WATER QUALITY PROTECTION AND MONITORING PLAN PORT OF VANCOUVER, USA TERMINAL 5 BULK POTASH HANDLING FACILITY

Transcription

1 WATER QUALITY PROTECTION AND MONITORING PLAN PORT OF VANCOUVER, USA TERMINAL 5 BULK POTASH HANDLING FACILITY Prepared for Port of Vancouver, USA BHP Billiton Canada, Inc. Prepared by Anchor QEA, LLC 6650 SW Redwood Lane, Suite 333 Portland, OR October 2011

2 WATER QUALITY PROTECTION AND MONITORING PLAN PORT OF VANCOUVER USA TERMINAL 5 BULK POTASH HANDLING FACILITY Prepared for Port of Vancouver, USA BHP Billiton Canada Inc. Prepared by Anchor QEA, LLC 6650 SW Redwood Lane, Suite 333 Portland, OR October 2011

3 TABLE OF CONTENTS 1 INTRODUCTION Project Description Water Quality Criteria WATER QUALITY PROTECTION MEASURES General Water Quality Protection Measures Stormwater Outfall Replacement Pile Installation in Riprap Armor Pile Removal General Over-water Construction Work General Concrete Work Nearshore Stone Column Installation WATER QUALITY MONITORING PLAN Visual Monitoring Monitoring Parameters Monitoring Schedule Monitoring Locations Instrumented Monitoring Monitoring Parameters Monitoring Schedule Monitoring Locations Monitoring Depths Record Keeping CONTINGENCY RESPONSE AND NOTIFICATION PLAN Contingency Measures Visible Turbidity Plume Instrument Field Monitoring Construction Debris in Water Distressed or Dying Fish Discharge of Oil, Fuel, or Chemicals Notification...18 Water Quality Protection and Monitoring Plan i

4 5 REFERENCES List of Tables Table 1 Water Quality Standards for Class A Water... 3 List of Figures Figure 1 Vicinity Map Figure 2 Monitored Construction Activities Water Quality Protection and Monitoring Plan ii

5 LIST OF ACRONYMS AND ABBREVIATIONS BHP Billiton BMP CRD Ecology MTPA NOAA NPDES NGVD NTU OHWM Port Q2 RM WAC WQPMP BHP Billiton Canada Inc or an affiliate of the BHP Billiton Group best management practice Columbia River Datum Washington State Department of Ecology million tonnes per annum National Oceanic and Atmospheric Administration National Pollutant Discharge Elimination System National Geodetic Vertical Datum Nephelometric Turbidity Unit Ordinary High Water Mark Port of Vancouver second quarter river mile Washington Administrative Code Water Quality Protection and Monitoring Plan Water Quality Protection and Monitoring Plan iii

6 1 INTRODUCTION This document presents the Water Quality Protection and Monitoring Plan (WQPMP) for construction activities associated with the Terminal 5 Bulk Potash Handling Facility at the Port of Vancouver, USA (Port). The site is located at 5701 Northwest Lower River Road in Vancouver, Washington, on the north bank of the Columbia River at approximately River Mile (RM) 103. The objective of the WQPMP is to monitor and control releases of turbidity, suspended sediment, concrete, and other construction-related materials that may be generated during the removal or filling of material in, over, or near the water, and to ensure compliance with Section 401 of the Clean Water Act, for which Ecology is the delegated regulatory authority, and the Washington State Surface Water Quality Standards ( A Washington Administrative Code [WAC]). In addition, earthwork performed on the shoreline of the site will be conducted in accordance with the terms and conditions of the Environmental Restrictive Covenant entered March 26, 2009, or any successor covenant that restricts this work. This document describes water quality protection measures; monitoring parameters, methods, and evaluation criteria; and contingency response and notification procedures in the event a water quality criterion is exceeded during construction activities. 1.1 Project Description BHP Billiton Canada, Inc., or an affiliate of the BHP Billiton Group (BHP Billiton), is proposing to lease part of Terminal 5 located at the Port for the purpose of establishing a bulk handling export facility to allow shipping of approximately 8 million tonnes per annum (MTPA) of potash to global markets (Figure 1). The facility will accept potash shipped by rail from potash mines located in Saskatchewan, Canada. On-site infrastructure is proposed to enable the unloading of rail cars into on-site storage, and the conveyance of potash to vessels at a new berth to be constructed on the Columbia River adjacent to the facility. The berth will contain a dual-quadrant shiploader system to receive and service various classes of cargo vessels, including Panamax Class vessels. The berth is anticipated to consist of shiploaders, support beams and pivot supports, berthing dolphins, mooring dolphins, a central maintenance trestle, and a berth structure (Figure 2). Other on-site infrastructure components will include a dedicated rail track for BHP Billiton, materials handling equipment, storage structures, utilities, on-site access roads, and related ancillary infrastructure. Water Quality Protection and Monitoring Plan

7 Introduction This WQPMP concerns work conducted below the ordinary high water mark (OHWM) under the jurisdiction of Section 401 of the Clean Water Act. The OHWM is defined as feet Columbia River Datum (CRD) (+16.7 feet National Geodetic Vertical Datum [NGVD] 29) in this reach of the Columbia River. Work performed above the OHWM will be regulated by the project s National Pollutant Discharge Elimination System (NPDES) construction stormwater permit, which will be secured under a separate permitting action. The following construction activities may involve removal or filling of material below the OHWM, and are the focus of this WQPMP: Construction of a replacement stormwater outfall on the bank of the terminal Installation of piles to support the new shiploader structure Removal of piles for habitat mitigation at the project site as well as at Terminal 2 General over-water work associated with construction of the shiploader structure General over-water or in-water concrete work, potentially including concrete filling of steel piles and casting of concrete pile caps and decking Installation of stone columns in nearshore areas for ground stabilization While not all of these activities include removal or filling of material below OHWM, as regulated under Section 401 of the Clean Water Act, they are included for completeness and to ensure State water quality standards are met during all construction work over or near the water as well as in the water. The location of these construction activities is shown on Figure 2. The activities are described further in Section Water Quality Criteria The Columbia River at the Port of Vancouver is designated as a Class A water body by the State of Washington ( A WAC). Characteristic uses include commerce and navigation, recreation, and support of aquatic life (including salmonids) and wildlife habitat. In consideration of the site construction activities (general earthwork and concrete work), turbidity and ph are the primary water quality parameters of concern. Table 1 presents the water quality standards for Class A water for turbidity and ph. Water Quality Protection and Monitoring Plan

8 Introduction Table 1 Water Quality Standards for Class A Water Monitoring Parameter Turbidity If less than 50 NTU: If greater than 50 NTU: Water Quality Criterion Background Turbidity plus 5 NTU Background Turbidity plus 10 percent ph ph shall be within the range of 6.5 to 8.5 with a human caused variation within the above range of less than 0.5 unit. Note: NTU = Nephelometric Turbidity Unit The water quality standards in Table 1 will need to be met at the compliance boundary at the edge of an authorized mixing zone. The mixing zone boundary is assumed to extend 300 feet (91.4 meters) downstream from the point of construction, as specified in WAC A- 100(7)(i), or as otherwise authorized in the Water Quality Certification for this project. The critical monitoring location will typically be directly downstream (i.e., west-northwest) from the point of construction, although tidal reversals are possible during flood tide conditions, which could shift the critical location upstream. In addition to the numerical criteria in Table 1, the project must also comply with narrative water quality standards, including the following: No visible petroleum sheen on water observed at the construction site No distressed or dying fish observed at the construction site and attributed to site activities Unlike the numerical criteria in Table 1, these narrative criteria are not subject to a mixing zone and therefore must be met immediately adjacent to the construction activity with no allowance for dilution. Water Quality Protection and Monitoring Plan

9 2 WATER QUALITY PROTECTION MEASURES This section describes the construction activities covered by this WQPMP and the protection measures or best management practices (BMPs) that will be implemented to minimize impacts to water quality. In addition to implementing the protection measures described in this WQPMP, water quality monitoring will also be performed during construction to ensure that the protection measures are effective, as described in Section 3. General and activityspecific water quality protection measures are described below. 2.1 General Water Quality Protection Measures Water quality protection measures that will be generally implemented on a project-wide basis during all work in or near the water include the following: All in-water work performed in the wet will be completed within the designated in-water work window to protect sensitive fisheries and aquatic resources. The inwater work window is between November 1 and February 28 or as otherwise authorized in project permits. Other work elements may be performed in the dry and will be completely removed or isolated from direct contact with the river; such activities are therefore proposed to be conducted outside the designated in-water work window. All equipment will be maintained in good proper running order to prevent leaking or spilling of potentially hazardous or toxic substances, including but not limited to hydraulic fluid, diesel, gasoline and other petroleum products. Equipment used in or over the water will use biodegradable hydraulic fluids to the extent practicable. Storage of fuels and petroleum products will comply with safe operating procedures, including containment facilities in case of a spill. Pile cut-offs, waste or any miscellaneous unused materials will be recovered for either disposal in a designated facility or placed in storage. No material will enter the Columbia River. Contractors will have emergency spill equipment available whenever working in or near the water. Contractors will position their water borne equipment in a manner that will minimize damage to existing habitat. Water Quality Protection and Monitoring Plan

10 Water Quality Protection Measures 2.2 Stormwater Outfall Replacement Description. The Port s stormwater outfall servicing Terminal 5 will be upgraded and relocated approximately 150 feet downstream from its current location (Figure 2). The new 36- to 60-inch diameter (91- to 152-cm diameter) stormwater pipe will be trenched into the subsurface through the shoreline berm and will daylight at approximately +10 feet NGVD29. The lower portion of the outfall, including the portion exposed above the river bed, will be supported on pile and beam structures similar to the existing outfall. Beneath the outfall, a splash pad consisting of a 2-foot-thick (0.61-meter) layer of riprap will be placed between approximately -5 feet and +5 feet NGVD29 to provide energy dissipation. The splash pad will be approximately 40 feet (12.2 meters) in diameter. The existing outfall will be abandoned by cutting the supporting timber piles below the mudline, cutting and capping the outfall pipe just above the mudline, and filling the pipe with grout. The Port is also evaluating an option to replace and/or rehabilitate the stormwater outfall at its current location which would further minimize construction impacts to the shoreline area. Invasive earthwork will be necessary to lay the new pipe in a trench through the shoreline berm and to remove sediment beneath the riprap apron in order to balance cut and fill and restore existing contours. The shoreline earthwork above the OHWM will be conducted in accordance with the terms and conditions of the Environmental Restrictive Covenant entered March 26, 2009, or any successor covenant that restricts this work. The earthwork necessary to build the subsurface pipe trench through the berm is planned to be completed in the dry during the seasonal low water level (September and October 2012) and before the in-water work window. Pile installation, excavation and placement of the splash pad, securing of the pipe to the support piles, and abandonment of the existing outfall will occur during the in-water work window (November 1, 2012 through February 28, 2013). A sheet pile coffer dam or equivalent may be installed to allow excavation of the splash pad in the dry; alternatively, the excavation of the splash pad may proceed carefully in the wet in conjunction with more rigorous water quality monitoring requirements (see Section 3). If a coffer dam is installed, the area behind the dam would be dewatered, and the dewatering water would be clarified in an upland settling basin or through an in-line filter before being returned to the river. Water Quality Protection and Monitoring Plan

11 Water Quality Protection Measures Water Quality Protection Measures. The following BMPs will be implemented to protect water quality during construction of the upgraded stormwater outfall: Trenching of the outfall pipe through the shoreline berm will be conducted entirely in the dry during seasonal low water. In addition, the following temporary erosion and sediment control measures will be implemented during trenching activities: Vertical shoring will be used in the trench to minimize the footprint of the trench, as well as the temporary stockpile volumes. Perimeter controls (i.e., straw wattles and/or silt fencing), stockpile covers, and gravel construction entrances will be employed. Because the outfall will daylight in an area of heavy riprap armor, it is not expected that slope stabilization measures will be necessary on the river bank. A coffer dam may be used to allow excavation of the splash pad foundation in the dry. Dewatering water behind the coffer dam would be clarified in an upland settling basin or through an in-line filter before discharging back to the river. Alternatively, excavation of the splash pad foundation may be performed in the wet. If this option is selected, instrumented turbidity monitoring would be required during excavation as described in Section 3. In addition, operational BMPs would be employed to minimize turbidity at the excavation site, including the following: Bottom or beach stockpiling of sediment will be prohibited. Overfilling of the excavator bucket shall be avoided. If necessary, the excavator bucket will be paused at the bottom before hoisting it through the water column. If necessary, the ascent velocity will be reduced as the loaded bucket is raised through the water column. In general, careful operational controls, such as those listed above, are expected to provide more effective turbidity control than a silt curtain, especially in a tidally influenced river environment. 2.3 Pile Installation in Riprap Armor Description. Approximately 100 concrete-filled steel piles will be installed below OHWM to support the new shiploader structure and the associated mooring and berthing dolphins. A Water Quality Protection and Monitoring Plan

12 Water Quality Protection Measures large majority of these piles will be placed in unobstructed deep water locations using standard vibratory methods to the extent possible, augmented by impact methods where necessary. However, a small number of piles (approximately 5) will be installed in shallower bank areas armored with riprap; in particular, to support the East Pivot structure (Figure 2). To allow pile installation, the existing riprap will be pulled aside, either manually or with the assistance of a small backhoe. It will then be replaced to original contours after the piles are installed. Pile installation at the East Pivot structure will occur between September 2012 and June 2013; the work will be conducted in the dry and therefore will not be constrained by the in-water work window. Water Quality Protection Measures. The following BMPs will be implemented during temporary riprap removal and replacement to facilitate pile installation on the upper bank: Work will be isolated from the river and conducted entirely in the dry. Because the piles will be installed in an area of heavy riprap armor, it is not expected that slope stabilization measures will be necessary on the river bank. 2.4 Pile Removal Description. Pile removal will be conducted at the project site as well as the Port s Terminal 2 as a part of the habitat mitigation requirements for the project. Piles will be removed using vibratory extraction or by pulling them with a crane mounted on a barge. If a pile is unable to be completely removed using vibratory or pulling methods, the pile will be cut off at or below the mudline using a pneumatic underwater chainsaw or pushed into the sediment. Water Quality Protection Measures. The following BMPs will be implemented during pile removal: When creosote-treated piles are being removed, a containment boom will surround the work area to contain and collect any floating debris and sheen. Any debris will be retrieved and properly disposed. The piles will be dislodged with a vibratory hammer, when possible, and will not be intentionally broken by twisting or bending. If a pile breaks above the mudline, it will be cut off at or below the mudline or pushed into the sediment. The piles will be removed in a single, slow, and continuous motion so as to minimize Water Quality Protection and Monitoring Plan

13 Water Quality Protection Measures sediment disturbance and turbidity in the water column. Removed piles, stubs, and associated sediment (if any) will be contained on a barge. The barge scuppers and any unprotected perimeter areas will be controlled using hay bales covered with filter fabric. All creosote-treated material, pile stubs, and associated sediments (if any) will be disposed of in a landfill approved to accept these types of materials. 2.5 General Over water Construction Work Description. Construction of the shiploader structure will likely require over-water welding, cutting, and other general over-water construction work. The over-water work associated with construction of the shiploader pivots, beams, trestles, walkways, and berthing structures is projected to occur between the second quarter (Q2) of 2013 and Q Because this work will occur out of the river, it will not be constrained by the in-water work window. Water Quality Protection Measures. The following BMPs will be implemented to minimize effects to water quality during over-water construction work: The contractor s Spill Prevention, Control, and Countermeasures Plan for marine operations will be implemented. All construction equipment will be clean and inspected daily before use to ensure that the equipment has no fluid leaks. Should a leak develop during use, the leaking equipment shall be removed from the project site immediately and will not be used again until it has been adequately repaired. At no time will fuels or oils be allowed to enter the river. Debris booms will be placed around the work areas to contain any materials or litter that may inadvertently drop into the water. Any materials dropped into the water would immediately be picked up by the contractor. 2.6 General Concrete Work Description. The existing outfall will be abandoned by cutting it back to the bank, capping the end, and filling the remaining section with grout. This is projected to occur in January through February Water Quality Protection and Monitoring Plan

14 Water Quality Protection Measures Approximately 100 piles will be installed to support the shiploader structure (pivots, beams, trestles, walkways) and associated mooring and berthing dolphins. Depending on the results of ongoing structural design work, some or all of these piles may be filled with concrete. Pile installation below the water line will occur during the in-water work window between November 2012 and February After the piles are installed, the over-water elements of the shiploader structure will be built. Concrete components of the shiploader include pile caps and trestle decking; these may be installed as pre-cast components, or cast in place. This work will generally occur between Q and Q Water Quality Protection Measures. During concrete and grout work in, over, or near the water, the following BMPs will be implemented: Wet concrete will be isolated from contact with surface water. Water-tight forms will be used to prevent leakage. Curing concrete will not be watered. Forms will be kept in place until curing is completed. Grouting of the abandoned outfall will be performed entirely in the dry ; a spill control basin may be placed below the abandoned outfall during grouting for secondary containment of any leakage. Once piles are driven to refusal and cutoff at their design elevation, the water inside will be pumped out. This water should be clean of oil and debris; however, the water will be pumped to a tank and visually inspected prior to release back to the river. Concrete will be injected into the piles from the bottom up; however, some water or infiltrate is expected in the piles and will rise with, and on top of the concrete. This contaminated water will be collected using a universal close-fitting tubular collar fabricated specifically for this project. A 6- to 10-foot apron will be welded around the exterior circumference of the pile for limited secondary containment prior to concrete injection. As the water rises to the top, it will drain through a port in the sidewall (located approximately one foot from the top of the collar), then into a tank on a barge for offsite disposal. The entire operation will be carefully and continuously monitored in order to prevent overfill and release of any contaminated water to the Columbia River. Water Quality Protection and Monitoring Plan

15 Water Quality Protection Measures 2.7 Nearshore Stone Column Installation Description. To improve the seismic stability of the terminal area, ground improvement work will be performed by installing stone columns in potential liquefaction areas. In particular, a field of approximately 1,900 stone columns are proposed in the nearshore area behind the shiploader structure, as shown on Figure 2. Stone columns are a ground improvement technique that combines soil densification and partial replacement of unstable material with crushed rock. The operation involves injecting and compacting aggregate at the base of a vibrating steel probe with the aid of compressed air. Stone column installation is planned to occur between Q through Q Based on WSDOT s recent experience with stone column installation projects, the subsurface ground vibration and injection of high-pressure air may percolate into open-water areas up to 75 feet (22.9 meters) away from the activity (Ecology 2010), potentially causing resuspension of sediment and organic matter and increased turbidity. The nearshore field of stone columns behind the shiploader structure ranges from 30 to 190 feet (9.1 to 57.9 meters) inland from OHWM, and is about 30 to 40 feet (9.1 to 12.2 meters) farther from the river during seasonal low water conditions. The stone columns in the southeast (upstream) quadrant of this ground improvement area are closest to the water and therefore most susceptible to turbidity generation. It should be noted that stone columns are also proposed to help stabilize the ground behind the Railcar Dumper Building and beneath the Storage Building, but these ground improvement areas are several hundred feet from the river and well beyond the range of potential impacts. Water Quality Protection Measures. Proposed water quality protection measures are consistent with the recommendations in Ecology s Guidance on Controlling Turbidity in Nearby Waters from Ground Improvement Work for Seismic Events (Ecology 2010). During nearshore stone column installation, the following BMPs will be implemented: Air injection methods will be used rather than water injection methods to minimize the potential for turbidity impacts. Visual monitoring of adjacent shoreline areas will be conducted during stone column installation within 75 feet of the river. If a turbidity plume is observed in the river as a result of ground improvement work on the adjacent uplands, instrumented Water Quality Protection and Monitoring Plan

16 Water Quality Protection Measures monitoring will be initiated to better quantify turbidity impacts at the compliance boundary (see Section 3.2). As necessary, other approved operational or engineering control measures would be implemented. Water Quality Protection and Monitoring Plan

17 3 WATER QUALITY MONITORING PLAN The primary monitoring method proposed for this project is visual monitoring, supported as necessary with contingent real-time instrumented monitoring of water quality parameters using a hydroprobe with ph and turbidity sensors. To the extent the construction work can be fully removed or isolated from the water and completed in the dry, visual monitoring will be performed. Instrumented monitoring will be performed if in-water earthwork is necessary; for example, if the foundation for the splash pad of the replacement outfall is excavated in the water and without use of a coffer dam. Instrumented monitoring may also be implemented if a significant turbidity plume is observed during visual monitoring, to better assess compliance with water quality standards and the effectiveness of any supplemental BMPs that may be implemented to control turbidity. In the event that an exceedance of water quality standards is indicated by either visual or instrumented monitoring, contingency response actions and agency notifications will be triggered. The contingency response and notification plan is provided in Section Visual Monitoring Visual monitoring will be performed during all construction activities that are removed or isolated from the water or performed in the dry. Specifically, visual monitoring will be performed during the following construction activities: Trench work in the dry to lay the replacement stormwater outfall Excavation of the splash pad foundation if the excavation area is isolated from the water column by a coffer dam Grouting to abandon the existing stormwater outfall Pile removal Over-water construction work on the shiploader structure Over-water casting of concrete pile caps and trestle decking on the shiploader structure Concrete filling of steel piles Water Quality Protection and Monitoring Plan

18 Water Quality Monitoring Plan The monitoring and inspection procedures outlined in the following subsections will be implemented during visual monitoring Monitoring Parameters The following parameters will be assessed during visual monitoring: Turbidity Sheen Construction debris in the water Operation and effectiveness of BMPs Monitoring Schedule The frequency of visual monitoring will be as follows: Ongoing monitoring by Contractor during construction operations Twice daily monitoring by the Project Engineer or Environmental Manager Immediate monitoring if notified by the Contractor of a potential water quality exceedance, followed by ongoing monitoring until water quality returns to acceptable conditions Monitoring Locations Visual monitoring will be performed at the following locations: For BMP performance, at the location of the active operation For turbidity, within 300 feet downstream of any relevant construction activities For visible sheen, at the point of discharge to the river For construction debris, including wet concrete, at the point of discharge to the river Note that multiple activities requiring monitoring may be occurring simultaneously. 3.2 Instrumented Monitoring Instrumented monitoring will be performed during the following construction activities: Any in-water earthwork activities that are in direct contact with the water column; Water Quality Protection and Monitoring Plan

19 Water Quality Monitoring Plan for example, excavation of the splash pad foundation, if such work is performed without use of a coffer dam, or any other ground-disturbing activities that must be performed in the water due to unusually high water levels, scheduling constraints, or other field contingencies As a possible contingency measure in response to a visual observation of a significant turbidity plume, to better assess compliance with water quality standards and the effectiveness of any supplemental BMPs that may be implemented to control turbidity The monitoring procedures outlined in the following subsections will be implemented during instrumented monitoring Monitoring Parameters Real-time field measurements of the following water quality parameters will be collected during instrumented monitoring: Turbidity (in NTU) ph (in standard units) Monitoring Schedule If instrumented monitoring is required, it will consist of two rounds of measurements each day. If any exceedances of water quality criteria are observed at any time during the monitoring program and it is determined that the exceedance is caused by construction activities rather than an ambient background condition, then the contingency response and notification procedures will be initiated as described in Section Monitoring Locations During each monitoring event, turbidity and ph will be measured at three stations: 1. The Compliance Station is at the edge of the mixing zone 300 feet (91.4 meters) downstream from the construction activity. Compliance with water quality criteria will be evaluated at this station. Water Quality Protection and Monitoring Plan

20 Water Quality Monitoring Plan 2. The Early Warning Station is at the mid-point of the mixing zone, 150 feet (45.7 meters) downstream from the construction activity. The objective of the Early Warning Station is to become quickly aware of possible water quality excursions at the construction site and to be able to adjust construction operations and BMPs before an exceedance occurs at the Compliance Station. 3. The Background Station will be positioned approximately 500 feet (152 meters) upstream of the project site and beyond the influence of construction activities. The Background Station should be located along a part of shoreline with comparable water depth and other physical characteristics, including riprap armor. This station will be monitored during every event because the turbidity criterion is based on an acceptably small increase above ambient background levels in the river Monitoring Depths At each monitoring station, measurements of turbidity and ph will be made at three depths in the water column: 1. Surface: Within 3 feet (approx. 1 meter) of the water surface. 2. Middle: At the mid-depth of the water column. 3. Bottom: Within 6 feet (approx. 2 meters) of the river bed. 3.3 Record Keeping The Project Engineer or Environmental Manager will keep a written record of twice-daily monitoring activities and inspections during both visual and instrumented monitoring. These records will be maintained in project files and provided to the Washington State Department of Ecology (Ecology) if requested. Water Quality Protection and Monitoring Plan

21 4 CONTINGENCY RESPONSE AND NOTIFICATION PLAN 4.1 Contingency Measures In the event of an exceedance of water quality standards as observed during visual or instrumented monitoring, personnel will immediately stop work and attempt to assess the source of the impact or exceedance. Once the source has been identified, personnel will implement control measures to prevent further occurrences and limit additional environmental impact. Monitoring will continue to confirm that the control measures are effective and the observed water quality exceedances have been mitigated Visible Turbidity Plume In the event a significant turbidity plume is observed during visual monitoring, construction operations and BMPs will be thoroughly inspected to identify the source of the turbidity exceedance, and appropriate operational controls, engineering controls, or enhanced BMPs will be implemented to reduce turbidity to acceptable levels. A significant plume will extend the entire length of the mixing zone and remain visible 300 feet (91.4 meters) from the construction activity. Based on the shape and extent of the turbidity plume, it should be evident that the plume is sourced from a site construction activity rather than an anomalous background condition. If a visible turbidity plume is evident at the compliance boundary, follow-up instrumented turbidity monitoring may be initiated to better assess compliance with water quality standards and to track the effectiveness of any supplemental controls or BMPs that may be implemented. Instrumented monitoring is described in the next section Instrument Field Monitoring Contingent instrumented monitoring for turbidity and ph may be implemented in certain conditions, as described in Section 3.2. Field parameter measurements will be compared with the water quality criteria specified in Table 1 (see Section 1.2). Compliance with water quality criteria will be determined at the Compliance Station. If there is an exceedance of water quality criteria at the Compliance Station, the following sequence of events will be initiated: Water Quality Protection and Monitoring Plan

22 Contingency Response and Notification Plan 1. Evaluate the concurrent measurements at the Background Station to determine whether the exceedance is caused by ambient river conditions versus site-related construction activities. 2. Re-take field measurements 5 minutes later at the Compliance Station to confirm (or not confirm) the exceedance. 3. If the exceedance is confirmed and is attributed to construction activities, immediately notify the Contractor and Project Engineer. The Contractor will be directed to immediately modify operations and/or implement additional BMPs to mitigate the exceedance. 4. Re-take field measurements at the Compliance Boundary 30 minutes later, after additional BMPs and/or operational modifications are implemented. 5. Notify Ecology of the exceedance, actions taken to mitigate the exceedance, and the results of the follow-up measurements. If the water quality exceedance continues to persist, even with additional BMPs and/or operational modifications, a path forward will be discussed with Ecology. The path forward could include some or all of the following: a. Implement more aggressive BMPs or operational modifications. b. Implement more intensive monitoring to better track the growth or dissipation of the plume. c. If options (a) or (b) are not successful at controlling the water quality exceedance, it may be necessary to stop work to further assess the source of the exceedance, identify effective mitigation measures, and allow the water column to recover Construction Debris in Water In the event of an observed release to the water of deleterious construction debris, the Contractor will cease operations and recover the debris. Repairs to equipment, containment measures, and/or modification to work practices will be made prior to resuming work. Once the source has been identified and addressed, work may proceed. If the debris is environmentally innocuous (e.g., old concrete, steel, etc.), work may proceed simultaneously with recovery efforts. Water Quality Protection and Monitoring Plan

23 Contingency Response and Notification Plan Distressed or Dying Fish In the event distressed or dying fish are observed at the construction site and are attributed to site activities, work will immediately stop and Ecology, the Washington Department of Fish and Wildlife, and the National Marine Fisheries Service will be contacted. The condition of the fish (dead, dying, erratic behavior, etc.); an estimate of the number, species, and size of fish in each condition; and the location of fish relative to construction operations will be noted. If any dead listed species are present, samples will be frozen for possible agency inspection. Additional fish and/or water sampling may be conducted at the direction of the resource agencies Discharge of Oil, Fuel, or Chemicals In the event of a discharge of oil, fuel, or chemicals (including wet concrete) into state waters, containment and cleanup efforts shall begin immediately and be completed as soon as possible. Cleanup includes appropriate disposal of any spilled material and cleanup material. The following agencies will be immediately notified: Ecology s Spill Response Office at (360) Washington State Emergency Mangement at (800) National Response Center at (800) Notification For any work that is out of compliance with water quality standards, personnel will immediately stop work and notify the Project Engineer or Environmental Manager, who will notify Lori Ochoa, Federal Permit Manager, Ecology Southwest Regional Office at (360) A detailed written report will be submitted to Ecology within 5 days or as otherwise specified in the Section 401 Water Quality Certification for this project. The report will include the following information: Nature and extent of the water quality exceedance, including detailed visual observations and, if appropriate, field parameter measurements Identification of the likely cause of the exceedance Description of control measures or BMPs implemented to mitigate the exceedance Notifications to agency, including timing and names of agency personnel contacted Water Quality Protection and Monitoring Plan

24 Contingency Response and Notification Plan Documentation that control measures were effective at mitigating the water quality exceedance, thereby allowing construction work to resume Water Quality Protection and Monitoring Plan

25 5 REFERENCES Washington State Department of Ecology (Ecology) Guidance on Controlling Turbidity in Nearby Waters from Ground Improvement Work for Seismic Events. Memorandum from K. Carroll, WSDOT Liaison, to K. Susewind, Ecology, July 13, Water Quality Protection and Monitoring Plan

26 FIGURES

27

28