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TESC CONSTRUCTION SEQUENCE
1. ATTEND PRE-CONSTRUCTION MEETING.
2. INSTALL CATCH BASIN PROTECTION.
3. INSTALL PERIMETER PROTECTION (SILT FENCE, NPGA AREAS, BRUSH
BARRIER, ETC.)
4. CONDUCT SITE CLEARING AND GRADING.
5. INSTALL DRAINAGE FACILITIES AND OTHER UTILITIES.
6. COMPLETE PROJECT PER THE PROJECT PLAN
7. MAINTAIN EROSION CONTROL MEASURES IN ACCORDANCE WITH LOCAL
JURISDICTION
REQUIREMENTS AND MANUFACTURER'S RECOMMENDATIONS.
8. RELOCATE SURFACE WATER CONTROLS OR EROSION CONTROL MEASURES,
OR INSTALL
NEW MEASURES SO THAT AS SITE CONDITIONS CHANGE, THE EROSION AND
SEDIMENT
CONTROL IS ALWAYS IN ACCORDANCE WITH LOCAL JURISDICTION
REQUIREMENTS.
9. COVER ALL AREAS THAT WILL BE UNWORKED FOR MORE THAN TWO DAYS
BETWEEN
OCTOBER 1ST AND APRIL 30TH OR SEVEN DAYS BETWEEN MAY 1ST AND
SEPTEMBER 30TH.
10. STABILIZE ALL AREAS WITHIN SEVEN DAYS OF REACHING FINAL
GRADE.
11. SEED OR SOD ANY AREAS TO REMAIN UNWORKED FOR MORE THAN 30
DAYS.
12. UPON COMPLETION OF THE PROJECT, STABILIZE ALL DISTURBED
AREAS AND REMOVE
TEMPORARY BMPS.
DEWATERING PLAN
DEWATERING DISCHARGE
CONTRACTOR SHALL DESIGN, PROVIDE, INSTALL, OPERATE AND MANAGE
DEWATERING DISCHARGE
FACILITIES TO ACCOMMODATE THE ENCOUNTERED FLOWS IN A MANNER THAT
WILL PREVENT EROSION.
THE CONTRACTOR SHALL NOT ALLOW THE WATER DISCHARGED FROM ANY
DEWATERING SYSTEM
WELLS OR SUPPLEMENTAL WATER CONTROL SYSTEMS (I.E. SUMPS) TO
DEGRADE THE WATER QUALITY
OF ANY RECEIVING WATERS.
THE DEWATERING DISCHARGE SYSTEM SHALL OPERATE SUCH THAT WATER
PUMPED DURING
DEWATERING OPERATIONS IS DISCHARGED TO ADJACENT LANDS FOR
INFILTRATION AND/OR
CONTROLLED OVERLAND FLOW. THE SYSTEM SHALL DISPOSE OF WATER SO
AS NOT TO CAUSE
DAMAGE TO PUBLIC OR PRIVATE PROPERTY, TO CAUSE EXCEEDANCES OF
WATER QUALITY STANDARDS
OR TO CAUSE A NUISANCE OR MENACE TO THE PUBLIC.
ALL DEWATERING DISCHARGE POINTS SHALL BE A MINIMUM OF 100 FEET
FROM ANY CREEK OR DITCH.
CONTRACTOR SHALL OBTAIN ACCESS PERMISSION FROM PRIVATE PROPERTY
OWNERS FOR ANY
DISCHARGE.
THE DEWATERING DISCHARGE SYSTEM SHALL MAINTAIN WATER QUALITY
STANDARDS FOR SURFACE
WATERS BY PERFORMING IN COMPLIANCE WITH CHAPTER 173-201A WAC,
WATER QUALITY STANDARDS
FOR SURFACE WATERS OF THE STATE OF WASHINGTON, AND ALL REQUIRED
PERMITS, INCLUDING BUT
NOT LIMITED TO THE NATIONAL POLLUTANT DISCHARGE ELIMINATION
SYSTEM GENERAL PERMIT FOR
CONSTRUCTION ACTIVITY.
THE CONTRACTOR SHALL INSTALL, OPERATE, AND MAINTAIN A WATER
TREATMENT SYSTEM TO PROVIDE
FOR SETTLING, FILTRATION (IF NEEDED) AND REMOVAL OF SUSPENDED
SOLIDS IN THE DISCHARGE
FROM THE DEWATERING SYSTEM.
THE DISCHARGE SYSTEM MAY CONSIST OF ANY COMBINATION OF
CONVEYANCE PIPING, VISQUEEN
PADS, FILTER BAGS, DRIP IRRIGATION, SLOTTED OR PERFORATED
DISCHARGE PIPING, SPRAY
IRRIGATION, OR OTHER MEANS TO APPLY THE WATER OVER A LARGE AREA
AT LOW VELOCITY, IN SUCH
A MANNER AS TO CAUSE NO EROSION, REMOVAL OF TOPSOIL, OR
VIOLATION OF WATER QUALITY
STANDARDS IN THE RECEIVING WATERS.
CONTRACTOR SHALL ADD OR MOVE DISCHARGE COMPONENTS AS NEEDED TO
ENSURE NO OVERLAND
FLOW CAUSES SOIL EROSION, LEAVES THE PROJECT SITE, ENTERS THE
ADJACENT PROPERTIES OR
ROADWAYS, ENTERS THE ACTIVE CONSTRUCTION AREA, OR CAUSES A
VIOLATION OF WATER QUALITY
STANDARDS IN THE RECEIVING WATERS.
CONTRACTOR SHALL PROVIDE SUFFICIENT DISCHARGE TUBING, FILTER
BAGS, OR OTHER DISCHARGE
SYSTEMS TO POTENTIALLY APPLY WATER OVER AS MUCH AREA AVAILABLE
FOR DISCHARGE AS
NEEDED, IF REQUIRED, TO ALLOW SUFFICIENT INFILTRATION TO
MITIGATE EROSION ISSUES.
FILTER BAGS SHALL BE OF SUFFICIENT NUMBER, SIZE, AND CAPACITY TO
HANDLE ANTICIPATED FLOW
RATES, AND MUST BE INSPECTED, MAINTAINED, AND REPLACED WHEN FULL
OR DAMAGED. SLOTTED OR
PERFORATED DRAIN PIPE, IF USED, MUST BE DESIGNED TO DISCHARGE
ALONG THE ENTIRE LENGTH AT
EQUAL PRESSURES.
DISCHARGE TREATMENT
THE CONTRACTOR SHALL PROVIDE TREATMENT OF THE DISCHARGE
INCLUDING SUFFICIENT SEDIMENT
SETTLING CAPACITY (PONDS, STORAGE TANKS, ETC.) TO ENSURE
DISCHARGE DOES NOT EXCEED
TURBIDITY STANDARDS AT THE RECEIVING WATERS; AND 10 PPM
SUSPENDED SOLIDS (SILT, SILICA,
SEDIMENT ETC.) AS MEASURED USING A ROSSUM SAND TESTER
IMMEDIATELY PRIOR TO DISCHARGE TO
THE DESIGNATED DISCHARGE AREA.
THE DEWATERING DISCHARGE TREATMENT SYSTEM SHALL INCLUDE ANY
STORAGE TANKS, PLUMBING,
PUMPS, FILTRATION SYSTEMS, OTHER EQUIPMENT, APPURTENANCES, AND
RELATED WORK TO
PERFORM THE FUNCTION OF WATER TREATMENT.
DISCHARGE MONITORING
THE CONTRACTOR'S EROSION CONTROL SPECIALIST SHALL ANALYZE
DISCHARGE FOR TURBIDITY
HOURLY DURING THE FIRST FOUR HOURS OF TESTING, DAILY DURING
FIRST WEEK, WEEKLY
THEREAFTER, AND AFTER ANY RAINFALL EVENT EXCEEDING 0.25 INCHES
PER DAY, WITH A FIELD
TURBIDITY METER USING STANDARD METHOD 2130 (STANDARD METHODS FOR
THE EXAMINATION OF
WATER AND WASTEWATER). THE CONTRACTOR SHALL MEASURE TURBIDITY AT
ALL DISCHARGE POINTS
TO RECEIVING WATERS OR WETLANDS, AND BACKGROUND. TURBIDITY SHALL
BE CALCULATED AS THE
AVERAGE (MEAN) FOR ANY NUMBER OF SAMPLES. THE NUMBER AND TIMING
OF SAMPLES SHALL BE
THE SAME FOR EACH SAMPLING STATION (I.E., BACKGROUND AND
DISCHARGE POINTS). THE
CONTRACTOR SHALL PROVIDE ADDITIONAL TREATMENT PRIOR TO
DISCHARGE, AS NECESSARY, TO
MEET THE DISCHARGE LIMITS.
THE CONTRACTOR SHALL VISUALLY INSPECT THE DISCHARGE SYSTEM DAILY
FOR SYSTEM OPERATION,
OVERLAND FLOW, EROSION, AND TURBIDITY THROUGHOUT THE
TESTING.
THE CONTRACTOR SHALL SUBMIT WEEKLY MONITORING REPORTS TO THE
OWNER'S DESIGNATED
REPRESENTATIVE DOCUMENTING THE REQUIREMENTS HEREIN.
EROSION RISK ASSESSMENT
FACTORS ANTICIPATED TO CREATE RISK OF EROSION THROUGHOUT THE
PROJECT INCLUDE EXPOSURE OF EXCAVATED SOILS
TO RAINFALL AND DISTURBANCE OF THE PROJECT SITE BY HEAVY
EQUIPMENT. HEAVY RAINFALL CAN ERODE SOILS AND LEAD TO
TRANSPORT OF SEDIMENTS OVERLAND, THROUGH OPEN SEWER OR STORM
PIPES AS THEY ARE CONSTRUCTED, OR IN
DRAINAGE DITCHES. DEWATERING OF THE TRENCHES AND LIFT STATION
EXCAVATION WILL ALSO CREATE A RISK OF SEDIMENT
TRANSPORT, RELATIVE TO THE AMOUNT OF WATER THAT MUST BE REMOVED.
THE SOURCES OF WATER FOR DEWATERING
INCLUDE RAINFALL, STORMWATER FLOW, AND GROUNDWATER FLOW.
SWPPP TEMPORARY EROSION CONTROL NOTES
1. NON-COMPLIANCE WITH THE EROSION CONTROL REQUIREMENTS, WATER
QUALITY REQUIREMENTS AND CLEARING LIMITS
VIOLATIONS MAY RESULT IN A TEMPORARY STOP-WORK ORDER UNTIL SAID
EROSION CONTROL MEASURES ARE FUNCTIONAL.
2. CLEARING LIMITS SHALL BE ESTABLISHED FIRST THEN EROSION
CONTROL BEST MANAGEMENT PRACTICES (BMPS) SHALL BE
INSTALLED PRIOR TO ANY SITE DISTURBANCE. THE
EROSION/SEDIMENTATION CONTROL FACILITIES SHALL BE CONSTRUCTED
PRIOR TO ANY GRADING OR EXTENSIVE LAND CLEARING IN ACCORDANCE
WITH THE APPROVED CONSTRUCTION STORM
WATER POLLUTION PREVENTION PLAN (SWPPP). THESE FACILITIES MUST
BE SATISFACTORILY MAINTAINED UNTIL
CONSTRUCTION AND LANDSCAPING IS COMPLETED, THE PERMANENT
VEGETATIVE COVER IS ESTABLISHED AND THE
POTENTIAL FOR ON-SITE EROSION HAS PASSED.
3. PUBLIC STREETS ARE TO BE KEPT CLEAR OF DIRT AND DEBRIS DURING
CONSTRUCTION EXCAVATION AND FILL OPERATIONS.
MATERIAL SHALL BE REMOVED FROM THE STREETS BY SWEEPING. PAVED
SURFACES MUST BE CLEANED AT THE END OF
EACH DAY.
4. SEDIMENT CONTROL FACILITIES SHOWN ON THESE PLANS SHALL BE
INSTALLED AS PART OF THE PLAN TO REMOVE SEDIMENT
FROM THE WATER BEFORE CLEARING AND GRADING IS ALLOWED. THIS MAY
INCLUDE SEDIMENT PONDS, SILT FENCES,
SWALES, CHANNELS, BERMS, BARRIERS AND OTHER MEASURES. SEE THE
CONSTRUCTION SEQUENCE FOR ORDER OF
INSTALLATION.
5. EXCAVATED MATERIAL SHALL BE PLACED ON THE UPHILL SIDE OF
TRENCHES, UNLESS INCONSISTENT WITH SAFETY OR SITE
CONSTRAINTS.
6. THE CONSTRUCTION PLANS INDICATE INSTALLATION OF BEST
MANAGEMENT PRACTICES (BMPS) TO RETAIN ALL SEDIMENT ON
SITE. ADDITIONAL MEASURES ARE NORMALLY NEEDED TO REMOVE
TURBIDITY AND MEET WATER QUALITY STANDARDS.
DURING CONSTRUCTION, THE CONTRACTOR SHALL INSTALL SUCH
ADDITIONAL COUNTY APPROVED BMPS AS MAY BE
REQUIRED, E.G. BAKER TANKS OR OTHER SEDIMENTATION FACILITIES, TO
PREVENT SEDIMENT OR TURBID WATER FROM
LEAVING THE SITE. THE CONTRACTOR MAY CONTACT THE DESIGN ENGINEER
(OR THE OWNER'S DESIGNATED EROSION
CONTROL PERSON) FOR GUIDANCE ON ADDITIONAL MEASURES.
7. STABILIZE ALL EXPOSED AND NON-WORKED SOIL.
8. FROM MAY 1 TO SEPTEMBER 30 NO UN-WORKED SOIL MAY REMAIN
EXPOSED FOR MORE THAN 7 DAYS.
9. COVER DENUDED AREAS AS SPECIFIED ON THE PLANS BY APPROPRIATE
COVER BMPS (SUCH AS MULCH, SOD, AND STRAW).
WHERE STRAW MULCH IS REQUIRED, IT SHALL BE APPLIED A MINIMUM OF
2".
10. COVER MATERIAL SHALL BE STOCKPILED ON SITE.
11. SOIL STOCKPILES SHALL BE STABILIZED AND PROTECTED WITH
SEDIMENT RETENTION BMPS WITHIN 24 HOURS.
12. GRADING AND CONSTRUCTION SHALL BE TIMED AND CONSTRUCTED IN
STAGES TO MINIMIZE SOIL EXPOSURE.
CONSTRUCTION SHALL BE TIMED TO RECOGNIZE CONDITIONS CREATED BY
THE WEATHER.
13. FROM OCTOBER 1 TO APRIL 30 NO UN-WORKED SOIL MAY REMAIN
EXPOSED FOR MORE THAN 2 DAYS.
14. AN ESTABLISHED GROUND COVER THAT FULFILLS THE REQUIREMENT OF
THE APPROVED CONSTRUCTION PLANS IS
REQUIRED FOR ACCEPTANCE BY THE COUNTY WHERE POSSIBLE, MAINTAIN
NATURAL VEGETATION FOR SILT CONTROL.
a. ALL AREAS TO BE SEEDED SHALL BE CULTIVATED BY DISKING,
RAKING, HARROWING OR OTHER ACCEPTABLE MEANS.
b. PERFORM ALL CULTIVATING ACROSS OR AT RIGHT ANGLES TO THE
SLOPE.
c. COVER THE SITE WITH MULCH, TOPSOIL OR OTHER SOIL
AMENDMENTS.
d. IF NECESSARY, SURFACE RUNOFF CONTROL MEASURES SUCH AS
GRADIENT TERRACES, INTERCEPTOR DIKE/SWALES,
LEVEL SPREADERS, AND SEDIMENT BASINS SHALL BE INSTALLED PRIOR TO
SEEDING.
e. IMMEDIATELY FOLLOWING FINISH GRADING, PERMANENT VEGETATION
(CONSISTING OF RAPID, PERSISTENT AND
LEGUME) WILL BE APPLIED (MINIMUM 80# PER ACRE), UNLESS OTHERWISE
NOTED AS A WETLAND RESTORATION AREA
OR OTHERWISE APPROVED FOR ALTERNATIVE LANDSCAPING TREATMENT.
THIS IS TO INCLUDE THE FOLLOWING: 60%
3-WAY PERENNIAL RYE GRASS BLEND, 25% CHEWING FESCUE, 15%
CREEPING FESCUE. NO CLOVER OR NOXIOUS
WEEDS WILL BE PERMITTED.
f. FERTILIZER SHALL BE APPLIED AT 400# PER ACRE OF 10-20-20 (10
POUNDS PER 1100 SQUARE FEET) OR EQUIVALENT.
DEVELOPMENTS ADJACENT TO WATER BODIES SHALL USE NON-PHOSPHORUS
FERTILIZER.
15. UNLESS IN A WETLAND RESTORATION AREA OR AN AREA APPROVED FOR
ALTERNATIVE LANDSCAPING TREATMENT, ALL
DISTURBED AREAS SHALL BE SEEDED WITH A PERENNIAL GROUND COVER
USING AN APPROVED HYDROSEEDER OR AS
OTHERWISE APPROVED BY THE OWNER.
16. PROTECT CUT AND FILL SLOPES FROM EROSIVE FLOWS AND
CONCENTRATED FLOWS UNTIL PERMANENT COVER AND
DRAINAGE CONVEYANCE SYSTEMS ARE IN PLACE.
17. INSTALL INLET PROTECTION ON ALL STORM DRAIN INLETS DURING
CONSTRUCTION SO THAT SEDIMENT AND SILT LADEN
WATER IS FILTERED OR TREATED TO MINIMIZE SEDIMENT THAT ENTERS
THE INLET.
18. CHANNELS, DITCHES, SWALES AND OTHER CONVEYANCE SYSTEMS SHALL
BE STABILIZED TO PREVENT EROSION DURING AND
AFTER CONSTRUCTION. INSTALL OUTLET PROTECTION FOR ALL
CULVERTS.
19. FOLLOW THE SPECIFIC REQUIREMENTS ON THE PLAN TO CONTROL
POLLUTANTS DURING CONSTRUCTION. THE CONTRACTOR
AND OWNER SHALL DEVELOP ON GOING PLANS TO CONTROL POLLUTANTS
GENERATED DURING CONSTRUCTION, INCLUDING
WASTE MATERIALS AND DEMOLITION DEBRIS. THIS INCLUDES MAINTENANCE
OF CONSTRUCTION EQUIPMENT, FERTILIZERS,APPLICATION OF CHEMICALS,
AND WATER TREATMENT SYSTEMS. THE PLANS SHALL BE UPDATED TO RESPOND
TO SITE
EXPOSURE AND WEATHER CONDITIONS.
20. THE WATER FROM DE-WATERING SYSTEMS FOR TRENCHES, VAULTS AND
FOUNDATIONS SHALL BE DISCHARGED INTO A
CONTROLLED SYSTEM OR SEDIMENT RETENTION BMP (I.E. BAKER TANK).
ADDITIONAL MEASURES ARE NEEDED TO REMOVE
TURBIDITY AND MEET WATER QUALITY STANDARDS. UNFILTERED WATER
MUST NOT BE RELEASED INTO SENSITIVE AREAS
SUCH AS WETLANDS OR DESIGNATED NGPA AREAS.
21. THE OWNER AND CONTRACTOR ARE RESPONSIBLE FOR WATER QUALITY
AS FURTHER DEFINED IN THE PROJECT
SPECIFICATIONS. THE CONTRACTOR'S CERTIFIED EROSION CONTROL
SPECIALIST SHALL BE RESPONSIBLE FOR INSPECTION
AND THE WATER QUALITY MONITORING PROGRAM AND SHALL REPORT TO THE
OWNER AS REQUIRED.
22. THE CONSTRUCTION EROSION CONTROL BMPS SHALL BE INSPECTED
AFTER EACH SIGNIFICANT RAIN EVENT. MAINTENANCE
SHALL BE PERFORMED AS NEEDED TO MAINTAIN THE PERFORMANCE AND
FUNCTION.
a. SILT BARRIERS AND SEDIMENT PONDS (IF USED) SHALL BE INSPECTED
IMMEDIATELY AFTER EACH RAINFALL AND AT
LEAST DAILY DURING PROLONGED RAINFALL.
b. NECESSARY REPAIRS TO BARRIERS, CHANNELS, AND PONDS (IF USED)
OR REPLACEMENT SHALL BE ACCOMPLISHED
PROMPTLY.
c. SEDIMENT DEPOSITS SHOULD BE REMOVED AFTER EACH RAINFALL FROM
SILT BARRIERS AND CHECK DAMS.
d. WHEN THE SEDIMENT REACHES THE CLEAN OUT LEVEL IN A SEDIMENT
POND, IT SHALL BE REMOVED AND PROPERLY
DISPOSED. DEPOSITS MUST BE REMOVED WHEN THE LEVEL OF DEPOSITION
REACHES APPROXIMATELY ONE-THIRD
THE HEIGHT OF THE BARRIER, CHECK DAM OR OTHER CATCHMENT.
e. IF USED, THE EMBANKMENT OF SEDIMENT BASINS SHALL BE CHECKED
REGULARLY TO INSURE THAT IT IS
STRUCTURALLY SOUND AND HAS NOT BEEN DAMAGED BY EROSION OR
CONSTRUCTION EQUIPMENT.
f. THE EMERGENCY SPILLWAY OF A SEDIMENT POND SHALL BE CHECKED
REGULARLY TO INSURE THAT ITS LINING IS
WELL ESTABLISHED AND EROSION-RESISTANT.
g. ANY SEDIMENT DEPOSITS REMAINING IN PLACE AFTER THE BARRIER IS
NO LONGER REQUIRED SHALL BE DRESSED TO
CONFORM TO THE EXISTING GRADE, PREPARED AND SEEDED.
SWPPP EROSION CONTROL PLAN
(THIS PLAN MAY BE REVISED BY THE EROSION CONTROL SPECIALIST TO
MEET FIELD CONDITIONS, IF NECESSARY.)
1. EROSION PROBLEM AREAS
a. THERE ARE CURRENTLY NO KNOWN EROSION PROBLEM AREAS ON SITE.
HOWEVER, EROSION IS A POSSIBILITY DURING CONSTRUCTION. THE RISK
OF
EROSION IN THIS AREA MAY BE MITIGATED THROUGH THE USE OF PROPER
BEST MANAGEMENT PRACTICES AS DESCRIBED BELOW. SINCE RAINFALL ON
THE
SITE IS LIKELY TO BE A PRINCIPAL CAUSE OF EROSION, THE RISK OF
EROSION WILL BE REDUCED BY SCHEDULING EARTHWORK FOR THE DRY
SUMMER
SEASON.
b. IF THIS PROJECT CONTINUES INTO THE WINTER SEASON, THE
FOLLOWING WET WEATHER PRECAUTIONS WILL BE PRACTICED.
i. PREVENTION OF TRACKING MUD ONTO ROADS THROUGH THE USE OF
EQUIPMENT SWEEPING ONSITE.
ii. EXPOSED PORTIONS OF THE SITE SHALL BE ADEQUATELY COVERED BY
STRAW OR OTHER MATERIAL BASED UPON THE WEATHER. STRAW OR
APPROVED EQUIVALENT MATERIAL SHALL ALWAYS BE AVAILABLE ON SITE
AND READY TO USE. EXPOSED AREAS SHALL BE ADEQUATELY COVERED
WHEN RAINING AND AT THE END OF THE DAY IF THE NEXT DAY IS A
"NON-WORKING" DAY. WEATHER FORECASTS SHALL BE USED TO GOVERN
WHETHER WORK WILL COMMENCE OR STOP FOR THE DAY.
iii. ALL SITE WORK GENERATING EXPOSED SOIL (WITH THE EXCEPTION
OF INSTALLATION AND MAINTENANCE OF EROSION CONTROL BMPS) SHALL
CEASE
DURING WEATHER CONDITIONS WHEN RAIN GENERATES RUNOFF AND CAUSES
EROSION.
iv. IF NECESSARY, EARTHWORK SHALL BE PHASED TO MINIMIZE AREAS OF
EXPOSED SOIL.
v. THE CONTRACTOR SHALL DEVISE A MAINTENANCE AND INSPECTION
SCHEDULE WITH AN IDENTIFIED EROSION CONTROL SPECIALIST
RESPONSIBLE
FOR THESE ITEMS.
vi. AN EROSION CONTROL SPECIALIST SHALL BE PRESENT OR ON-CALL
THROUGHOUT THE PROJECT DURATION TO INSURE THE BMPS ARE WORKING
APPROPRIATELY AND ARE WELL MAINTAINED. THE SPECIALIST SHALL
MONITOR THE DISCHARGE FROM THIS SITE AFTER EACH STORM EVENT
THAT
GENERATES RUNOFF. THEY SHALL ALSO CONDUCT SITE INSPECTION
REPORTS ON THE INSTALLED BMPS. THESE REPORTS SHALL BE AVAILABLE
ON
SITE AND PROVIDED TO THE OWNER ON A MONTHLY BASIS AND WHEN
REQUESTED. THE MONITORING SHALL BE DONE IN A PROFESSIONAL
MANNER
CONSISTENT WITH CURRENT SAMPLING PROTOCOLS AND REPORTING
REQUIREMENTS.
vii. VEGETATED BUFFERS AND CRITICAL AREAS SHALL BE PROTECTED,
ESPECIALLY THROUGH THE USE OF SILT FENCES AND MINIMIZATION OF
SOIL
EXPOSURE.
viii. IF NECESSARY, WATER FROM THE PROJECT SITE SHALL BE
FILTERED THROUGH AN APPROVED DEVICE SUCH AS A BAKER TANK, PRIOR TO
RELEASING
IT TO THE VEGETATED WETLAND AREA. THE CONTRACTOR SHALL
CREATE/MODIFY THE DEWATERING PLAN BASED UPON SITE CONDITIONS AND
SHALL
ATTACH IT TO THIS STORMWATER POLLUTION PREVENTION PLAN
(SWPPP).
2. CONSTRUCTION STORMWATER POLLUTION PREVENTION PLAN
ELEMENTS
a. MARK CLEARING LIMITS (BMP C103 - HIGH VISIBILITY PLASTIC)
CLEARING LIMITS ARE SHOWN ONTHE PLANS.
b. ESTABLISH CONSTRUCTION ACCESS (BMP C105 - STABILIZED
CONSTRUCTION ENTRANCE)
CONSTRUCTION ACCESS WILL BE THE PAVED DRIVEWAY FROM MUKILTEO
SPEEDWAY. AS A PROTECTIVE MEASURE, STREET SWEEPING WILL BE
PERFORMED WHEN REQUIRED.
c. CONTROL FLOW RATES (BMP C200 - INTERCEPTOR SWALE; BMP C206 -
LEVEL SPREADER)
MINOR ADDITIONAL FLOW IS EXPECTED FROM THIS PROJECT FLOW WILL BE
CONTROLLED WITH APPROPRIATE BMPS AS NEEDED SUCH AS WITH CHECK
DAMS (BMP C207) OR STRAW WATTLES (BMP C235) IF REQUIRED.
d. INSTALL SEDIMENT CONTROLS (BMP C233 - SILT FENCE)
SEDIMENT CONTROLS INCLUDE A SILT FENCE ALONG THE PERIMETER OF
THE SITE, COVERING OF SOIL STOCKPILES, AND INSTALLATION OF STRAW
WHEN
NECESSARY. EROSION CONTROL BMPS SHALL BE INSTALLED PRIOR TO LAND
DISTURBING ACTIVITIES AS NOTED ON THE PLANS. THE SITE SHALL ALSO
BE
MONITORED AND TESTED SO THAT TURBIDITY IN THE WATER LEAVING THE
AREA WILL NOT EXCEED 5 NTU ABOVE BACKGROUND.
e. STABILIZE SOILS (BMP C122 - NETS AND BLANKETS; BMP C123 -
PLASTIC COVERING)
TO PROTECT THE SOIL STOCKPILES FROM EROSIVE FORCES SUCH AS RAIN,
PLASTIC SHEETING, JUTE MATS OR SIMILAR BMPS WILL BE PLACED UPON
EXPOSED AND NON-WORKED SOIL THROUGHOUT CONSTRUCTION. PER WET
WEATHER REQUIREMENTS, THESE BMPS WILL BE PLACED WITHIN 2 DAYS
OF
STOCKPILING THE SOIL FROM OCTOBER 1ST THROUGH APRIL 30TH OR IF
RAINING. DUST CONTROL PER BMP C140 SHALL BE IMPLEMENTED AS
WELL.
f. PROTECT SLOPES (BMP C122 - NETS AND BLANKETS)
ANY SLOPES ALONG THE PROJECT SITE SHALL NOT BE DAMAGED FROM
CONCENTRATED FLOWS. STOCKPILE SLOPES SHALL BE PROTECTED AS
MENTIONED IN THE "STABILIZE SOILS" SECTION.
g. PROTECT DRAIN INLETS (BMP C220 - STORM DRAIN INLET
PROTECTION)
TO PREVENT SEDIMENT FROM MOVING INTO ANY NEARBY STORM SYSTEM,
CATCH BASIN INLET PROTECTION SHALL BE USED FOR CATCH BASINS
ENCOUNTERED ALONG THE PROJECT. INLETS WILL BE INSPECTED WEEKLY
AT A MINIMUM AND DAILY DURING STORM EVENTS AS NOTED ON THE
PLANS.
SEDIMENT SHALL NOT ACCUMULATE GREATER THAN SIX INCHES IN DEPTH
WITHIN THE INLET PROTECTION DEVICE.
h. STABILIZE CHANNELS AND OUTLETS (BMP C209 - OUTLET
PROTECTION)
SHOULD IT BE NECESSARY, CHECK DAMS PER BMP C207 MAY BE USED
TOHELP STABILIZE CHANNELS THROUGHOUT THE DURATION OF THE
PROJECT.
i. CONTROL POLLUTANTS (BMP C233 - SILT FENCE)
GOOD HOUSEKEEPING PRACTICES AND APPROPRIATE BMPS AS SHOWN ON THE
PLANS AND APPROVED BY THE GOVERNING JURISDICTION WILL BE
UTILIZED TO CONTROL POLLUTANTS ON THE SITE. TO ENSURE THIS, A
NOTE IS STATED ON THE PLANS REQUIRING ALL POLLUTANTS ON SITE TO
BE
HANDLED AND DISPOSED OF IN A MANNER THAT DOES NOT CAUSE
CONTAMINATION OF SURFACE WATER. ANY WATER THAT IS USED TO CLEAN
EQUIPMENT OR IS PUMPED FROM THE EXISTING DRAINAGE FACILITIES
SHALL BE FILTERED THROUGH AN APPROVED FILTERING DEVICE AND
TESTED
PRIOR TO DISCHARGING TO AN UNDEVELOPED PORTION OF THE SITE
SAWCUTTING ACTIVITIES SHALL FOLLOW BMP C152.
j. CONTROL DEWATERING (BMP C251 - CONSTRUCTION STORMWATER
FILTRATION)
ANY WATER FROM DEWATERING OPERATIONS THAT MAY OCCUR THROUGHOUT
THIS PROJECT WILL BE CONVEYED TO AN APPROVED FILTER SUCH AS A
BAKER TANK AND THEN RELEASED TO AND UNDISTURBED AREA ON SITE.
ALL MEASURES SHALL COMPLY WITH REGULATION STANDARDS. THE
CONTRACTOR SHALL CREATE A DEWATERING PLAN BASED UPON SITE
CONDITIONS AND SHALL ATTACH IT TO THIS STORMWATER POLLUTION
PREVENTION
PLAN (SWPPP).
k. MAINTAIN BMPS
THE BMPS SHOWN ON THE PLANS SHALL BE MAINTAINED AND REPAIRED AS
NEEDED. SPECIFIC MAINTENANCE REQUIREMENTS ARE LISTED IN THE
NOTES
AND/OR DETAILS ON THE PLANS. MONITORING SHALL BE CONDUCTED BY
THE DESIGNATED EROSION CONTROL SPECIALIST TO INSURE BMPS ARE
WORKING EFFECTIVELY AND ARE NOT DAMAGING FACILITIES OR WATERWAYS
DOWNSTREAM OF THE SITE. A NOTE HAS BEEN ADDED TO THE PLANS
STATING THAT TRAPPED SEDIMENT SHALL BE REMOVED OR STABILIZED ON
THE SITE UPON COMPLETION OF THE WORK AS APPROPRIATE MATERIALS
SHALL BE ON HAND PER BMP C150 IN ORDER TO PROVIDE MAINTENANCE OR
EMERGENCY MEASURES RELATED TO EROSION CONTROL.
l. MANAGE THE PROJECT
EROSION CONTROL SPECIALIST: THE CONTRACTOR SHALL PROVIDE THE
NAME OF A CERTIFIED EROSION CONTROL SPECIALIST (PER BMP C160)
THAT
WILL VERIFY THE ACTIONS NOTED IN THIS STORMWATER POLLUTION
PREVENTION PLAN AND ON THE DRAWINGS WILL BE IMPLEMENTED.
PHASING OF CONSTRUCTION): PHASING OF THE WORK SHALL COMPLY WITH
BMP C162 (SCHEDULING). THE FIRST ORDER OF WORK WILL INCLUDE
INSTALLING APPROPRIATE BMPS FOR EROSION CONTROL. PROJECT
DEVELOPMENT WILL THEN COMMENCE. THE SITE SHALL BE PROTECTED AS
DESCRIBED IN THIS PLAN AND ON THE DRAWINGS. THROUGHOUT THE WORK,
THE CONTRACTOR IS RESPONSIBLE FOR MAINTAINING ALL BMPS. UPON
COMPLETION OF THE WORK, TEMPORARY BMPS SHALL BE REMOVED AS
NECESSARY.
SEASONAL WORK LIMITATIONS: WORK IS SCHEDULED FOR THE DRY SEASON
HOWEVER, IT MAY BE CONDUCTED DURING THE WET WEATHER SEASON OF
OCTOBER 1 THROUGH MARCH 31ST. ALL STOCKPILES SHALL BE COVERED
WITH PLASTIC SHEETING, STRAW (OR EQUAL) TO MINIMIZE ANY LOSS OF
SOIL
DURING THE WET WEATHER. THE CONTRACTOR WILL BE RESPONSIBLE FOR
CONSISTENTLY MONITORING THE OUTFALLS TO ENSURE ALL APPLICABLE
REQUIREMENTS ARE MET AND THAT WATER QUALITY DOWNSTREAM IS NOT
BEING COMPROMISED THROUGHOUT THIS PROCESS. IN ADDITION, THE
CONTRACTOR'S CERTIFIED EROSION CONTROL SPECIALIST WILL BE
RESPONSIBLE FOR ENSURING PROPER BMP MAINTENANCE IS CONDUCTED
THROUGHOUT THE SEASON AS WELL AS ENSURING THE LOCAL
JURISDICTION'S REQUIREMENTS ARE MET THROUGH TESTING AND OTHER
APPROPRIATE
METHODS.
COORDINATION WITH UTILITIES AND OTHER CONTRACTORS: AS STATED ON
THE PLANS AND IN THE SPECIFICATIONS, THE CONTRACTOR SHALL BE
RESPONSIBLE FOR COORDINATING ANY UTILITY WORK WITH THE
APPROPRIATE AGENCIES.
INSPECTION AND MONITORING: THE CONTRACTOR'S EROSION CONTROL
SPECIALIST SHALL BE PRESENT OR ON-CALL THROUGHOUT THE PROJECT
DURATION TO INSURE THE BMPS ARE WORKING APPROPRIATELY AND ARE
WELL MAINTAINED. THE SPECIALIST SHALL CHOOSE APPROPRIATE
MONITORING
SITES AND NOTE THEM ON BOTH THE GROUND AND ON THE FIELD COPY OF
THE PLANS. THE SPECIALIST SHALL MONITOR THE DISCHARGE FROM THIS
SITE AFTER EACH STORM EVENT THAT GENERATES RUNOFF. THE
SPECIALIST SHALL ALSO CONDUCT SITE INSPECTION REPORTS ON THE
INSTALLED
BMPS. THE MONITORING SHALL BE DONE IN A PROFESSIONAL MANNER
CONSISTENT WITH CURRENT SAMPLING PROTOCOLS AND REPORTING
REQUIREMENTS.
REPORTING: A NOTE HAS BEEN ADDED TO THE PLANS STATING THAT THE
CONTRACTOR IS RESPONSIBLE FOR REPORTING ALL SPILLS OR DISCHARGE
OF
POLLUTANTS WITHIN 24-HOURS TO THE OWNER. THE SITE INSPECTION
REPORTS MENTIONED ABOVE WILL BE AVAILABLE ON SITE AND PROVIDED TO
THE
OWNER ON A MONTHLY BASIS OR WHEN REQUESTED.
MAINTENANCE : NO MAINTENANCE ON HEAVY EQUIPMENT IS EXPECTED TO
OCCUR ON SITE THROUGHOUT THE PROJECT.
MAINTENANCE OF THE CONSTRUCTION SWPPP: THIS PLAN WILL BE LOCATED
ON SITE AT ALL TIMES. THE PLAN WILL BE REVISED ACCORDINGLY IF
SIGNIFICANT CHANGES HAVE BEEN MADE TO THE DESIGN, CONSTRUCTION,
OPERATION, OR MAINTENANCE OF ANY BMPS.
l. PROTECT LOW IMPACT DEVELOPMENT FACILITIES
NO LOW IMPACT DEVELOPMENT FACILITIES ARE INTENDED FOR THIS
SITE.
SW
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