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Fairways-SP 930716 TRENCH SAFETY SPECIFICATIONS FOR THE FAIRWAYS AT RIVERCHASE CITY OF COPPELL, TEXAS Prepared for C. W. YOUNG CONSTRUCTION, INC. TREN-TECH COMPANY TRENCH ,.~AI~lZ*I'Y TECHNOLOGY 2560 ELECTRONIC LANE #104 DALLAS, TEXAS I have reviewed this Tranch Safety Plan ~d find that its recommandations and procedures conform to OSHA guidelines md regulations. The calculalions herein are consistmt with ganerally accepted enghaeering practice. REGISTERED PROFESSIONAL ENGINEER DATE 1.0 DESIGN ASSUMPTIONS 1.1 General. These specifications cover the basic requirements for shoring and/or sloping of excavations for the installation of WATER, STORM DRAIN and SANITARY SEWER to serve the FAIRWAYS AT RIVERCHASE in the CITY of COPPELL, TEXAS. 1.2 This specification addresses the safety of workers in a trench excavation and does not, in any way relieve the Contractor of his responsibility and liability to ensure the safety of the project and workers. 1.3 It is not the intent of these specifications to specify every detail and procedure of the trenching/shoring operations; nevertheless, they shall conform to the high standards of engineering and of safe trench excavation. 1.4 The personnel protection systems shown in these specifications have been designed based on information obtained from the project drawings. 1.5 The personnel protection systems shown in these specifications have been designed based on the plans and specifications. In accordance with Revised OSHA (Appendix A to Subpart P effective March 2,1990), the Contractor's "Competent Person" will conduct the required Soil Classification Tests. If soils other than those previously identified are found, this specification will be revised. During construction, the Contractors "Competent Person" will monitor the soil classification as required by OSHA 1926. 1.6 Contractor shall be responsible for selecting the appropriate safety system option shown in these specifications, depending on trench depth and soil conditions. 1.7 The protection of existing structures and utilities which may be affected by these trench excavations is beyond the scope of this report (See Sect.4.2) 1.8 The Comractor must identify a "Competent Person" in the Contractors firm responsible for performing inspections of the excavations to ensure that expected subsurface conditions are present. NOTE-This person must be "Competent" as described in OSHA 1926.650(b). 1.9 h is the Contractors responsibility to ensure that all excavation work and site conditions are within the regulations as established by OSHA. Any property damage or bodily injury (including death) arising from the use of these specifications, from the Contractors negligence in performance of contract work, or from Owners failure to note exceptions to these specifications shall remain the sole responsibility and liability of the contractor. 2.0 DEFINITIONS 2.1 All definitions of section 1926.653 of Subpart P, Part 1926, of the Code of Federal Regulations shall be by reference an integral part of this section. 2.2 2.3 "Sealing Engineer"- The engineer whose Texas seal is affixed to these specifications. "The Contractor"-The contractor respons~le to the owner for the excavation work described herein. 2.4 "Competent" as described in OSHA 1926.650(b). 3.0 APPLICABLE CODES AND STANDARDS 3.1 The Contractor shall perform all shoring work under this contract in accordance with all applicable codes and standard safety requirements and regulations including: 3.1.1 OSHA 2207, Construction Industry Standards (Part 1926, Occupational Safety and Health Standards) 3.1.2 AISC Code of Standard Practice. 3.1.3 AISC Specifications of the design, fabrication, and erection of steel buildings 3.1.4 AITC Timber Construction Manual 3.1.5 AWS DI.1 Structural Welding Code 3.1.6 The Uniform Building Code 3.1.7 OSHA 2226 3.2 The latest edition (including supplements and revisions) of the above publications in effect or promulgated at the time of the bid shall apply. Equipment fabricated to codes and standards in effect at time of bid but later revised shall be acceptable provided such revisions are not required by law. 2 4.0 SHORING/SLOPING REQUIKEMENTS 4.1 Description. This section covers the technical requirements of the trenching/shoring work. 4.2 Existing Structures. Where existing buildings, other utilities, streets, highways, or other structures are in close proximity to the trench, or may otherwise be affected by the proposed trenching operation, the Contractor shall provide adequate protection by the use of sheeting and shoring to protect the structure, street, or highway from possible damage. In the case of utilities, the Contractor may elect to remove the utility, provided that the removal and subsequent replacement meet with the approval of the engineer, the ut'flity owner, or whoever has jmisdiction of the structure. In all cases, it shall be the responsfoility of the Contractor to protect public and private property and any person or persons who might, as a result of the Contractors work, be injured. 4.3 General Trenching and Shoring Requirements. The Contractor shall be solely responsible for trench safety provisions meeting the applicable requirements of the United States Department of Labor-Occupational Safety and Health Administration, including subpart P, Part 1926, of the Code of Federal Regulations. All trenching operations and procedure shall also conform to the requirements listed in this specification. 4.3.1 The requirements of sections 1926.650 and 1926.651 of Subpart P, Part 1926, of the Code of Federal Reg~j!ations shall be by reference an integral part of this section. 4.4 Requirements Prior to Excavation Activities 4.4.1 Known underground installations are shown on the site plans. It is the Contractor's responsibility to verify exact locations in the field. 4.4.2 Before any individual enters an excavation, the excavation will be inspected by a "Competent Person" to ensure that trench excavation has been performed according to this specification and OSHA requirements and to ensure that no anomalies are observed which may effect the safety of the trench project. Note-This person must be "Competent" as described in OSHA 1926.650(b). 4.5 Requirements During Excavation Activities. 4.5.1 During excavation, the exact location of existing underground installations shall be determined by the Contractor, and when uncovered, proper precautions and supports shall be provided so as not to cause a hazard to the workmen or the project. 4.5.2 Daily inspections of the excavations shall be made by the Competent Person". ffthere is evidence of possible cave-ins or slides, all work in the excavation shall cease until the necessary precautions have been taken to ensure the safety of the workmen and the trench. Note-This person must be "Competent" as described in OSHA 1926.650. Excavations shall be inspected alter every rainstorm or other hazard-increasing occurrence to ensure safety of the workmen and the trench. 4.5.3 Excavated material shall be stockpiled a distance away from the trench, so as not to affect the trench stability. The Contractor's means and methods will determine the distance. As a mininmm to protect the workmen from falling debris, the toe of the stockpiled soil shall be no closer than two(2) feet from the edge of the excavation. 4.5.4 All precautions must be made to prevent surface water from entering the trench excavation. Adequate drainage must be provided in the area adjacent to the excavation. 4.5.5 Operation of heavy equipment adjacent to the edge of the trench may cause instability. The Contractor is responsible for the means and methods of excavation, and therefore, for loads imposed on the trench excavation and shoring design. 4.5.6 The Contractor must take precautions to protect the face of the excavation from exposure to excessive drying, water, or freezing. 4.5.7 Water shall not be permitted to stand in the bottom of the trench and suction pumps of adequate capacity shall be installed to ensure that such standing water is removed. 4.5.8 The Contractor shall provide a positive means of ensuring that hydrostatic pressure does not build up behind the shoring or shields. 4 4.5.9 4.5.10 4.5.11 4.5.12 4.5.13 4.5.14 4.5.15 If a condition requiring the use of a different method of shoring is encountered, this specification will be revised. Remove shoring units from bottom to top as backfilling proceeds. When backfill is within five(5) feet ofthe top ofthe trench, all shoring may be removed, unless the trench conditions indicate a hazard. No person shall be exposed to the lower portion of the trench at~er shoring has been removed. Additional shoring of larger sizes may be installed. Ladders or other adequate means of exit must be provided and located so as to require no more than twenty-frye(25) feet of lateral travel When two(2) trenches intersect, both trenches must be protected to a distance of not less that the depth of the deepest trench. SECTION 5.0 SITE SPECIFIC EXCAVATIONS AND SHORING SPECIFICATIONS FOR SANITARY SEWER WATER LINE AND STORM SEWER 5.1 EXCAVATIONS SPECIFIC TO THIS WORK STORM SEWER LINE "A" LOCATION MAX.DEPTH OPTION -0+42 6.0 I, II -0+42 TO 3+20 11.0 I, II 3+20 TO 8+03 11.0 I, II 8+03 TO 8+33 10.5 I, II 8+33 TO 8+77.77 9.0 I, II 8+77.77 5.0 I, II STORM SEWER LINE "A" LATERALS MAX.DEPTH LOCATION OPTION 4+70.05 9.5 I, n, m 7+98.29 10.0 I, II 8+27.69 9.5 I, II NOTES CONST HDWL INSTALL 42" RCP INSTALL 30" RCP INSTALL 24" RCP INSTALL 18" RCP CONST INLET NOTES INSTALL 18" RCP INSTALL 18" RCP INSTALL 18" RCP STORM SEWER LINE "A- 1" LOCATION MAX.DEPTH 0+00 10.0 0+00 TO 0+72 10.0 0+72 TO 3+75 5.5 3+75 TO 4+07.10 4.5 4+07.10 5.0 STORM SEWER LINE "A-I" LATERALS LOCATION MAX.DEPTH 0+66.90 6.0 3+70.66 4.5 OPTION I, ii I, II I, II, III I, IL Ill OPTION I, II, IH I, H, m NOTES CONN TO 42" RCP INSTALL 30" RCP INSTALL 21" RCP INSTALL 18" RCP CONST INLET NOTES INSTALL 21" RCP INSTALL 18" RCP STORM SEWER LINE "B" LOCATION MAX.DEPTH OPTION 0+00 4.5 I, II 0+00 TO 2+16 7.5 I, II 2+16 TO 2+58 7.0 I, II 2+58 TO 4+56 7.0 I, II 4+56 TO 4+85.74 6.0 I, II 4+85.74 7.0 I, II STORM SEWER LINE "B" LATERALS MAX.DEPTH LOCATION 2+53.07 6.0 4+52.75 6.5 OPTION I, IL HI i,u,m NOTES CONST HDWL INSTALL 36" RCP INSTALL 30" RCP INSTALL 27" RCP INSTALL 21" RCP CONST INLET NOTES INSTALL 18" RCP INSTALL 18" RCP STORM SEWER LINE "B-I" LOCATION MAX.DEPTH 0+00 6.0 0+00 TO 1+69.74 6.0 1+69.74 5.5 OPTION I, IL RI i,n,m NOTES CONN TO 36" RCP INSTALL 18" RCP CONST INLET STORM SEWER LINE "B-2" LOCATION MAX.DEPTH 0+00 6.0 0+00 TO 0+70.88 6.0 0+70.88 5.0 OPTION I, Ikm i,n NOTES CONN TO 36" RCP INSTALL 18" RCP CONST INLET STORM SEWER LINE "B-2" LATERALS LOCATION MAX.DEPTH 0+41.01 5.0 OPTION NOTES INSTALL 18" RCP STORM SEWER LINE "C" LOCATION MAX.DEPTH 0+00 4.5 0+00 TO 1+65 12.0 1+65 TO 2+65 11.5 2+65 TO 7+31.18 8.5 7+31.18 5.5 STORM SEWER LINE "C" LATERAL LOCATION 2+59.91 9.0 OPTION I, II I, II I, II I, II, HI I, II OPTION NOTES CONST HDWL INSTALL 33" RCP INSTALL 30" RCP INSTALL 18" RCP CONST INLET NOTES INSTALL 18" RCP STORM SEWER LINE "C-I" LOCATION MAX.DEPTH OPTION 0+00 11.0 I, II 0+00 TO 1+06.83 11.0 I, H 1+06.83 6.0 I, 1I NOTES CONN TO 33" RCP INSTALL 18" RCP CONST INLET SANITARY SEWER LINE "A" LOCATION MAX.DEPTH OPTION 0+00 19.0 I, II 0+00 TO 0+94.66 17.0 I, II 0+94.66 18.0 I, II 0+94.66 TO 4+61.01 17.0 I, II 4+61.01 14.0 I, II 4+61.01 TO 7+70.44 13.0 I, II 7+70.44 10.5 I, II NOTES CONST MH INSTALL 10" SS CONST MH INSTALL 10" SS CONST MH INSTALL 10" SS CONST MH SANITARY SEWER LINE '°B" LOCATION MAX.DEPTH OPTION 0+00 13.0 I, II 0+00 TO 2+84.24 13.0 I, II 2+84.24 12.5 I, II 2+84.24 TO 5+88.35 12.0 I, II 5+88.35 9.0 I, II NOTES CONN TO MH INSTALL 8" SS CONST Mit INSTALL 8" SS CONST MH SANITARY SEWER LINE "C" LOCATION MAX.DEPTH OPTION 0+00 9.0 I, II 0+00 TO 2+65.69 9.0 I, II 2+65.69 7.5 I, II 2+65.69 TO 5+23.75 6.5 I, II 5+23.75 6.0 I, II NOTES CONN TO MH INSTALL 8" SS CONST MH INSTALL 8" SS CONST MH SANITARY SEWER LINE "D" LOCATION MAX.DEPTH OPTION 0+00 9.5 I, II 0+00 TO 3+13.18 9.0 I, II 3+13.18 9.5 I, II 3+13.18 TO 6+53.38 8.5 I, 11, III 6+53.38 7.5 I, II 6+53.38 TO 7+67.84 6.5 I, I~ IH 7+67.84 7.0 I, II 7+67.84 TO 9+93.84 6.0 I, II, IH 9+93.84 6.5 I, II NOTES CONN' TO MH INSTALL 8" SS CONST MH INSTALL 8" SS CONST MH INSTALL 8" SS CONST MH INSTALL 8" SS CONST MH SANITARY SEWER LINE "E" LOCATION MAX.DEPTH OPTION 0+00 9.5 I, II 0+00 TO 2+65.66 9.0 I, II, IH 2+65.66 9.5 I, II 2+65.66 TO 4+76.47 8.5 I, II, IH 4+76.47 8.0 I, II NOTES CONN TO MH INSTALL 8" SS CONST MI{ INSTALL 8" SS CONST MH SANITARY SEWER LINE "F" LOCATION MAX.DEPTH OPTION 0+00 8.0 I, II 0+00 TO 1+59.45 8.0 I, II, III 1+59.45 8.5 I, II 1+59.45 TO 6+04.12 7.5 I, II, IH 6+04.12 6.5 I, II 6+04.12 TO 7+85.81 5.5 I, II, IH 7+85.81 6.5 I, II NOTES CONN TO MH INSTALL 8" SS CONST MH INSTALL 8" SS CONST MH INSTALL 8" SS CONST MI1 lO SANITARY SEWER LINE "G" LOCATION MAX.DEPTH OPTION NOTES 0+00 8.0 I, II, III CONN TO MH 0+00 TO 2+47.80 8.0 I, II, III INSTALL 8" SS 2+47.80 5.0 I, II CONST MH SANITARY SEWER LINE "H" LOCATION MAX.DEPTH OPTION NOTES 0+00 8.5 I, II, m CONN TO MH 0+00 TO 3+69.33 7.0 I, Il, IH INSTALL 8" SS 3+69.33 7.5 I, II CONST MH 3+69.33 TO 4+97.04 7.0 I, II, IH INSTALL 8" SS 4+97.04 6.5 I, II CONST MH WATER LINES & APPURTANENCES Water lines not profiled. Trenches less than five(5) feet in depth may be cut vertical if there is no evidence of raveling or caving(OSHA 1926.651 ). Contractogs "Competent Person" will determine soil stability and use Option I, II or IH if unstable conditions exist. 11 5.2 SHORING ALTERNATIVES FOR THIS WORK 5.2.1 Trenches more than five(5) deep shall be shored, laid back to a stable slope, or some other equivalent means of protection shall be provided where employees may be exposed to moving ground or cave-ins. Trenches less than five(5) feet in depth shall also be effectively protected when examination of ground indicates hazardous ground movement may be expected. The Contractor will have options for providing such protection. 5.2.2 Lateral Earth Pressure P= a uniformly distributed lateral soil pressure, in lbs./f~2 We= Effective Soil Weight, pcffUse 45 pcfrype "B" Soil) H= Depth of excavation t~om top of supported bank to bottom of excavation, in feet. Hq= Equivalent Height of Surcharge, in iL P=- We*(H+Hq) (Reference OSHA Rules and Regulations-Part 1926 of 29 CFR as amended by the Federal Register Voh~me 54, Number 209, dated October 31, 1989.) 5.2.3 5.2.4 5.2.5 Option I The Contractor can use Slope as shown in the Option I section of the specification. Applicable slopes may be obtained by either straight cut or benched method. Vertical cuts for the benched method shall not exceed four(4) feet. See Drawing Option I. Option H The Contractor can use a Trench Shield as shown in the Option H section of this specification. See Drawing Option H. Option In The Contractor can use Trench Shores as shown in the Option 1II Section oft}ds specification. See Drawing Option III. 12 Trench Safety Specifications Option I Slope V 2'O"minimum bench H single H/V-STEEPEST ALLOWABLE SLOPES H/V=3/4 to 1 In stiff clays less than 12' in height. H/V=I to 1 In stiff clays greater than 12' in height H/V= 1 1/2 to 1 In stiff silty clays H/V=2 to 1 In loose soils or fill material "Stable Rock" may be cut near vertical Contractor's "competent person" shall monitor and verify anticipated soil conditions as the excavation proceeds. The contractor may use the benched method of"slope" however horizontal and veritical cuts shall be as follows. 3/4:1 H=3 V=4 1:1 H=4 V=4 1 1/2:1 H=4 V=3 2:1 H=4 V=2 NOTES 1. All slopes assume a dewatered condition. 2. All slopes assume sufficient right-of-way exists. 3. All slopes should be flattened an additional .5' if an existing parallel utility line is located within the horizontal distance equal to the depth of the new utility excavation. 4. Single bench may be used in "Stiff Clays' only and shall not excced 3'6" in height. 5. No spoil or equipment shall be permitted nearer than 2'from the edge of the excavation. 6. Exposed existing utility lines are to be supported. Page Trench Safety Specifications Option II Trench Shield V H Sloped portions of the excavation shall begin 18" below the top of the trench shield and conform to guidelines outlined in Option I. Trench shields may be stacked according to manufacturer's guidelines for deeper excavations. Maximum 2'0" bench will be allowed in stiff clays only. MINIMUM SHIELD CAPACITY in "PSF" 950 as per tabulated data Trench Shields shall be inspected and free of structural defects that may impair their proper function. The trench shieM shall be used in accordance to manufacturer's guidelines and recommendations. Trench shields shall be installed so as to prevent lateral or other hazardous movement. Personell shall not be allowed in the trench shield when the shieM is being installed or removed from the excavation. Trench Safety Specifications Option III Shoring MaximumdepthofcutinType"A"or"B"soilshallbel4'O': If there ~s evidence of raveling or caving the contractor is required to use 1 1/8" plywood or 3/4" thick, 14ply, artic white birch(Finland form). Plywood is not considered a structural member, and its use is merely for the prevention of further raveling or caving of the / / ::/ Type"AT. soil 6'0" The contractor's "competent person" shall verify that the shores are in good working order. The hydraulic shores shall have a minimum worMng pressure of 750 psi. Excavated material will not be allowed nearer than 2'from the edge of the trench, and shall not exceed 4' ~n height. The contractor shall adhere to the shoring manufacturer's guidelines for use ~n trench excavations. Page