J
Conti Environmental, Inc, July 27,1998
RR300U8U M MAVERICK MAVERICK Construction Management Services, Inc.
July 27,1998
Randy Sturgeon U.S. Environmental Protection Agency Region III 1650 Arch Street Philadelphia, PA 19103-2029
RE: Draft Work Plans Galaxy/Spectron Site
Dear Randy:
Please find enclosed a copy of the draft works plans for the removal action construction at the Galaxy /Spectron Site located in Elkton, Maryland for your review and approval. Included in this package are the draft Health and Safety Plan, Erosion and Sediment Control Plan, and the Project Execution Plan. Per your request, a copy of each plan has been sent directly to the Maryland Department of the Environment and the U. S. Army Corp of Engineers.
We are targeting August 10, 1998 for mobilization to the site. If there is anything we can to expedite the approval of these work plans, please do not hesitate to call on us.
If you have any questions, please contact me at (508) 733-2900 or page me at (800) 505- 4740.
Si
•lore Construction Manager
cc: Michael Parr (w/o attachments) Rick Grills, MDE (w/attachments) Ramon Benitez, USAGE (w/attachments)
P.O. Box 60700 197M Boston Post Road West King of Prussia, PA 19406 Suite 356 610-783-6202 Marlboro, MA 01752 610-783-6231 FAX RR300U85 508-485-7872 FAX 508-485-8340 GALAXY / SPECTRON SITE
ELKTON, MARYLAND
REMOVAL ACTION EXECUTION PLAN July 27,1998
TABLE OF CONTENTS
CONTI ENVIRONMENTAL, INC
SECTION DESCRIPTION PAGE NO.
I. Introduction 1
II. Pre-Con struct ion Meeting 3
III. Mobilization 3
IV. Fence Removal and Reinstallation 5
V. Clearing and Grubbing 6
VI. Water Management 7
VII Demolition 11
VIII. Site Grading 12
IX. Installation of Concrete Cast-In-Place Cone. Walls 13
X. Groundwater Collection System 16
XI. Barrier Layer 17
XII. Protective Cover 19
XIII. Habitat Restoration 21
XIV. Demobilization 23
XV. Traffic Control Plan 24 GALAXY / SPECTRON SITE ELKTON, MARYLAND
REMOVAL ACTION EXECUTION PLAN
CONTI ENVIRONMENTAL, INC
I. Introduction /
A. Project Objective: The objective of this project is to physically separate the surface water flow in the Little Elk Creek from the subsurface dense non-aqueous phase liquid (DNAPL) impacted subsurface flow and to isolate, collect, and treat the DNAPL-impacted subsurface flow, however permanent treatment system installation is not part of this contract. This objective shall be accomplished by isolating the surface water flow in the creek, constructing grounHwatep cutoff walls atW upstream and downstream limit of the remedy, installing a groundwater collection system, installing a barrier layer along the stream bed, and installing a protective cover within the creek channel over the barrier layer, and reconstructing the riparian and stream habitat. Conti Environmental, Inc. (CEV) will perform this work in accordance with the approved 100% Design plans and specifications as submitted by Advanced GeoServices Corp. to the USEPA.
A complete set of Contract Documents will be maintained in CEV's on-site field office as a Project Record / As-Built set of plans. The documents will be labeled as such and will not be used for any other purpose and will not be removed from the trailer under any circumstances. This set will be updated regularly as work progresses on the site. At the conclusion of the project, the plans will be forwarded to the Construction Manager as a formal submittal per the requirements of Section 01050 of the Contract Documents.
Galaxy/Spectron Remedial Action Conti Environmental, Inc. Removal Action Execution Plan(Draft) 05/01/9&- ___ i Page 1 flR300l*87 B. Project Team p \ CEV organizational plan for thi galaxy/Spectron site is based upon fielding an experienced, independent project management team supported by key Corporate managers. The CEV project team consists of personnel experienced in hazardous waste site and Superfund remediation. The key personnel to be assigned to this project are outlined below. Resumes of the key personnel can be found in CEV's Proposal to Maverick Construction Management Services, Inc. dated jmW *> 1998.
• Mr. James V. Stewart: Vice President of Operations • Mr. John Czapor: Director of Environmental Services • Mr. Al Aballo: Corporate Health and Safety Officer • Mr. Robert Scerbo: Project Estimator • Mr. Paul Dutko: Quality Control Officer • Mr. Leonard Nicaretta: Project Superintendent • Mr. Andrew C. Weber: Project Engineer/Manager • Mr. Carlos Narciso: Labor Foreman • Mr. Bruce Henderson: Health and Safety Officer (Haz-Tech Corp.) • Site Field Engineer: T.B.D.
C. Sequence of Major Operations Removal Action Construction at the Galaxy/Spectron site involves numerous operations including but not limited to the following items. Each item will be discussed in detail within this report:
• Submittals: Work Plans, Health and Safety Plan, etc. • Preconstruction Meeting • Mobilization • E&S Controls • Clearing and Grubbing • Water Management • Demolition • Site Grading / • Installation of Concrete^ casX-In-Place Concrete Walls s
Galaxy/Spectron Remedial Action , j Conti Environmental, Inc. Removal Action Execution Plan(Draft) J 05/01/98 Page 2 HR300U88 Groundwater Collection System Water Diversion System Installation of Barrier la>jer Installation of Protective Layer Construction of Gabion Walls Habitat Restoration Demobilization
II. Pre-Construction Meeting
Prior to mobilization at the site, a Pre-Construction Meeting will be held at a location, date and time determined by Maverick Construction Service, Inc. (Construction Manager). This meeting will serve multiple purposes including but not limited to the following: • Introduce the Project Team • Review the Project Schedule • Review the work plans (Including the Health and Safety Plan) • Review the Health and Safety Plan ( Including the Air Monitoring Plan) • Discussion of required/non-required permits: Both at the Local & Gov't levels • Mobilization Issues: Field Office Coordination <;7b v /7'!"i> *i
III. Mobilization
Upon required approvals, CEV will commence mobilization operations. An area for the field office compound and material laydown areas will be prepared. The field offices consisting of mobile trailers will be set-up on the Plant property inside the entrance gate on the south end of the Plant prqperty. See Attachment No. 1, Site Plan for the proposed compound layout. The trailer compound will consist of two identical 12' x 60' office trailers. One will be for the use by Maverick Construction Management Services, Advanced GeoServices Corporation, Army Corps of Engineers, USEPA, and^laryiand Dept. of the Environment. The second trailer will be for CEV and it's subcontractors. A third, smaller trailer will be for the labor force to use as^kreakroom/lunch area. Telephone, electric and drinking water services will be installed as necessary.
Galaxy/Spectron Remedial Action Conti Environmental, Inc. Removal Action Execution Plan(Draft) 05/01/98 Page 3 RR300U89 Material laydown areas will be located on the Plant property including under the existing canopy and on the non-plant side (east side) adjacent to Little Elk Lane.
CEV intends to mobilize several pieces of equipment to be included with the initial activities. These will include a Komatsu PC-400 Excavator, Komatsu WA- 400 Loader or equal, 37-P Dozer, Combination Loader/Excavator, D300 Rear Dump truck and a Tool Container. Equipment mobilized on-site will be kept within the Plant property. ^ Water on site will be handled in the followin&4nanner. Drinking water will be supplied by a service such as Great Bear, de^onning water will be clean upstream water held in a 5000 Gal Tank on-site. A portable handwashing station will be set-up adjacent to the trailer compound along with an emergency eye wash station.
c CEV will acquire the services of a Maryland Licensed Surveyor to perform ' : ,/• survey operations on site. The Surveyor's qualifications will be submitted to the Construction manager for review and approval. Upon approval, the Surveyor will mobilize on site, establish survey control per Plan Sheet No. 1 of the approved 100% Design and set the clearing limits at the direction of CEV and the Construction Manager. The trees within the clearing limits which are to remain will be clearly marked with survey ribbon. The Surveyor will establish the baseline survey and confirm the existing topography. The Surveyor will be responsible for maintaining site control throughout the project and layout of the major work operations/!.e. Groundwater Collection System, Concrete Walls, Rock Anchor Locations, etc/^The field equipment utilized by the Surveyor will 1>^"' enable him to collect necessary data in the field and download at their office in preparation of required As-Builts.
All required health and safety and environmental monitoring will be implemented prior to the start of intrusive activity. The "kick-off meeting will incorporate this Site Specific Training and will be conducted by the Site Safety and Health Officer. CEV will monitor the perimeter of the site with photo-ionization detectors'(PID's) equipped with warning alarms to indicate when action levels are exceeded. A detailed discussion of perimeter monitoring will be included with the Site Health and Safety Plan under separate coyer, /
Galaxy/Spectron Remedial Action Conti Environmental, Inc. Removal Action Execution Plan(Draft) 05/01/98 Page 4 AR300U90 Guy wires on existing utility poles within the Plant property which may interfere with the proposed work will be relocated at the direction of Delmarva Power Company. The guy wires will be realigned by the Engineering Department Delmarva to remain out of the work area.
CEV will utilize the services of a Licensed Security Company to watch the site' during non-working hours, including weekends. The guard will be located in CEV's field trailer, but will be required to walk the site outside the exclusion zone on a hourly basis. A log will be kept in the field trailer for the/guards to input their findings from the site surveillance. A meeting betweerfathe Construction Manager, CEV and the Security Company will be held on-site prior to the start of • work activities to establish standard operating procedures to be followedAll gates to the site and plant will be locked at all times during non-working hours \ t* During work hours, all visitors will be directed to sign in at the Construction Manager's field office trailer. Signs will be posted at the south gate to direct visitors to the trailer. The gate on the north end of the Plant will be closed and locked except for material deliveries. Areas of the Plant property will be closed off for access with the use of orange safety fence. These areas would include any unsafe buildings, tanks, etc.
IV. Fence Removal and Reinstallation
The existing 6' high chain link fence will be removed as required to provide access to the site for the remedial activities. The removed fence will be stored on- site. CEV will make every effort to leave existing fencing intact until necessary to remove it to progress with operations. Temporary fencing will be utilized for site security in those areas where the permanent fence is removed. The exclusion zones will be delineated with orange safety fence to avoid unauthorized entry. Permanent fence will be reinstalled around the Plant upon the completion of the remedial action
Galaxy/Spectron Remedial Action Conti Environmental, Inc. Removal Action Execution Plan(Draft) 05/01/98 Page 5 RR300l*9 V. Clearing and Grubbing
Upon completion of the Erosion and Sedimentation Controls and the establishment of work limits by construction survey, CEV will begin clearing and x._ grubbing operations. Refer to the Erosion and Sediment Control Plan for the '-^proposed limits of clearing. Any trees within the clearing limits which are to remain will be clearly marked with survey ribbon. Clearing will commence on the non-site side of property at the north end and progress in a southerly direction. ^ CEV will work with the Construction Manager and the Engineer to review the *h areas to be cleared. CEV will take measures to identify and protect trees not ^ designated for clearing, and will only clear those trees that are absolutely /<- necessary to for the proposed construction. Aboveground vegetation will be ^x chipped and utilized where possible as mulch. Any above ground vegetation 4 which cannot be utilized as mulch will be disposed of off-site as non-hazardous -^TV waste. Any below ground materials which cannot be utilized as fill below the cap 7* area could potentially be disposed of off-site as hazardous waste as one option. — Other available options should be discussed. Below ground materials from areas""] 1^^ outside the "contaminated" areas will be disposed of off-site as non-hazardous waste. CEV will remove soils from the below ground materials prior to being •-' removed from the work area. In order to minimize bulk and to manage a more homogenous waste material, CEV will utilize a tub grinder to pulverize "grubbed' material. This will allow more material to fit into a disposal container, thereby minimizing disposal costs. Equipment to be utilized in this operation will consist of a PC-220 Excavator with a grapple, a loader and a small dozer. Laborers will utilize chain saws and a chipper to handle the smaller trees/bru
CEV will locate the tub grinder on the plant property. The unit will <0e placed in an area of existing asphalt. A poly liner will be placed on op of the asphalt and below the tub grinder in order to keep the surrounding are; L 'clean'. The poly area will be bermed on all sides. Grubbed materials will be se )arated depending on \ location of origin to maintain proper containerization and offsite disposal options, \ All material stockpiles will be covered with poly to eliminate odors and run off j- due to rain events. It is not anticipated'that dust will be a problem, however water Vjpn-site will be available for dust suppression. At the conclusion of the tub
Galaxy/Spectron Remedial Action Conti Environmental, Inc Removal Action Execution Plan(Drafl) 05/01/98 Page 6 RR300U92 grinder operation, CEV will dispose of the poly working pad with the last container.
VI. Water Management
A. Stream Diversion System Installation After soil erosion control devices and clearing and grubbing are performed, CEV will install its water flow management devices to allow for further work in the stream bed. CEV proposes to utilize two electrical submersible pumps. Each pump is rated at 5,000 gallons per minute. Our proposed combination of pumps can handle water flow up to 10,000 gallons per minute. This is more than adequate to handle the stream base flow of approximately 8,100 gallons per minute. The water from the pumps will be channeled through an 18" diameter high density polyethylene (Butt Fused) header pipe. The discharge line will be installed on the plant side of the site and CEV will completely bypass the work area, discharging the water on the concrete surface at the top of the downstream dam. This bypass and discharge operation will be continuous throughout the project. The discharge line will include a high velocity discharge sock, made of woven geotextile, to prevent siltation at the discharge point. CEV will visually inspect/monitor the discharge for sediment and turbidity. The two pumps at the upstream locations will also be equipped with filter socks as stated previously in Section IV. Please refer to the Erosion and Sediment Control Plan for a description of the erosion and sediment control devices proposed to use during the water diversion operation.
CEV is cognizant of the concern the neighbors may have regarding the noise level of the pumps. The equipment to be used on this project will be newer, quieter running machines. Sound suppression technology has advanced considerably over the recent years and CEV believes the noise levels should not be a problem for the neighbors. The pumps will be equipped with automatic controls to assure 'overpumping' does not occur. The water level above the upstream dam will not be lowered below required elevations. The pumps will be set into location and removed from the creek via 75 Ton Crane. The crane will be operated by a licensed crane operator. The CEV foreman will be the sole person responsible for hand signals to direct the operator. The crane will be set on the access road on the
Galaxy/Spectron Remedial Action Conti Environmental, Inc. Removal Action Execution Plan(Draft) 05/01/98 Page 7 RR300U93 non-site side of project. No additional clearing should be necessary to the pumps in position.
One pump will be located within the existing concrete sump along the western side of the creek above the upstream dam. The existing floodgates will be utilized in diverting water into the sump. As a contingency, if the floodgates are non-operational, CEV will set the pump in the low point of the middle of the stream above the dam on a steel plate to minimize sediment disturbance. As a secondary control of sediment, the steel plate will be equipped with a 12" high welded steel edging perpendicular to the plate around the perimeter. The second pump will be situated in the plunge pool at the base-of the upstream dam. Each pump will also be equipped with a 'screen' on the intake to prevent sediment intrusion. The two pump discharge lines will be installed in a manifold arrangement allowing both lines to discharge to the 18" header lineyr
The discharge/bypass line will be run on grade with the exception of the construction entrance(s). At these points the pipe will be buried below a steel plate for protection. The discharge line will be installed below the Providence Road Bridge. The discharge line will be anchored along the plant side with stainless steel straps around the pipe and secured to the ground with metal pins. The discharge pipe will be set on the upper concrete apron of the lower dam with the discharge end extending beyond the apron over the dam and with a 180 degree bend the effluent will discharge against the face of the downstream dam. The wall face will act as an energy dissipater, thus causing no additional scouring or erosion at the base of the downstream dam. The piping will be secured to the existing downstream dam via stainless steel straps around the pipe anchored with Hilti Concrete Anchors or a similar product. The discharge end of the pipe will have a steel cage constructed around it to prevent anyone from getting to close to the active discharge. The steel cage will be anchored to the dam in the same fashion as the discharge pipe.
Per the contract plans, at the limit of work at the south end of the project there appears to be an area which will pond water due to the existing grades. This area is approximately 90 feet north of the downstream dam. Following the base flow diversion, CEV will divert water from outside the work area on the south by means of a portable 3" pump discharging to the top concrete apron on the
Galaxy/Spectron Remedial Action Conti Environmental, Inc. Removal Action Execution Plan(Draft) 05/01/98 Page 8
X downstream dam via a rubber or canvas hose. The sediment precautions discussed with the upstream diversion will be consistent with this downstream pumping operation. Subsequent to the ponded water diversion, CEV will then excavate a small trench to allow future stormwater buildup to flow around the south east end of the downstream dam. The existing topography is ideal for such a diversion. The area has a gradual elevation change and is currently lined with boulders and riprap sized stone. CEV will restore the area when work is complete to its natural contours.
Upon completion of the required work within the streambed, the pumps will be turned off, the bypass pipes disconnected and flow will be allowed to return to the creek. The water flow will be visually monitored to ensure the design is functioning satisfactorily
B. Groundwater Encountered During construction of the cast-in-place concrete walls and the groundwater^' collection system, CEV will open cut the trenches and displace any water encountered during excavation with concrete for the walls and stone aggregate for the groundwater collection system, The displaced water will dissipate within the c • work area. The subgrade will be graded to slope toward the site into a small channel with stone to allow water to flow through the work area to the sedimentation trap.
If any groundwater is collected during intrusive work activities, CEV will maintain a small water treatment system that/consists of one 20,000 gallon frac tank with a multi-media sand and carbon Galaxy/Spectron Remedial Action Conti Environmental, Inc. Removal Action Execution Plan(Draft) 05/01/98 Page 9 AR300U95 Sampling of the effluent will be performed at a frequency satisfactory to Maryland surface water discharge requirements. CEV will e§ja5lish a monitoring program for the water treatment plant satisfactory to M.D.E. CEV will provide MDE with a schematic of the proposed treatment system coupled with a brief analysis of the potential loading to the system. Specifically, CEV will evaluate existing data to determine representative concentrations of organic compounds in the groundwater. Based on this information, CEV will project the loading to the plant for a given volume of water and, in consultation with the treatment plant vendor, develop an estimated volume at which breakthrough of the carbon unit would occur. CEV will also perform some analysis to meet applicable Discharge Monitoring Requirements; this will consist of analysis for selected representative compounds. This sampling would occur at the discharge of the first carbon canister, which would serve the dual function of monitoring forcarbon breakthrough and ensuring overall compliance with discharge li Collection and treatment of water will only be necessary when a localized area can not be drained and_wiHJmpede on the progress of specific tasks of the project. For example, during construction of the lower cutoff wall, any groundwater encountered will be pumped via a small portable pump to the treatment plant for processing. ~-j C. Jersey Barrier Diversion Upon completion of the cast-in-place concrete cutoff walls and the Groundwater Collection System, CEV will continue to utilize the pumps to keep the streambed dry; however, at this point, CEV will install a precast "Jersey" barrier curb diversion on the longitudinal anchor wall with an initial diversion section angled from the upstream cutoff wall allowing for redirection of water, as required. As previously stated, the two pumps will be constantly diverting water at a maximum rate of 10,000 GPM, if a rain event causes water to come over the dam it is not anticipated that the volume will breach the jersey barrier diversion system adjacent to the upstream cut-off wall. At this point in construction, it is very critical to direct the water flow in the stream after a rain event. The ability to redirect the flow is critical to ensure that sections of completed work are not Galaxy/Spectron Remedial Action Conti Environmental, Inc. Removal Action Execution Plan(Draft) 05/01/98 Page 10 flR300l*96 destroyed after a significant rain event. CEV would direct water to the "wide" side to allow for construction of the first phase of work in the "narrow" side of the stream. CEV will reverse direction of the stream flow after the "narrow" side of the stream is completely constructed and secured, as specified. X Installation of thejersey barrier system is as follows; an excavator will place each 20' length oj/#arrier on top of the longitudinal wall proceeding from the north to the south-t/ The barriers will be installed end to end in a tongue and groove fashion. The precast holes on the bottom flange on side of the barrier facing the east side will line up with the center 'slot' in the longitudinal wall. A piece of wood will be installed in each precast hole to anchor the barrier to the wall. A small amount of fill will be graded under the west facing side of the barrier to stabilize and level each section of barrier. Steel pins will be installed through the holes in the bottom flange to anchor the barrier to the streambed. 6-mil poly will be placed under the fill and run up and over the top of the barrier. CEV expects this procedure to be adequate to keep anticipated rain events from affecting the construction area, however if a 'flood' should breach the system, CEV will have the geotextile working mat installed in disturbed areas to prevent sediment transfer and the water will run as it does now. After the water has subsided CEV will resume work in the construction area. Upon completion of the 'narrow' side gabion work, the jersey barrier system will be relocated from the 'wide' side to the 'narrow' side in order to divert the flow of water, as necessary to the 'narrow' side. Anchoring the barrier with steel pins will not be done due to the fact the gabion mats will be installed at this point on the narrow side. VII. Demolition CEV will dismantle the foptbfidge and will salvage/store the material on site on the Plant pro^ejly-^^-Jfee^butments and piers will be demolished with a backhoe- mounted hydraulic breakbr^Jhetubble will be sized to a 4" - 8" dimension. All rubble wilrbrsteam cleaned and stored on site for use during restoration activities. The centerpfe( • r-^ from the Providence Road Bridge appears to be completely removed to date, however CEV will confirm and if necessary the Galaxy/Spectron Remedial Action Conti Environmental, Inc. Removal Action Execution Plan(Draft) 05/01/98 Page 1 1 &R300U97 7 A« footing will be demolished to 6" below the liner suj>grade. The chain link fence around the small block building and the transformer will be removed and stored as necessary. The transformer area, and small blodc Building will be demolished above grade only, as required. A PC-400 Excavaior will be used to raze the structures and load into roll-off containers. The work will be performed from within the Plant property. Water within the 5000 Gallon on-site tank will be available for dust suppression if necessary. The debris will be sampled and upon analytical results of the samples, a disposal facility will be identified and submitted to the Construction Manager for approval. The roll-off containers will be covered and located within the plant property out of the way of day to day activities. VIII. Site Grading A. Remove Large Boulders and Rubble form Stream Bed Large Boulders and Rubble will be removed as required to meet the subgrade specification. An excavator will load the boulders / rubble onto the screen located in the streambed. The screen will segregate the stone and at which time the larger stone will be steam cleaned within the stream bed, placed on poly and stockpiled for use later in the project as gabion stone, or construction of the Boulder Islands. Additional boulders/rubble will be deposited within the plunge pool below the upstream dam. The steam cleaning operation will generate very little water within the streambed and the removed sediments will also be deposited within the streambed. The east side (non-site) side of the property from the stream bank to the location of the proposed longitudinal wall will be rough and fine graded in the same operation due to the absence of any groundwater collection system on the east side. Therefore CEV will install the working mat as the grading operation progresses down the east side. The mat will be anchored wjthjjtakes . Following initial grading of the wide side (or west side) of the site^ (bouldeP/riibBle) CEV will install the working mat to minimize sediment disturbance. As previously stated in section IV, the subgrade will be sloped to the plant side to facilitate drainage. Galaxy/Spectfon Remedial Action Conti Environmental, Inc. Removal Action Execution Plan(Drafi) 05/01/98 Page 12 RR300lt98 B. Cut / Fill Operation The amount of grading will be minimized to maintain the natural irregularity existing within the creek, however some cutting/filling of the creek bed and bank materials will be necessary in order to provide a stable base for support of the liner and the gabion mat/wall. The cut/fill operation will be performed to achieve the grades shown on the approved 100% Design drawings. Prior to construction of the concrete walls or the groundwater collection system, the grading will be rough, adequate to be able to perform these operations on grade. During and after construction of tlie concrete walls and the installation of the groundwater collection system ^ Stream bed sediments will be cut and screened with a Portable Reed Screen-Alr^quipped with a 2" deck and a 3/4" deck. The screening operation will be performed as a dry operation. CEV proposes to perform the screening operation within the streambed. Material will be segregated according to size and stored and stockpiled for future use or reinstalled in areas requiring fill. Material between 2" and 3/4" will be utilized around the collection system, however availability of this produced size may not be consistent therefore it may be necessary to bring in an approved stone source during the collection system installation. For more information on the groundwater collection system see Section X. IX. Installation of Cast-In-Place Concrete Walls Installation of the Upstream and Downstream Cut-Off Walls are intended to provide rigidity and stability against static and dynamic forces, provide a watertight anchorage of the barrier layer and cutoff the horizontal movement of water into the removal action area from upstream and prevent the escape of water from within the removal action area of the downstream limits. The longitudinal wall will define the limits of the temporary secondary channel. The top of the longitudinal wall will be flush with the top of the gabion mat and will separate the Galaxy/Specfron Remedial Action Conti Environmental, Inc. Removal Action Execution Plan(Draft) 05/01/98 Page 13 AR300U99 barrier components of the primary and secondary channels. The cross-stream walls will extend the width of the channel, between the site side stream bank and the opposite bank. Construction of the Cast-In-Place Concrete Walls will be performed after the water bypass system has been installed. A. Upstream and Downstream Cut-Off Walls Excavate the 'lower' section of the wall to the top of the altered rock. CEV will dig in layers until the altered rock has been identified. The altered rock will be judged by the on-site Resident Engineer. A concrete pump will be setup adjacent to the excavation, concrete will be tremied into the trench to form a monolithic base wall. The concrete will be placed with a 4 - 5"' slump to ensure a tight seal across the top of the rock. A mechanical concrete vibrator will be used to consolidate the concrete during the placement operation. An experienced concrete laborer will insert the vibrator in quick vertical movements careful not to 'move' the concrete laterally with the vibrator thus causing possible segregation of the concrete. A backhoe will continually be cleaning the top of the rock with the bucket ahead of the concrete operation. Two PVC water stops will be installed on top of the monolithic base as per Addendum 2 detail. During construction of the base pour, 6" dia corrugated steel sleeves will be installed from the bedrock to the surface. These sleeves will allow the rock anchors to be installed after the wall has been poured. Upon completion of the monolithic base wall, CEV will construct the 'middle' section of the wall. This section is reinforced with ASTM a 615, Grade 60 deformed reinforcing bars, typical for all rebar on this project. This section will be cfree formed' as was the base section. The excavated earth walls will act as the form work thus allowing construction to continue without having to strip the forms and backfill the wall. The reinforcing steel will be lowered into place by use of a backhoe. The rebar will be installed as a pre-assembled cage. The concrete will be placed using a concrete bucket on a PC-400 Excavator. A PVC water stop will be installed along the top of this section in a similar fashion as was done with the base section. Note: A 2'-3" wide strip of 45 mil Geomembrane will be inserted 6" into the concrete as it is cast to act as a tie-in for the barrier system Geomembrane. This strip will be inserted by hand at the time of the pour. The concrete vibrator will ensure proper consolidation around the geomembrane. In order for the strip to Galaxy/Spectron Remedial Action Conti Environmental, Inc. Removal Action Execution Plan(Draft) 05/01/98 Page 14 RR300500 remain in the concrete 6", the end of the strip will be tied-off with steel wire to the adjacent rebar dowels for the top section . Once the concrete has 'set', the wire ties will be cut and the three inches at the end of the strip will be cut off in order to have a smooth edge in which to weld to later with the geomembrane work. See Section XII for more details on the placement of the Geomembrane. Rock Anchors: Rock Anchors will be installed within the 6" dia sleeves installed during the base pour at a 10' on centers. CEV will use a track mounted rig to drill the 2" +/- hole through the 'middle' and base sections and into the intact rock approximately 2'. Each anchor shall consist of a single 1" dia threaded rod with a mechanical anchor assembly that can be expanded after insertion into the drilled hole to provide anchorage to intact rock. Each rock anchor shall be fitted with a heavy duty hex nut, washer and 8" square x 1" thick steel plate. The drilling operation is not expected to generate dust, however if does becomes a nuisance problem, CEV will suppress the dust with the same clean diverted stream water being used to keep the geomembrane moist. The entire assembly will be grouted in place and concurrent with the grouting operation the anchor assembly will be tightened down enabling the mechanical anchor assembly to 'lock' the intact rock. See Attachment No. 2 for manufacturers installation and grouting procedure. Following the installation of the rock anchors, CEV will form the 'upper' section of the upstream and downstream cutoff walls. This section will be 2' wide by 1' high with a 1" wide by 6" deep slot running lengthwise on top of the wall. This slot will used during water diversion operations as previously stated within this report. Following proper curing, CEV will strip the forms. CEV will cast concrete samples in standard molds to be taken to an approved laboratory and strength tests performed. CEV will report the test results to the CQA Monitor. B. Longitudinal and Mid-stream Anchor Walls The construction of the longitudinal wall and the mid-steam anchor walls will be in a similar fashion as the upstream and downstream cutoff walls. The depth of these walls are much shallower than the cutoff walls and therefore the unreinforced monolithic base pour will not be required on the longitudinal and Galaxy/Spectron Remedial Action Conti Environmental, Inc. Removal Action Execution Plan(Drqfi) 05/01/98 Page 15 RR300501 'cross' walls. CEV will excavate to the proposed bottom of the wall at which point, a licensed Surveyor will layout the locations of the rebar anchors, staggered 10' on centers. CEV will drill for the rebar anchors in the following manner; Auger through the stream sediment, insert a 6" dia steel sleeve inside the auger and pull out the auger. Install rock drill bit and proceed to drill through the altered granitic gneiss material and proceed into the intact granitic gneiss layer 2'. Upon completion of the drilling, CEV will grout the hole from the drilling and insert the #8 rebar anchor to extend approximately 18" above the bottom of the wall. The excavated wall area will then be cleaned prior to placement of the reinforcing steel or the 4000 psi concrete. CEV will insert a 2' wide strip of 45 mil Geomembrane into the 'green' concrete 6" for future tie-in to the barrier system. See Section XII for more detail on the placement of the 45 mil Geomenbrane. A PVC water stop will be installed longitudinally on top of this section of the wall prior to the construction of the top section. CEV will form the top section of the longitudinal wall and the mid-stream walls in the same fashion as the top section of the cutoff walls. The 1.5' wide by 1' deep section will be formed including the 1" wide by 6" deep slot. CEV is considering the use of inserts for the anchor bolts into the concrete. The bolts would be placed at 6" O.C. during the formwork and would be incorporated into the concrete pour. The batten strip would the be installed over the bolts after the forms have been stripped. Reinforcing steel will be installed and 4000 psi concrete placed. CEV has extensive concrete placement experience and as always will provide a high quality end product. X. Groundwater Collection System The groundwater collection system will be situated within the prepared subbase and beneath the barrier layer. A licensed Maryland Surveyor will layout the location of the collection system. After excavation, the geotextile will be installed, the stone will be placed on top of the fabric and the piping will then be installed per the grades of the approved 100% design. The system will consist of 2 rows parallel to the stream flow and the connecting laterals of 6" dia corrugated polyethylene pipe with smooth interior walls and perforations installed parallel to Galaxy/Spectron Remedial Action Conti Environmental, Inc. Removal Action Execution Plan(Draft) 05/01/98 Page 16 AR300502 the stream alignment and The pipes will be backfilled with 3/4" - 2" stone. This stone may be generated from the subbase grading or the collection system excavation or may be from an approved off-site source. A non-woven geotextile will be wrapped around the stone/pipe. The 6" perforated pipes will collect the groundwater and tie into non perforated pipe which will be installed perpendicular to the stream alignment. The system will drain to 3 High Density Polyethylene (HDPE) Manholes located on the Plant side. CEV will install 8" non-perforated corrugated polyethylene conveyance pipe between the manholes. This pipe will be component of a future on-site water treatment system which is not currently part of this contract. XL Barrier Layer The approved design for this project separates the streambed reconstruction into 2 layers; the Barrier Layer which is on top of the prepared subbase and the Protective Layer which sits on top of the Barrier Layer. Both Layers will be detailed within this report. It is CEV's intention though to construct both layers or a 'complete' system on any given day during this phase of the project. Several safeguards have been installed to bypass and redirect water in the event of a rain event, however, to ensure that a section of previously completed work is not damaged or entirely destroyed by a rain event. CEV will complete only a limited footage of system each day but the system will be complete encompassing both the Barrier and Protective Layers. If a rain event should overcome our diversion systems then the water will simply flow over the streambed as the intended design calls for not causing any damage to previously constructed work. CEV will cease operations on further work in the streambed until the rain event has passed. The Barrier Layer is comprised of three components: A geotextile working mat which will be a 7.5 oz non-woven geotextile and be installed on top of the prepared subbase, a geosynthetic clay liner (GCL) installed on top of the geotextile working mat and a 45 mil scrim reinforced polypropylene geomembrane to be installed on top of the GCL. 1. Geotextile Working Mat Galaxy/Spectron Remedial Action Conti Environmental, Inc. Removal Action Execution Plan(Draft) 05/01/98 Page 17 RR300503 The geotextile working mat will be a 7.5 oz. non-woven geotextile laid out over disturbed areas as well as the prepared subgrade. 2. Geosynthetic Clay layer (GCL) The geosynthetic clay layer will be laid out and installed per the manufacturer's recommendations. The materials will be placed with the membrane side facing down. A 12" overlap between rolls will be maintained as per contract documents.. The GCL will be kept dry at all times, including stockpiled material. Upon placement of the GCL, the 45 mil scrim reinforced geomembrane will be installed on top in a timely fashion to prevent the GCL from becoming saturated. The leading edge of the GCL will be protected from the elements overnight or during work stoppages. 3. 45 mil Scrim Reinforced Geomembrane Prior to installation of the geomembrane, CEV will submit a field panel layout plan depicting the orientation of the panels and identifying each panel and seam. Upon approval of the panel layout plan, CEV will commence placement of the geomembrane over the GCL. Panels will be laid out and the seams welded in a timely fashion. Panels will overlap by 4" with the upstream panel over the downstream panel. Seaming: Each morning during geomembrane placement, CEV will run a test Seam. The test seam will be verified on the field tensiometer. Upon approval of the test seam by the CQA Monitor CEV will prepare the seams. The seams will be cleaned as necessary prior to work. As the seaming operation progresses, Non- Destructive testing will be performed by CEV and witnessed by the CQA. The purpose of the testing is to verify seam continuity. All tests will be recorded by CEV documenting the date, weather, seam location , name of tester and result of test. If a test fills, corrective action will be done to the seam and a new test will be performed. The Non-Destructive Testing will be performed with a Vacuum Box in accordance with ASTM D4437. Galaxy/Spectron Remedial Action Conti Environmental Inc. Removal Action Execution Plan(Draft) 05/01/98 Page 18 RR30050U Destructive Testing: CEV will have an independent laboratory destructively test field seam samples. The tests will be performed at a frequency of one test per 500 If of seam. The sample location shall be selected by the CQA Monitor. System Anchorage: CEV will furnish and install a continues batten bar at the geomembrane termination along the concrete walls. The batten will be 2" wide, 3/8' thick stainless steel, with 3/8" diameter holes centered along the length of the bar at 6" spacing per contract documents. CEV will pre-drill the anchor bolt holes, install the anchor bolts and place the flexible seal over and around the anchor bolts. The geomembrane will then be placed over the anchor bolts with at least 4" from the edge of the geomembrane. The batten bar will be installed immediately on top of the geomembrane and secured with the nuts and washers. A secondary seal system will be installed after installation of the anchor bolt / batten bar assembly. A 12" wide strip of 32 oz geocushion will be laid along the length of the batten and the geomembrane strip previously cast into the concrete will be pulled across the batten and welded to the primary geomembrane liner. XII. Protective Cover The Protective Cover system consists of three components; 16oz. non-woven geotextile, 32 oz, geocushion and the gabion mat. The Protective Cover will be installed above the Barrier layer. 1. Geotextile: CEV will install a 16 oz. non woven polypropylene geotextile over the 45 mil geomembrane. The geotextile will extend up the 1' side of the top section of the concrete walls and the proposed gabion mat. The geotextile will be placed with 6" overlap between rolls and the seams will be sewn per the requirements of the contract documents.. Galaxy/Spectron Remedial Action Conti Environmental, Inc. Removal Action Execution Plan(Draft) 05/01/98 Page 19 HR300505 2. Geocushion: The geocushion will be a 32 oz. geotextile placed over the 16 oz. geotextile. The geocushion rolls will be laid with a 6" overlap per roll. The seams will be sewn per the requirements of the contract documents. 3. Gabion Mats and Gabion Baskets: The gabion mat represents the top layer of the protective cover. The mat will be installed on top of the 32 oz. geocushion. The mats will be pre-assembled on the site within the material laydown area on the Plant property and transported to the installation location. The initial layout of the gabion baskets will be a Licensed Maryland Surveyor according to the control and locations presented in the Approved 100% Design. Additional on-going layout required will be performed by a combination of the Surveyor and/or CEV personnel. The mats will be set into place and secured per the requirements of the approved 100% Design. The bottom of each mat to be placed over the barrier layer will be visually inspected to ensure that mesh barbs are turned up or trimmed to avoid puncture of the geomembrane. The mats (and Baskets) will be secured to each other by means of PVC coated steel 'Hog' Rings. As an additional precautionary measure, CEV will place 12" wide strips of a mat material under the side edges of each basket. This will aid in the protection of the geomembrane below. The mats will be anchored to the concrete walls in the following fashion; the 16 oz. geotextile previously installed will be pulled up tight to the concrete wall, the mat will be placed up against the geotextile/wall. The mat will be secured to the wall drilling hole for 3/8" dia anchor bolt at 12" on centers, installing the bolts, placing a steel batten strip 3/8" thick by 6" wide by 2'-10" long over the bolts thus anchoring the mat to the wall. Gabion baskets to be used in the wall construction will be assembled and installed in a similar fashion as the gabion mats. The baskets will be erected on the Plant property, transported to the intended location, secured to other baskets/mats per the requirements of the contract documents. The gabion stone will be placed in accordance to the requirements of the approved 100% Design. CEV will place the gabion stone by several methods; mechanical conveyor, Rubber Tired Loader and in the hard to reach areas the stone will be hand placed. The mechanical conveyor is the most efficient means of loading, the variable controls of the speed of the conveyor can be such that it can be slowed down to such a pace as to install one stone at a time if necessary. This control will Galaxy/Spectron Remedial Action Conti Environmental, Inc. Removal Action Execution Plan(Draft) 05/01/98 Page 20 AR300506 ensure that the underlying fabrics and geomembranes are not damaged during the loading operations. The conveyor will be set off to the side and can be extended to reach to most lengths required by this project.. CEV has extensive experience in the installation and loading of gabion baskets and mats and every effort will be made to maintain the integrity of the lower materials. The grout strips within the gabion mats will be constructed in a continuous fashion during the gabion work, the gabion mats will be installed, stone placed and by use of a small grout pump, the grout will be placed throughout the stone filling all voids. The grouting operation will be carefully performed in order to keep area clean of excessive grout. See Section XIV for detail regarding the Habitat Restoration including the placement of planting soil and/or sand within the gabion mats. XIII. Habitat Restoration Habitat restoration work will involve the re-establishment of the benthic and riparian habitat of Little Elk Creek and the surrounding areas to be impacted by the removal Action. CEV will perform the following operations in an effort to satisfy the requirements of the contract documents. Prior to restoration activities, CEV will remove all foreign materials and loose objects from the gabion surfaces or the area of Zone A. Zone A activities will include the preparation of the ground surface to a depth of 3" in the soil. This will be accomplished by a combination of disking and hand raking where machinery is inaccessible. The final grade of Zone A surface will conform to the grades within the contract documents. Zone D sand fill substrate will be constructed after Zone A but before Zones B & C, which receive the planting soil substrates. Fill sand will be introduced over the channel bottom to the limits of the contract documents. The sand will be mixed in with the gabion stone prior to placement in the baskets. The balance of sand necessary to fill the voids per the Approved 100% Design will be installed by a small combination rubber tire machine and washed in with the clean upstream water within the 5000 Gallon on-site tank. The water used for this operation and the sediment encountered will be collected in the proposed sedimentation trap located adjacent to the downstream dam. As stated in the Erosion and Sediment Galaxy/Spectron Remedial Action Conti Environmental, Inc. Removal Action Execution Plan(Draft) ' 05/01/98 Page 21 RR300507 Control Plan, accumulated sediment will be cleaned from the sedimentation trap and incorporated into the work. Zones B & C substrates will be constructed after Zones A & D have been completed. Areas of gabion mat extending from the water side edge of Zone C construction to the uphill end of the gabion structure bordering Zone A will receive a secondary fill of Planting Soil. The Planting Soil will be installed per the requirements of the contract documents. The soil will be premixed with the gabion stone on-site prior to placement within the gabion baskets. SF mat will be installed on the inside of all exposed outside faces of gabions. The SF mat will be secured per the requirements of the contract documents. Zone C Bank construction will include the installation of the Biolog system. The biologs will be installed with wire tie-downs, Planting Soil placed to top of biolog on the land side. This soil backfill will be placed by PC 220 excavator reaching over and placing to ensure no equipment on top of the biologs. The CF mat will then be placed over the biolog and the planting soil and secured down per the requirements of the contract documents. Installation of Plants are not part of this contract. Location of the Boulder Islands will be at the direction of the CQA Monitor. The installation process is as follows; place boulder with a maximum 6' in width with long axis parallel to flow. The boulders will be placed with the PC-220 or PC-400 Excavators. 3' diameter sack gabions will be installed around the upstream side end of the boulder as per the contract documents. The sack gabions will be secured with underlying gabion mats via wire ties. The double biolog system within the Boulder Islands will be installed per the detail on Plan Sheet No. 17 of the contract documents. The installation methodology will be of similar fashion as the biologs within Zone C banks. The Riffle Zones locations will be at the direction of the CQA Monitor. The Riffle Zones will consist of stones placed in rows parallel with the flow and intersecting rows perpendicular to the flow creating a braided pattern. The stones will be between 12" and 48" in diameter and situated from largest to smallest heading downstream. Galaxy/Spectron Remedial Action Conti Environmental, Inc. Removal Action Execution Plan(Draft) 05/01/98 Page 22 RR300508 XIV. Demobilization Upon completion of all closure activities, the site will be demobilized. All decontamination liquids and waste materials will be fully characterized and disposed of off-site as appropriate. The storage and tool containers will be removed and miscellaneous debris taken off site. Gaiaxy/Spectron Remedial Action Conti Environmental, Inc. Removal Action Execution Plan(Draft) 05/01/98 Page 23 AR300509 XV. Traffic Control Plan CEV will initiate a Traffic Control Plan for all material and supply deliveries, equipment mobilization and demobilization and all other activities involving the surrounding public roads to assure that safety of the nearby residents and the on- site work force are not compromised. Material deliveries, most notably, trucks delivering stone products to the job present the greatest challenge in maintaining a safe, functional work area. The main concern is the volume of trucks which will be traveling along either Providence Road or Little Elk Creek Road enroute to the site. CEV is sensitive to the residents and cognizant of the fact there are children in the area and will take all necessary precautions to ensure their safety. CEV will schedule a meeting at the individual quarries supplying stone products for the project. The meeting(s) will be to stress the importance of safe professional driving by the employees of the quarries or by any of the quarries subcontractors (independent truckers). Disciplinary actions against the driver and the quarry will be discussed if there are any violations by the drivers. There will be a zero tolerance for violations. If a driver does not obey the speed limit, yielding to traffic, abusive language or any other act not acceptable to CEV he or she will be immediately removed from the site and told not to return. The quarry will be contacted with the name of the driver, truck number and an explanation of the violation. The quarry will then have to supply another driver to fill the void of the dismissed truck. CEV will supply a 'spotter' positioned on-site to direct the trucks to the proper location to dump their loads. The spotter(s) is responsible to manage all trucks on-site to ensure safe movement and dumping operations on-site. A site vicinity map will be given to each supplier of material required to deliver to the site The map will depict the truck route to be used to enter the site. The spotter will also be responsible to move construction traffic over the Providence Road Bridge when necessary. CEV will take every precaution necessary to ensure the safety of the residents and the on-site personnel during traffic movement operations. Galaxy/Speclron Remedial Action Conti Environmental, Inc. Removal Action Execution Plan(Draft) 05/01/98 Page 24 AR3005IO 2 R1H HOLLOW-CORE f&WfSS^E^;- PRE-STRESSABLE * POSITIVE CONE EXPANSION SHELL THRUST MEETS ASTM A-615 'RING DEFORMATION PATTERN Through years of development Williams has produced and patented ihe Pre- stressable, Hollow-Core, Groutatjle Spin-Lock Rock Bolting Systems. The "hollow-core" allows the bolt to always be grouted from the lowest gravita- tional point (Fig. A), in an up-boning situation, the grout Is pumped In through the plastic grout tube and begins to fill the drill hole from the plate. The grout rises until the entire hole is filled and the grout returns through the hollow bar. In down grouting situations, the grout is pumped through the hollow bar and starts at the bottom ot ;jie hole. It rises and returns through the de-air tube when the hole Is filled. Improperly or incomplete grouted bolts are subjected to relaxation and corrosion. Pre-measured capsule systems cannot properly account for u nknown fissu res and voids and often leave the bolt vulnerable to deterioration. The Williams Hollow-Core Grouting System spreads grout through the rock fissures creating a completely protected monolithic section including rock, grout and bolt. Full installation procedures can be found on pagss T (Fig. A) WHIia/hs Hollaw-Cora anchors ———:————'—*• .i*ltl.;——,' . 'TV) JT7T TT".- -———————————'——— allow for fun growl encapsulation in up and STRUQTLJff/VL PROPERTIES , down bolting applications and allows grout Yield Stress Ultimate Stress . Bprtgalton in 2" Reduction of Area flow from the lowest gravitational poim 70 KS! 'Vo'kSI." '"-" R1H WILLIAMS LOW GRADE HOLLOW-CORE PRE-STRESSABLE ROCK & CONCRETE ANCHOR ASTM A 615 DEFORMATION PATTERN NET THREADS THRU PERM. THREADS *>.' 2.427 100,000 IDS. (51mm) (444.9 WU) Note: (1) Care should be taken to drill a slraiont Property sized hole. (2) A (unction of strata strength. Mom torau* roav be reeruirod on lono bolts or in special rock condrtioiK. Consutt your Wiffiams Representatta for more soecffic dffeBs. (3) Strew to rtcsiretf tensH? low using a hollow rim hytouflc pck. Consutt yow Wiltens Representative. (4) WILLIAMS reserves DM right to ship fufl tefigtli or coupled units ss necessary, (5) On special orders, R1H grade may be heat treated tor cold weather environment fer minimum Ctiarpy vikws ot M tl-1bs. at -20T {3CTC). (8) Ultimate simple shear strengths are appnnirmttty .751 tht uttimzte tensile strengths. Designer! should pravid* adequate safety factor* for «Ie snexr rtn;ngth$ bVed on condiGons ot use. Inconsistencies in rock front srw to sire antj evsn from hole to hoie may affect anchor performances. Fissures, voids, seams, rock psi, drillirtQ through clay or bentonite snd director or balding planes are all possible variables, Sieutt piodlons occur, consult VVifliams for troubleshootlno techniques. UJILLIflfTiS i6WEl£Ol9l 'ON ON3 SUVmiM 0311 86-1 "SPIN- LOCK"0 ROCK BOLTS GROUTING • PERMANENT KEYHOLE PLATE Because the "SPIN-LOCK"* head assembly provides 300° perimeter expansion anchorage (Rg. B) and develops the BOUNDRY DAM-C11 V Of SEAtTLE full strength of the rod, the hollow-core rock bolt may be pre- (Underground Powerhouse) Design - Bechtei Corp stressed to the desired load and tested prior to gouting. Prime Contractor • Mannix S.G.S, (Fig. B) Williams "Spin-Lock" head assem bites give a 300° perimeter expansion anchor- age. For more Information on "Spin-Lock" head assembfies, turn TO page 20. STRUCTURAL PROPERTIES Yield Stress Ultimate Stress Elongation In 2" Reduction of Area 91 KSI 124 KSI 15% 40% R1H HIGH GRADE HOLLOW-CORE PRE-STRCSSABLE fiOCK & CONCRETE ANCHOR ASTM A 615 OEPORMATiON PATTERN .. NET TOROU^FTXB. • " DIM ' AREA MAXIMUM ULTIMATE TYPE PART THREADS THRU' b.fSfGN 10 ' WORKING 'jTflEHGtti ROW TYPE,1'' HOLE HEAD . .to ON NUT PERI*. THREADS AT soy. b LllAO TO EXPAND . FOB IN.* ilLTMflffl SHR.M2) TENSfOK A 13 R1H03A13 Hard 4M«ftifn A 14 250 (Do R1H06A14 r-a .536 33.000 LR 117,000 LBS. 66,OdOLBS. Medium & Weak l-3M"-(4 •UJILLIflfnS 03(1 86-1 - 30'd 'ON dHOO 9N3 "SPIN-LOCK" ROCK BOLT INSTALLATION PROCEDURE "T^O;^:VV^^J.^ STEP#1 DRILLING USE STANDARD ROTARY PERCUSSION EQUIPMENT N In down bolting situations, drill the holes to extend 10" to 16" beyond the length of the rock bolr to allow for segments dropping into the bottom of the hole. Overhead rock drilling or shallow concrete applications require only minimum clear- ance, 1" to 3" of overdrlll. Care should be taken to Insure an accurate and straight hole. Anchor installation should DOWN BOLTING occur within 24 hours of open- SITUATIONS ing drill hole. Before inserting REQUIRE rock bolt, probe hole to insure it DRILLING is clear to proper depth. Use a HOLES 10- blow pipe to remove mud, day 70 16"BfeYONO and debris when necessary. If THE LENGTH rock ROD value is 50-70%, OF THE ROOK BOLT. water testing the hole is recom- mended before proceeding (see page 32.) Install test anchors prior to drilling all of DRILL the rock anchor holes. HOLE CHURCHILL FALLS HYDROELECTfltC OEVEIX3PMENT Owner - Churchill Palls (Labrador) Corp. Design: Acres Canadian Beehtsl Contractor - Churchill Contractors ." f'"*1? 'r~l£;r7v;;>L~ STEP #2 BOLT PLACEMENT WILLIAMS SETTING Place ftut, washer, = U'TOOL and plate on rock bolt HEAVY DOTY and lower bolt into HEX NUT AND jj ' WILLIAMS HARDENED KEYHOLE drill hole with thrust- STEEL WASHER ring, malleable shelf. PLATE and cone set in position on the inner threaded portion of the bolt. If rock boll becomes ROCK BOLT BEING INSERTED INTO stuck because of a crooked HOLE hole, lock two nuts on the end of ih« baft and tap bolt Into p(3£e with a sledge hammer or WILLIAMS air hammer. A jumbo drilling HOLLOW rig can be used to push large ROCK diameter bolts Into the hole. BOLT For rock bolts longer than 20', especially In poor rock or THRUST RING sh«l« where drill holes rend to MALLEABLE drift or collapse, an oversize drill hole can be used within 4 to 6 ft. of anchor area. This will CONE expedite installation. Care should be used to insure cor- rect drill hole size however In the anchor area. Bolt should hang by the nut against the "BOUNDARY DAM" POND, OREILLE RIVER bearing plate until set. Department of Lighting, City of Seattle Design; Sechtel-LeedshJfl. Prime Contractor • Mannlx s.G.S. 16 dHOO ON3 swmiM etr^i d3M 96-i -inr 90'd i6fr6£l£0l9l 'ON XVJ "SPIN-LOCK" ROCK BOLT INSTALLATION PROCEDURE ^;^ STEP #3 SETTING THE ANCHOR Install setting 1661 Oh threaded end. The setting QUICK SPIN US(NQ (MPACTGUN tool must be turned oh to its "full engagement (to internal stop) prior to contacting the hex nut. Set WILLIAMS FfTTtNG ADAPTER the expansion anchor by torquing ttte rod T6 the FOR IMPACT TOOL OR TORQUE WRENCH-'" required torque (see Spin-Lock Rockbott Charts). This is done by turning the setting tool in a clock- wise direction using either a pneumatic or manual Il" j#YT'!-K* T9F SETTING u^^j torque wrench (refer to Accessories, pg. S6), This ~'HWi- IMPACT TOOL TOOL -^tf action rnigrates the cone Into shelf, thus «JS expanding the anchor. The bolt can be sec either 2-3" OF THREAD with or without the steel bearing plate in place, and with any desired amount 6f thread extending beyond the hex nut. After setting the boft remove the two piece getting tool by separating the top nut from the body. TfiZ-12 _^ PNEUMATIC TORQUE WRENCH 5s •RECOMMENDED- MULTIPLlE;flT8Zl3 TORQUE WHENCH TSZ AUBURN-WASHINGTON BRIDGE Contractor: Burnham Construction KX3.-& t^K1- NOTE: When salting or t&nslcrcing rock bolts by use of an impact gun, a random check of torque usfng a calibrated hand torque wrench or hydrautfc j$ck should be done to Insure the Impact gun continues delivering (ho specified torque. STEP #4A TESTING THE ANCHOR BOLT PLATE WASHER NOT, METHOD A Tenstonlng with a Test Jack .^HOLLOW CORE Test the rock bolt by jacking the rock bolt to ihe required tension (usually Va of the ultimate ••^HYDRAULIC JACK strength). Once the bolt is tested, it Is very easily pretenstoned. This pretensioning is accom- SOUP HfGH-STHENOT( plished by using a wrench to tighten the rock bolt nut to transfer the test load from the jack EXTENSION BAR to the rock bolt. The needle on the pump gauge will drop slightly to indicate less tension on HfGH-STRENGTH the jack and frame only. Release jack pressure and remove jack, frame extension rod and COUPLING USE WRENCH coupling. TO TIGHTEN NUT HERE WHEN HELPFUL HINTS: REQUIRED If outward migration of bolt is noticed during tensloning, check to make suffe that tension Is increasing TENSION IS on pump gauge. REACHED A. If tension is increasing on gauge the outward migration is indicating the anchor is further expand- ing. If migration Is excessive, it can be minimized or avoided by applying more torque to set me anchor. (For maximum torque allowed check wfth your Williams representative. in B, if tension is not increasing on gauge this outward migration may be anchor slippage. This indicates CD That more torque is required to set rhe anchor or that a larger expansion head may be required. CD ^ (Check with your Williams representarfve.) CO 1. Make sure final torque is being applied in a continuous turn fashion using T82 or T8Z12 wrench. or 2. Check to see that the proper drill bit size was used in drilling the hole. 17 SrIVmifl STEP #5 GROUTING (WITH WILLIAMS HOLLOW-CORE BOLT) FttOM GROUT PUMP GROUT TUBE WILLIAMS GROUT TUBE ADAPTER METHOD A DE-AIR Down or Horizontal Grouting Screw grout tube adapter on to rock boft. Blow air through hollow core to assure system is clear- Pump Wil-X- Cement Grout through hollow core of boft until a continuous flow of grout is seen coming out of the de;air tube. This indicates that all air has been removed from drill hole and all cracks, and fissures in the rock are Ml of grout. Remove grout tube adapter. Trie drill hole has been fully grouted and all standing water or air has been removed. OU> HICKORY LOCK and Contractors - U.S. Army Corps of Engineers WHEN GROUTING IN WATER USE THE SAME PROCEDURES OUTLINED ABOVE. By utilizing Williams Pre-stressed Grourable Hollow-Core Rock Bolts, grout is forced into areas in back of the anchorage, as well as into all porous rock-seams, fracture zones, and voids In the area of the drill-hole. Only Williams pre- stressed patented Hollow Bar Anchor Jn combination with special plates for grouting after pre-stresslng, gives external proof (return grout Wow) of a job well done. METHOD B Up Grouting (Using standard grout mix or Poly Grout) For UP-GROUTING, inject grout at the pressure required to offset static head. Grout should be forced through the short tube which will be placed at the lower level of the hole until it returns through the de-air hole in the end of the bar. Discharge of pure grout in a steady stream through the de-air hole Is positive OR DENSE EXPANSIVE proof that the entire hole is filled and FOAM entire area of the bolt including seams fs well grouted. Plug end of bolt and continue pumping briefly to force grout to end of hole. Theft block the grout tube. RETURN NOTE: If WihX-Cement Grout Is not used, please refer to pg. 39 for alter- nate grout specifications, pg. 12 for Poly Grout applications, or pg. 8 tor thixotropic grout installation. FROM GROUT PUMP UJILLIflfTlS 19 «3 /.6fr6£l£0l9! 'ON 80 'd