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LEGEND
<br />A --�- SS EXISTING SANITARY SEWER
<br />- - - - - PERMIT BOUNDARY
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<br />s
<br />PROPOSED HAUL ROAD - - - - - EXISTING 5 FOOT CONTOUR
<br />' • -----
<br />�,• ` �
<br />IRRIGATION DITCH - - - - - - - -EXISTING 25 FOOT CONTOUR
<br />L 71.341A f, - PIROPOSED MINING LIMITS
<br />SLURRY WALL
<br />I - - EXISTING PARCELS
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<br />' �t`b 100 YR EFFECTIVE FLOOD PLANE O w
<br />PERMIT BOUNDARY (TYP) -Y --�- cM v�
<br />"f EXISTING DITCH
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<br />' �- _ . ` 100 YR PRELIMINARY FLOOD PLANE
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<br />1 � G EXISTING .ISTING GAS LINE P100 -YR
<br />rc 100 YR PROPOSED FLOOD PLANE
<br />' E:XISTING OVERHEAD ELECTRIC A,00-vn
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<br />NOTES ND USE APPROVED BY THE CITY OF LONGMONT.
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<br />CULVERT t amu' l
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<br />_r �$ ___� `��,,�•� `�`� ,-" :'r � -.,�`' f �° �;� -' �" � �' `'' 1. THE PROPOSED FINAL LANID USES FOR THE IRWIN/THOMAS MINE ARE GENERAL AGRICULTURE OR LA
<br />I
<br />^�` �� ��� ^r T' ' - AGRICULTURAL USES SHAILL BE LIMITECI TO CROP PRODUCTION AND MAY NOT INCLUDE ANY LIVESTOCK. ,,u
<br />�`� `' _ �'`� _ ' "' a �`` _ t•ry = " ` �' S WHEN ADEQUATE QUANTITIES OF OFF-SITE BACKFILL MATERIAL ARE AVAILABLE AND A o
<br />2. RECLAMATION PLAN MAP ILLUSTRATES CONDITION
<br />ILL BE
<br />ANENT SOURCE OF WATER FOR LONG TERM AUGMENTATION OF EXPOSED GROUNDWATER HAS BEEN OBTAINED. MINED CELLS W
<br />cryo . )` `-- _. POND F PERM
<br />�- -------- �{T � BACKFILLED TO CREATE UPLANDS, OPEN WATER PONDS AND LIMITED WETLAND AREAS.
<br />?h _ ` • r 1.3 AC - >?--A - --� - ----- -^ - - THE VRAIN CREEK DELINEATED F100 YEAR FLOODPLAIN SHALL BE GRADED TO m
<br />oy 11�jl _3. ALL SLOPES SHALL BE GRADED TO 3HAV OR FLATTER. SLOPES WITHIN T NEr UGH GRADING WIILL ESTABLISH FINAL ELEVATIONS, SLOPES, AND TRANSITIONS. TRANSITIONS BETWEEN UPLANDS, WETLANDS, ANDWETLAND `� 4.1 OR FLATTER. RO8.7 AC - _SII , �€;t - UAL TOPOGRAPHY.
<br />_/�,tr.l POND SLOPES SHALL BE G RADED WITH A SMOOTH, GRAD TO DRAWN PDB
<br />IRRIGATION DITCH a,st;:..
<br />_ 4. FINAL GRADING WILL INCLUDE ADDITION OF TOPSOIL AND SURFACE PREPARATION FOR REVEGETATION. SPECIAL ATTENTION SHALL BE GIVEN
<br />;Arm,. TSD_ _- `' ��= - '--' - - TRANSITIONS FROM RECLAIMED AREAS TO UNDISTURBED LAND. CHECKED
<br />�4 _l t
<br />BW
<br />tf� , --�� 8.3 AC 5. ALL AVAILABLE AND OVERBURDEN MATERIAL WILL BE USED FOR BACKFILLING AND RECLAMATION.
<br />PERMIT BOUNDARY (TYP) r' I _ _ ~' _� E - i +++ �� '
<br />_ DESIGNED
<br />r , ,; 6. THE GROWTH MEDIUM POR REVEGETATION WILL BE A COMBINATION OF OVERBURDEN AND TOPSOILS.
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<br />• -"` '` -� � 7. TWO DIFFERENT MIXES OIF UPLAND GRASSES WILL BE USED IN AREAS THAT WILL NOT EXPERIENCE PERIODIC FLOODING, SEASONAL GROUNDWATER,
<br />ED SIMPLY FOR QUICK SOIL STABILIZATION AND EROSION CONTROL THIS MIX WILL FILENAME
<br />OR OTHER MOIST SOIL CONDITIONS. ONE SEED MIX WILL BE USED 01 DRMS
<br />-! l+ d"� .-' r _ _ -'� _s _ -- A , ''- ..'�•� DEVELOPMENT IS EXPECTED TO OCCUR FOLLOWING PERMIT RELEASE. THE
<br />_ �.._ 1241 00
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<br />-- - _
<br />�``.�---� --� MAINLY BE USED IN MA1 WHERE FURTHER AGRICULTURAL OR OTHER
<br />RECLAIM GROUNDWATER "- " r� <` z �- -• ��-�--�-�-LL '" '�"'`"'� `�... '�-�- "1 I �' � FT AS OPEN SPACE IS COMPOSED OF A LONG LASTING AND REGENERATING NATIVE UPLAND SEED MIXTURE
<br />.- --- -- � �f:,fiF '`'�"•a I I + SECOND GRASS SEED MIS FOR AREAS LE
<br />, '� ST V
<br />DISCHARGE TO CREEK PER ,r.
<br />I RAIN CR
<br />- RECLAIM GROUNDWATER , ' `:, `''�, ; " i i `
<br />� • ` ^�w,� EFK - � �-~ "" -~ Upland Grass Seed -Native Open Space Application Rate" (#PLS/acre)
<br />MINING PLAN
<br />_ wW DISCHARGE TO CREEK PER - f I I . A
<br />_:_ _s - A WETLAND PLAN -,.� - �`'�+� Western Wheatgrass 1
<br />4.2 AC. MINING Blue rama
<br />„rte e� ND gr 1.5
<br />d r ST. VRA '�,�„ ---- - :. �'' T -:, ` ri, 1 "cd
<br />�IVETLA : -��� ;
<br />__ w
<br />Side oafs gra
<br />4 AC
<br />_ �.i Switchgrass
<br />GREENWAY Iy --•;
<br />.
<br />R YR _ Sand n Ri seed 1
<br />0.5
<br />NF`
<br />3, t�--�.� • �,� _ 4�0 � '(I Indian Ricegrass
<br />3
<br />v f{
<br />_ TOTAL 9
<br />- ~'P POND C�� POND D '�.. A'`� `'>�F._ *Application rate is for drill seeding. If seed is to be broadcast. The
<br />aLl 8.4 ACRES ► atr P100- application ratewill bedoubled.
<br />E100 -vg- j 8.5 ACRES '�� ST'�, : mrr?
<br />P70o-YR
<br />0 o;
<br />-;,$ DISCHARGE TO
<br />91,30 YR CREEK PER
<br />8A-ootd ��J ROW MINING PLAN ,r
<br />a�-oo ld dA oo ld ,o -
<br />- t
<br />E. KEN PRATT BL
<br />/ SS- SS S SS�� -- -- `J PROVIDE ENHANCED'
<br />_ s
<br />(HWY 119)- I - -
<br />RIPARIAN R
<br />-- + ANA AREA
<br />EX. SANITARY SEWER n1oo=YR c� a
<br />x
<br />n .� `� I STORM DRAINAGE i, Z'
<br />EX. STORM SEWER oo` CHANNEL -
<br />Upland Grass Seed -Soil Stabilization Application Rate" (#PLS/aae)
<br />Intermediate Wheatgrass
<br />3
<br />Blue
<br />8. IN AREAS WHERE WETLANDS COULD POTENTIALLY BE DEVELOPED, THE SEED MIXTURE WILL BE MODIFIED TO INCLUDE MORE TRANSITION AND
<br />WETLAND GRASSES AND GRASS -LIKE SPECIES. THESE SEED MIXES, ESPECIALLY IF STANDING WATER OR SATURATED SOILS EXIST DURING PLANTING, WILL
<br />LIKELY NEED TO BE BROADCAST. RECEIVED
<br />Wetland/Transition Grass Seed
<br />Application Rate" (#PLS/acre)
<br />Western wheatgrass
<br />2.5
<br />Gra ma
<br />0.75
<br />Alfa I fa
<br />0.75
<br />TOTAL
<br />4.5
<br />*Application rate is for drill) seeding.If seed is to be broadcast.The
<br />application ratewill bedowbled.
<br />Meadow sedge
<br />8. IN AREAS WHERE WETLANDS COULD POTENTIALLY BE DEVELOPED, THE SEED MIXTURE WILL BE MODIFIED TO INCLUDE MORE TRANSITION AND
<br />WETLAND GRASSES AND GRASS -LIKE SPECIES. THESE SEED MIXES, ESPECIALLY IF STANDING WATER OR SATURATED SOILS EXIST DURING PLANTING, WILL
<br />LIKELY NEED TO BE BROADCAST. RECEIVED
<br />Wetland/Transition Grass Seed
<br />Application Rate" (#PLS/acre)
<br />Western wheatgrass
<br />2.5
<br />Switchgrass
<br />2.5
<br />Bottlebrush squirreltail
<br />1.5
<br />Alkali sacaton
<br />1.5
<br />Colorado rush
<br />1.5
<br />Meadow sedge
<br />1.5
<br />Tota 1
<br />11
<br />*Application rate is for drill seeding. If seed is to be broadcast. The
<br />application rate will be doubled.
<br />[SEC 19 2ozz
<br />OIV MIN NOF t,N
<br />G AND ���
<br />100 YR PRELIMINARY
<br />FLOODPLAIN 9 AC B
<br />• � 14.9 ACRES ` 9 WITH CDERTIFIED WEED -LESS (LESWILL S STRAW MUE PLANTED LCH AT A RATE OFTH A DRILL 12,000 OPPED IUNDS PER ACRTH DEPTH E THE DSTRAW WILL BE CRIMPED NPRESS WHEELS. THE DTO THE SOAREA IIL O CONTROL
<br />LL THEN BE ER
<br />20190930 FIRM 0801CO289K a
<br />` WETLAND , POTENTIAL SLURRY WALL - ENGINEERED DESIGN EROSION UNTIL THE GRASS BECOMES ESTABLISHED:
<br />- 4 -� 100 YR EFFECTIVE '` TO BE SUBMITTED TO DRMS FOR APPROVAL 10. DRILL SEEDING IS THE PREFERRED METHOD FOR REVEGETATION. IF BROADCAST SEEDING IS NECESSARY ON MOIST SOILS, STEEP SLOPES, OR INUj
<br />�r
<br />FLOODPLAIN r � EXCESSIVELY ROCKY AREAS, SUCCESS CAN BE ENCOURAGED BY BROADCASTING ONTO GROWTH MEDIUM THAT IS VERY LOOSE. IF THE SEED IS
<br />C( I POND A 20121218 FIRM 0801 CO289JQ
<br />15.2 ACRES , UNINCORPORATED BROADCAST IN THOSE CIRCUMSTANCES, THEN THE SEEDED AREA WILL BE DRAGGED TO HELP BURY THE SEED.
<br />dcr 11. PERIODIC INSPECTION FOR NOXIOUS WEEDS, AT LEAST ONCE A QUARTER, AND MORE FREQUENTLY AS NEEDED, WILL BE DONE AS PART OF A WEED J
<br />I BOULDER COUNTY MANAGEMENT PLAN.
<br />AGRICULTURE
<br />q��` = I j 12. THE MINE OFFICE/SCALE HOUSE TRAILER AND ANY OTHER STRUCTURES ASSOCIATED WITH MINING WILL BE REMOVED FROM THE SITE DURING FINAL
<br />cj�C W U. z
<br />� � � RECLAMATION ACTIVITIES.
<br />13. BEST MANAGEMENT PRACTICES WILL BE USED TO CONTROL EROSION AND STORMWATER SUSPENDED SEDIMENT RUNOFF FROM THE SITE DURING Q
<br />t
<br />AREA TO BE RECLAIMED TO RECLAMATION ACTIVITIES.
<br />I - UPLAND AND REVEGETATED
<br />I BONUS DITCH ALIGNMENT � ,
<br />AS PART OF THE MLRB
<br />RECLAMATION PLAN. �` 100 YR EFFECTIVE FLOODPLAIN".' x POND LINER NOTES
<br />20121218 FIRM 0801CO289 ---
<br />- - - - - - - - - � _ - - - ---- -- -- - - .-_ 1. PRIOR TO CONSTRUCTION, OVERBURDEN AND CLAYSTONE MATERIAL TESTING SHALL BE PERFORMED FOR USE IN FINAL DESIGN. THE FOLLOWING
<br />� QUICKSILVER RD ,.� SPECIFICATIONS AND PROCEDURES ARE PROVIDED AS A GENERAL GUIDELINE FOR PERMITTING PURPOSES. FINAL SPECIFICATIONS AND DESIGN CRITERIA � � a
<br />!, �s3, ,� p100.YR NA-Ap X100-1m
<br />P100 WILL BE DEVELOPED DURING THE FINAL DESIGN PROCESS. Z W
<br />I �
<br />� 2. EACH LAYER OF FILL SHALL BE SCARIFIED TO ALLOW PROPER BONDING BETWEEN LAYERS.
<br />Ar �
<br />THIS AMENDMENT REMOVES THIS 100 YR PROPOSED FLOODPLAIN - ,
<br />� ,� LONGMONT FLOODPLAIN APPEAL _ 3. DENSITY AND MOISTURE CONTENTTESTING SHALL BE PERFORMED AT A RATE OF 1 TEST FOR EACH 2,000 YARDS PLACED. W
<br />PORTION OF THE PERMIT AREA �R 4. ALL CLAY LINER MATERIAL SHALL BE COMPACTED TO A MINIMUM 95% ASTM -D698-78 STANDARD PROCTOR AT OF OPTIMUM MOISTURE CONTENT.
<br />FOR DEVELOPMENT IN THE CITY -_ o
<br />�� P °
<br />� � yR �
<br />o
<br />y 5. NO LINER MATERIAL SHALL BE PLACED IN THE LINER SLOPE WHILE EITHER THE MATERIAL, EMBANKMENT, OR FOUNDATION IS FROZEN.
<br />OF LONGMONT
<br />$ AREA TO BE RIECLAIMED TO
<br />AS PART OF UPLAND AND REVEGETATED P100 -YR 6. NO ORGANIC MATERIAL SHALL BE PLACED IN THE LINER SLOPE.
<br />® oo ' HE MLRB 7. EACH LAYER OR LIFT SHIALL BE CONSTRUCTED CONTINUOUSLY AND APPROXIMATELY HORIZONTAL FOR THE WIDTH AND LENGTH OF EACH LIFT.
<br />' SS a d RECLAMAT O ' PLAN.
<br />�R 8. LINER MATERIAL SHALL BE COMPOSED OF CLAYEY OVERBURDEN AND WEATHERED CLAYSTONE THAT BREAKS DOWN DURING PROCESSING. BEDROCK
<br />Q I �� i e1°o-
<br />CLAYSTONE MATERIAL MAY BE RIPPED, MOISTURE TREATED, AND ALLOWED TO AIR SLAKE FOR A MINIMUM OF ONE DAY PRIOR TO ITS PLACEMENT IN
<br />I ® I I
<br />��-oofd THE LINER. LINER MATERIAL IS DEFINED AS MATERIAL HAVING 4 INCH OR SMALLER COBBLE, A MINIMUM OF 50% FINES BY CLAY WEIGHT PASSING THE US
<br />• • I�V $ STANDARD 200 SIEVE, AND A PLASTICITY INDEX OF 10% OR GREATER FOR THE PORTION OF MATERIAL FINER THAN THE US STANDARD 40 SIEVE.
<br />+ �1
<br />�
<br />�� I I� � ,i 'I �II � "`" :...,_ �.. 9. SU SPECIFICATIONS ONCE PLACED IN THE FILDOE RROW AREA SO NO MORE THAN 3% ADDITIONAL MOISTURE IS REQUIRED TO BRING ANY LINER
<br />II I o. MATERIAL TO PEC
<br />N � W �I iI� �- a� � 10. LINER MATERIAL SHALL BE PLACED IN MAXIMUM OF 9 -INCH LOOSE LIFTS PRIOR TO COMPACTION.
<br />N
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<br />�I i 11. A CATERPILLAR 815 OR 825 SHEEPSFOGT COMPACTOR (OR EQUIVALENT) WILL BE USED FOR COMPACTING EFFORTS.
<br />N II.•.,,, `'r 12. THE COMPLETED LINER SHALL BE PROTECTED FROM DAMAGE CAUSED BY DESICCATION OR FREEZING TEMPERATURES BY PLACING A MINIMUM OF
<br />Lif
<br />to �� �I EXISTING RURAL " "r;.> 12 -INCHES PIT RUN MATERIAL ON THE ENTIRE SLOPE.
<br />�Ij ( EXISTING RURAL
<br />f�0 '') RESIDENTIAL s RESIDENTIAL +`' r 13. LINED PONDS SHALL PASS LEAK TEST AS REQUIRED BY THE COLORADO OFFICE OF THE STATE ENGINEER AND COLORADO DIVISION OF WATER
<br />RESOURCES
<br />READ_
<br />I�• ,- 3H 7t - - - - ..
<br />� - _ - - _-�IJ�c�A��e - - _ ` - _- _ � SLURRY WALL LINER NOTES
<br />Q BOULDER COUNTY
<br />/ 0 150' 300' 600' 1. PONDS 1 AND 2 MAY BE SEALED WITH A SLURRY WALL LINER AS AN ALTERNATIVE TO THE COMPACTED CLAY LINER AS DESCRIBED IN POND LINER NOTES
<br />AGRICULTURE = 1-13.
<br />2 INSTALLATION, SITE SPECIFIC ENGINEERED DESIGN AND SPECIFICATION FOR THE S R
<br />`i NORTH SCALE' 1" 30 ' SLURRY WALL WILL BE SUBMI
<br />TIED TO THE DIVISION FOR
<br />O � `. PRIOR TO IN N, S
<br />MINING HIGH WALL 41 SLOPE TO MEET 4 t OR SHALLOWER SLOPE Area approximately 1.5 acres. Install - 50 Plains Cottonwood (5 gallon). Install irregular clusters, with APPROVAL
<br />GRADE AT TDP OF WIDTH '& GRADIENT VARIES irregular open grass areas: 100 Western Sand Cherry (rooted cuttings), 100 American plum (rooted
<br />N 6" TOP SOIL AVERAGE NORMAL BANK. UPLAND SEED cuttings), 100 Three Leaf Sumac (rooted cuttings). Install plantings, seed and mulch area. 3. LINED PONDS SHALL PASS LEAK TESTAS REQUIRED BY THE COLORADO OFFICE OF THE STATE ENGINEER AND COLORADO DIVISION OF WATER
<br />C.
<br />HISTORIC GROUND g g
<br />HISTORIC GROUND GROUNDWATER Irrigate to establish plantings and employ comprehensive weed management to establish upland seed. RESOURCES. T$T, IN
<br />J OVERBURDEN BACKFI - SURFACE MINING HEADWALL
<br />CONSULTING ENGINEERS
<br />N -� SOIL/OVERBURDEN f ^€ �. APPLY WETLAND FLOOD PLAIN NOTES 748 Whalers Collinsy
<br />3' MINING SLOPE AND UPLAND 12" TOPSOIL Suite 200 Fort C
<br />.. j 6" TOPSOIL SEED FLOODPLAIN INFORMATION PER FIRM FLOOD INSURANCE RATE MAP NO 08013CO287J DATED DECEMBER 18, 2012 AND FIRM FLOOD INSURANCE RATE MAP
<br />T Colorado 80525
<br />N 15,_20, f2" TOPSOIL NO 08013CO289J DATED DECEMBER 18, 2012. Phone: 970.226.0557
<br />JOB N0.
<br />/
<br />SAND/GRAVEL z AVERAGE NORMAL • THIS PROPERTY LIES IN AREAS DETERMINED TO BE WITHIN 1241.0001.02
<br />WATER SURFACE
<br />OTHER AREAS - AREAS OUTSIDE THE 2% ANNUAL CHANCE FLOOD
<br />E4' ZONE X - AREAS OF 25 % ANNUAL CHANCE OF FLOOD OR AREAS WITH 1% ANNUAL CHANCE OF FLOOD WITH AVERAGE DEPTHS OF LESS THAN ONE FOOT SCALE 1"=300'
<br />'o : f:
<br />i
<br />BACKFILL
<br />OR WITHIN DRAINAGE AREAS LESS THAN ONE SQUARE MILE AND AREAS PROTECTED BY LEVEES FROM THE 100 YEAR FLOOD.
<br />MINING HIGHWALL • ZONE AE -SPECIAL FLOOD HAZARD AREAS SUBJECT TO INUNDATION BY THE 1% ANNUAL FLOOD CHANCE, BASE FLOOD ELEVATIONS DETERMINED.
<br />U OVERBURDEN GRADED OTO DRAIN ZONE AH - SPECIAL FLOOD HAZARD AREAS SUBJECTTO INUNDATION BY THE 1% ANNUAL FLOOD CHANCE, FLOOD DEPTHS OF 1 TO 3 FEET, (USUALLY DAZE DECEMBER 2022
<br />/ SHORELINE WETLAND BENCH AREAS OF PONDING) BASE FLOOD ELEVATIONS DETERMINED. sHEET
<br />0 MINING SECTION C (DIAGONAL HATCH)
<br />O POND RECLAMATION SLOPE TO WIDTH VARIES, APPROXIMATEY 1.5 ACR
<br />/ ,.-, "n �T rrx°nIRREGULAR GRADE, MATCH TO FINISHED GRADE AT EDGES THE ADDITIONAL FLOODPLAINS SHOWN ARE BASED ON PRELIMINARY FEMA FIRM MAP 08013CO289K FROM SEPTEMBER 30, 2019 AND LONGMONT S APP of
<br />OF FEMA'S PRELIMINARY FIRM MAP. THESE MAPS ARE NOT FINAL AND ARE EXPECTED TO BE REVISED, THESE ARE SHOWN
<br />(V
<br />SHORELINE RECLAMATION ENHANCED RIPARIAN AREA FOR INFORMATIONAL PURPOSES ONLY.
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