI FEL lair C - x - 24"SI6DE GTE 1( 50+000001AIHATES '-E 20+00. N. �� 3 a 4 ��� EL 78.69• ..a-� � JL. � � Y� 1L PAACEL .DART ttl .1.- l Y � iL�� SYS —T� —SV ,t .,j Stl9 Stl9 Stl9 SVD — S 3 88'06'28" W 889.88' Stl9 —Stl9 SV Stl9 Stl9 • 3'-0" PERSONNEL GTE w - —� PLAN yee DR4NiND NO, - TALE - REMSpNS' - REV1310NS - „ilia/� WI/8MS /(// - WTLLIAMS PRODUCTION RMT COMPANY 4 Z1•' L( > > ■ SGLE 1"e80'-0" MO DAY YR /yR� wn. ' - Harris �r""1' �'N' - ENERGY OMWN DJl 12/13/06 RB -CE -6402 CML -GRADING .& DRAINAGE PLAN-SHT 1 REV GTE BY PVD - DESCRIPTION REV DATE BY APP'D DESCRIPTION R9 -CI -6403 GN6.-ORAppO & DRAINAGE PLAN-ER.7 .. CHICO GB 02/15/07 APP'D ,IS 02)15/07 _ CIVIL SITE PLAN RE -GI -64O4 CML -0 DIND @roRAINAGE PLAN-SHT 3 RB -CI -6405 CML -GRADING AND DRAINAGE -MSC DETS APP'D APPROVED - •'9/07 4 RMT CO. RABBIT BRUSH . _ 1 51/91/b1 _ BB 15. REROUTED SIDEWALK, ADDED NOTE .@ STILES, READ. CONTAINMENT & SURFACING PROJECT 61060 DRAWING NUMBER RB—CI-6401. REV a 0 02/15/01 BB J5 ISSUE' FOR CONSTRUCTION REV DATE BY APP'S PRELININaM' ISSUE D C A 4'17'55' 8 6 5 4 3 2 . RB -CI -6403 0• ...__._.. - - — - -•�aa CURVE # A R E .. 1 45'00'00' LT 42.00' 3215' 32.99' r 1 4 -42.00 \ 32.99' _ 3 911.00103'15 1 ------ 3= _ 9000'00' LT 42.00 1 -/ F COMPRESSOR. 990000 RT ♦ 59.40' 6567' 6 ' ) 42.00' IT 65.97' 7 900000" RT I^ /I 5940' I \ \I� / 1 ' RLDG jja5N;54�30.___ 4200' r„ /15173�� `4 \\ / -St7 - / I'♦♦ II I 51]2.5, 5\TD' N " 1\ 0 / j .I -N, 64Far-ix \ ----'----_-- '_-- - /\I `♦\ • i i --,s1' --- li / / 1 -- / ♦�_'- 5 167 /_/ '. .., I J1. / ( \ _y_ i_I I J /1 // 1 - FENCE _ - I ♦ - i N. 53+00 T _ I--T2`"_CULVERT 516I I�END W/FLWEO xl q r/.J \ SECTIONS (40 LF INCLUDING END SECTS) xIl _ I .♦`\`�__ \-_ rII ___-_ 1 /I I I \ / -_ n N. 52]6.0 N LI �� , 1 \ \_ ----.__// _ \ /' \ IR / __ ___ - -- I 0 N. 5203.0 - \ \ / 11 ✓/ \ i xl -�\ I` / 1 • \ P4390 F V\\/ / ( [SUN) \♦ _ '___-_�. 1\\ // I1- x Y / PC CURVE i6\' •: I.0 - 1 16' END CULVERT W/FLARED SECTIONS (541F I. \ E i LO - 516 1 INCLUDING �--- END SECTS) .- 1\ 516 .-_ T` )x 51+00 -1 __-"______-_\\. \ 4 % •\♦- i/-- \ -- N. . i I \\ ♦ /� I. \\ I \ NV / NV EL 5157 5u 5159 -- ♦ i, xl - \ \ u • N // / 5156 5156.9+ , \ \ \\ \\ \\ \ \\ / - ------ _ -� /1 \ 1 _\ rINV `5166.5 '� Tom♦ EL ♦♦ / INV EL 51555 �-,. / /_y,I /•- � ®� -.----INV 5157.5 EL - I 4 I I 1 \ FENCE - 5156 - \ _-_ ®1 / 515 \ \ �1 __ I /--_ -� \I \\ kclTlU /I. T" ----__ \' ` ,l D A r / J I —// END 156; //J NX;EE5ROAD1/I 1 1' - �._ I \ /SB —� - 1 ( BEGN ROADA I \ \ \ / `, \ / 5158 16" CULVERT W/FIARED ,716" CULVERT W/FLAREO-� \ - B .. : IF �O \\ \ / �. — p gNvE.#6 --SPT CURVE /e -_' s 0 END SECTIONS (55 LF -- —7 END.SECTIONS (50 LE \\ INCLUDING END -SECTS)/ � \ `� \;. \, \ /^ —� _ l• 420 t, INCLUDING END. SECTS) / --z % 8 N. 50+00 ♦ ' x z %—' •ll f( % / x� % X % % — fir% % z x Tx ♦ _ r— „\.�\ y �� ~_ — I 14 _%_ 'IN/ EL 5158.0 / 6' STONE / RIP-RAPOYP' _ \ PARCEL�DARY - 66/ EL 5158 a ••> * 1 � - --�__ B 1tl�` 3'99-N • 544 - SVRI—S \ }—Stl9 EVD—Stl9 —SUB `_- Stl9—Stl9— SOD —SV9—/SVD—Stl9 SV9\\ \ SV9—Stl9 SVOL SV?' SVS { SV4— —Stl9! �-349-5y'D' \ - S ♦\ \\\ o\\ ♦\♦ \\♦ \. ill�, \ , ,/'' ��- I-- �– I 2 -TRACK R0A0 - W ♦ `,.--ACCESS-ROAD –' PT CURVE I(7 49'5.0 1 o I� E 25520 PI CURVE #7 • 8 n E.2 N CUTS t7 W W W W E2594.0 - CURVE DATA CURVE # A R T E .. 1 45'00'00' LT 42.00' 3215' 32.99' 2 456000" RT -42.00 3215 32.99' _ 3 911.00103'15 42.00 59.40' 65.97' 9000'00' LT 42.00 5940' 65.97' 5 990000 RT 42.00' 59.40' 6567' 6 990000' LT 42.00' 59.40' 65.97' 7 900000" RT 42.00' 5940' 65.97', 8 . 1500'06" LT 4200' 10.96' 11.00" LEGEND 0(ISTINC CONTOURS NEW CONTOURS – SWALE F.0Y1JNE GRAPHIC SCALE.. (MEMT ) 1 Ix1j - 90 M. NOTES 1. DNISN GRADE ELEVATIONS P340 CONTOURS ME TOP OF FINAL SURFACINO. 2. FINISH GR DE SHALL SLOPE AWAY FROM BUILDINGS AT 5% FOR A MINIMUM OF 10'-0'. 3. ALL CUT OR FILL SHALL NOT EXCEED 3H IV 4. PROVIDE SILT FENCE AND STRAW 9.41.E BARRIERS AS NECESSARY TO CONFROL EROSION DURING CONSTRUCTION.' 5. PROVIDE '-RIPRAP,-AS NECESSARY: AT CULVERT END SECTIONS. DRAWING NO. RB -C1-6301 RB -d-6401 R REVISIONS CMI-SONCWRFL'GEIERAL NOTES CML -SIZE PIAN REV DATE. BY OPT, DESCRIPI%N REV DATE' BY APP'D DESCRIPTION wens WILLIAMS PRODUCTION RMT. COMPANY • 1 BB �f ADDED & REV'D CONTOURS 0 ENO BB JS SSUED FOR CONSTRUCTION REV DATE BY APP D PRELIMINARY ISSUE SCALE DRAWN CHK'0 APP'D AFP'0. 0/1/80.,,, GB J5. r> DATE no .2 MD DAY YR 12/13/06 02/15/07 02/15/07 Harris Group Inc. ENERGY CIVIL GRADING & -DRAINAGE PLAN SHEET 1 WILUAMS PRODUCTION RMT CO. RABBIT BRUSH PROJECT 61060 DRAWING 'NUMBER RB -CI -6402 REVA 7 6 5 4 3 2 1 B AIAICMLNE N. 54+ ELAN GRAPHIC SCALE' (18 FET) 1 lues =.30 It NOTES: 1. FOR NOTES. LEGEND AND CU DRAWING RB -01-6402. DATA SEE -DRAWING NO, • REV610NS REVISIONS CML -GRADING MODRAINAGERAN-SIR 1 REV DATE BY DESCRIPTION DATE BY APP'D DES CRIPDON Wien %LUAMS PRODUCTION RMT COMPANY 1 03Pla BB (a ADDED & REV'D CONTOURS 0 52/51N BB JS ISSUED FOR CONSTRUCTION DATE APP'D PREIJMINARY ISSUE SCALE DRAWN ON8'D APP'D 0.31/58 GB. J5 MO DAY YF 12/13/06 02/15/07 02/15/07 PFFD PPPROVEO Harris Group Inc. ENERGY CIVIL GRADING & DRAINAGE PLAN SHEET 2. DATE 3/7/07 PROJECT 81060 WILLIAMS PRODUCTION RMT CO. - RABBIT BRUSH DRAWING. NUMBER RB -CI -6403 REVA QS. ROAD �_' �� 8 4 W W BEGIN ACCESS ROAD -2 N. 5928.5' \\ i \ I \ \ - \ �-� - —'s\— �_ U ��x- / \ \ I \ BOUNDARY., _ PARCEL BOUNDARY \ ` Ills-� '. ,. x.' --x z -___, FENCE .kms x - ��_ \� x x 8 z x x z �x x --4- 11 \ __s--�-8. FC CURVE g1 /j _- - -- _ - 51B't - `E - - //I % / I II \\ I 1 \\1 I 1 /� �. I I / -. \ // '//// / / PF�a1RVE'p1 �/�d/ 1 \ - ENbD6BBACCESS ROAD x '' E2862.0 ����. C1 jf \\ ___ PC CURVE/2 Z.. I1 �� i-‘=,. 3 -_�ROAOA \ - . �e�� F1 CURVE g2VP1! WHVE g2II ]21 .: .. =.. f I \\FENL\W / �� N 3]380(7 \\ . CONTROL/ / / -'___-- iii \-�� R CURVE g3 .0 �� ,_ ::, `{9. -' ,,� i� C�FF=5181'-B� \ MCC BLCO / / 1 / \ - 6180/-' : I N. 20.77.0 x T -mac -ROAD A \ � 5161 1 --___-5180----_-- //. .\__-_ `\ 12 D' it , 'I N bB87.0-�-IIOSw //� _``I I\\ .----� • -Ia - J q / \\ 0 5178.50 o, / / �• i \\ - ,.• `Jr• / % - \\ / / / 24' 0' \ N. :56+00 {I/ ___- I_ - .- ______ PC DANE g4_ I / - / / / /II{/,/ 502 /�/ //./ / \ . \ `I_ \ '1 \ • \`- \`♦I _______ — I I `\ 61]3.60 I 1 PC WRVS gs - / h \ It I 1 . _ ___ \ 0 / / \J - R CU RJE !JS / 5172- .I\A 1. \I---- b�2Z0 . q .TB, �- - .. ._; -__�__..___,_-_- N.55+00 i/,E NT EpJ' ; 1 - n 1\ - PT ICURYE 15% 0 - M� ROAD.. - A ., 5480 2232.0N / x \\ �'/1 51]3 h ..../ \\ 5172.5. I }510. '� / / // / / f \ II R CURVE i4 PT CARVE g4' \��'� / / - / \\ iP\' - •T].0 x _ % . j - COMPRESSOR BLDG ■ / 1 \/ I II FF=51]3'-0' N. 58+15 __ \-_J - I TOAD 01 ,1 -,� 11 �. --*j7 AIAICMLNE N. 54+ ELAN GRAPHIC SCALE' (18 FET) 1 lues =.30 It NOTES: 1. FOR NOTES. LEGEND AND CU DRAWING RB -01-6402. DATA SEE -DRAWING NO, • REV610NS REVISIONS CML -GRADING MODRAINAGERAN-SIR 1 REV DATE BY DESCRIPTION DATE BY APP'D DES CRIPDON Wien %LUAMS PRODUCTION RMT COMPANY 1 03Pla BB (a ADDED & REV'D CONTOURS 0 52/51N BB JS ISSUED FOR CONSTRUCTION DATE APP'D PREIJMINARY ISSUE SCALE DRAWN ON8'D APP'D 0.31/58 GB. J5 MO DAY YF 12/13/06 02/15/07 02/15/07 PFFD PPPROVEO Harris Group Inc. ENERGY CIVIL GRADING & DRAINAGE PLAN SHEET 2. DATE 3/7/07 PROJECT 81060 WILLIAMS PRODUCTION RMT CO. - RABBIT BRUSH DRAWING. NUMBER RB -CI -6403 REVA 8 7 8 5 3 2 1 D C B A 1\\ W - ' 5150`/ II I _ W kl W W W W - N. 51+00 -\ 1 ij .\`I �G 12^ \\ N. 50400 / r -^A \ A A / PT CURVEIB MCMM/B PO CURVE Ie, . • .. E 1 -/ f�. i.: BEGINACCE04 ROAD 1 h`. \ �\ pp � 162 \ •- �_ t lCCE35 ROADI 1 - - Q . N. 40+00 q 1.055 ELM ORAPipC BONS • 'Imnye ) mm=90 n. NOTES. 1. FOR NOTES, LEGEND ROD CURVE DATA SEE DRAW90 RB -CI -0402. DRAWING PD. RS -CI -6402 REVISIONS CML-DRADBIO AND DRAFUGE RAH-SHT 1 REV BY PPYD DATE BY. APYO DESCRIPTION Will ams WILLIAMS. PRODUCTION RMT' COMPANY 0 00_Wee ./J ,ISSUED FON CONBIRUC REE DAIS. By PPP'0 PRELIM/Jr( ISSUE WALE DRAM. CNMD PPP'0 D1/ 410 DAY TRW 12 13/00 Sirs/01 Harris Croup Inc. ENERGY ✓J NYO ¥f/P/ APPROVED • GRADING 8i •DRAINAGE PLAN SHEET 3 DATE al rp7 WILLIAMS PRWUCIIDY RIR CO. Reser! BRUSH. PROJECT 81000 DRAWN. NUMBER RB -CI -6404 IRDI N 8 t 1 0 8 7 6 5 4 2 SILT FENCE DFIAII STRAW BALE BARRIER DETAIL EROSION CONTROL DETAILS TYPICAL TANK CONTAINMENT SECTION SUBGMDE TYP-SIDEWALK CROSS SECTION MANSYERSENC0(DMRD. JOINTS SHALL BE TRANNS'ERSASE E*WI MORE JOINTS BE PLACED AT MOT LORE ITIAN 60' INTERVALS. PROVIDE EXPANSION MINTS SEIMEEN SIDEWALKS AND -DOOR 'STOOPS, KIDDER PADS. ETC. SACKFUL WITH LOW PERMEABLE MATERIAL COMPACT TO 95R MOD. PROCTOR DENSOY VAC b.Ace ,1/4/442. T7 tf t y/094 "i` PIPE SMO/GRAVELD BEAN N TYPICAL PIPE TRENCH DETAIL RDA° 2 LNOPE PLANS 8' COMPACT ROAD BASE 2% SLOPE (MN) AS RE00- EE PUNS DRAWING 2 RB -C1-6402. RD -C1-6403 :RB -CI -8404 PENSIONS WL GRAMNM AND BRANAGE.PLNI-SHT ,. CML-CFAD60 PND DRAINAGE PVN -SVT 2 CML -GRADING PND'. DRAINAGE PLAN-SHT DATE 6Y APP.!) sr APPT 12 WARMED & COMPACTED SUBGRADE TYPICAL ROAD SECTION wias GEOIEATLE FABRIC WIWAMS PRODUCTION RMT COMPANY an �J ISSUED FOR 'CONSTRUCTION -. DATE or APP. UE SCALE DRAWN CHKT AS_NOTF0 BO 45 'PRI) ARAN MO DAY YR 0142640/ Ltf/Z Harris Group Inc. ENERGY APPRIWED ear A..4t DATE PROJECT 61060 CIVIL GRADING AND DRAINAGE . MISCELLANEOUS DETAILS WILLIAMS PRODUCTION AMT- CO. 'war ERIWI DRAWING NUMBER - -REV. RB -CI -6405 S Geotechnical I'ngineering Group, Inc. GEOTECHNICAL. INVESTIGATION Rabbit Brush Compressor Station Garfield County, Colorado Prepared For: Williams Production RMT Company P.O. Box 370 Parachute, CO 81635 Attention: Tom Fiore Job No. 2,526 December 15, 2006 Geotechnical, Environmental and Materials Testing Consultants Grand Junction - Montrose - Moab - Crested Butte (970) 245-4078 • fax (970) 245-7115 • geotechnicalgroup.com 2308 Interstate Avenue, Grand Junction, Colorado 81505 TABLE OF CONTENTS SCOPE 1 SUMMARY OF CONCLUSIONS 1 SITE CONDITIONS 2 PROPOSED CONSTRUCTION 3 SUBSURFACE CONDITIONS 3 SITE DEVELOPMENT 4 SEISMIC CONSIDERATIONS 5 FOUNDATIONS 6 SPREAD FOOTINGS- STRUCTURES SENSITIVE To MOVEMENT 7 SPREAD FOOTINGS- STRUCTURES WHERE MORE RISK OF MOVEMENT IS ACCEPTABLE 8 REINFORCED MAT FOUNDATIONS -WHERE MORE RISK OF MOVEMENT IS ACCEPTABLE 9 FLOOR SYSTEMS 10 BELOW -GRADE CONSTRUCTION 12 CONCRETE 12 SURFACE DRAINAGE 13 CONSTRUCTION MONITORING 14 LIMITATIONS 15 FIG. 1 - VICINITY MAP FIG. 2 - LOCATION OF EXPLORATORY BORINGS FIG. 3 - LEGEND AND NOTES OF EXPLORATORY BORINGS FIGS. 4 THROUGH 10 - LOGS OF EXPLORATORY BORINGS FIGS. 11 THROUGH 15 - SWELL CONSOLIDATION TEST RESULTS FIG. 16 - DIRECT SHEAR TEST RESULTS TABLE I - SUMMARY OF LABORATORY TEST RESULTS APPENDIX A - SAMPLE SITE GRADING SPECIFICATIONS SCOPE This report presents the results of our Geotechnical Investigation for the proposed Rabbit Brush, compressor station in Garfield County, Colorado. Our investigation was conducted to explore subsurface conditions and provide foundation design recommendations for the anticipated construction. The report includes descriptions of subsoil and groundwater conditions found in seven exploratory borings made during this investigation, recommended foundation systems, allowable design soil pressures and design and construction criteria for details influenced by the subsurface conditions. The report was prepared from data developed during field exploration, laboratory testing, engineering analysis and experience with similar conditions. A brief summary of our conclusions and recommendations follows. Detailed criteria are presented within the report. SUMMARY OF CONCLUSIONS 1. Subsoils found in the exploratory borings consisted generally of sandy, silty clay underlain by variable sandy, clayey gravel to the maximum depth explored of 20 to 25 feet. Groundwater was not encountered on the day of drilling. 2. Medium stiff to very stiff, sandy, silty clay, materials were identified at foundation levels We recommend structures that cannot tolerate movement be installed on drilled piers bedded in an underlying competent strata to help reduce potential movement of structures. A competent stratum was not identified in any of the test borings at the time of our Rabbit Brush Compressor Station Garfield County, Colorado GEG Job No. 2,526 1 investigation. We recommend that additional borings be performed to find a competent strata for structures that are sensitive to movement. A recommendation for shallow foundations supported by well -compacted engineered structural fill is presented for structures where more risk of potential movement is acceptable. A discussion of alternatives, including detailed design and construction criteria are included in the text of the report. 3. We believe slab -on -grade construction supported by the soil encountered will involve significant amount of movement. We recommend structurally supported floors in all finished areas. Detailed design and construction criteria area presented in the text of this report. 4. Surface drainage should be designed for rapid runoff of surface water away from the proposed structures. SITE CONDITIONS The subject site was located in Section 32, Township 6 South, Range 94 West in Garfield County, Colorado as shown on Fig.1. The subject site was relatively flat with native vegetation covering the site. Vacant BLM land was, east, south and west of the site. The Roan cliffs are north of the site. The subject site slopes down from north to south at an inclination of approximately 5 to 10 percent (measured with handheld rangefinder and hand level). Rabbit Brush Compressor Station Garfield County, Colorado GEG Job No. 2,526 2 PROPOSED CONSTRUCTION We understand proposed construction will consist of a petroleum compressor station. There will be various compressor pads, compressor building, pipe racks, related structures including skid mounted structures. There will be no below grade construction. If proposed construction changes or is different from what is stated, we should be contacted to review actual construction and our recommendations. SUBSURFACE CONDITIONS Subsurface conditions at the site were investigated by drilling and sampling seven exploratory borings. Locations of the exploratory borings are shown on Fig. 2. Graphic logs of the soils found in the borings and field penetration resistance tests are presented on Figs. 4 through 10. Subsurface conditions encountered in TH- 1 through TH-5 and in TH-7 included sandy, silty clay to the maximum depth explored of 20 to 25 feet. The sandy, silty clay, to slightly gravelly sand in TH-6 was underlain by sandy, clayey gravel material from a depth of about 19 feet to the maximum depth of the boring of 20 feet. The sandy, silty clay was medium stiff to very stiff, moist, and brown. The gravelly, clayey sand to sandy, clayey gravel was medium dense to very dense, moist and brown. Rabbit Brush Compressor Station Garfield County, Colorado GEG Job No. 2,526 3 Ten sandy, silty, clay samples tested had moisture content ranging from 4.3 to 13.8 percent and seven of the samples had dry densities ranging from 90 to 130 pcf. Three sandy, silty clay samples were tested for Atterberg Limits. The samples exhibited liquid limits of 27 to 34, and plasticity indexes of 14 to 22 and 81 to 84 percent passing the No. 200 sieve (silt and clay sized particles). Five sandy, silty clay samples were tested for swell consolidation characteristics using a one-dimensional oedometer apparatus. The samples exhibited 2.7 percent consolidation to 6.9 percent swell when wetted under a confining pressure of 250 to 1,000 psf with estimated swell pressures ranging from 800 to 3,500 psf. One sandy, silty clay sample tested exhibited a cohesion of 200 psf and an internal angle of friction of 22 degrees. Two sandy, silty clay samples were tested for water soluble sulfates. The samples had 400 and 670 ppm water soluble sulfates. Results of laboratory testing are presented on Fig. 11 through 16 and summarized on Tables I. SITE DEVELOPMENT The surface in areas to receive fill or support structures should be scarified to a depth of 10 inches, moisture conditioned to 2 to 4 percent wet of optimum moisture content and compacted to at least 95 percent of standard Proctor (ASTM D 698) maximum dry density. On-site soils free of deleterious materials, organics and particles Rabbit Brush Compressor Station Garfield County, Colorado GEG Job No. 2,526 4 over 6 -inches diameter can be reused in non-structural areas during grading. Fill in structural areas may include special requirements as discussed later under the "FOUNDATIONS" section of this report. Additional fill placement should be moisture conditioned to 2 to 4 percent wet of optimum moisture content and compacted to at least 95 percent of standard Proctor (ASTM D698) maximum dry density in 10 -inch maximum thickness loose lifts. Subgrade soils and fill greater than 10 foot in depth should be moisture conditioned to 2 to 4 percent of optimum moisture and compacted to at least 100 percent maximum dry density standard Proctor (ASTM D698). Subgrade preparation, and placement and compaction of grading fill should be observed and tested by a representative of our firm during construction. Sample site grading specifications are included in Appendix A. SEISMIC CONSIDERATIONS Foundation and floor systems include structural support from the surficial sandy, silty clay soils. Based on 2000 UBC we believe the site is located in Seismic Zone 1. Based on our understanding of proposed construction and subsurface conditions, we suggest a "Site Class D" be used for foundation seismic design as described in 2000 IBC. Based on the field and laboratory results we suggest a shear modulus of 4 ksi. Rabbit Brush Compressor Station Garfield County, Colorado GEG Job No. 2,526 5 FOUNDATIONS This investigation indicates subsurface conditions at foundation levels generally consist of sandy and silty clay with significant swell potential. In our opinion, a foundation to better help mitigate risk of potential movement should be anchored below the zone of probable moisture variation and concentrate the weight of the structure to resist potential swell of the sandy, silty clay. In our opinion, a straight shaft drilled pier foundation or a driven pile foundation bedded in an underlying competent stratum most nearly satisfies these criteria. A competent bearing strata was not encountered in the exploratory test borings to the maximum depth explored of 25 feet. Additional subsurface exploration would be necessary to identify a bearing stratum and provide design and construction recommendations for deep foundations. If the owner and builder accept the risk of significant foundation movement and associate damage the structures may be supported on spread footings or reinforced mat foundations. We present design and construction criteria for spread footings with recommendations to help reduce or mask the influence of soil volume changes for structures sensitive to movement and spread footing and reinforced mat foundations for structures where significant movement is acceptable. These criteria were developed from analysis of field and laboratory data and our experience. The additional requirements (if any) of the structural engineer should also be considered. Rabbit Brush Compressor Station Garfield County, Colorado GEG Job No. 2,526 6 Spread Footings- Structures Sensitive To Movement 1. Bottom of footing should have a separation of at least 6 feet from the onsite sandy, silty clay. The clay samples tested had swell pressures up to about 3,500 psf. If the clay becomes wetted it may swell with these pressures. It if very difficult to provide adequate separation from material with swell pressures in this range to completely eliminate the influences of the swell pressures. The recommended 6 feet separation between the bottom of the footings and the top of the clay is intended to help reduce or mask the influence soil volume changes. 2. Existing soils should be removed to at least a depth of 6 feet below and 6. feet horizontally beyond footings in each direction and replaced with a well - compacted engineered structural fill. The resulting subgrade should be prepared by scarifying 10 -inches, moisture conditioning to 2 to 4 percent wet of optimum moisture content and compacting to at least 95 percent of standard Proctor (ASTM D698) maximum dry density. Structural fill soils should consist of non -expansive well graded sands and gravels with a maximum particle size of 1'A -inches, maximum 15 percent passing the No. 200 sieve and maximum liquid limit of 30. A CDOT type Class 5 aggregate base course would meet this criteria and is recommended. A sample of the proposed fill soils should be supplied to our office for acceptance testing, prior to use or import. Structural fill should be moisture conditioned to within 2 percent of optimum moisture content and compacted to at least 95 percent of standard Proctor (ASTM D698) maximum dry density in 10 -inch maximum loose lifts. 3. Footings bearing on well -compacted structural fill placed as stated above should be designed for a maximum soils bearing pressure of 2,500 psf. Footing should be designed with a minimum dead load as high as possible. Loose soils should be completely removed from foundation bearing areas, prior to placing concrete. 4. We recommend a minimum width of at least 18 -inches for continuous footings. Isolated pads should be at least 36 inches by 36 inches. Foundation walls should be well -reinforced top and bottom. We recommend reinforcement sufficient to span an unsupported distance of at least 15 feet. Reinforcement should be designed by the structural engineer. Rabbit Brush Compressor Station Garfield County, Colorado GEG Job No. 2,526 7 5. Based on a design soil bearing pressure of 2,500 psf, a footing width of about 18 inches and footings placed on a 6 feet thick layer of well compacted structural fill the estimated differential movement is less than about 1/2 inch. If wider footings are used we should be contacted to review the estimated settlement and provide additional recommendations where needed. 6. Exterior walls should be protected from freezing. Refer to local building code for details. 7. The completed foundation excavation should be observed by our representative for proof roll and to verify the foundation subgrade conditions are as anticipated from our exploratory borings. Geotechnical Engineering Group, Inc. should also be called to test compaction of subgrade and fill during placement. Spread Footings- Structures Where More Risk of Movement is Acceptable 1. The Bottom of footing should have a separation of at least 2 feet from the onsite sandy, silty clay. The clay samples tested had swell pressures up to about 3,500 psf. If the clay becomes wetted it may swell with these pressures. It if very difficult to provide adequate separation from material with swell pressures in this range to completely eliminate the influences of the swell pressures. The recommended 2 feet separation between the bottom of the footings and the top of the clay is intended to only help mask soil volume changes. 2. Existing soils should be removed to at least a depth of 2 feet below and 2. feet horizontally beyond footings in each direction and replaced with a well - compacted structural fill. The resulting subgrade should be prepared by scarifying 10 -inches, moisture conditioning to 2 to 4 percent wet of optimum moisture content and compacting to at least 95 percent of standard Proctor (ASTM D698) maximum dry density. Structural fill soils should consist of non- expansive well graded sands and gravels with a maximum particle size of 1% -inches, maximum 15 percent passing the No. 200 sieve and maximum liquid limit of 30. A CDOT type Class 5 aggregate base course would meet this criteria and is recommended. A sample of the proposed fill soils should be supplied to our office for acceptance testing, prior to use or Rabbit Brush Compressor Station Garfield County, Colorado GEG Job No. 2,526 8 import. Structural fill should be moisture conditioned to within 2 percent of optimum moisture content and compacted to at least 95 percent of standard Proctor (ASTM D698) maximum dry density in 10 -inch maximum loose lifts. 3. Footings bearing on at least 2 feet of well -compacted structural fill placed as stated above should be designed for a maximum soils bearing pressure of 1,500 psf. Footing should be designed with a minimum dead load as high as possible. Loose soils should be completely removed from foundation bearing areas, prior to placing concrete. 4. We recommend a minimum width of at least 18 -inches for continuous footings. Isolated pads should be at least 36 inches by 36 inches. Foundation walls should be well -reinforced top and bottom. We recommend reinforcement sufficient to span an unsupported distance of at least 15 feet. Reinforcement should be designed by the structural engineer. 5. Based on a design soil bearing pressure of 1,500 psf, a footing width of about 18 inches and footings placed on a 2 feet thick layer of well compacted structural fill the estimated differential movement is about 2 to 4 inches. If wider footings are used we should be contacted to review the estimated settlement and provide additional recommendations where needed. 6. Exterior walls should be protected from freezing. Refer to local building code for details. 7. The completed foundation excavation should be observed by our representative for proof roll and to verify the subsurface foundation conditions are as anticipated from our exploratory borings. Geotechnical Engineering Group should also be called to test compaction of subgrade and fill during placement. Reinforced Mat Foundations —Where More Risk of Movement is Acceptable 1. Reinforced mat foundations can be designed for a maximum soil bearing pressure of 1,500 psf. When supported on a minimum 2 feet thick well compacted structural fill. Loose soils should be completely removed from Rabbit Brush Compressor Station Garfield County, Colorado GEG Job No. 2,526 9 foundation bearing areas, prior to placing structural fill or foundation concrete. 2. Existing soils should be removed to at least a depth of 2 feet below and 2 feet horizontally beyond the mat in each direction and replaced with a well - compacted structural fill. The resulting subgrade should be prepared by scarifying 10 -inches, moisture conditioning to 2 to 4 percent wet of optimum moisture and compacting to at least 95 percent of standard Proctor (ASTM D698) maximum dry density. Structural fill soils should consist of well graded sands and gravels with a maximum particle size of 1'/2 -inches, maximum 15 percent passing the No. 200 sieve and maximum liquid limit of 30. A CDOT type Class 5 aggregate base course would meet this criteria and is recommended for structures where mitigating potential movement is a concern. A sample of the proposed fill soils should be supplied to our office for acceptance testing, prior to use or import. Additional fill should be moisture conditioned to within 2 percent of optimum moisture content and compacted to at least 95 percent of standard Proctor (ASTM D698) maximum dry density in 10 -inch maximum loose lifts. 3. Mat foundations should be well reinforced, both top and bottom. We recommend reinforcement sufficient to span an unsupported distance of at least 12 feet and to distribute lodes over entire mat. Reinforcement should be designed by the structural engineer. 4. Foundations should be protected from freezing. Refer to local building code for details. 5. The completed foundation excavation should be observed by our representative to verify subsurface foundation conditions are as anticipated from our borings and to test compaction. FLOOR SYSTEMS The near -surface soils which will support slab -on -grade floors exhibited significant movement potential. Some movement must be assumed. To our knowledge, the only reliable solution to control floor movement is the construction of floors supported by the Rabbit Brush Compressor Station Garfield County, Colorado GEG Job No. 2,626 10 foundation system over a minimum 12 inch void. In our opinion, drilled piers should be used in all foundation areas. If the owner and builder accept the risk of significant movement and associated damage, the floors may be constructed as slab on grade floors. The owner is cautioned that future maintenance of any slabs on grade may include the removal and replacement of the slabs. We recommend the following precautions for construction of slabs -on -grade at this site. These precautions will not prevent movement in the event the underlying conditions become wetted; they tend to reduce damage if movement occurs. 1. Slabs should be supported by at least a 2 foot depth of well compacted, structural fill as stated above under the "FOUNDATIONS, Spread Footings" section of this report. The completed subgrade should be scarified 10 -inches depth, moisture conditioned to within 2 percent of optimum moisture content and compacted to at least 95 percent of maximum standard Proctor (ASTM D698) dry density, prior to structural fill placement. A Geotechnical Engineering Group, Inc. representative should be called to visit the site to test compaction and observe soils in the excavation bottom and structural fill. 2. Slab -on -grade construction should be limited to unfinished areas and exterior flatwork where practical. 3. Slabs should be separated from exterior walls and interior bearing members with a slip joint which allows for free vertical movement of slabs. 4. The use of slab -bearing partitions should be minimized. Where such partitions are necessary, a slip joint allowing at least 6 inches of free vertical slab movement should be used. Doorways and stairwells should also be designed for this movement. Rabbit Brush Compressor Station Garfield County, Colorado GEG Job No. 2,526 11 5. Underslab plumbing should be eliminated where feasible. Where such plumbing is unavoidable, it should be thoroughly pressure tested during construction for leaks and should be provided with flexible couplings. Plumbing extending through slab on grade floors should be separated from floor slab to allow independent movement. 6. Frequent control joints should be provided to reduce problems associated with shrinkage and curling. The American Concrete Institute (ACI) and Portland Cement Association (PCA) recommend a maximum panel size of 8 to 15 feet depending upon concrete thickness and slump, and the maximum aggregate size. We advocate additional control joints 3 feet off and parallel to grade beams and foundation walls. BELOW -GRADE CONSTRUCTION No below -grade construction is anticipated at this site. Typically, building foundation drains are not required for construction of this type. Crawl space, if any, in building areas should be sloped so that potential moisture will not collect in these areas, but flow out of the crawl space. Crawl space areas should also be well ventilated to reduce potential humidity and musty odors. CONCRETE Two samples (TH- 1 and TH-7 at 1-4 feet) were tested for water soluble sulfate concentrations. The test results indicate a water soluble sulfate concentration of 400 to Rabbit Brush Compressor Station Garfield County, Colorado GEG Job No. 2,526 12 670 ppm. Concentrations in this area have been shown to have a moderate effect on concrete that comes into contact with the soils. We recommend a Type II (sulfate resistant) cement be used for concrete that comes into contact with the subsoils. In addition, concrete should have a maximum water -cement ratio of 0.50. SURFACE DRAINAGE Performance of foundations and concrete flatwork is influenced by surface moisture conditions. The site formational claystone has significant swell potential. The swell potential typically is mobilized by wetting. Reducing the potential for moisture migration into the site soil and formational claystone with reduce the risk of mobilization of swell potential of site materials. Risk of wetting foundation soils can be reduced by carefully planned and maintained surface drainage. Surface drainage should be designed to provide rapid runoff of surface water away from the proposed structures. We recommend the following precautions be observed during construction and maintained at all time after the construction is completed. 1. The ground surface surrounding the exterior of the structures should be sloped to drain away from the additions in all directions. We recommend a slope of at least 12 inches in the first 10 feet around the structures, where possible. In no case should the slope be less than 6 inches in the first 5 feet. The ground surface should be sloped so that water will not pond adjacent to the additions. Rabbh Brush Compressor Station Garfield County, Colorado GEG Job No. 2,526 13 2. Backfill around foundation walls should be moistened and compacted. 3. Roof downspouts and drains should discharge well beyond the limits of all backfill. Splash blocks and downspout extenders should be provided at all discharge points. 4. Landscaping, if any, should be carefully designed to minimize irrigation. Plants used close to foundations should be limited to those with low moisture requirements; irrigated grass should not be located within 5 feet of the foundation. Sprinklers should not discharge within 5 feet of foundations. Irrigation should be limited to the minimum amount sufficient to maintain vegetation; application of more water will increase likelihood of slab and foundation movements. 5. Impervious plastic membranes should not be used to cover the ground surface immediately surrounding the structures. These membranes tend to trap moisture and prevent normal evaporation from occurring. Geotextile fabrics can be used to limit the weed growth and allow for evaporation. CONSTRUCTION MONITORING Geotechnical Engineering Group, Inc. should be retained to provide general review of construction plans for compliance with our recommendations. Geotechnical Engineering Group, Inc. should be retained to provide construction -monitoring services during all earthwork and foundation construction phases of the work. This is to observe the construction with respect to the geotechnical recommendations, to enable design changes in the event that subsurface conditions differ from those anticipated prior to start of construction and to give the owner a greater degree of confidence that the additions are constructed in accordance with the geotechnical recommendations Rabbit Brush Compressor Station Garfield County, Colorado GEG Job No. 2,526 14 LIMITATIONS The scope of services for this study does not include any environmental or biological (such as radon, mold, fungi, bacteria, etc.) assessment of the site or identification or prevention of pollutants or hazardous materials conditions. If the owner is concerned about the potential for such contamination or pollution, other studies should be performed. Seven exploratory borings were drilled in the proposed structure areas. The exploratory borings are representative of conditions encountered only at the exact boring locations. Variations in the subsoil conditions not indicated by the borings are always possible. Our representative should observe open foundation excavations, observe proof roll and test compaction of subgrade and structural fill soils (as applicable) to confirm soils are as anticipated from the borings and foundations are prepared as recommended herein. The scope of work performed is specific to the proposed construction and the client identified by this report. Any other use of the data, recommendations and design parameters (as applicable) provided within this report are not appropriate applications. Other proposed construction and/or reliance by other clients will require project specific review by this firm. Changes in site conditions can occur with time. Changes in standard Rabbit Brush Compressor Station Garfield County, Colorado GEG Job No. 2,526 15 of practice also occur with time. This report should not be relied upon after a period of three years from the date of this report and is subject to review by this firm in light of new information which may periodically become known. We believe this investigation was conducted in a manner consistent with that level of care and skill ordinarily used by geotechnical engineers practicing in this area at this time. No other warranty, express or implied, is made. If we can be of further service in discussing the contents of this report or the analysis of the influence of the subsurface conditions on the development or design of the proposed construction, please call. Sincerely, GEOTECHNICAL ENGINEERING GROUP, INC. Reviewed by: Robert W. Anderson Norman W. Johnston, P.E. Project Geologist Senior Engineer RWA:NWJ:mh (3 copies sent) Rabbit Brush Compressor Station Garfield County, Colorado GEG Job No. 2,626 16 APPENDIX A SAMPLE SITE GRADING SPECIFICATIONS SAMPLE SITE GRADING SPECIFICATIONS Rabbit Brush Compressor Station Garfield County, Colorado Note: Appendix A presents sample specifications. These sample specifications are not project specific. The sample specifications should be modified by the Architect, Civil engineer or Structural engineer as needed to reflect project specific requirements.) 1. DESCRIPTION This item shall consist of the excavation, transportation, placement and compaction of materials from locations indicated on the plans, or staked by the Engineer, as necessary to achieve preliminary street and overlot elevations. These specifications shall also apply to compaction of excess cut materials that may be placed outside of the subdivision and/or filing boundaries. 2. GENERAL The Soils Engineer shall be the Owner's representative. The Soils Engineer shall approve fill materials, method of placement, moisture contents and percent compaction, and shall give written approval of the completed fill. 3. CLEARING JOB SITE The Contractor shall remove all trees, brush, and rubbish before excavation or fill placement is begun. The Contractor shall dispose of the cleared material to provide the Owner with a clean, neat appearing job site. Cleared material shall not be placed in areas to receive fill or where the material will support structures of any kind. 4. SCARIFYING AREA TO BE FILLED All topsoil and vegetable matter shall be removed from the ground surface upon which fill is to be placed. The surface shall then be plowed or scarified until the surface is free from ruts, hummocks or other uneven features, which would prevent uniform compaction by the equipment to be used. 5. COMPACTING AREA TO BE FILLED Job No. 2,526 Fig. A-1 After the foundation for the fill has been cleared and scarified, it shall be disked or bladed until it is free from large clods, brought to the proper moisture content (within 2 percent above or below optimum) and compacted to not less than 95 percent of maximum density as determined in accordance with ASTM D 698. If soft/ yielding subgrade conditions are encountered, stabilization may be required. 6. FILL MATERIALS Fill soils shall be free from vegetable matter or other deleterious substances, and shall not contain rocks or lumps having a diameter greater than six (6) inches. Fill materials shall be obtained from cut areas shown on the plans or staked in the field by the Engineer. On-site materials classifying as CL, SC, SM, SW, SP, GP, GC and GM are acceptable. Concrete, asphalt, organic matter and other deleterious materials or debris shall not be used as fill. 7. MOISTURE CONTENT Fill materials shall be moisture treated to within 2 ± percent of optimum moisture content as determined from Proctor compaction tests. Sufficient laboratory compaction tests shall be made to determine the optimum moisture content for thee various soils encountered in borrow areas. The Contractor may be required to add moisture to the excavation materials in the borrow area if, in the opinion of the Soils Engineer, it is not possible to obtain uniform moisture content by adding water on the fill surface. The Contractor may be required to rake or disk the fill soils to provide uniform moisture content through the soils. The application of water to embankment materials shall be made with any type of watering equipment approved by the Soils Engineer, which will give the desired results. Water jets from the spreader shall not be directed at the embankment with such force that fill materials are washed out. Should too much water be added to any part of the fill, such that the material is too wet to permit the desired compaction from being obtained, rolling and all work on that section of the fill shall be delayed until the material has been allowed to dry to the required moisture content. The Contractor will be permitted to rework wet material in an approved manner to hasten its drying. 8. COMPACTION OF FILL AREAS Job No. 2,526 Fig. A-2 Selected fill material shall be placed and mixed in evenly spread layers. After each fill layer has been placed, it shall be uniformly compacted to not less than the specified percentage of maximum density. Expansive soils classifying as CL or SC shall be compacted to at least 95 percent of the maximum dry density as determined in accordance with ASTM D 698 (100 percent for fill deeper than 15 feet below final grade). At the option of the Soils Engineer, soils classifying as SW, SP, GP, GC or GM may be compacted to 90 percent of the maximum density as determined in accordance with ASTM D 1557 (95 percent for fill deeper than 15 feet below final grade). Fill materials shall be placed such that the thickness of loose material does not exceed 10 inches and the compacted lift thickness does not exceed 6 inches Compaction, as specified above, shall be obtained by the use of sheepsfoot rollers, multiple -wheel pneumatic -tired rollers, or other equipment approved by the Engineer for soils classifying as CL or SC. Granular fill shall be compacted using vibratory equipment or other equipment approved by the Soils Engineer. Compaction shall be accomplished while the fill material is at the specified moisture content. Compaction of each layer shall be continuous over the entire area. Compaction equipment shall make sufficient trips to insure that the required density is obtained. 9. COMPACTION OF SLOPES Fill slopes shall be compacted by means of sheepsfoot rollers or other suitable equipment. Compaction operations shall be continued until slopes are stable, but not too dense for planting, and there is no appreciable amount of loose soil on the slopes. Compaction of slopes may be done progressively in increments of three to five feet (3' to 5') in height or after the fill is brought to its total height. Permanent fill slopes shall not exceed 3:1 (horizontal to vertical). 10. DENSITY TESTS Field density tests shall be made by the Soils Engineer at locations and depths of his choosing. Where sheepsfoot rollers are used, the soil may be disturbed to a depth of several inches. Density tests shall be taken in compacted material below the disturbed surface. When density tests indicate that the density or moisture content of any layer of fill or portion thereof is below that required, the particular layer or portion shall be reworked until the required density or moisture content has been achieved. 11. COMPLETED PRELIMINARY GRADES Job No. 2,526 Fig. A3 All areas, both cut and fill, shall be finished to a level surface and shall meet the following limits of construction: A. Overlot cut or fill areas shall be within plus or minus 2/10 of one foot. B. Street grading shall be within plus or minus 1/10 of one foot. The civil engineer, or duly authorized representative, shall check all cut and fill areas to observe that the work is in accordance with the above limits. 12. SUPERVISION AND CONSTRUCTION STAKING Observation by the Soils Engineer shall be continuous during the placement of fill and compaction operations so that he can declare that the fill was placed in general conformance with specifications. All inspections necessary to test the placement of fill and observe compaction operations will be at the expense of the Owner. All construction staking will be provided by the Civil Engineer or his duly authorized representative. Initial and final grading staking shall be at the expense of the owner. The replacement of grade stakes through construction shall be at the expense of the contractor. 13. SEASONAL LIMITS No fill material shall be placed, spread or rolled while it is frozen, thawing, or during unfavorable weather conditions. When work is interrupted by heavy precipitation, fill operations shall not be resumed until the Soils Engineer indicates that the moisture content and density of previously placed materials are as specified. 14. NOTICE REGARDING START OF GRADING The contractor shall submit notification to the Soils Engineer and Owner advising them of the start of grading operations at least three (3) days in advance of the starting date. Notification shall also be submitted at least 3 days in advance of any resumption dates when grading operations have been stopped for any reason other than adverse weather conditions. 15. REPORTING OF FIELD DENSITY TESTS Job No. 2,526 Fig. A4 Density tests made by the Soils Engineer, as specified under "Density Tests" above, shall be submitted progressively to the Owner. Dry density, moisture content, of each test taken and percentage compaction shall be reported for each test taken. 16. DECLARATION REGARDING COMPLETED FILL The Soils Engineer shall provide a written declaration stating that the site was filled with acceptable materials, or was placed in general accordance with the specifications. 17. DECLARATION REGARDING COMPLETED GRADE ELEVATIONS A registered Civil Engineer or licensed Land Surveyor shall provide a declaration stating that the site grading has been completed and resulting elevations are in general conformance with the accepted detailed development plan. Job No. 2,526 Fig. A.5 Geotechnical IOngineering Group, Inc. January 18, 2007 Revised January 19, 2007 Williams Production RMT Company Mr. Tom Fiore P.O. Box 370 Parachute, CO 81635 Subject: Geotechnical Investigation Rabbit Brush Compressor Station Garfield County, Colorado Job No. 2,526 Dear Mr. Fiore, As requested, a Geotechnical Engineering Group, Inc.. Re-evaluated the alternative for using a pier with skin friction design. As requested Geotechnical Engineering Group visited the above subject site on January 8, 2007 and drilled two additional borings to a total depth of 80 feet each. As requested by Ms. Judy Secary, P.E., Harris Group, Inc., Geotechnical Engineering Group has also provided additional design criteria for the subject site. PROPOSED CONSTRUCTION We understand proposed construction will consist of a petroleum compressor station. There will be various compressor pads weighing approximately 180 kips each, compressor building, pipe racks, related structures including skid mounted structures. There will be no below grade construction. If proposed construction changes or is different from what is stated, we should be contacted to review actual construction and our recommendations. Geotechnical, Environmental and Materials Testing Consultants Grand Junction - Montrose - Rifle - Crested Butte (970) 245-4078 • fax (970) 245-7115 • geotechnicalgroup.com 2308 Interstate Avenue, Grand Junction, Colorado 81505 Rabbit Brush Compressor Station GEG Job No. 2,526 Page 2 of 7 SUBSURFACE CONDITIONS Subsurface conditions at the site were investigated by drilling an additional two exploratory test borings. Subsurface conditions encountered in the two additional test borings consisted of sandy, silty clay with sparse gravel lenses to the maximum depth explored of 80 feet. No ground water was noted at the time of drilling. Skin Friction Drilled Pier Foundations 1. Friction Piers may be designed using a skin friction of 450 psf for pier surface area. Skin fiction should not be used for pier capacity for the upper portion of the pier to a depth of at least 3 pier diameters below the pier cap. 2. Piers should be minimum length of at least 35 feet. Specialty drilling equipment may be necessary to advance pier holes to minimum depth. We recommend a pier hole diameter of at least 30 inches. 3. Pier reinforcement and design should be provided by the structural engineer to resist tension in the event of swelling. Reinforcement should extend the full length of the piers and into grade beams and foundation walls. The structural engineer's design may require additional or alternative reinforcing and should be included in the foundation construction. 4. A minimum 6 -inch (or thicker) continuous void should be constructed beneath all grade beams and foundation walls, between piers, to concentrate dead load on the piers and to provide separation between the grade beams and/or foundation walls and the expansive site soils. 5. Foundation walls and grade beams should be well reinforced; the reinforcement should be designed by a qualified structural engineer. 6. Piers should be carefully cleaned prior to placement of concrete. Groundwater was not encountered at the time of this investigation to the depths investigated. Our experience indicates water may exist in the clay material. We believe problems associated with pier installation can be significantly reduced by using a "drill and pour" construction procedure; that is, placing concrete immediately after pier holes are drilled, cleaned and inspected. Pumping or tremie placement may be required for proper dewatering of the pier holes if water is encountered during drilling. Rabbit Brush Compressor Station GEG Job No. 2,526 Page 3 of 7 Concrete should not be placed in any pier hole containing more than 3 inches water. Due to recent experience with improper installation, we recommend the use of a contractor with previous drilled pier installation experience. 7. Formation of mushrooms or enlargements at the top of piers should be avoided during pier drilling and subsequent construction operations. It may be necessary to case the top portion of the pier holes with a sono tube type casing to a depth of flaring of the pier holes to prevent mushrooms or enlargements at the top of piers. 8. Installation of drilled piers should be observed by a representative of our firm to identify the proper bearing strata and confirm proper installation technique. Our representative should be called to visit the site at the time of the first pier excavation 9. Pier settlement will be less than ''A inch and differential movement will be less than' 'A inch. 10. Minimum pier spacing should be 3 pier diameters for full development of individual group capacity reduction. q =1+ a/90° (n-1) m + (m-1)/mn where m=number of rows, n=number of piles in a row, a=arc tan (d/s), s=spacing center to center of piles, d=pile diameter. 11. Drilled pier spring constant (vertical and lateral). Kv=22,000(d) and Kh=4.9(d) where d= pier diameter in inches FROST PROTECTION We understand the Garfield County Building Department recommends coverage of at least 36 inches at an elevation up to 8,000 feet and at least 42 inches for elevations above 8,000 feet for frost protection. Rabbit Brush Compressor Station GEG Job No. 2,526 Page of LATERAL EARTH PRESSURES Walls that are restrained not allowing movement and mobilization of the internal soil strengths such, as retaining walls, should be designed for at -rest lateral earth pressures. Walls that are allowed to deflect to mobilize internal soil strengths may be designed for active lateral earth pressures. Lateral earth pressure values are presented below and should be treated as equivalent fluid pressures. • At rest lateral earth pressure = 75 pcf • Active lateral earth pressure = 55 pcf • Passive lateral earth pressure = 250 pcf • Coefficient of friction between soil and concrete = 0.27 The site soils have tested swell potential with estimated swell pressures ranging from about 900 to 5,400 psf. If the site soils become wetted they may swell and may apply swell pressures to walls. The walls should be designed to resist the anticipated swell pressure. The influence of the swell pressure may be reduced by over excavating the site soils beyond the zone of lateral earth pressure and replacing with a non - expansive free draining granular material. The zone of lateral earth pressure may be determined as a 45 degree line drawn up from the outside bottom corner of the foundation. Water from surface runoff, precipitation or other surface or subsurface origins frequently flows through relatively permeable backfill placed adjacent to a structure and tends to saturate backfill materials. The lateral earth pressures presented above do not include hydrostatic pressures from saturated backfill. For these reasons the walls retaining soils should be provided with weep holes to allow drainage of backfill soils. The weep holes should be spaced about 4 to 6 feet on center, both horizontally and vertically. The lateral earth pressures are dependent upon the type of backfill materials. The above lateral earth pressures are for walls backfilled with compacted onsite soils. The structural engineer should provide structural reinforcing design for walls supporting lateral soil loads. Prior to wall backfill, walls should be structurally braced top and bottom to prevent deflection from lateral soil loads. Foundation walls should also be backfilled with a CDOT class 6 type road base. Rabbit Brush Compressor Station GEG Job No. 2,526 Page $of7 DYNAMIC SHEAR MODULUS The dynamic shear modulus presented in the report was base on laboratory test results. SEISMIC CONSIDERATIONS Based on our review of the 2003 IBC, the seismic design recommendations presented in our report dated December 15, 2006 are appropriate for this site. MAXIMUM SOIL BEARING CAPACITY The maximum soil bearing capacity for spread footings presented in the report is net soil bearing capacity. MODULUS OF SUBGRADE REACTION We calculated a modulus of subgrade reaction, Ks = 90 kcf LATERAL MODULUS OF SUBGRADE REACTION We calculated a lateral modulus of subgrade reaction, Ks = 60 kcf POISSONS RATIO We calculated a Poisson's ratio = .3 MODULUS OF ELASTICITY We calculated a modulus of elasticity, ES =100 ksf. SOIL DENSITY The average tested dry density is 111 pcf and the average moisture content is 4.9 percent. The average wet density is 116 pcf Rabbit Brush Compressor Station GEG Job No. 2,526 Page 6 of l BURIED PIPE We understand that an 8 to 12 inch diameter pipe will be buried approximately 5 feet below the ground surface. In our experience, generally a properly buried pipe will not have concentrated surface water runoff, such as from building roofs or paved areas, to provide a sufficient water source to mobilize soil volume changes. We suggest construction of the buried pipe include methods to help reduce the potential for a surface water source to infiltrate into the pipe trench backfill. The trench backfill should consist of a low permeability material, such as the onsite clay soils, which is moisture conditioned to within 2 percent of the optimum moisture content, placed in thin lifts and compacted to at least 95 percent of the standard Proctor maximum dry density. The surface of the site adjacent to buried pipes should be sloped away from the pipe area to promote rapid runoff of surface water away from the pipe area. LIMITATIONS All other recommendations presented in the geotechnical investigation report dated December 15, 2006, should be included in the design and construction of the residences. We believe that the information presented in this letter was prepared in a manner consistent with that level of care and skill ordinarily used by geotechnical engineers in this area at this time. No other warranty, expressed or implied, is made. If we may be of further service in discussing the contents of this letter or the geotechnical engineering aspects of your project please contact us. Sincerely, GEOTECHNICAL ENGINEERING GROUP, INC. Reviewed by: Robert W. Anderson Norman W. Johnston, P.E. Project Geologist Senior Engineer RWA:NWJ:cb (1 copy sent) 1 cc: Faxed to Tom Fiore Rabbit Brush Compressor Station GEG Job No. 2,526 Page 7 of 7 Williams Production RMT Company Rabbit Brush Compressor Station Garfield County, Colorado N J� Job No. 2,526-2 Vicinity Map Fig. 1 Note: This figure was prepared based on a map provided by Williams Production, RMT. •TH 1 TH-2 TH-3 • • Legend • Indicates location of exploratory test borings Rabbit Brush Job No. 2,526 Location of Exploratory Test Holes Fig. 2 Figure 4 PAGE 1 of 1 Fnginccring I i cchnica 1 Group, Inc. LOG OF TEST TEST BORING TH-1 PRLIENOJECT:T:Tom WilliamsFiore Gas Compressor Stations (Rabbit Brush) PROJECT NO.: 2526 C LOCATION: Rabbit Brush ELEVATION: DRILLER: Odell LOGGED BY: Greg DEPTH TO WATER> INITIAL: g AFTER 24 HOURS: -*.- DATE: 10/25/2006 DEPTH TO CAVING: L £ — e o Description 2 s- Ma o m 5." Y3 Notes 0 Clay, silty, slight sandy, very stiff, moist, brown, (CL) Organics noted to 1 foot depth j Bulk sample taken at 1 to 4 foot depth 41/12 Soil related chemicals such as salts noted Bulk 4 ^CTS CT 38/12 Soil related chemicals such as salts noted jCT 33/12 e j 12 3an2 Soil related chemicals such as salts noted CT 16 j 20 CT 31/12 Bottom of boring when terminated: 2011. 24 28 This Information pertains only to this boring and should not be interpreted as being indicitive of the site. Figure 4 PAGE 1 of 1 Geotechntca1 �k ngineering Croup, Ine. LOG OF TEST BORING TH-2 PROJECT: Williams Gas Compressor Stations (Rabbit Brush)2526 PROJECTNO.: CLIENT: Tom Fiore LOCATION: Rabbit Brush ELEVATION: DRILLER: Odell LOGGED BY: Greg DEPTH TO WATER> INITIAL: a AFTER 24 HOURS: : DATE: 10/25/2006 DEPTH TO CAVING: 1_ 4 oDescription d co F 43 m U Notes 0 Organics noted to 1 foot depth Soil related chemicals such as salts noted Soil related chemicals such as salts noted Soil related chemicals such as salts noted Soil related chemicals such as salts noted Soil related chemicals such as salts noted Clay, silty, sandy, medium stiff to very stiff, moist, brown, (CL) Bulk sample taken at 1 to 4 foot depth / 0 j32/12 Bulk CT 9/12 4 CT 14/12 e CT 22/12 CT 12 16 CT 25/12 20 Bottom of boring when terminated: 20 ft. 24 28 This information pertains only to this boring and should not be interpreted as being indicitive of the site. Figure 5 PAflF 1 of 1 Fiaure 6 PAGE 1 of 1 Inethniercal Egineg Gr4►np, i)[nAe. LOG OF TEST BORING TH-3 PROJECT: Williams Gas Compressor Stations (Rabbit Brush) PROJECT NO.: 2526 CLIENT: Tom Fiore LOCATION: RabbitBmsh ELEVATION: DRILLER: Odell LOGGED BY: Greg DEPTH TO WATER> INITIAL: g AFTER 24 HOURS: a DATE: 10/25/2006 DEPTH TO CAVING: IV 8 g Description = m ad E r CO 0= Notes 0 Organics noted to 1 foot depth Soil related chemicals such as salts noted Soil related chemicals such as salts noted Soil related chemicals such as salts noted Soil related chemicals such as salts noted Soil related chemicals such as salts noted Clay, silty, sandy, very stiti moist, brown, (CL) Bulk sample taken at 1 to 4 foot depth j �^ / j Bulk CTS 27/12 4 CT 20112 CT 22/12 9 12 CT 43/12 16 CT 50/11 20 Bottom of boring when terminated: 20 ft. 24 28 This information pertains only to this boring and should not be interpreted as being indicative of the site. Fiaure 6 PAGE 1 of 1 Fin11re 7 PAP,F 1 of 1 Geotechnical 11nuineering Grolup, Inc. LOG OF TEST TEST BORING TH-4 PROJECT: Williams Gas Compressor Stations (Rabbit Brush) PROJECT NO.: 2526 : TomFiore LOCATICLIENTON: RabbitBmsh ELEVATION: DRILLER: Odell LOGGED BY: Greg DEPTH TO WATER> INITIAL: -V AFTER 24 HOURS: 34 - DATE: 10/25/2006 DEPTH TO CAVING: £ $ «2 o Description Ic a a r s 03 U Notes 0 Organics noted to 1 foot depth Soil related chemicals such as salts noted Soil related chemicals such as salts noted Soil related chemicals such as salts noted Soil related chemicals such as salts noted Clay, silty, slight sandy, very stiff, moist, brown, (CL) Bulk sample taken at 1 to 4 foot depth 7 '1' ulk BCT7 22/ 2 a CT 22)12 CT 34/12 12 CT Sore 16 CT soe 20 DC DC 5/12 7 57/12 DC 57/12 DC 57/12 24 DC 46112 Bottom of boring when terminated: 25 ft. 2s This Information pertains only to this boring and should not be interpreted as being Indicative of the site. Fin11re 7 PAP,F 1 of 1 I eche ical Inc. 11ngfneer1ug Group, LOG OF TEST BORING TH-5 PROJECT: Williams Gas Compressor Stations (Rabbit Brush) PROJECT NO.: 2526 CLIENT: Tom LOCATION: Rabbit Brush ELEVATION: DRILLER: Odell LOGGED BY: Greg DEPTH TO WATER> INITIAL: -g AFTER 24 HOURS: : DATE: 10/25/2006 DEPTH TO CAVING: .C. Depth (feet) Description 0 n CD 0 R; Eotes co Blow Counts 0 Organics noted to 1 foot depth Soil related chemicals such as salts noted Soil related chemicals such as salts noted Clay, sandy, slight gravelly, stiff to very stiff, moist, brown, (CL) Bulk sample taken at 1 to 4 foot depth j j j Bulk CT 15/12 4 CT 2e/12 CT 17/12 e 12 CT 48/12 16 CT 50/10 20 Bottom of boring when terminated: 20 ft. 24 28 This information pertains only to this boring and should not be interpreted as being indicative of the site. rinmIrQ R P A r.N.r 1 of 1 Geotechnical ',ngineer1nM IGro«p, jnt LOG OF TEST BORING TH-6 PROJECT: Williams Gas Compressor Stations (Rabbit Brush) PROJECT NO.: 2526 CLIENT: Th LOCATION: Rabbit Brush ELEVATION: DRILLER: Odell LOGGED BY: Greg DEPTH TO WATER> INITIAL: - AFTER 24 HOURS: a DATE: 10/25/2006 DEPTH TO CAVING: L _ ^ ors Description U P. 0 m F 1n m o U Notes 0 Soil related chemicals such as salts noted Soil related chemicals such as salts noted Soil related chemicals such as salts noted Clay, sandy, silty, very stiff, moist, brown, (CL) Bulk sample taken at 1 to 4 foot depth 4 Sand, clayey, gravely, medium dense, moist, brown,(SP/GC) / X Bulk CT' CT 17/12 29112 4 Clay, sandy, slight silty, very stiff, moist, brown, (CL) a <7 ii , a CT 4W12 12 CT 32H2 Ct 50111 16 10-• Gravel, clayey, slight sandy, very dense, moist, brown, (GP/CL) 20 Bottom of boring when terminated: 20 ft. 24 28 This Information pertains only to this boring and should not be interpreted as being Indicative of the site. Figure 9 PAC -1F 1 of 1 Fin! ra 1n PAfP1nf1 Geotechnical Engineering Group, ape' LOG OF TEST BORING TH-7 PROJECT: Williams Gas Compressor Stations (Rabbit Brush) PROJECT NO.: 2526 ie LOCATION:CLIENT:Tom RabbitForBrush ELEVATION: DRILLER: Odell LOGGED BY: Greg DEPTH TO WATER> INITIAL: s AFTER 24 HOURS: T. DATE: 10/25/2006 DEPTH TO CAVING: £ rj Description U s 0 av E0 40 ~ 3 c 03 c3 Notes 0 Organics noted to 1 foot depth Soil related chemicals such as salts noted Soil related chemicals such as salts noted Soil related chemicals such as salts noted Soil related chemicals such as salts noted Clay, sandy, slight silty, slight gravelly, very stiff, moist, brown, (CL) Bulk sample taken at 1 to 4 foot depth j / jCT jCT j Bulk CTr 30/12 4 CT 50/12 30/12 a 12 32/12 16 CT 38112 20 Bottom of boring when terminated: 20 ft. 24 28 This information pertains only to this boring and should not be interpreted as being indicitive of the site. Fin! ra 1n PAfP1nf1 KEY TO SYMBOLS Symbol Description Strata symbols .••. SSM Notes: clay Poorly graded sand Poorly graded gravel These logs are subject to the interpretation by GEG of the soils encountered and limitations, conclusions, and recommendations in this report. 2. Results of tests conducted on samples recovered are reported in the report SWELL / CONSOLIDATION TEST REPORT 7 Percent Strain 0 nv G+ > N br • Percent Heave CD 1 WATER ADDED • — -1 2 — -2 3 100 200 500 1000 2000 5000 Applied Pressure psf Natural Dry Dens. (Pcf) LL PI Sp. Gr. Overburden (psf) Pc (psf) C c C r Swell Press. (psf) Heave % e 0 Sat. Moist. 6.1 % 116.7 865 3429 6.9 MATERIAL DESCRIPTION USCS AASHTO Project No. 2526 Client: Tom Fiore Project: Williams Gas Compressor Stations (Rabbit Brush) Source: TH-1 Elev./Depth: 2 Remarks: Fig. 11 Geoleeh nicul I' ngineeriupng Gro, Inc. SWELL / CONSOLIDATION TEST REPORT -2 —2 0 —1 —o WATER 1 ADDED Percent Strain 0 ro Percent Heave N M q 9 '9 " 100 200 500 1000 2000 Applied Pressure - psf Natural Dry Dens. (Pcf) LL PI Sp. Gr. Overburden (psf) Pc (psf) C° r (psf) % o Sat. Moist. 6.6 % 114.4 910 1513 2.5 MATERIAL DESCRIPTION USCS AASHTO Project No. 2526 Client: Tom Fiore Project: Williams Gas Compressor Stations (Rabbit Brush) Source: TH-2 Elev./Depth: 8 Remarks: Fig. 12 ngineerouping II,Gro/e ehnica1 Gr. Inc. SWELL / CONSOLIDATION TEST REPORT 0 1 —o — 2 3 — -2 WATER ADDED Ni...NN —3 Percent Strain > 0 0 v 0 0 a — -4 N g — x m _5 < m — -5 — -7 — -a — -9 '" 100 200 500 1000 2000 Applied Pressure - psf Natural Dry Dens. (Pc) LL PI Sp. Gr. Overburden (psf) Pc (psf) CcCr Swell Press. (Psfl Heave % e0 Sat. Moist. 4.3 % 93.7 1059 -2.7 MATERIAL DESCRIPTION USCS AASHTO Project No. 2526 Client: Tom Fiore Project: Williams Gas Compressor Stations (Rabbit Brush) Source: TH-3 Elev./Depth: 4 Remarks: Fig. 13 Geolethnital I I, ngineerouping Gr. Inc. SWELL / CONSOLIDATION TEST REPORT Dent Strain O n, L. 6 Percent Hf in V co N '- O hi WATER ADDED m 1 — -1 2 — 2 3 4 — 3 5 100 200 500 1000 2000 5000 Applied Pressure - psf Natural Dry Dens. (Pcf) LL PI Sp. Gr. Overburden (psf) PC (psf) C C C r Swell Press. (psf) Heave % e 0 Sat. Moist. 5.1 % 109.8 2038 5426 4.3 MATERIAL DESCRIPTION USCS AASHTO Project No. 2526 Client: Tom Fiore Project: Williams Gas Compressor Stations (Rabbit Brush) Source: TH-5 Elev./Depth: 6 Remarks: Fig. 14 Geotcrhnical I',ngineeruping Cro, Inc. SWELL / CONSOLIDATION TEST REPORT 2 2 -1 1 0 0 WATER ADDED Percent Strain o V O) (n A W N Percent Heave N ? o v q r 100 200 500 1000 2000 Applied Pressure - psf Natural Dry Dens. (pcf) LL PI Sp. Gr. Overburden (psf) Pc (psf) C c C r Swell Press. (psf) Heave o�0 e 0 Sat. Moist. 3.5 % 121.0 923 889 0.2 MATERIAL DESCRIPTION USCS AASHTO Project No. 2526 Client: Tom Fiore Project: Williams Gas Compressor Stations (Rabbit Brush) Source: TH-7 Elev./Depth: 6 Remarks: Fig. 15 Ge oter hn ie Yl I', nginerroup.ing GrInc. Vertical Deformation, in. Shear Stress, psi -0.015 -0.01 -0.005 www, 0 0.005 0.01 0015 0 9 7.5 6 4.5 3 1.5 35 7 10.5 Strain, % 14 x 0 0 5 10 15 Strain, % 20 1 3 2 Fail. Stress, psi 15 10 5 Results C, psi 1.36 4), deg Tan($) 21.7 0.40 .Fl 0 0 5 10 Normal Stress, psi 15 Sample No. 1 2 3 Water Content, % Dry Density, pcf 3 m Saturation, % 2 Void Ratio Diameter, in. Height, in. Water Content, % Dry Density, pcf Saturation, % Void Ratio Diameter, in. Height, in. Normal Stress, psi Fal . Stress, psi S rain, % Ult. Stress, psi Strain, % Strain rate, in./min. 1 w H 4.4 4.4 4.4 130.2 130.2 130.2 36.2 36.2 36.2 0.3429 0.3429 0.3429 1.94 1.94 1.94 1.00 1.00 1.00 19.3 19.3 19.3 130.2 130.2 130.2 157.3 157.3 157.3 0.3429 0.3429 0.3429 1.94 1.94 1.94 1.00 1.00 1.00 3.50 6.90 10.40 2.72 4.20 5.47 4.6 4.1 5.1 0.63 0.63 0.63 Sample Type: Description: Assumed Specific Gravity= 2.8 Remarks: Fig. 16 Client: Tom Fiore Project: Williams Gas Compressor Stations (Rabbit Brush) Source of Sample: TH-6 Depth: 8 Proj. No.: 2526 Date Sampled: rIeeleehniesil L Engineering Group, Int. Tested By: MH Checked By: TM C B 8 7 6 5 4 3 m N. 58+00 $ e7 NI W PFR9RNR. W GA�. I W R49 P' W W W PRIM BOUNDARY N mew 14!13 _ . p ieta 1 azolOW naa2 . 4. 1Y PROPOSED U' PARtlM I WTXEMRD PRNOIa I E OP 14-14 13 R - N. 66+00 (IE CORNE8 - N.E 112'34053.1RARAR) E 13310116' EL 55JB.48' PONT 5 ss a4 , Sd� SP '� N� ]3-0• NI0 � SBCITXIN WHSEE -CI-6405 RNCE N. 57+00 /$V0 y /r - ..• . � III N6+73 .� Iy I 23+73 — _. Ei.iu 7j N 66+00.+. II I pc II 0 I _ — �' w .T I� C — - -j , � � MIRE EYPANS FLANS NmE MOO N 6) II �.. N. 55+00LI]IIII 3'-0' PEBSMMEL (M1E - 1111 ■ NI I PERSONNEL GA1 Magi, IY1/ rT-0• . C 5400 N giggle I 11 %IS 818 ur:)��i1 p i5 z � 1.I I I I I I 1�I f� l lll l l l O ® 6WNN N. 63f— NI - 'r ■ LMR 3' SURFACING(SP)? USHO ROCK I Ii g 00 E SEE NOTE COIRENT ON WH-CFfi106X. SECTION 6x+13 - CCC BOL/.•E MCC BIDC_�N5� II 22+13 • � � I .�L �BlF A 1 IS 104 li WU ( COINER POINT N. 61+0 60100 N 13U33254. E I6264.16' EL 55134.75 E50+000OOROIHA1Es EL 124.76' - hlFE �—�BOMA4RTl' RA•EEGAIE- - — JI� II 1 ]'-0" PERSONNEL GATE -0'S 51/419 '.moi ---------- �' / . 49+0 Rpal,.PARC N 24'5606• W 700.04'- CWS ELAN WEBSTER HILL COMPRESSOR STATION VICINITY MAP LATITUDE: 3831' LONGITUDE: 10701'- QRAP10C SCATS EIN TER) imb-60 n NOTES:• 1. HORIZONTAL NA VEFIIC.U.. CONTROL 5 BASED at SURVEY DATA-FROAMEO BY D.R. GRIME AND ASSOCIATES. BASS - .' OF MONO FOR 0010 SYSTEM IS BASED 04 A UNE BETWEEN BENCH. NARIN B1 AND 132.: 2. PROPERTYUNEBOUNDARIES SOWN ARE FROM TRUE NORM. 3. ALL FOUNDATION ELEVATIONS ARE BUSED ON PAM'C000NATE SYSTEM WIIN ILP OF CONCRETE PGR'TNE COMPRESSOR BUILDING SIM SEI AT ELEVATION 100'-05. PANT COORDINATE ELEVALNNN 100'-0' IS LOCAL TO ACTUAL ELEVATION 5510'-0' BASED' N SURVEY DATA 4. 33' HIGH "PRA LIFE' SECOI00RY CONSISTENT STRUCTURE MRH LNG AND ACCESS SOIL AS NAMNFACMREO BY STOUR 013EL COMP/NY. SIRS FALLS- SO 0R APPROVED EQUAL A ALL MW iEML. TO BE 8-0' 0804 CNN 4M. 6. GRADING AND IOWNA90 SWLE BE ISMS FOR TUTUS BCNPREBSCR BUMPS EIPNSSN AA THE IME OF TWAT pPANBIOE THE ENURE BURNS SIZE 5 SAWN ON PLAN LS A HIDDEN UNE DRAWING ND. NH -CI -8402 WH -41-6403 NN -0-0404 EMIL-GNMNO A:.DW8NAGE PLAN-SHT 1 CML -GRADING A:'DRAINAGE PLAN -SHE 2 CML-GPAMNO & ERMOOE PAN -SNE 3 DATE Br MPU GATE BY WPO DESCRIPTION wens WILUAMS PRODUCTION RMT COMPANY 0 BB SSUED FOR CONSTRUCTION REV DATE BY APP'S PRELIMINARY ISSUE 1•.60•-0' w B CMTS AP10 OAPS) MCEDAY YR 12/ 3/ 1- NS a7 DATE '/47/07 Herds Group Ina: ENERGY - — CIVIL SITE PLAN WILLIAMS PROOUCTAN RAR CO. - WEENIER HILL PROJECT 61060. DRAWING NUMBER WH—CI-6401 REVD P. AC . .03511110 p - 15 , • bRNM l 1 (_ 14!13 _ . p ieta 1 azolOW naa2 . 4. 1Y PROPOSED U' PARtlM I WTXEMRD PRNOIa I E OP 14-14 13 ss a4 WEBSTER HILL COMPRESSOR STATION VICINITY MAP LATITUDE: 3831' LONGITUDE: 10701'- QRAP10C SCATS EIN TER) imb-60 n NOTES:• 1. HORIZONTAL NA VEFIIC.U.. CONTROL 5 BASED at SURVEY DATA-FROAMEO BY D.R. GRIME AND ASSOCIATES. BASS - .' OF MONO FOR 0010 SYSTEM IS BASED 04 A UNE BETWEEN BENCH. NARIN B1 AND 132.: 2. PROPERTYUNEBOUNDARIES SOWN ARE FROM TRUE NORM. 3. ALL FOUNDATION ELEVATIONS ARE BUSED ON PAM'C000NATE SYSTEM WIIN ILP OF CONCRETE PGR'TNE COMPRESSOR BUILDING SIM SEI AT ELEVATION 100'-05. PANT COORDINATE ELEVALNNN 100'-0' IS LOCAL TO ACTUAL ELEVATION 5510'-0' BASED' N SURVEY DATA 4. 33' HIGH "PRA LIFE' SECOI00RY CONSISTENT STRUCTURE MRH LNG AND ACCESS SOIL AS NAMNFACMREO BY STOUR 013EL COMP/NY. SIRS FALLS- SO 0R APPROVED EQUAL A ALL MW iEML. TO BE 8-0' 0804 CNN 4M. 6. GRADING AND IOWNA90 SWLE BE ISMS FOR TUTUS BCNPREBSCR BUMPS EIPNSSN AA THE IME OF TWAT pPANBIOE THE ENURE BURNS SIZE 5 SAWN ON PLAN LS A HIDDEN UNE DRAWING ND. NH -CI -8402 WH -41-6403 NN -0-0404 EMIL-GNMNO A:.DW8NAGE PLAN-SHT 1 CML -GRADING A:'DRAINAGE PLAN -SHE 2 CML-GPAMNO & ERMOOE PAN -SNE 3 DATE Br MPU GATE BY WPO DESCRIPTION wens WILUAMS PRODUCTION RMT COMPANY 0 BB SSUED FOR CONSTRUCTION REV DATE BY APP'S PRELIMINARY ISSUE 1•.60•-0' w B CMTS AP10 OAPS) MCEDAY YR 12/ 3/ 1- NS a7 DATE '/47/07 Herds Group Ina: ENERGY - — CIVIL SITE PLAN WILLIAMS PROOUCTAN RAR CO. - WEENIER HILL PROJECT 61060. DRAWING NUMBER WH—CI-6401 REVD P. D c 8 A B 5 5 4 3 2 1 terli i R W 7 W i W °� / ! 8 W 11_. .:eon_ W \�•� PC ClR9E ro W 18" CULVERT END REGROWS W(4/ 22LF n INCLUDING END SECTS) w \ : • /`, /\;. g W .- - 1�\ \ `\ 139.49' 144.19' / ---_--\i5M/ 112.00' -�— 76.23' A 900050° RT Pd�C 69.40' INV • 9000'00' LT ����% % PI CURVE XB X — X / X z 05.97' �.� WO9'OO RT 4240' % 11 t� % 7� % % si0 / / �.. \ } nv/ /1 6505'39' IS 212.00' 221.64' 233.46' 1 FENCE I / // ( `3540 \ II '1�' //SING`\ \PO CUROEro ... �... INV EL 5520.5 5521 .` \ \/\) �'� / / / / -1. aD - Ir -_ N. 58 / tl0/S�\ I \�5 • • 3// \\ \ \ \• \Stalk 'i�S // II > \\ •\IF . ... • ��� ...,_ ^ 1 __I J / / / / FENCE J ` — 111 1AII AI 'll \I I 1 N. 57+00 1 x I I I I I - �� ``\� • ` • '`�� • I &"' , 1 / 1 / I6/ �' / I il II 11 Il N.04 500---.I1 %•/ / --I-'- '---- f!!!!! \ ` _ -\ J�i_�---���__. x. \ ; • \ l •\ \ il;IET\\ x \ \ \ 1 x tic ----�_� '/, -� _mac_ __f'_ . —�='__C _yam CURVE DATA CWNEI 8. R T L - 1 51.00'00• RT 162.00' 139.49' 144.19' 2 39T03.00'18 112.00' 7437' 76.23' 3 900050° RT 4240 69.40' 85.97' 4 9000'00' LT 42.IXI' 59.40' 05.97' 5 WO9'OO RT 4240' 69.40' 85.97' 8 9000'00' RI 42,00' 59.40 85.93' 6505'39' IS 212.00' 221.64' 233.46' UN ELM GRAPHIC SCALE (W me mea. B9 x IFGEND NEW CONTOURS SWALE FLOALINE NOTES. 1. FINISH GRADE ELEVATIONS ANDCONTOURSARE TOP OF FINAL SURFACING. - 2 FINISH' ORAD€ SHALL SLOPE AWAY FROM .5,01AMG5 AT 5S FOR A MINIMUM OF 10.-0°. 3. ALL CUT OR RL SHALL NOT MEET 3H IV. 4, PROADE SILT FENCE N40 MAW BALE BARRIERS -M NECESSARY TO CONTROL EROSION DURING CONSTRUCTION 5. PROVIDE WRAP. AS NECES51RY. ATCULVERTEND' SECTIONS. CMN98. 10. 'AR-CF6301 %H -CI -5401 PENSIONS • CIVIL -SITE PUN ..._ CML -STRUCTURAL GENERAL NOTES DAIE BY AMID DFoCRPTION REV St APPY) ' DESCRIPTION IIIIam 1NWAMS..PRODUCTION RMT COMPANY 0 80 ISSUED FOR CONSTRUCTION REV DATE BY MP'D PRBMMALT ISSUE . SCALE DRAWN CHK'D APP'O JJ MO OAAY YR 12/13/00 L/IS/OA/ zhrial APP'0 Ae'd.tdi Harris Group Ina ENERGY CIVIL GRADING & DRAINAGE PLAN SHEET. 1 DATE • Xi%Ml VOLUME PR000CIION R WEBSIER N5.1- PROJECT ILL PROJECT 81060 DRAWING -NUMBER WH--CI-6402 REVL 0 B A 8 7 6 5 4 3 01337.0174 #1 N 5 E 2212.6 PC WRa£f1 PLAN GRAPEDC SCAB (Peon) 0 Inel - 10 ft NV EL 5521.5 12• CULVERT W/FIARE0 END SECTIONS (42 LF INCLUDING EIA SECTS) TITLE R WH -CI -8401 CM1t-SITE RAN er APP') REV nME ant DESGIdPI1ON WILUAMS PRODUCTION RMT COMPANY 0 a/IWR 60 SSIED FOR CONSTRUCTION - REV DATE 61' NYD PRELIM/NW ISSUE SCALE 04(0 APP0 1•-30-0• 1311 NOTES. 1. FOR NOTES, LEGEND AND CUFNE DATA SEE DRAWING WH -CI -6402. MO DAY TR 12/13/05 �. I(/do 1rby /PP'S Harris Group Inc. ENERGY CIVIL GRADING &. DRAINAGE .PLAN SHEET -2 0ANE • ;Fri° 'NRWMS RNIOVCI)N RMT 00. 115650 R HILL PROJECT 81080 DRAWING NUMBER WH—CI-6403 G W W W MATONLINE N. W 95+70 FON CONTINUATION SEE OW0. 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M1 -CI -8404 - _ Q5' RN EL 5520.5. 01337.0174 #1 N 5 E 2212.6 PC WRa£f1 PLAN GRAPEDC SCAB (Peon) 0 Inel - 10 ft NV EL 5521.5 12• CULVERT W/FIARE0 END SECTIONS (42 LF INCLUDING EIA SECTS) TITLE R WH -CI -8401 CM1t-SITE RAN er APP') REV nME ant DESGIdPI1ON WILUAMS PRODUCTION RMT COMPANY 0 a/IWR 60 SSIED FOR CONSTRUCTION - REV DATE 61' NYD PRELIM/NW ISSUE SCALE 04(0 APP0 1•-30-0• 1311 NOTES. 1. FOR NOTES, LEGEND AND CUFNE DATA SEE DRAWING WH -CI -6402. MO DAY TR 12/13/05 �. I(/do 1rby /PP'S Harris Group Inc. ENERGY CIVIL GRADING &. DRAINAGE .PLAN SHEET -2 0ANE • ;Fri° 'NRWMS RNIOVCI)N RMT 00. 115650 R HILL PROJECT 81080 DRAWING NUMBER WH—CI-6403 D C B A 8 7 B 4 3 2 MATCIMIE N. 51+00 FI ( lIIry1MTM1 Itt Vno. nn -m -vs 1 \ \ \ \ \-----7_ _ R 61+00 _ \\ I 1- \ I \ .. \\ N ( Rg1 h\ SM.-�. 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EDEGo Gyc .'\. —x—X Sr ,\`TP�9 /- �J —�� �____ 1� Gq\'TP9 �AC10ESS ROM 3 _--\ \\\T�J RIS �__Y \ \ / �/ E te81.3 \ j \` -------„C,1 �� i �s�''�� / s 1 1� I i l Saj_ I l i l l I / i i i �i�, I I sag i/ 4.4 �T, \✓ ._--- - `T� �s f N. 49+00 .n W W g CY W .1 GAS ..� / I �-0 GAS/- GPS 11 / ..52.1‘` XI W ,j L^�' W W \/ 44 � W 24:8 BEdN ACCESS ROAD 1it W In- - W PLAN GAANEC BCAIa (W FEET) 1 Lab ED IL ORMRIO 140. WI -C1 -&o1 CmL-SIZE Phil . DATE BY APP.0 .DESGRIPIIDN REV DATE BY DESCRIPRON Williams L✓ \MLUAMS PRODUCTION RMT COMPANY 0 BB JS ISSUED FOR CONSIRUOIION REV DATE BY PPP'D PRELEENNR ISSUE 1'.30-O CHK'D FRPO 11.111114-L NO DAY YR 12/13 0S 400 s7 a/.r/eq NOTES: 1. FORNOTES. LEGEND AND DRAWN° WH -C1-6402. DATA SFE Harris Group Inc. ENERGY APPROVED CIVIL GRADING & DRAINAGE PLAN -. SHEET 3 DATE. YALLIAMS PRO0001EIN RMT CO. 2,hY67 - WEBSTER HIM .. PROJECTDRAWING NUMBER 01060 WH—CI-6404. REV6, D c A 8 7 6 5 4 2 OR 'x214' D' WOOD STAKE SILT' FENCE DETAIL STRAW BLIES (EMBBEED6BALES ' STRAW BALE BARRIER DETAIL EROSION CONTROL DETAILS CONTMNMEAR LINER 'DURA LIFE SECONDARY ' CONTAINMENT STRUCTURE STNUCHIML FILL TYPICAL TANK CONTAINMENT SECTION ///---cane 9DEWAL - -COMPACTED SUBGRME TYP SIDEWALK CROSS SECTION L ? C)E ySE CONTROL JOINTS SIVL. BE A�iSVERS MORE G�OR19 !URINALS. RACED AT NCR MORE IRAN 50' INTERVALS. �IDPANSION � BESIDEWALKS AND 0 STOOPS; GS. ETC BACKFILL MYTH LOW PERMEABLE MATERNL COMPACTTO 955 MOD. PROCTOR DENSITY ArallW =pp AAA.* PI GRAVEL TYPICAL PIPE TRENCH DETAIL -2R SIOPE MIN PLANS ROAD B' COMPACT ROMAS BASE -SEES 25 REDO SLOPE LININ) PLANS Wainnaey 12" SCARIFIED & COMPACTED SUBGMOE TYPICAL ROAD SECTION 4tU1L6IILE FABRIC MAIM NO WI -a-6402 WEI-CI-6103 WH -CI -6404 DILE CML -GRINGO MID DR WAGE PUN -941 . CML -GRADING Mil- ONe46 E RAI -9T 2 CPA -GRADING AND DRAMAGE RAN -91T 3 BY IPP° DATE 1M APP'0 DESCRIPTION WTLUAMS PRODUCTION RMT COMPANY 0 BB ISSUED FOR CONSTRUCTION REV DATE ER MND • PRELIMINMIY ISSUE DRAWN CHK'D 62P'0 AS 110160 MO MY tl 13lia_ 01/29/01 �J. APND Pird, t RDOV ED Harris Group Inc. B/irJb, ENERGY 2br/v CIVIL GRADING AND DRAINAGE. MISCELLANEOUS DETAILS DATE 1/?/✓l PROJECT 61060 WILUAMS PRODUCIKKI RMT 00. WEBSTER HLL DRAWING NUMBiR WH—CI-6405 REV Geotechnical Engineering Group, Inc. GEOTECHNICAL INVESTIGATION Webster Hill Compressor Station Garfield County, Colorado Prepared For: Williams Production RMT Company P.O. Box 370 Parachute, CO 81635 Attention: Tom Fiore Job No. 2,526 December 15, 2006 Geotechnical, Environmental and Materials Testing Consultants Grand Junction - Montrose - Moab - Crested Butte (970) 245-4078 • fax (970) 245-7115 • geotechnicalgroup.com 2308 Interstate Avenue, Grand Junction, Colorado 81505 TABLE OF CONTENTS SCOPE 1 SUMMARY OF CONCLUSIONS 1 SITE CONDITIONS 2 PROPOSED CONSTRUCTION 2 SUBSURFACE CONDITIONS 3 SITE DEVELOPMENT 4 SEISMIC CONSIDERATIONS 5 FOUNDATIONS 5 DRILLED PIER FOUNDATIONS 6 SPREAD FOOTINGS- STRUCTURES SENSITIVE To MOVEMENT 8 SPREAD FOOTINGS- STRUCTURES WHERE MORE RISK OF MOVEMENT IS ACCEPTABLE 9 REINFORCED MAT FOUNDATIONS—WHERE MORE RISK OF MOVEMENT IS ACCEPTABLE 10 FLOOR SYSTEMS 11 BELOW -GRADE CONSTRUCTION 13 CONCRETE 13 SURFACE DRAINAGE 14 CONSTRUCTION MONITORING 15 LIMITATIONS 16 FIG. 1 - VICINITY MAP FIG. 2 - LOCATION OF EXPLORATORY BORINGS FIG. 3 - LEGEND AND NOTES OF EXPLORATORY BORINGS FIGS. 4 THROUGH 10 - LOGS OF EXPLORATORY BORINGS FIGS. 11 THROUGH 15 - SWELL CONSOLIDATION TEST RESULTS FIG. 16 - DIRECT SHEAR TEST RESULTS TABLE I - SUMMARY OF LABORATORY TEST RESULTS APPENDIX A - SAMPLE SITE GRADING SPECIFICATIONS SCOPE This report presents the results of our Geotechnical Investigation for the proposed Webster Hill, compressor station in Garfield County, Colorado. Our investigation was conducted to explore subsurface conditions and provide foundation design recommendations for the anticipated construction. The report includes descriptions of subsoil and groundwater conditions found in seven exploratory borings made during this investigation, recommended foundation systems, allowable design soil pressures and design and construction criteria for details influenced by the subsurface conditions. The report was prepared from data developed during field exploration, laboratory testing, engineering analysis and experience with similar conditions. A brief summary of our conclusions and recommendations follows. Detailed criteria are presented within the report. SUMMARY OF CONCLUSIONS 1. Subsoils found in the exploratory borings consisted of generally of 2 to 19 feet of sandy clay underlain by a formational claystone and sandstone material to the maximum depth explored of 19'/ to 20% feet. 2. Stiff to very stiff, sandy clay and very hard claystone materials were identified at foundation levels. We recommend drilled piers bedded in an underlying competent strata to reduce potential movement of structures. A competent stratum was identified at depths of 2 to 19 feet. A recommendation for shallow foundations supported by well -compacted engineered structural fill is also presented for structures where more risk of Webster Hill Compressor Station Garfield County, Colorado GEG Job No. 2,526 1 potential movement is acceptable. A discussion of alternatives, including detailed design and construction criteria are included in the text of the report 3. We believe slab -on -grade construction supported by the soil encountered will involve significant amount of movement. We recommend structurally supported floors in all finished areas. Detailed design and construction criteria area presented in the text of this report. 4. Surface drainage should be designed for rapid runoff of surface water away from the proposed structures. SITE CONDITIONS The subject site was located in Section 14, Township 6 South, Range 94 West in Garfield County, Colorado as shown on Fig.1. The subject site sloped north to south at an inclination of about 5 to 10 percent. Vacant BLM land was north, east, south and west of the site. PROPOSED CONSTRUCTION We understand proposed construction will consist of a petroleum compressor station. There will be various compressor pads, compressor building, pipe racks, related structures including skid mounted structures. There will be no below grade construction. If proposed construction changes or is different from what is stated, we should be contacted to review actual construction and our recommendations. Webster Hill Compressor Station Garfield County, Colorado GEG Job No. 2426 2 SUBSURFACE CONDITIONS Subsurface conditions at the site were investigated by drilling and sampling seven exploratory borings. Locations of the exploratory borings are shown on Fig. 2. Graphic logs of the soils found in the borings and field penetration resistance tests are presented on Figs. 4 through 10. Subsurface conditions encountered in the test borings included sandy clay from the ground surface to a depth of about 2 to 19 feet underlain by formational claystone and sandstone. The claystone in TH-3 is underlain by formational shale from a depth of about 14 feet to the maximum depth explored of 19'/ to 19'/ feet. The sandy clay was stiff to very stiff, moist, and brown to grey. The claystone was hard to very hard, moist and brown to grey. The sandstone was very hard, slightly moist to moist, and brown to grey. Nine sandy clay samples tested had moisture content ranging from 4.4 to 9.5 percent and eight of the samples had dry densities ranging from 92 to 128 pcf. Two sandy clay samples were tested for Atterberg Limits. The samples exhibited liquid limits of 26 and 30, and plasticity indexes of 10 and 15 and had 80 percent passing the No. 200 sieve (silt and clay sized particles). Five sandy clay samples were tested for swell consolidation characteristics using a one-dimensional oedometer apparatus. The samples exhibited 0.2 percent consolidation to 6.5 percent swell when wetted under a confining pressure of 250 to 500 psf with estimated swell pressures of 500 to greater Webster Hill Compressor Station Garfield County, Colorado GEG Job No. 2,526 3 than 2000 psf. One sandy, silty clay sample tested exhibited a cohesion of 200 psf and an internal angle of friction of 21 degrees. Two sandy, silty clay samples were tested for sulfates. The samples had 550 ppm water soluble sulfates. Results of laboratory testing are presented on Fig. 11 through 16 and summarized on Tables I. SITE DEVELOPMENT The surface should be scarified to a depth of 10 inches, moisture conditioned to 2 to 4 percent wet of optimum moisture content and compacted to at least 95 percent of standard Proctor (ASTM D 698) maximum dry density. On-site soils free of deleterious materials, organics and particles over 6 -inches diameter can be reused in non-structural areas during grading. Fill in structural areas may include special requirements as discussed later under the "FOUNDATIONS" section of this report. Additional fill placement should be moisture conditioned to 2 to 4 percent wet of optimum moisture content and compacted to at least 95 percent of standard Proctor (ASTM D698) maximum dry density in 10 -inch maximum thickness loose lifts. Subgrade soils and fill greater than 10 foot in depth should be moisture conditioned to 2 to 4 percent of optimum moisture and compacted to at least 100 percent maximum dry density standard Proctor (ASTM D698). Subgrade preparation, and placement and compaction of grading fill should be observed Webster Hill Compressor Station Garfield County, Colorado GEG Job No. 2,626 4 and tested by a representative of our firm during construction. Sample site grading specifications are included in Appendix A. SEISMIC CONSIDERATIONS Foundation and floor systems include structural support from the surficial sandy, silty clay soils. Based on 2000 UBC we believe the site is located in Seismic Zone 1. Based on our understanding of proposed construction and subsurface conditions, we suggest a "Site Class C" be used for foundation seismic design as described in 2000 IBC. Based on the field and laboratory results we suggest a shear modulus of 4 ksi. FOUNDATIONS This investigation indicates subsurface conditions at foundation levels generally consist of sandy clay and claystone formational material with significant swell potential. In our opinion, a foundation to better help mitigate risk of potential movement should be anchored below the zone of probable moisture variation and concentrate the weight of the structure to resist potential swell of the sandy, silty clay. In our opinion, a straight shaft drilled pier foundation or a driven pile foundation bedded in an underlying competent stratum most nearly satisfies these criteria. If the owner and builder accept Webster Hill Compressor Station Garfield County, Colorado GEG Job No. 2,526 6 the risk of significant foundation movement and associate damage the structures may be supported on spread footings or reinforced mat foundations. We present design and construction criteria for drilled pier foundations. We also provide spread footing and reinforced mat foundations for structures where significant movement is acceptable. These criteria were developed from analysis of field and laboratory data and our experience. The additional requirements (if any) of the structural engineer should also be considered. Drilled Pier Foundations 1. Piers should be designed for a maximum allowable end bearing pressure of 25,000 psf. The piers should be designed for end bearing only. Skin friction discussed below should be used only to resist uplift. 2. Piers should be designed for a minimum dead load pressure of 10,000 psf based on pier cross-sectional area. If this dead load cannot be achieved, pier length and bedrock penetration should be increased. The shale can be assigned a skin friction value of 1,750 psf for uplift resistance, at least 3 feet below the pier cap. 3. Piers should penetrate at least 10 feet into the formational claystone/sandstone strata and have a total length of at least 18 feet. Relatively hard drilling conditions are anticipated. Specialty drilling equipment may be necessary to advance pier holes in the formational material. We recommend a pier hole diameter of at least 12 inches. 4. Pier reinforcement should be designed by the structural engineer to resist tension in the event of swelling. Reinforcement should extend the full length of the piers and into grade beams and foundation walls. The structural Webster HDI Compressor Station Garfield County, Colorado GEG Job No. 2,526 6 engineer's design may require additional or alternative reinforcing and should be included in the foundation construction. 5. There should be at least a 6 -inch (or thicker) continuous void beneath all grade beams and foundation walls, between piers, to concentrate dead load on the piers. 6. Foundation walls and grade beams should be well reinforced; the reinforcement should be designed by a qualified structural engineer. 7. Piers should be carefully cleaned prior to placement of concrete. Groundwater was not encountered at the time of this investigation to the depths investigated. Our experience indicates permeable or fractured layers that may carry or store water may exist in the formational material. We believe problems associated with pier installation can be significantly reduced by using a "drill and pour" construction procedure; that is, placing concrete immediately after pier holes are drilled, cleaned and inspected. Pumping or tremie placement may be required for proper dewatering of the pier holes if water is encountered during drilling. Concrete should not be placed in any pier hole containing more than 3 inches water. Due to recent experience with improper installation, we recommend the use of a contractor with previous drilled pier installation experience. 8. Formation of mushrooms or enlargements at the top of piers should be avoided during pier drilling and subsequent construction operations. It may be necessary to case the top portion of the pier holes with a sono tube type casing to a depth of flaring of the pier holes to prevent mushrooms or enlargements at the top of piers. 9. Installation of drilled piers should be observed by a representative of our firm to identify the proper bearing strata and confirm proper installation technique. Our representative should be called to visit the site at the time of the first pier excavation. Webster Hill Compressor Station Garfield County, Colorado GEG Job No. 2,526 7 Spread Footings- Structures Sensitive To Movement 1. Bottom of footing should have a separation of at least 6 feet from the sandy clay. The clay samples tested had estimated swell pressures greater than 2,000 psf. If the clay becomes wetted it may swell with these pressures It if very difficult to provide adequate separation from material with swell pressures in this range to completely eliminate the influences of the swell pressures. The recommended 6 feet separation between the bottom of the footings and the top of the clay is intended to help reduce or mask the influence of soil volume changes. 2. Existing soils should be removed to at least a depth of 6 feet below and 6. feet horizontally beyond footings in each direction and replaced with a well - compacted engineered structural fill. The resulting subgrade should be prepared by scarifying 10 -inches, moisture conditioning to 2 to 4 percent wet of optimum moisture content and compacting to at least 95 percent of standard Proctor (ASTM D698) maximum dry density. Structural fill soils should consist of non -expansive well graded sands and gravels with a maximum particle size of 1% -inches, maximum 15 percent passing the No. 200 sieve and maximum liquid limit of 30. A CDOT type Class 5 aggregate base course would meet this criteria and is recommended. A sample of the proposed fill soils should be supplied to our office for acceptance testing, prior to use or import. Structural fill should be moisture conditioned to within 2 percent of optimum moisture content and compacted to at least 95 percent of standard Proctor (ASTM D698) maximum dry density in 10 -inch maximum loose lifts. 3. Footings bearing on well -compacted structural fill placed as stated above should be designed for a maximum soils bearing pressure of 2,500 psf. Footing should be designed with a minimum dead load as high as possible. Loose soils should be completely removed from foundation bearing areas, prior to placing concrete. 4. We recommend a minimum width of at least 18 -inches for continuous footings. Isolated pads should be at least 36 inches by 36 inches. Foundation walls should be well -reinforced top and bottom. We recommend reinforcement sufficient to span an unsupported distance of at least 15 feet. Reinforcement should be designed by the structural engineer. Webster Hill Compressor Station Garfield County, Colorado GEG Job No. 2,626 8 5. Based on a design soil bearing pressure of 2,500 psf, a footing width of about 18 inches and footings placed on a 6 feet thick layer of well compacted structural fill the estimated differential movement is about % to % inch. If wider footings are used we should be contacted to review the estimated settlement and provide additional recommendations where needed. 6. Exterior walls should be protected from freezing. Refer to local building code for details. 7. The completed foundation excavation should be observed by our representative for proof roll and to verify the foundation subgrade conditions are as anticipated from our exploratory borings. Geotechnical Engineering Group, Inc. should also be called to test compaction of subgrade and fill during placement. Spread Footings- Structures Where More Risk of Movement is Acceptable 1. The Bottom of footing should have a separation of at least 2 feet from the surface of the sandy, silty clay. The recommended 6 feet separation between the bottom of the footings and the top of the clay is intended to help mask soil volume changes. 2. Existing soils should be removed to at least a depth of 2 feet below and 2. feet horizontally beyond footings in each direction and replaced with a well - compacted structural fill. The resulting subgrade should be prepared by scarifying 10 -inches, moisture conditioning to 2 to 4 percent wet of optimum moisture content and compacting to at least 95 percent of standard Proctor (ASTM D698) maximum dry density. Structural fill soils should consist of well graded sands and gravels with a maximum particle size of 1' -inches, maximum 15 percent passing the No. 200 sieve and maximum liquid limit of 30. A CDOT type Class 5 aggregate base course would meet this criteria and is recommended. A sample of the proposed fill soils should be supplied to our office for acceptance testing, prior to use or import. Additional fill should be moisture conditioned to within 2 percent of optimum moisture content and compacted to at least 95 percent of standard Proctor (ASTM D698) maximum dry density in 10 -inch maximum loose lifts. Webster Hill Compressor Station Garfield County, Colorado GEG Job No. 2,525 9 3. Footings bearing on well -compacted structural fill placed as stated above should be designed for a maximum soils bearing pressure of 1,200 psf. Footing should be designed with a minimum dead load as high as possible. Loose soils should be completely removed from foundation bearing areas, prior to placing concrete. 4. We recommend a minimum width of at least 18 -inches for continuous footings. Isolated pads should be at least 36 inches by 36 inches. Foundation walls should be well -reinforced top and bottom. We recommend reinforcement sufficient to span an unsupported distance of at least 15 feet. Reinforcement should be designed by the structural engineer. 5. Based on a design soil bearing pressure of 1,200 psf, a footing width of about 18 inches and footings placed on a two feet thick layer of well compacted structural fill the estimated differential movement is about 2 to 4 inches. If wider footings are used we should be contacted to review the estimated settlement and provide additional recommendations where needed. 6. Exterior walls should be protected from freezing. Refer to local building code for details. 7. The completed foundation excavation should be observed by our representative for proof roll and to verify the subsurface foundation conditions are as anticipated from our exploratory borings. Geotechnical Engineering Group should also be called to test compaction of subgrade and fill during placement. Reinforced Mat Foundations —Where More Risk of Movement is Acceptable 1. Reinforced mat foundations can be designed for a maximum soil bearing pressure of 1,200 psf. When supported on a minimum 2 feet thick well compacted structural fill. Loose soils should be completely removed from foundation bearing areas, prior to placing structural fill or foundation concrete. Webster Hill Compressor Station Garfield County, Colorado GEG Job No. 2,528 10 2. Existing soils should be removed to at least a depth of 2 feet below and 2 feet horizontally beyond the mat in each direction and replaced with a well - compacted structural fill. The resulting subgrade should be prepared by scarifying 10 -inches, moisture conditioning to 2 to 4 percent wet of optimum moisture and compacting to at least 95 percent of standard Proctor (ASTM D698) maximum dry density. Structural fill soils should consist of well graded sands and gravels with a maximum particle size of 1'/2 -inches, maximum 15 percent passing the No. 200 sieve and maximum liquid limit of 30. A CDOT type Class 5 aggregate base course would meet this criteria and is recommended for structures where mitigating potential movement is a concern. A sample of the proposed fill soils should be supplied to our office for acceptance testing, prior to use or import. Structural fill should be moisture conditioned to within 2 percent of optimum moisture content and compacted to at least 95 percent of standard Proctor (ASTM D698) maximum dry density in 10 -inch maximum loose lifts. 3. Mat foundations should be well reinforced, both top and bottom. We recommend reinforcement sufficient to span an unsupported distance of at least 12 feet and to distribute load over the entire mat foundation. Reinforcement should be designed by the structural engineer. 4. Foundations should be protected from freezing. Refer to local building code for details. 5. The completed foundation excavation should be observed by our representative to verify subsurface foundation conditions are as anticipated from our borings and to test compaction. FLOOR SYSTEMS The near -surface soils which will support slab -on -grade floors exhibited significant movement potential. Some movement must be assumed. To our knowledge, the only reliable solution to control floor movement is the construction of floors supported by the foundation system over a minimum 12 inch void. In our opinion, drilled piers should be Webster Hill Compressor Station Garfield County, Colorado GEG Job No. 2,526 11 used in all foundation areas. If the owner and builder accept the risk of significant movement and associated damage, the floors may be constructed as slab on grade floors. The owner is cautioned that future maintenance of any slabs on grade may include the removal and replacement of the slabs. We recommend the following precautions for construction of slabs -on -grade at this site. These precautions will not prevent movement in the event the underlying conditions become wetted; they tend to reduce damage if movement occurs. 1. Slabs should be supported by at least a 2 foot depth of well compacted, structural fill as stated above under the "FOUNDATIONS, Spread Footings" section of this report. The completed subgrade should be scarified 10 -inches depth, moisture conditioned to within 2 percent of optimum moisture content and compacted to at least 95 percent of maximum standard Proctor (ASTM D698) dry density, prior to structural fill placement. A Geotechnical Engineering Group, Inc. representative should be called to visit the site to test compaction and observe soils in the excavation bottom and structural fill. 2. Slab -on -grade construction should be limited to unfinished areas and exterior flatwork where practical. 3. Slabs should be separated from exterior walls and interior bearing members with a slip joint which allows for free vertical movement of slabs. 4. The use of slab -bearing partitions should be minimized. Where such partitions are necessary, a slip joint allowing at least 6 inches of free vertical slab movement should be used. Doorways and stairwells should also be designed for this movement. 5. Underslab plumbing should be eliminated where feasible. Where such plumbing is unavoidable, it should be thoroughly pressure tested during Webster HIS Compressor Station Garfield County, Colorado GEG Job No. 2,526 12 construction for leaks and should be provided with flexible couplings. Plumbing extending through slab on grade floors should be separated from floor slab to allow independent movement. 6. Frequent control joints should be provided to reduce problems associated with shrinkage and curling. The American Concrete Institute (ACI) and Portland Cement Association (PCA) recommend a maximum panel size of 8 to 15 feet depending upon concrete thickness and slump, and the maximum aggregate size. We advocate additional control joints 3 feet off and parallel to grade beams and foundation walls. BELOW -GRADE CONSTRUCTION No below -grade construction is anticipated at this site. Typically, building foundation drains are not required for construction of this type. Crawl space, if any, in building areas should be sloped so that potential moisture will not collect in these areas, but flow out of the crawl space. Crawl space areas should also be well ventilated to reduce potential humidity and musty odors. CONCRETE Two samples (TH- 1 and TH-7 at 1-4 feet) were tested for water soluble sulfate concentrations. The test results indicate a water soluble sulfate concentration of 400 to 670 ppm. Concentrations in this area have been shown to have a moderate effect on Webster Hill Compressor Station Garfield County, Colorado GEG Job No. 2,526 13 concrete that comes into contact with the soils. American Concrete Institute (ACI) recommends a Type II (sulfate resistant) cement be used for concrete that comes into contact with the subsoils. In addition, concrete should have a maximum water -cement ratio of 0.50. SURFACE DRAINAGE Performance of foundations and concrete flatwork is influenced by surface moisture conditions. The site formational claystone has significant swell potential. The swell potential typically is mobilized by wetting. Reducing the potential for moisture migration into the site soil and formational claystone with reduce the risk of mobilization of swell potential of site materials. Risk of wetting foundation soils can be reduced by carefully planned and maintained surface drainage. Surface drainage should be designed to provide rapid runoff of surface water away from the proposed structures. We recommend the following precautions be observed during construction and maintained at all time after the construction is completed. 1. The ground surface surrounding the exterior of the structures should be sloped to drain away from the additions in all directions. We recommend a slope of at least 12 inches in the first 10 feet around the structures, where possible. In no case should the slope be less than 6 inches in the first 5 feet. The ground surface should be sloped so that water will not pond adjacent to the additions. Webster Hill Compressor Station Garfield County, Colorado GEG Job No. 2,526 14 2. Backfill around foundation walls should be moistened and compacted. 3. Roof downspouts and drains should discharge well beyond the limits of all backfill. Splash blocks and downspout extenders should be provided at all discharge points. 4. Landscaping, if any, should be carefully designed to minimize irrigation. Plants used close to foundations should be limited to those with low moisture requirements; irrigated grass should not be located within 5 feet of the foundation. Sprinklers should not discharge within 5 feet of foundations. Irrigation should be limited to the minimum amount sufficient to maintain vegetation; application of more water will increase likelihood of slab and foundation movements. 5. Impervious plastic membranes should not be used to cover the ground surface immediately surrounding the structures. These membranes tend to trap moisture and prevent normal evaporation from occurring. Geotextile fabrics can be used to limit the weed growth and allow for evaporation. CONSTRUCTION MONITORING Geotechnical Engineering Group, Inc. should be retained to provide general review of construction plans for compliance with our recommendations. Geotechnical Engineering Group, Inc. should be retained to provide construction -monitoring services during all earthwork and foundation construction phases of the work. This is to observe the construction with respect to the geotechnical recommendations, to enable design changes in the event that subsurface conditions differ from those anticipated prior to start of construction and to give the owner a greater degree of confidence that the additions are constructed in accordance with the geotechnical recommendations. Webster Hill Compressor Station Garfield County, Colorado GEG Job No. 2,626 15 LIMITATIONS The scope of services for this study does not include any environmental or biological (such as radon, mold, fungi, bacteria, etc.) assessment of the site or identification or prevention of pollutants or hazardous materials conditions. If the owner is concerned about the potential for such contamination or pollution, other studies should be performed. Seven exploratory borings were drilled in the proposed structure areas. The exploratory borings are representative of conditions encountered only at the exact boring locations. Variations in the subsoil conditions not indicated by the borings are always possible. Our representative should observe open foundation excavations, observe proof roll and test compaction of subgrade and structural fill soils (as applicable) to confirm soils are as anticipated from the borings and foundations are prepared as recommended herein. The scope of work performed is specific to the proposed construction and the client identified by this report. Any other use of the data, recommendations and design parameters (as applicable) provided within this report are not appropriate applications. Other proposed construction and/or reliance by other clients will require project specific review by this firm. Changes in site conditions can occur with time. Changes in standard Webster Hill Compressor Station Garfield County, Colorado GEG Job No. 2,626 16 of practice also occur with time. This report should not be relied upon after a period of three years from the date of this report and is subject to review by this firm in Tight of new information which may periodically become known. We believe this investigation was conducted in a manner consistent with that level of care and skill ordinarily used by geotechnical engineers practicing in this area at this time. No other warranty, express or implied, is made. If we can be of further service in discussing the contents of this report or the analysis of the influence of the subsurface conditions on the development or design of the proposed construction, please call. Sincerely, GEOTECHNICAL ENGINEERING GROUP, INC. Reviewed by: Robert W. Anderson Norman W. Johnston, P.E. Project Geologist Senior Engineer RWA:NWJ:mh (3 copies sent) Webster Hill Compressor Station Garfield County, Colorado GEG Job No. Z526 17 APPENDIX A SAMPLE SITE GRADING SPECIFICATIONS SAMPLE SITE GRADING SPECIFICATIONS Webster Hill Compressor Station Garfield County, Colorado Note: Appendix A presents sample specifications. These sample specifications are not project specific. The sample specifications should be modified by the Architect, Civil engineer or Structural engineer as needed to reflect project specific requirements.) 1. DESCRIPTION This item shall consist of the excavation, transportation, placement and compaction of materials from locations indicated on the plans, or staked by the Engineer, as necessary to achieve preliminary street and overlot elevations. These specifications shall also apply to compaction of excess cut materials that may be placed outside of the subdivision and/or filing boundaries. 2. GENERAL The Soils Engineer shall be the Owner's representative. The Soils Engineer shall approve fill materials, method of placement, moisture contents and percent compaction, and shall give written approval of the completed fill. 3. CLEARING JOB SITE The Contractor shall remove all trees, brush, and rubbish before excavation or fill placement is begun. The Contractor shall dispose of the cleared material to provide the Owner with a clean, neat appearing job site. Cleared material shall not be placed in areas to receive fill or where the material will support structures of any kind. 4. SCARIFYING AREA TO BE FILLED All topsoil and vegetable matter shall be removed from the ground surface upon which fill is to be placed. The surface shall then be plowed or scarified until the surface is free from ruts, hummocks or other uneven features, which would prevent uniform compaction by the equipment to be used. 5. COMPACTING AREA TO BE FILLED Job No. 2,526 Fig. Al After the foundation for the fill has been cleared and scarified, it shall be disked or bladed until it is free from large clods, brought to the proper moisture content (within 2 percent above or below optimum) and compacted to not less than 95 percent of maximum density as determined in accordance with ASTM D 698. If soft/ yielding subgrade conditions are encountered, stabilization may be required. 6. FILL MATERIALS Fill soils shall be free from vegetable matter or other deleterious substances, and shall not contain rocks or lumps having a diameter greater than six (6) inches. Fill materials shall be obtained from cut areas shown on the plans or staked in the field by the Engineer. On-site materials classifying as CL, SC, SM, SW, SP, GP, GC and GM are acceptable. Concrete, asphalt, organic matter and other deleterious materials or debris shall not be used as fill. 7. MOISTURE CONTENT Fill materials shall be moisture treated to within 2 ± percent of optimum moisture content as determined from Proctor compaction tests. Sufficient laboratory compaction tests shall be made to determine the optimum moisture content for thee various soils encountered in borrow areas. The Contractor may be required to add moisture to the excavation materials in the borrow area if, in the opinion of the Soils Engineer, it is not possible to obtain uniform moisture content by adding water on the fill surface. The Contractor may be required to rake or disk the fill soils to provide uniform moisture content through the soils. The application of water to embankment materials shall be made with any type of watering equipment approved by the Soils Engineer, which will give the desired results. Water jets from the spreader shall not be directed at the embankment with such force that fill materials are washed out. Should too much water be added to any part of the fill, such that the material is too wet to permit the desired compaction from being obtained, rolling and all work on that section of the fill shall be delayed until the material has been allowed to dry to the required moisture content. The Contractor will be permitted to rework wet material in an approved manner to hasten its drying. 8. COMPACTION OF FILL AREAS Job No. 2,526 Fig. A-2 Selected fill material shall be placed and mixed in evenly spread layers. After each fill layer has been placed, it shall be uniformly compacted to not less than the specified percentage of maximum density. Expansive soils classifying as CL or SC shall be compacted to at least 95 percent of the maximum dry density as determined in accordance with ASTM D 698 (100 percent for fill deeper than 15 feet below final grade). At the option of the Soils Engineer, soils classifying as SW, SP, GP, GC or GM may be compacted to 90 percent of the maximum density as determined in accordance with ASTM D 1557 (95 percent for fill deeper than 15 feet below final grade). Fill materials shall be placed such that the thickness of loose material does not exceed 10 inches and the compacted lift thickness does not exceed 6 inches Compaction, as specified above, shall be obtained by the use of sheepsfoot rollers, multiple -wheel pneumatic -tired rollers, or other equipment approved by the Engineer for soils classifying as CL or SC. Granular fill shall be compacted using vibratory equipment or other equipment approved by the Soils Engineer. Compaction shall be accomplished while the fill material is at the specified moisture content. Compaction of each layer shall be continuous over the entire area. Compaction equipment shall make sufficient trips to insure that the required density is obtained. 9. COMPACTION OF SLOPES Fill slopes shall be compacted by means of sheepsfoot rollers or other suitable equipment. Compaction operations shall be continued until slopes are stable, but not too dense for planting, and there is no appreciable amount of loose soil on the slopes. Compaction of slopes may be done progressively in increments of three to five feet (3' to 5') in height or after the fill is brought to its total height. Permanent fill slopes shall not exceed 3:1 (horizontal to vertical). 10. DENSITY TESTS Field density tests shall be made by the Soils Engineer at locations and depths of his choosing. Where sheepsfoot rollers are used, the soil may be disturbed to a depth of several inches. Density tests shall be taken in compacted material below the disturbed surface. When density tests indicate that the density or moisture content of any layer of fill or portion thereof is below that required, the particular layer or portion shall be reworked until the required density or moisture content has been achieved. 11. COMPLETED PRELIMINARY GRADES Job No. 2,526 Fig. A,3 All areas, both cut and fill, shall be finished to a level surface and shall meet the following limits of construction: A. Overlot cut or fill areas shall be within plus or minus 2/10 of one foot. B. Street grading shall be within plus or minus 1/10 of one foot. The civil engineer, or duly authorized representative, shall check all cut and fill areas to observe that the work is in accordance with the above limits. 12. SUPERVISION AND CONSTRUCTION STAKING Observation by the Soils Engineer shall be continuous during the placement of fill and compaction operations so that he can declare that the fill was placed in general conformance with specifications. All inspections necessary to test the placement of fill and observe compaction operations will be at the expense of the Owner. All construction staking will be provided by the Civil Engineer or his duly authorized representative. Initial and final grading staking shall be at the expense of the owner. The replacement of grade stakes through construction shall be at the expense of the contractor. 13. SEASONAL LIMITS No fill material shall be placed, spread or rolled while it is frozen, thawing, or during unfavorable weather conditions. When work is interrupted by heavy precipitation, fill operations shall not be resumed until the Soils Engineer indicates that the moisture content and density of previously placed materials are as specified. 14. NOTICE REGARDING START OF GRADING The contractor shall submit notification to the Soils Engineer and Owner advising them of the start of grading operations at least three (3) days in advance of the starting date. Notification shall also be submitted at least 3 days in advance of any resumption dates when grading operations have been stopped for any reason other than adverse weather conditions. 15. REPORTING OF FIELD DENSITY TESTS Job No. 2,526 Fig. A4 Density tests made by the Soils Engineer, as specified under "Density Tests" above, shall be submitted progressively to the Owner. Dry density, moisture content, of each test taken and percentage compaction shall be reported for each test taken. 16. DECLARATION REGARDING COMPLETED FILL The Soils Engineer shall provide a written declaration stating that the site was filled with acceptable materials, or was placed in general accordance with the specifications. 17. DECLARATION REGARDING COMPLETED GRADE ELEVATIONS A registered Civil Engineer or licensed Land Surveyor shall provide a declaration stating that the site grading has been completed and resulting elevations are in general conformance with the accepted detailed development plan. Job No. 2,526 Fig. A5 Williams Production RMT Company Webster Hill Compressor Station Garfield County, Colorado N Job No. 2,526-1 Vicinity Map Fig. 1 Note: This figure was prepared based on a map provided by Williams Production, RMT. Legend • Indicates location of exploratory test borings Webster Hill Job No. 2,526 Location of Exploratory Test Holes Fig. 2 I GeoLeehniea1 ngineeriug Group, Ine' LOG OF TEST BORING TH-1 PROJECT: Williams Gas Compressor Station (Webster Hill) PROJECT NO.: 2526-1 CLIENT: Tom Fiore LOCATION: Webster Hill ELEVATION: DRILLER: Odell LOGGED BY: Corey DEPTH TO WATER> INITIAL: s AFTER 24 HOURS: a DATE: 10/23/2006 DEPTH TO CAVING: 1_ L y w 15 o 2 Description 0 0 a (0 E r Co 0 = m0 Notes Organics noted to 6 foot depth Sample not recovered Sample not recovered Clay, sandy, very stiff, moist, brown/grey, (CL) Bulk sample taken at 1 to 4 foot depth /CT j / ZCT Bulk 33/12 2Bn2 CT CT 4anz e 12 aarz 1 C I son 16 199 Claystone, very hard, moist, brown, (CS) 20 Bottom of boring when terminated: 19.25. 24 28 This information pertains only to this boring and should not be interpreted as being Indlcitive of the site. Figure 4 PAGE 1 of 1 Figure 5 PAGE 1 of 1 Geotechnical 11ninecring Group, Inc. LOG OF TEST BORING TH-2 T: PRCWilliams Gas Compressor Station (Webster Hill) PROJECT NO.: 2526-1 CLIENT:OJE Tom Fiore LOCATION: Webster Hill ELEVATION: DRILLER: Odell LOGGED BY: Corey DEPTH TO WATER> INITIAL: -a AFTER 24 HOURS: : DATE: 10/23/2006 DEPTH TO CAVING: L. o Description IU 157 y rn F 3 m U Notes 0 Soil related chemicals such as salts noted Sample not recovered Clay, sandy, stiff to medium stiff, moist, brown, (CL) Bulk sample taken at 1 to 4 foot depth j j j j Bulk CT 23/12 4 CT 13/12 e CT 26/12 lz 14CT Sandstone, very hard, moist, brown, (SS) 50/4 CT 16 1 Bottom of boring when terminated: 19 ft. 19 -"-`may- 20 24 28 This information pertains only to this boring and should not be interpreted as being indicitive of the site. Figure 5 PAGE 1 of 1 Geotechnical engineering Groep, Inc. LOG OF TEST BORING TH-3 PROJECT:WilliamsFiore Gas Compressor Station (Webster Hill) PROJECT NO.: 2526-1 CLIETom NT: LOCATION: Webster Hill ELEVATION: DRILLER: Odell LOGGED BY: Corey DEPTH TO WATERS INITIAL: a AFTER 24 HOURS: DATE: 10/23/2006 DEPTH TO CAVING: 1_ t I�.. o w Description g a m 0 41 Z. 0, E r 0 o co00 Notes 0 45/12 Organics noted to 2 foot depth Sandstone tense noted at 4 1/2 to 5 1/2 foot depth Sandstone tense noted at 13 1/2 to 14 1/2 foot depth No sample recovered Clay, sandy, moist, grey, (CL) Bulk sample taken at 1 to 4 foot depth j j Bulk CT7 , Claystone, very hard, dry, grey, (CS) 4 CT soe CT so/s C f 47/4 e 12 14 Shale, very hard, dry, grey, (SH) 16 CT ss/.s 20 Bottom of boring when terminated: 19.25 ft. 24 28 This information pertains only to this boring and should not be interpreted as being indicitive of the site Figure 6 PAGE 1 of 1 jGeotechnical 11nsnecriug LOG OF TEST BORING TH-4 PROJECT: Williams Gas Compressor Station (Webster Hill) PROJECT NO.: 2526-1 CLIENT:LOCATION:Webster Hill ELEVATION: DRILLER: Odell LOGGED BY: Corey DEPTH TO WATER> INITIAL: * AFTER 24 HOURS: : DATE: 10/23/2006 DEPTH TO CAVING: _ y o w Description 2 E 41 TA to CO F w 3 E m 0 Notes 0 32/12 Organics noted to 4 foot depth Sample not recovered Sample not recovered Clay, sandy, stiff to very stiff, slightly moist, brown, (CL) Bulk sample taken at 1 to 4 foot depth j /^CTr / / j Bulk a CT 24/12 8 CT 31/12 12 Claystone, very hard, slightly moist, grey, (CS) t4 1 C f CT / 60/1 16 Ili 25/0 20 Bottom of boring when terminated: 19.25 ft. 24 28 Thi information pertains only to this boring and should not be Interpreted as being indicative of the site. Figure 7 PAGE 1 of 1 Geotechnical ',,n�ineerin� Group, 1[�Re. I LOG OF TEST BORING TH-5 PROJECT: Williams Gas Compressor Station (Webster Hill) PROJECT NO.: 25264 CLIENT: Tom Fiore LOCATION: Webster Hill ELEVATION: DRILLER: Odell LOGGED BY: Corey DEPTH TO WATER> INITIAL: -4 AFTER 24 HOURS: -� DATE: 10/23/2006 DEPTH TO CAVING: L i 11 11 o Description o . y a d rn 1- 3 c m U Notes 0 Soil related chemicals such as salts noted 5011 related chemicals such as salts noted Soil related chemicals such as salts noted Soil related chemicals such as salts noted Sample not recovered Clay, sandy,very stiff to medium stiff, slightly moist, brown, (CL) Bulk sample taken at 1 to 4 foot depth j / / Bulk CTr saris 4 CT 10/12 CT 16/12 e 12 CT sos CT 16 10 1 Claystone, very hard, slightly moist, brown, (CS) I1 zero 20 Bottom of boring when terminated: 19.25 ft. 24 28 This Information pertains onlv to this boring and should not be interpreted as being indicitive of the site. Figure 8 PAGE 1 of 1 .nineel'in� Ii,Geotechnical Groups Iue. LOG OF TEST BORING TH-6 PROJECT: Williams Gas Compressor Station (Webster Hill) PROJECT NO.: 2526-1 CLIENT: Tom Fiore LOCATION: Webster Hill ELEVATION: DRILLER: Odell LOGGED BY: Corey DEPTH TO WATER> INITIAL: * AFTER 24 HOURS: DATE: 10/23/2006 DEPTH TO CAVING: L w ai o� Description 0 Fl O co E >a, 0) co t. o mV Notes 0 Organics noted to 1 foot depth Clay, sandy, very stiff to stiff moist, brown, (CL) Bulk sample taken at 1 to 4 foot depth / /CT �j Bulkr soul Soil related chemicals such as salts noted 4 CT 28/12 Soil related chemicals such as salts noted Soil related chemicals such as salts noted 8 CT 23112 CT 48/12 12 14 Claystone, hard to very hard, moist, grey 16 20 CT 60,6 Bottom of boring when terminated: 19.5 ft. 24 28 This information pertains only to this boring and should not be interpreted as being indlcitive of the site. Figure 9 PAGE 1 of 1 Geotechnical I11ngInecr1ng ,GroupInr.. LOG OF TEST BORING TH-% WilliamsFioreWebster Gas Compressor Station (Webster Hill) PROJECT NO.: 2526-1 PRLOCCLIENOJETT: CTN:T: om AIOHill ELEVATION: DRILLER: Odell LOGGED BY: Corey DEPTH TO WATER> INITIAL: g AFTER 24 HOURS: : DATE: 10/23/2006 DEPTH TO CAVING: .L. d m Description 2 a 0 N E r m S = m 0 Notes 0 Organics noted to 6 foot depth Soil related chemicals such as salts noted Sample not recovered Clay, sandy, stiff to very stiff, slightly moist, brown, (CL) Bulk sample taken at 1 to 4 foot depth /®IrEll Bulk 30/12 ° =■ CT 12/12 12 e CT 12 14 Sandstone, very hard, slightly moist, grey, (SS) 16 25/0 20 Bottom of boring when terminated: 19.25 ft. 24 28 This information pertains only to this boring and should not be interpreted as being indicitive of the site. Figure 10 PAGE 1 of 1 Geotechnical IEngineering , Group, Inc. KEY TO SYMBOLS Symbol Description Strata symbols Notes: clay Claystone Sandstone Shale 1. These logs are subject to the interpretation by GEG of the soils encountered and limitations, conclusions, and recommendations in this report. 2. Results of tests conducted on samples recovered are reported in the report Figure 3 SWELL / CONSOLIDATION TEST REPORT Percent Strain O + N W A 6 • Percent Heave t0 in > 01 fV — O • 1 WATER ADDED 2 3 — -2 4 — -3 100 200 500 1000 2000 Applied Pressure - psf Natural Dry Dens. (Pcf) LL PI Sp. Gr. Overburden (psf) P (psf) CO Cr Swell Press. (psf) Heave % % Sat. Moist. 9.0 % 127.5 706 6.5 MATERIAL DESCRIPTION USCS AASHTO Project No. 2526-1 Client: Tom Fiore Project: Williams Gas Compressor Station (Webster Hill) Source: TH-1 Elev./Depth: 6 Remarks: Fig. 11 ngineering II,Ceoteehnieal Group, Inc. SWELL / CONSOLIDATION TEST REPORT -1 0 -1 —o WATER ADDED Percent Strain 0 CO -4 rn rn a w n Percent Heave N M 1 4 r m ' 100 200 500 1000 2000 Applied Pressure - psf Natural Dry Dens. (Pct) LL PI Sp. Gr. Overburden (psf) Pc (psf) C C C r Swell Press. (Pe) Heave % e o Sat. Moist. 5.0 % 104.3 710 0.5 MATERIAL DESCRIPTION USCS AASHTO Project No. 2526-1 Client: Project: Williams Gas Compressor Source: TH-2 Tom Fiore Station (Webster Hill) Elev./Depth: 2 Remarks: Fig. 12 Geo tech nieal Engineering I, Group, Inc. SWELL / CONSOLIDATION TEST REPORT 0 s —0 WATER ADDED • Percent Strain > N W J A 41 A W N Percent Heave 9 r 9 9 'u 100 200 500 1000 2000 Applied Pressure psf Natural Dry Dens. (Pcf) LL PI Sp. Gr. Overburden (psf) Pc (psf) C ° C r Swell Press. (psf) Heave % e o Sat. Moist. 4.4 % 95.3 949 544 MATERIAL DESCRIPTION USCS AASHTO Project No. 2526-1 Client: Tom Fiore Project: Williams Gas Compressor Station (Webster Hill) Source: TH-4 Elev.IDepth: 4 Remarks: Fig. 13 C co tern ni rol II EnCgiroup,neering Inr. SWELL / CONSOLIDATION TEST REPORT 0 0 -0 WATER ADDED --1 Percent Strain J 0 m V O) O) P tJ N Percent Heave N l7 q '9 fD h N N • • '" 100 200 500 1000 2000 Applied Pressure psf Natural Dry Dens. (pcf) LL PI Sp. Gr. Overburden (psf) Pc (psf) C° Cr Swell Press. (psf) Heave % e ° Sat. Moist. 5.6 % 95.5 954 -0.7 MATERIAL DESCRIPTION USCS AASHTO Project No. 2526-1 Client: Project: Williams Gas Compressor Source: TH-5 Tom Fiore Station (Webster Hill) Elev./Depth: 6 Remarks: Fig. 14 I Geoteehnical I Engironeerup,ing GInc. SWELL / CONSOLIDATION TEST REPORT 0 •• 0 1 WATER ADDED • Percent Strain CO m V O) U > W N Percent Heave N `? 4 '9 W N. - m rn • "' 100 200 500 1000 2000 Applied Pressure psf Natural Dry Dens. (Pcf) LL PI Sp. Gr. Overburden (psf) Pc (psf) C c Crr well Press. (psf) Heave % e 0 Sat. Moist. 6.8 % 103.0 958 -0.2 MATERIAL DESCRIPTION USCS AASHTO Project No. 2526-1 Client: Tom Fiore Project: Williams Gas Compressor Station (Webster Hill) Source: TH-7 Elev./Depth: 2 Remarks: Fig. 15 Gro technien1 ngineering 1,hGroup, Inc. Vertical Deformation, in. -0.015 -0.01 -0.005 Shear Stress, psi Dilation 0 conss 0.005 0.01 0 015 0 30 25 20 15 10 5 3 6 9 Strain, % 12 0 0 5 10 15 Strain, % 20 1 3 2 3 Fail. Stress, psi 15 10 5 Results C, psi 1.35 a, deg Tan ro 20.7 0.38 0 0 10 Normal Stress, psi 15 Sample No. Water Content, % Dry Density, pcf Saturation, % Void Ratio Diameter, in. Height in. Water Content, % Dry Density, pcf 2 Saturation, % Q Void Ratio Diameter, in. Height, in. Normal Stress, psi Fai . Stress, psi Strain, % Ult. Stress, psi Strain, % Strain rate, in./min. 1 1 2 3 6.3 6.3 6.3 102.6 102.6 102.6 27.1 27.1 27.1 0.6118 0.6118 0.6118 1.94 1.94 1.94 1.00 1.00 1.00 24.7 24.7 24.7 102.6 102.6 102.6 106.9 106.9 106.9 0.6118 0.6118 0.6118 1.94 1.94 1.94 1.00 1.00 1.00 3.50 6.90 10.40 2.61 4.08 5.21 1.5 2.1 1.5 0.63 0.63 0.63 Sample Type: Description: Clay, sandy, tan Specific Gravity= 2.65 Remarks: Fig. 16 Client: Tom Fiore Project: Williams Gas Compressor Station (Webster Hill) Source of Sample: TH-6 Depth: 4 Proj. No.: 2526-1 Date Sampled: Gealcehnieai I Engineering Grasp. Inc. Tested By: CC Checked By: TM PVCMI Land Planning Division 1038 County Road 323 Rifle, CO 81650 Ph. 970-625-5350 Fax 970-625-4522 Email: pvcm@hughes.net Project: Cottonwood Compressor Station to Webster Hill 24" Gathering Line. Submittal Item Tab 11- Sensitive Area Survey 9.07.04 (10) April 30, 2007 Mr. Fred Jarman Director Garfield County Building and Planning Department 108 8th Street, 4`h floor Glenwood Springs, CO 81601 Dear Mr. Jarman, Please find below relevant sections of the Garfield County Zoning Resolution in regards to the Cottonwood Compressor Station to Webster Hill 24" Gathering Line. 9.07.04 (10) "Sensitive Area Survey: List the types and areas of concern along the pipeline right-of-way, such as: sensitive plant populations, cultural, archeological, paleontological resources and wetlands identified during preconstruction environmental surveys, if applicable." 9.07.06 (3) a. notes "Pipeline operations shall be located in a manner to minimize their visual impact and disturbance of the land surface. a. The location of right-of-way shall be away from prominent natural features and identified environmental resources." 9.07.06 (5) "In no case shall an operator engage in activities which threaten an endangered species." Bargath, Inc. has contracted with a respected environmental science firm, West Water Engineering from Grand Junction, CO. Page 1 of 3 West Water Engineering has prepared a review and analysis of the proposed right-of-way alignment in regards to identification of sensitive and rare plant species and federally listed threatened and endangered birds. 1. There were no sensitive and rare plant species identified within the proposed pipeline right-of-way. 2. There were no federally listed threatened and endangered birds or nests identified within the proposed pipeline right-of-way. Bargath, Inc. will comply with all applicable state and federal laws during construction of the pipeline in regards to sensitive and rare plant species and federally listed threatened and endangered birds. Cultural, archeological, paleontological resources Please note that we have designed the new pipeline largely within existing disturbed right-of-way areas, thus, there would not be any cultural, archeological or paleontological resources within this proposed right-of-way. The attached WestWater Engineering survey bears this fact out. Wetlands Please see Tab 7- Regulatory Permit Requirements. Wetland disturbance is permitted by the U.S. Army Corp of Engineers via the Nationwide Permit 12 for utility activities noted. Issues Regarding Studies on Private Property An area of concern is the preparation of the materials noted above on private property. As noted in Tab 2 and previous areas within the application, the proposed Cottonwood Compressor Station to Webster Hill 24" gathering line is on private property for the Garfield County portion of the pipeline and on federal property for the portion being applied for with the U.S. BLM. We believe that the studies required by Garfield County regarding sensitive and rare plant species, federally listed threatened and endangered birds and cultural, archeological and paleontological resources on private property can, and will, cause issues with private property owners. The studies noted are typically required for activities that occur on public property such as the U.S. Bureau of Land Management. These studies are typically not welcome and are many times not allowed on private property. Page 2 of 3 Bargath, Inc. has been proactive in this pipeline process by contracting West Water Engineering to review these issues and to guide Bargath, Inc. in the planning and construction of the pipeline. We have included a copy of the West Water Engineering report to this permit application, but do so in protest. We will follow the recommendations of the study and want to be respectful to both our private property owners and to the Garfield County permitting process. Please contact me with any questions. Sincerely, r Philip B. aughan President PVCMI Page 3 of 3 Bargath Cottonwood Gulch to Webster Mesa 24 Inch Gathering Pipeline System Webster Hill and Rabbit Brush Compressor Stations Sensitive Area Survey Report Garfield County, CO Prepared for: Bargath, Inc. C/O Williams Production RMT Parachute, CO Prepared by: WestWater Engineering 2516 Foresight Circle, #1 Grand Junction, CO 81505-1022 970-241-7076 April 2007 Bargath Cottonwood Gulch to Webster Mesa 24 Inch Gathering Pipeline System Rabbit Brush and Webster Hill Compressor Stations Sensitive Area Survey Report Garfield County, CO April 2007 INTRODUCTION WestWater Engineering (biological surveys) in coordination with Grand River Institute (GRI) (cultural resources survey) conducted a sensitive area and biological survey alongand adjacent to the proposed pipeline alignment and compressor stations for Williams Production RMT (Bargath, Inc). The objectives of the survey were to document the following natural resource characteristic and features • Identify and map areas where sensitive and rare plant species occur, • Locate raptor (bird of prey) nest sites and identify potential raptor habitat and use areas, • Characterize and map habitats along the proposed pipeline alignment in regards to suitability for wildlife and in particular for Birds of Conservation Concern, • Identify and map areas of potential habitat for federally listed threatened and endangered wildlife species, • Identify sensitive mule deer habitat, • Identify potential aquatic resources (fisheries) in the project area, • Determine if any wetlands are present in the project area, • Identify the presence of any cultural, archeological or paleontological resources. All locations of survey observations were recorded using handheld Global Positioning System (GPS) units and locations were recorded as Universal Transverse Mercator (UTM) coordinates (Datum: NAD83, Zone: I3S). Locations of observed raptor nests and other sensitive areas are depicted on attached Figure 1. GENERAL PROJECT AND HABITAT DESCRIPTION The Bargath Cottonwood to Webster Mesa project consists of a proposed 24 inch natural gas gathering pipeline and related compressor facilities installed along a corridor of approximately 8.3 miles in length and is generally located north of I-70 west of Rifle, Colorado in the Lower Colorado River drainage (Figure 1). The proposed pipeline will connect with a 30 inch pipeline, which was constructed in 2006 and currently ends at the mouth of Cottonwood Gulch. The eastern portion of the pipeline will connect to a compressor facility on Webster Mesa (Webster Hill Compressor Station). Included as part of this project is a new compressor facility (Rabbit Brush Compressor Station) that will be constructed approximately 1.5 miles west of Cottonwood Gulch and will connect with the existing 30 inch pipeline. The proposed pipeline is within Garfield County, State of Colorado, and is located both on private and Bureau of Land Management (BLM) lands. Approximately 1.46 miles of the alignment are on BLM property. WestWater Engineering 2 of 14 April 2007 The proposed pipeline parallels existing natural gas pipeline(s) right-of-way on Webster Mesa and along a portion of east Sharrard Park. The remaining portion of the pipeline is proposed to be constructed along a new pipeline corridor alignment. Vegetation communities along the pipeline route are categorized as pinon juniper woodlands and mixed sagebrush and greasewood shrublands. No agricultural meadows are affected. Pinon- juniper woodlands are dominated by pifion pine (Pinus edulis) and Utah juniper (Juniperus utahensis) and can be mixed with an understory of mainly Wyoming sagebrush (Artemesia tridentata wyomingensis.), forbs and grasses. No riparian communities are directly affected by the project. Numerous ephemeral washes bisect the alignment, most often in a north to south flow pattern. Vegetation along the washes consists of greasewood (Sarcobatus vermiculatus), Rabbitbrush (Chrysothamnus nauosausis), basin sagebrush (Atermesia tridentata tridentata). The shrublands within the project area are composed of mainly Wyoming big sagebrush, greasewood, and rabbitbrush (Chrysothamnus viscidijforus). Non-native downy brome (Bromus tectorum) dominates the understory for this shrubland community. BIRDS OF CONSERVATION CONCERN; THREATENED AND ENDANGERED BIRD SPECIES; OTHER AVIAN SPECIES As part of the protection and management of avian species, the U.S. Fish and Wildlife Service (USFWS) in 2002 published a list of Bird Species of Conservation Concern (BOCC). In a Memorandum of Understanding (MOU), the BLM, USFWS and U.S. Forest Service placed the highest priority for conservation on birds included on the bird species of conservation concern list. A subset of this list includes aregister of Birds of Concern for the Southern Rockies and the Colorado Plateau, including western Colorado. Not all of these BOCC bird species occur regularly in Colorado, and some are present only as seasonal migrants. Of those known to breed in Colorado, only a portion are known or suspected to breed within the vicinity of the proposed pipeline. After a thorough review of the literature (Andrews and Righter 1992, Kingery 1998), WestWater biologists compiled a list of species likely to nest along or near the proposed pipeline. Habitat and nesting records for these Birds of Conservation Concern, as described in the Colorado Breeding Bird Atlas (Kingery 1998, and references therein) and Colorado Birds (Andrews and Righter 1992), in the vicinity of the pipeline are summarized below. Bird identification and taxonomic nomenclature are in accordance with that applied by the Colorado Breeding Bird Atlas Project (Kingery 1998). RAPTORS (Including those that are Birds of Conservation Concern, but excluding Threatened & Endangered Listed Species) Nine species of raptors appear on the Birds of Conservation Concern (BOCC) species list for the Southern Rockies and the Colorado Plateau. Three of the BOCC raptors, the Burrowing Owl, Ferruginous Hawk, and the Short -eared Owl, are not likely to occur in the project area and the Bald Eagle is listed as a federal threatened species. In addition to the BOCC list, 8 other species of raptors could potentially be found nesting in the pipeline project area (Table 1). WestWater Engineering 3 of 14 April 2007 Table 1. Raptor species that may be present in the project area '3V - L A6�,V +$ -�iiulj�l �.ka �b4a.. .•Y '. q . ...vy`.i'§,zrs.x.3. �c 9. P�` fes. Northern Harrier Circus cyaneus Y • Grassland, shrubland, agricultural areas, and marshes. Nests in areas with abundant cover (e.g., tall reeds, cattails, grasses) in grasslands and marshes. Also known to nest in high -elevation sagebrush. Cooper's Hawk Accipiter cooperii N • Cottonwood riparian to spruce/fir forests, including pifion/juniper woodlands. Nests most frequently in pines and aspen. Sharp -shinned Hawk Accipiter striatus N • High density young, or even -aged, stands of coniferous forest and deciduous forests of aspen or oak brush with small stands of conifers. Red-tailed Hawk Buteo jamaicensis N • Diverse habitats including grasslands, pifion-juniper woodlands and deciduous, coniferous and riparian forests. Nests in mature trees (especially cottonwood, aspen, and pines) and on cliffs and utility poles. Swainson's Hawk Buteo swainsoni Y • Typically, arid grassland, desert, agricultural areas, shrublands and riparian forests. Nests in trees in or near open areas. Ferruginous Hawk Buteo regalis Y • Ungrazed to lightly grazed grassland and shrubland with varied topography. Nests in isolated trees, rock outcrops, structures such as windmills and power poles, or on the ground (especially on hill tops). Golden Eagle Aquila chrysaetos Y • Grasslands, shrublands, agricultural areas, pifion- juniper woodlands, and ponderosa forests. Prefers nest sites on cliffs and sometimes in trees in rugged areas. American Kestrel Falco sparverius N • Coniferous and deciduous forests and open terrain with suitable perches. Nests in cavities in trees, cliffs and buildings. Peregrine Falcon Falco peregrinus Y • Pifion-juniper woodlands and coniferous and riparian forest near cliffs. Nests on ledges of high cliffs away from human disturbance. Prairie Falcon Falco mexicanus Y • Grasslands, shrublands, and alpine tundra. Nests on cliffs or bluffs in open areas. Great Horned Owl Bubo virginianus N • Occupies diverse habitats including riparian, deciduous and coniferous forests with adjacent open terrain for hunting. Northern Saw- whet Owl Aegolius acadicus N • Mountain and foothills forest and canyon country. Significant use of pirion-juniper woodland and Douglas -fir. Long-eared Owl Asio otus N • Occupies mixed shrublands. Nests and roost in sites in dense cottonwoods, willows, scrub oak, junipers and dense forest of mixed conifers and aspens. WestWater Engineering 4 of 14 April 2007 Survey Procedures WestWater biologists surveyed and inventoried the project area for raptors on March 20, 29, 30, April 2 and 17, 2007 by walking and using vehicles to search cliffs and vegetation, including shrubs and trees for nests. In addition to the staked project area, potentially suitable sites within 0.25 miles of the pipeline route were inspected for the presence of nests. In this portion of Colorado, the raptor nesting season is generally considered to occur between mid-February and mid-August. Typically, owls and eagles are the first raptors to begin the annual nesting cycle followed by members of the Genus Accipiter, Buteo, Circus and Falco. Usually, by mid-August all young birds have fledged and left the nest. Observations WestWater biologists observed no active rantor nest sites during the survey. Seven inactive potential raptor nest sites were observed. One nest site was determined to have been used by Golden Eagles in the past, the other sites were most likely occupied in the past by Red-tailed or Cooper's Hawks. One stick nest located on a sandstone bluff is being used by a pair of Ravens during the 2007 nesting season. WestWater biologists assigned nest sites to specific raptor species based on knowledge of raptor occurrence in this area, as well as design, location, materials, and configuration of nesting structures. Three species of raptors were observed (flying or perching) in the project area during the survey including a single Red-tailed Hawk, one Swainson's Hawk and a pair of Golden Eagles. The pair of Golden Eagles have consistently been observed in the Sharrard Park area, but have not been observed using the single known eagle nest. The Swainson's Hawk was observed on one occasion and was considered to have been a passing migrant. The Red-tailed Hawk was observed near the west end of the pipeline alignment, but no nest was found after a thorough search. Inactive raptor nest locations are reported as follows: Accipiters Cooper's Hawk: Two suspected, but currently inactive, Cooper's Hawk nest sites were recorded along the pipeline corridor. CORA-1 (13S 253686mE, 4378781mN): Inactive 2007, no new nesting materials observed in the area. Nest in a juniper tree. COHA-2 (13S 253984mE, 4378456mN): Inactive 2007. Older nest located in a tall juniper tree. Nesting materials and lack of droppings and prey remains indicate lack of use for at least several years. Buteos Red-tailed Hawk: Four suspected Red-tailed Hawk nests were recorded along the pipeline route (RTHA-1 through RTHA-4). None have been found active during the 2007 nesting season. WestWater Engineering 5 of 14 April 2007 RTHA-1 RTHA-2 RTHA-3 RTHA-4 Golden Eagle GOEA-1 (13S 254572mE, 4378647mN): Inactive 2007. Confirmed active during 2006 nesting season. The site was located in a large sandstone bluff in the project area. During a previous WWE survey in this area during 2006, new nesting material, whitewash (excrement) and a Red-tailed Hawk tail feather found beneath the nest site indicated that the nest was most likely occupied by a Red-tailed Hawk. The 2006 survey was conducted well past the time when young birds would have been expected to fledge. (13S 254070mE, 4378408mN): Inactive 2007. Possible Red-tailed Hawk stick nest in a sandstone bluff overlooking I-70. Occupied by a pair of Raven during the 2007 biological survey on 3/20/2007. (13S 251670mE, 4377693m1\1): Inactive 2007. Medium-sized stick nest in good condition in a rock outcrop above Sharrard Park south of the pipeline alignment. Probably not active during the 2006 nesting season. No recent droppings or prey remains below the nest structure. (13S 244584mE, 4375072mN): Inactive 2007. Older nest located in a sandstone bluff. It was difficult to determine its condition; no birds were present. (13S 251838mE, 4378345mN): Inactive 2007. Large nest located in a sandstone bluff on the east side of Sharrard Park. A pair of Golden Eagles have been observed in the area, but have not been observed at this nest site. Recommendations and Discussion for Raptors Activities associated with the proposed project have the potential to impact raptor populations. In order to reduce the potential for impacts, if any active nests are located, it will be important that the project proponent schedule construction activities such that they do not interfere with breeding, nesting and brood rearing activities. The Colorado Division of Wildlife (CDOW) recommended raptor nest site avoidance standards for the species observed in this survey are summarized below (Table 2). Table 2. Colorado Division of Wildlife raptor active nest avoidance standards. Reference: Recommended Buffer Zones and Seasonal Restrictions For Colorado Raptors, Gerald Craig, Colorado Division of Wildlife. 2005. BIRDS OF CONSERVATION CONCERN (other than raptors) Survey Procedures In addition to raptors presented above, WestWater biologists surveyed the proposed pipeline route for the presence of sensitive or migratory BOCC that could potentially occur in the project WestWater Engineering 6 of 14 April 2007 0 :F " L , l ., r 141 �. i r•,,yy^�k O b Red-tailed Hawk 0.33 mile February 15 to July 15 Golden Eagle 0.5 mile February 15 to July 15 Coopers Hawk No buffer recommended None Recommended Reference: Recommended Buffer Zones and Seasonal Restrictions For Colorado Raptors, Gerald Craig, Colorado Division of Wildlife. 2005. BIRDS OF CONSERVATION CONCERN (other than raptors) Survey Procedures In addition to raptors presented above, WestWater biologists surveyed the proposed pipeline route for the presence of sensitive or migratory BOCC that could potentially occur in the project WestWater Engineering 6 of 14 April 2007 area in order to help evaluate the potential impacts of this project. BOCC habitat and nesting records, as described in the Colorado Breeding Bird Atlas (Kingery 1998, and references therein) and Colorado Birds (Andrews and Righter 1992), in the vicinity of the pipeline are summarized in Table 3. Table 3. BLM sensitive & migratory bird species that may be present in the project area _'' • IIS ^'{ [j tl ' 8, ` 115 e s S}.tat L_'F" _..� ate.-2.4.�"i Pinion Jay Gymnorhinus cyanocephalus • Pinon-juniper woodlands. Nests in pirfons or junipers. • Confirmed breeder in Garfield Counties in the vicinity of the pipeline, including the Roan Plateau. Vir, Virginia's g Warbler Vermivore virginiae • Dense shrublands and scrub forests of Gambel oak, pinon- juniper, mountain mahogany or ponderosa pine. Nests on the ground among dead leaves or on rock or log overhangs. • Nesting has been confirmed in Garfield Counties, including the Roan Plateau. Unlikely nester in the project area. Black -throated Gray Warbler Dendroica nigrescens • Mature pinon-juniper woodlands. Nests on horizontal branches in pifion or juniper. • Nesting has been confirmed in Garfield Counties in the vicinity of the pipeline, including on the Roan Plateau. Sage Sparrow Amphispiza belli • Large contiguous areas of low -elevation big sagebrush or sagebrush/greasewood shrublands. Nests in sagebrush. • Breeding has been been confirmed in Garfield Counties west of Parachute. None in the pipeline area. Observations No BOCC species were observed during the survey. Due to the dates of the survey, some of the migratory species such as Black -throated Gray have not yet migrated back into the project area. The species most likely to nest in this project area include the Pinyon Jay and Black -throated Gray Warblers who prefer mature pinion juniper woodlands for nesting. The primary suitable habitat for nesting would be in the pinon juniper woodlands in the segment of the pipeline running through the BLM lands. Recommendations Impacts to migratory species which nest in sagebrush and pillion -juniper woodland, the major vegetative types along the pipeline, can be minimized if surface disturbing construction activities take place outside the nesting season. This project will result in the loss of potential nesting sites when trees and shrubs are removed during construction. However, these vegetation types, especially sagebrush and pinon juniper, are generally abundant in the Parachute to Rifle area and the loss due to this project will represent a small portion of the habitat suitable for these birds. In order to reduce potential impacts on nesting birds, brush clearing in dense stands of sagebrush, pinon juniper woodlands habitats should take place outside of the nesting seasons. Nesting season is generally considered between May 15 and July 31 in this area. June 1 to July 15 is the peak period when most incubation and brood rearing takes place. If brush clearing can WestWater Engineering 7 of 14 April 2007 occur prior to May 1, most affected birds will relocate to alternate nesting sites. After mid to late July, most fledging has occurred and brush clearing impacts would be minimized. Pinyon Jays are an exception to typical nesting periods in this area and are known as an early nester. Records show nests with eggs as early as March 23. Often young birds have fledged by mid-May each year. Construction occurring after May 31 will reduce the possibility of impacts to this species. Black -throated Gray Warblers almost always select mature prion juniper habitat for nesting and rarely select sites outside this habitat. Pifion-juniper woodlands within the project area are found mostly on the BLM lands. Minimizing the disturbance to existing mature piton juniper woodlands in these areas would reduce potential affects to this species. FEDERALLY LISTED THREATENED & ENDANGERED BIRDS The Bald Eagle, a federally listed Threatened bird species has the potential to occur in habitat associated with the project area (Table 4). Procedures WestWater biologists used reference reports to identify the likelihood this species could be impacted by the proposed project. The search focused on potential locations for nests, perches and potential habitat. Additionally, CDOW maps and information regarding Bald Eagle breeding and habitat use in the general area were consulted. Table 4. Federally -listed threatened, endangered & candidate bird species sv5.,zk ��s, 2. y =k3 �, h6 yy��.}II-nn -� Www -'• 1 if • Along the lower Colorado River corridor nests in cottonwood woodlands in the crowns of large trees. Not known to nest in upland areas north of I-70 in this area. According to the Colorado Division of Wildlife's Natural Diversity Information Source (NDIS; http://ndis.nrel.colostate.edu/index.html), Bald Eagle Bald Eagle Haliaeetus winter range, winter foraging areas, and winter leucocephalus concentration areas are along the Colorado River outside the project area and south of I-70. • Two known active nests are within 5 miles of the pipeline alignment. One historically active nest site is known to occur south of Sharrard Park in section 29 along the Colorado River (Figure 1). Observations No individuals or nests of this species were observed during this survey within 0.5 miles of the project area. However, one currently active nest was recently (4/17/2007 confirmed) found WestWater Engineering 8 of 14 April 2007 approximately 0.5 miles east of Webster Hill in section 27 along the south side of the Colorado River. This nest is approximately 1.5 miles south of the Sharrard Park/Webster Mesa portion of the pipeline alignment. The historic nest site in section 29 was surveyed and no Bald Eagle nesting was found; Great Blue Herons are currently (4/2007) occupying and nesting in the historic Bald Eagle nest tree. The project area contains no suitable Bald Eagle nesting sites and no nesting records were found along the pipeline alignment. The lower Colorado River riparian corridor provides suitable winter habitat for Bald Eagles. Suitable winter roosting habitat is typically cottonwood trees, which are presently dominated by mature trees. Roosting habitat tends to concentrated in cottonwood galleries and often in single, more isolated trees, which are found in the flood plain adjacent to the river. Due to the relatively moderate slope throughout the Colorado River Valley, the river has developed a meandering configuration, which has created oxbows, sloughs and braided channels. The predominance of old age class, mature trees has created suitable roosting habitat for Bald Eagles. It is likely that wintering Bald Eagles forage extensively in the pipeline project area. Bald Eagle often feed on the carcasses of mule deer which have died due to winter stress or highway road - kills. Recommendations There are no known active nests or roost sites in the project area and use is typically limited to winter months (December 1- March 15) outside the project area when numbers increase due to migrant concentrations. It is unlikely that the proposed project will affect Bald Eagles and it is not likely that special stipulations are required. If occupied habitats are identified during construction, activities should be scheduled such that they do not interfere with breeding, nesting, brood rearing, roosting and foraging activities. SPECIAL STATUS SPECIES PLANT SURVEY Available literature and publications prepared by the Bureau of Land Management, Grand Junction Field Office and Glenwood Springs Field Office (GSFO) were reviewed for a listing of rare plant species known to occur within the project area. In addition, the following information sources were reviewed for the most up to date status on the plant species that could possibly be expected within the inventory area. Species from these lists were included on the list of species sought during the field inventory. • Threatened or endangered species protected under the Federal Endangered Species Act and those which are candidates or proposed for listing (USFWS website: https://ecos.fws.gov/tens_public/servlet/gov.doi.tesspublic.servlets.EntryPage). • Species listed by the BLM as Sensitive in northwest Colorado (BLM website: http://www.co.blm.gov/botany/sens species.htm). • Species included on lists prepared by the Colorado Natural Heritage Inventory (website: http://www.cnhp.colostate.edu/list.html) for Garfield County, Colorado. WestWater Engineering 9 of 14 April 2007 Special status species (SSS) of plants that may be present in the project area, and their habitats, are listed below in three categories: 1) federally -listed Threatened or Endangered (1 species, Table 5), 2) Federal Candidate Species (2 species, Table 5), and 3) BLM Sensitive Species (4 species, Table 6). Nomenclature and habitat descriptions are based on the Colorado Natural Heritage Program (CHNP) literature (Spackman et al. 1997, Spackman and Anderson 2002, and references therein). Table 5. Federally -listed Threatened, Endangered and Candidate plant species fitS+S a e .b .. .nq vl t� dib ft.?,. �£�`rTS' , Penstemon debilis Parachute penstemon C Endemic to Garfield County with only five known occurrences; sparsely vegetated, south facing, steep, white shale talus in the Mahogany Zone of the Parachute Creek Member of the Green River Formation. Elev. 7,800-9,000 ft. Phacelia submutica DeBeque phacelia C Chocolate -brown or Gray clay on Atwell Gulch and Shire members of the Wasatch Formation; sparsely vegetated steep slopes. Elev. 4,700-6,200 ft. Sclerocactus glaucus Uinta basin hookless cactus T Typically xeric and fine textured Quaternary and Tertiary alluvium soils overlain with cobbles and pebbles; cold desert shrub and pifion-juniper communities along river benches, valley slopes, and rolling hills. * E= Federal Endange ed, T= Federal Threatened, C= Federal Candidate Table 6. BLM sensitive plant species •Ve ¢ ^1&v�stxN9�t"€-._$ a e .b .. .nq qtr&� a aa�' .�"fi,' p'iZ �rTr' :F.a:. Y°+. Vic= 9 SGY ..3'..',ni..-.3 ✓" z. -"- -tea`. Astragalus debequaeus Debeque milkvetch Varicolored, fine textured, seleniferous, saline soils of the Wasatch formation -Atwell Gulch member. Elev. 5,100-6,400 ft. Astragalus naturitensis Naturita milkvetch Sandstone mesas, ledges, crevices and slopes in pinion -juniper woodlands. Elev. 5,000-7,000 ft. Cirsium perplexans Adobe thistle Barren clay outcrops derived from shales of the Mancos or Wasatch formations; open and disturbed sites in mixed shrubland and pinon-juniper woodland. Elev. 5,000-8,000 ft. Menzelia rhizomata Roan Cliffs blazingstar Steep eroding talus slopes of shale, Green River formation. Elev. 5,800-9,000 ft. Procedures WestWater biologists surveyed and inventoried the project area for Threatened, Endangered and Sensitive plants in conjunction with other surveys by walking the proposed staked pipeline alignment and visually surveying areas of suitable habitat and plant communities. In addition, the area within 50 feet of the staked pipeline alignment was surveyed. The survey was conducted at a period when phenological development of most plant species was in the early flowering and/or emergent stage. Observations and Recommendations No T & E or sensitive plant species (TESS) were observed during the biological survey. The WestWater Engineering 10 of 14 April 2007 section of the pipeline alignment through BLM lands has terrain and soils that could potentially support TESS vegetation. This area was thoroughly surveyed and no plants were found. The closest known sites supporting the Debeque milkvetch are found in the northern portion of Sharrard Park and north of Webster Mesa. No known Debeque milkvetch populations will be affected by the proposed pipeline alignment or compressor stations. AQUATIC RESOURCES AND WETLANDS Procedures WestWater biologists surveyed and recorded information relating to aquatic resources and wetlands in conjunction with other surveys that were conducted for this report. Observations No Corps of Engineers jurisdictional wetlands were observed along the pipeline alignment. Vegetation along intermittent and ephemeral drainages was typically composed of sagebrush, greasewood, and snakeweed. Most often, these washes did not support any vegetation in the flow channels. Ephemeral drainages are likely to be considered Waters of the U.S. by the U.S. Army Corps of Engineers. MULE DEER Procedures WestWater biologists surveyed and recorded information relating to mule deer use in the area in conjunction with other surveys that were conducted for this report. Observations The native plant community along the majority of the pipeline alignment is dominated by Wyoming sagebrush and greasewood. The sagebrush community is this area is under stress due to multiple natural and man-made factors and the habitat in Sharrard Park is a good example of a poorly functioning native plant community. Segments of the Wyoming sagebrush in the I-70 corridor has been dying in the last few years and likely has been affected by recent drought conditions. During the weed survey for this project, dead and dying mature sagebrush was commonly observed throughout Sharrard Park. This result in a plant community that is dominated by a single age class of mature plants where there is little seedling replacement due to competition with downy brome. Natural gas development in Webster Mesa and Sharrard Park has further contributed to unnatural disturbance, which has affected native vegetation communities. These areas are important winter range for mule deer that migrate to the south from the Roan Plateau. Furthermore, the area supports limited mule deer populations during the summer. The Wyoming sagebrush community provides the basic winter forage (browse) for mule deer that depend on this habitat. The maintenance and enhancement of sagebrush has a high potential for the preservation of mule WestWater Engineering 11 of 14 April 2007 deer in this area. Recommendations Natural gas reclamation practices in disturbed areas in Sharrard Park show promise of reducing downy brome infestations following re -vegetation with shrub and grass species currently being used by the natural gas industry. Restoration of the plant communities in this area can be affected by reintroduction of native plant species. On BLM lands, in low elevations habitat similar to that encountered along the pipeline alignment, the Glenwood Springs BLM Energy Office has recently updated revegetation requirements for reclamation of natural gas disturbance and issued recommended seed mixes suitable for the potential natural community (BLM 2007). On private lands, Williams has developed a seed mix for reclamation that is suitable and acceptable to private landowners along the pipeline alignment. Both recommended seed mixes for BLM and private lands are presented in the Integrated Vegetation and Noxious Week Management Plan that WestWater prepared for Garfield County for this pipeline project (WestWater Engineering 2007). WestWater does not recommend the addition of non-native grasses in reclamation seed mixes such as crested wheatgrass and smooth brome, which can out -compete and replace native plant communities. CULTURAL RESOURCES WestWater has conferred with Grand River Institute (GRI) regarding potential cultural resources that may be found along the proposed alignment. GRI consulted with the Colorado State Historical Society in order to identify potentially sensitive areas located along the proposed Cottonwood pipeline. Three historic sites and one prehistoric site in the general vicinity of the alignment were listed as significant including the 5GF.654.2 Havermeyer-Wilcox Canal, 5GF.2310 High Line Canal, 5GF.2311 Low Line Canal, and 5GF.2330 Prehistoric Open Camp. GRI also contacted the BLM GSFO archaeologist. The BLM specialist indicated that the Havermeyer-Wilcox Pumphouse and Forebay have been delisted from the National Register of Historic Places. Apparently the canals that had been previously evaluated as eligible also now lack integrity of location and association and can be reevaluated as part of the ongoing study as not eligible. A verbal report from GRI indicates that no sensitive cultural, historic or prehistoric sites will be affected by the project. A written report of findings of the ongoing cultural resource surveys will be submitted to the BLM Glenwood Springs Field Office. REFERENCES Andrews, R. and R. Righter. 1992. Colorado Birds: A Reference to Their Distribution and Habitat. Denver Museum of Natural History, Denver. WestWater Engineering 12 of 14 April 2007 Bureau of Land Management. 2007. Revisions to BLM energy office revegetation requirements. Bureau of Land Management, Glenwood Springs, CO. Kingery, H.E. (Editor). 1998. Colorado Breeding Bird Atlas. Colorado Bird Atlas Partnership and Colorado Division of Wildlife, Denver. Natural Diversity Information Source (NDIS). 2005. Colorado Division of Wildlife. 6060 Broadway, Denver, CO. http://ndis.nrel.colostate.edu/index.html Spackman, S., B. Jennings, J. Coles, C. Dawson, M. Minton, A. Kratz, and C. Spurrier. 1997. Colorado Rare Plant Field Guide. Prepared for the Bureau of Land Management, the U.S. Forest Service and the U.S. Fish and Wildlife Service by the Colorado Natural Heritage Program. U.S. Fish and Wildlife Service. 2002. Birds of conservation concern 2002. Division of Migratory Bird Management. Arlington, VA. WestWater Engineering. 2007. Integrated vegetation and noxious weed management plan. Prepared for Bargath, Inc. as requested by Garfield County, CO. WestWater Engineering 13 of 14 April 2007 PVCMI Land Planning Division 1038 County Road 323 Rifle, CO 81650 Ph. 970-625-5350 Fax 970-625-4522 Email: pvcm@hughes.net Project: Cottonwood Compressor Station to Webster Hill 24" Gathering Line. Submittal Item Tab 13- Rehabilitation Plan. Includes Revegetation Plan 9.07.04 (12) and Weed Management Plan 9.07.04 (13). Steve Anthony- Garfield County Vegetation Management - December 11, 2006- Steve Anthony and I discussed the project via phone. Steve indicated that he would review the application after receiving it and will comment. Please see attached the "Cottonwood Compressor Station to Webster Hill 24" Gathering Line Rehabilitation Plan 4/30/07." This rehabilitation plan includes the gathering line and the Rabbit Brush and Webster Hill compressor stations. Please also find attached an "Integrated Vegetation and Noxious Weed Management Plan" for the project prepared by WestWater Engineering. Steve Anthony noted that he will need a quantity of the acreage to be disturbed to set forth the revegetation bond for the project. It is anticipated that this bond would be released after 2 growing seasons. Page 1 of 2 The disturbed area is determined using the following method: Summary ROW Length and Acreage Totals For Federal and Fee Lands 24" Trunk Line and 12" Jumper Lines Two Compressor Stations 24" Bargath Gather ng Pipeline Pro'ect Bargath Inc. % Williams Production RMT Company Owner Length LF Permanent ROW 50' Acres Construction ROW 75' ACRES Extra Workspace at 9% Total Acres Total Surface Area Acres Federal Lands 7,298 8.38 12.57 1.24 13.81 Fee and CDOT Lands 47,484 54.50 81.76 8.09 89.84 Total Lands for Pipelines 54,782 62.88 94.33 9.33 103.65 Lands for Stations — All Fee 28.52 Total Acreage Fee, CDOT Lands: 89.84 acres. Total Acreage Fee lands for Rabbit Brush and Webster Hill compressor stations: 28.52 Total Acreage: 118.36 acres We are prepared to post a reclamation/revegetation bond for the 118.36 acres disturbed. In 2006 Bargath, Inc. posted a reclamation/revegetation bond for the Cottonwood Compressor Station to Parachute Creek Gas Plant 30" gathering line and the Noble to Parachute 12" Gathering Line for $2,500 per acre and we are prepared to do the same for this project. Please contact me with any questions. Sincerely, ( Philip B. Vaughan President PVCMI Page 2 of 2 COTTONWOOD COMPRESSOR STATION TO WEBSTER HILL 24 INCH GATHERING LINE REHABILITATION PLAN 4/30/007 The Cottonwood Compressor Station to Webster Hill 24 inch gathering line will be located on rangeland owned by numerous owners. The length of the pipeline is approximately 8.3 miles in length. In addition there are 4-12.75" jumper lines connected from the 24" pipeline to the existing Anvil Points Compressor Station (68.80'), existing Rulison Compressor Station (4,417.80'), existing Sharrard Compressor Station (2,308.40') and existing Clough Compressor Station (493.90). These 4 jumper lines have a combined length of 7,288.90 feet or 1.38 miles. The soil should be stripped to a depth of approximately twelve (12) inches and stockpiled at the edge of the disturbed right-of-way. The maximum depth of stockpile shall be 24" or less to preserve soil viability. The expected duration of the project is 10 to 12 weeks. Topsoil stockpiles shall be preserved and water applied to prevent wind erosion. RECLAMATION Areas disturbed by construction will be reclaimed no later than October, 2007, following pipeline construction. The objectives of reclamation will be as follows: 1. Stabilization of the disturbed areas will be conducted by providing wind and water erosion control to reduce soil loss. The stormwater management plan for the project shall be adhered to. 2. Utilize the prescribed seed mixtures and additional vegetation practices as described below to establish a self- sustaining vegetative rangeland cover. PIPELINE ABANDONMENT The pipeline will be abandoned in accordance with Colorado Oil and Gas Conservation Commission regulations in place at the time of abandonment. BACKFILLING, GRADING, AND RE -CONTOURING Reclaimed areas will be sloped as per the project drawings and specifications. Page 1 of 7 TOPSOIL REPLACEMENT Soil salvaged during construction activities will be redistributed over the soil surface after subsoil has been replaced and dditional backfilling; grading, and re -contouring steps have been completed as described below. Soil will be replaced by using front-end loaders, trackhoes, and dozers. Soil will not be replaced when it is excessively wet and/or frozen. SEEDBED PREPARATION / SOIL TILLAGE Seedbed preparation and soil tillage will be completed after the application of subsoil, topsoil, and any soil amendments. Soil tillage will be to a minimum depth of 4" utilizing a disk, chisel plow, or harrow. Seedbed preparation will also include removal of coarse fragments (rock material) that exceed 35% to 40% of the soil surface as well as rocks 8" in diameter that occupy more than 10% of the soil surface. SEEDING METHODS AND TIMES If seeding is performed in the spring, it will be accomplished by May 15; if fall seeding is performed it will be completed after August 30 and before the soil freezes. Seeding efforts will consist of drill seeding with a rangeland drill to a planting depth of to %' on slopes 3:1 or flatter. Broadcast seeding followed by harrowing or hand raking to lightly cover the seed with soil will be used on slopes steeper than 3:1, or on areas inaccessible for drill seeding equipment. \II areas to be reclaimed will be mulched no later than 24 hours after seeding with a certified weed -free straw or grass hay material. Grass hay mulch will be applied at 1 '% tons per acre, or straw mulch will be applied at 2 tons per acre. Mulch material will be crimped into the soil surface with a commercial mulch crimper, a straight disc, or bulldozer tracks if too steep to otherwise crimp mulch in place. Seed tags shall be retained after planting and submitted to the Garfield County Vegetation Manager to verify the seed mixture and the quantity of seed planted. SEED MIXTURES Please see Table 1 for the seed mixtures. WEED CONTROL PLAN Prior to construction, a qualified person will inspect the proposed right-of-way and will inventory and map the proposed project area for any listed Garfield County noxious weeds. Based on this inventory and mapping, methods, materials, and timing of weed control measures will be specified. During the life of the pipeline operation, the operator will be obligated to regularly inspect the right-of-way and to inventory and treat any listed Garfield County noxious weeds. Page 2 of 7 TABLE 1 Final Reclamation Seed Mixture Common Name Scientific Name Pounds Pure Live Seed (PLS) per acre Alkali Sacaton Sporobolus airoides 1.0 Sideoats Grama Bouteloua curtipendula 2.0 Basin Wildrye Leymus cinereus 2.0 Westem wheatgrass Pascopyrum smithii 4.0 TOTAL PLS 9.0 Page 3 of 7 SITE REHABILITATION PLAN WEBSTER HILL COMPRESSOR STATION AND RABBIT BRUSH COMPRESSOR STATION 4/30/07 r.he Webster Hill Compressor Station will be located on rangeland owned by the Estate of William F. Clough. The Webster Hill Compressor Station area is 15.27 acres. The subject site appears to lie in the Arvada-Torrifluvents-Heft soil series as shown on the Garfield County Generalized Soils Types map dated 1/31/02. These soils are better classified as a sandy, silty clay (CL) under the Unified Classification System. This soil is a stratified colluvial/debris flow soils which originate on the upper slopes to the North, stratified with alluvial soils deposited by the ancient Colorado River feature. The Rabbit Brush Compressor Station will be located on rangeland owned by ExxonMobil. The Rabbit Brush Compressor. Station area is 14.30 acres. The subject site appears to lie in the Arvada-Torrifluvents-Helt soil series as shown on the Garfield County Generalized Soils Types map dated 1/31/02 These soils are better classified as a sandy, silty clay (CL) under the Unified Classification System. This soil is a stratified colluvial/debris flow soils which originate on the upper slopes to the North, stratified with alluvial soils deposited by the ancient Colorado River feature. The soil should be stripped to a depth of approximately twelve (12) inches and stockpiled at the facility margins. The maximum depth of stockpiled shall be 24" or less to preserve soil viability. Topsoil stockpiles will be seeded as described below in the section on seeding methods and times. RECLAMATION Two phases of reclamation are planned. Soil stockpiles and areas disturbed by construction that will not be utilized during the compressor station construction operation will be reclaimed immediately following construction. Final reclamation will be performed within one year of compressor station closure and removal. The objectives of reclamation will be as follows: 1. Stabilization of the disturbed areas will be conducted by providing wind and water erosion control to reduce soil loss. 2. Utilize the prescribed seed mixtures and additional vegetation practices as described below to establish a self- sustaining vegetative rangeland cover for cattle pasture use. Page 4 of 7 FACILITY AND STRUCTURE REMOVAL The compressor stations will be abandoned in accordance with Colorado 00 and Gas Conservation Commission egulations in place at the time of facility abandonment. Equipment will be removed from the site. BACKFILLING, GRADING, AND RE -CONTOURING Reclaimed areas will be sloped to 3:1 or less. Page 5 of 7 TOPSOIL REPLACEMENT Soil salvaged during construction activities will be redistributed over the soil surface after subsoil has been replaced and additional backfilling; grading, and re -contouring steps have been completed as described below. Soil will be replaced by using front-end loaders, trackhoes, and dozers. Soil will not be replaced when it is excessively wet and frozen so as to jeopardize soil structure. SEEDBED PREPARATION/SOIL TILLAGE Seedbed preparation and soil tillage will be completed after the application of subsoil, topsoil, and any soil amendments. Soil tillage will be to a minimum depth of 4" utilizing a disk, chisel plow, or harrow. Seedbed preparation will also include removal of coarse fragments (rock material) that exceed 35% to 40% of the soil surface as well as rocks 8" in diameter that occupy more than 10% of the soil surface. SEEDING METHODS AND TIMES Soil stockpiles and areas disturbed by construction that will not be utilized during compressor station operation will be seeded. If seeding is performed in the spring, it will be accomplished by May 15; if fall seeding is performed it will be completed after August 30 and before the soil freezes. Seeding efforts will consist of drill seeding with a rangeland drill to a planting depth of IA" to 'A" on slopes 3:1 or flatter. Broadcast seeding followed by harrowing or hand raking to lightly ;over the seed with soil will be used on slopes steeper than 3:1, or on areas inaccessible for drill seeding equipment. All areas to be reclaimed will be mulched no later than 24 hours after seeding with a certified weed -free straw or grass hay material. Grass hay mulch will be applied at 1 %z tons per acre, or straw mulch will be applied at 2 tons per acre. Mulch material will be crimped into the soil surface with a commercial mulch crimper, a straight disc, or bulldozer tracks if too steep to otherwise crimp mulch in place. Seed tags shall be retained after planting and submitted to the Garfield County Vegetation Manager to verify the seed mixture and the quantity of seed planted. SEED MIXTURES Please see Table 1 for the seed mixtures. Page 6 of 7 WEED CONTROL PLAN A qualified person will inspect the compressor station sites and will inventory and map the proposed project area for any listed Garfield County noxious weeds. Based on this inventory and mapping, methods, materials, and timing of weed control measures will be specified. The vast majority of compressor station area will be graveled and will be devoid of vegetation. Bargath, Inc. reserves the right to modify this plan based on Best Available Technology (BAT) at the time of compressor station closure. TABLE 1 Stockpile and Disturbed Areas Reclamation Common Name Scientific Name Pounds Pure Live Seed (PLS) per acre Western wheatgrass Pascopyrum smithii 8.0 Sideoats Grama TOTAL PLS 8.0 TABLE 2 Final Reclamation Seed Mixture ;ommon Name Scientific Name Pounds Pure Live Seed (PLS) per acre Alkali Sacaton Sporobolus airoides 1.0 Sideoats Grama Bouteloua curtipendula 2.0 Basin Wildrye Leymus cinereus 2.0 Western wheatgrass Pascopyrum smithii 4.0 TOTAL PLS 9.0 Page 7 of 7 Bargath Cottonwood Gulch to Webster Mesa 24 Inch Gathering Pipeline System Webster Hill and Rabbit Brush Compressor Stations Integrated Vegetation and Noxious Weed Management Plan Garfield County, Colorado Prepared for: Bargath, Inc. C/O Williams Production RMT Parachute, CO Prepared by: WestWater Engineering 2570 Foresight Circle #1 Grand Junction, CO 81505 April 2007 Bargath Cottonwood Gulch to Webster Mesa 24 Inch Gathering Pipeline Webster Hill and Rabbit Brush Compressor Stations Integrated Vegetation and Noxious Weed Management Plan April 2007 Introduction A field inspection of the Bargath Cottonwood to Webster Mesa pipeline alignment and proposed compressor station sites was conducted by WestWater Engineering (W WE) biologists. The inspection identified appropriate topics for inclusion in an integrated vegetation and noxious weed management plan required by Garfield County Regulation 9.07.04 (13) (Board of County Commission 2006). Factors considered include soil type and texture, existing land management, absence or presence of listed noxious weeds and natural vegetation community. Pipeline and Compressor Survey Area and Landscape Setting The 24 inch pipeline will constructed beginning on Webster Mesa west of Rifle, Colorado, and join with an existing Williams 30 inch pipeline near the lower end of Cottonwood Gulch west of Rulison, Colorado (Figure 1). The pipeline generally runs in an east -west direction parallel to and north of Interstate Highway 70. The vegetation is generally composed of piflon juniper woodland and mixed sagebrush/greasewood shrublands (Figure 2). ,: Figure 2. Typical terrain and vegetation communities on Webster Mesa WestWater Engineering Page 1 of 12 April 27, 2007