Excavation Trenching and Digging

PROCEDURE 440.1-57 Title: The most recent and official controlled hard copy version of this directive resides with NETL’s Directives Coordinator. An electronic version of the controlled directive has been placed on the NETL Intranet for employee use. Printed hard copies of this electronic version are considered noncontrolled documents. EXCAVATION, TRENCHING, AND DIGGING Bill Lowry, Safety Manager, ES&H Division, Office of Institutional and Business Operations Robert B. Reuther, Director, ES&H Division, Office of Institutional and Business Operations {signature} /s/ Robert B. Reuther Owner: Approving Official: Approval Date: Last Reviewed Date: Cancellation: 9/19/07 9/19/07 Procedure 440.1-37, Work Permits and Special Considerations, Attachment B TABLE OF CONTENTS 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. PURPOSE .....................................................................................................................................3 APPLICABILITY .........................................................................................................................3 PROCEDURE ...............................................................................................................................3 a. Permits...............................................................................................................................3 b. Inspections.........................................................................................................................4 c. General Requirements .......................................................................................................4 d. Hazardous Atmospheres....................................................................................................5 e. Rescue Equipment .............................................................................................................5 f. Stability of Adjacent Structures ........................................................................................6 g. Personal Protective Equipment .........................................................................................6 h. Fall Protection ...................................................................................................................6 i. Protective Systems (Shoring, Sloping, and Benching) .....................................................7 j. Subsurface Utilities ...........................................................................................................7 k. Operations .........................................................................................................................8 RESPONSIBILITIES....................................................................................................................9 a. Work Coordinators ............................................................................................................9 b. Competent Persons ............................................................................................................9 c. Organizations Performing the Work .................................................................................9 d. Designated ES&HD Representative................................................................................10 TRAINING..................................................................................................................................10 RECORD CONTROL.................................................................................................................11 REQUIREMENTS ......................................................................................................................11 REFERENCES............................................................................................................................11 DEFINITIONS ............................................................................................................................11 REVISION HISTORY ................................................................................................................14 The most recent and official controlled hard copy version of this directive resides with NETL’s Directives Coordinator. An electronic version of the controlled directive has been placed on the NETL Intranet for employee use. Printed hard copies of this electronic version are considered noncontrolled documents. Procedure 440.1-57, Excavation, Trenching, and Digging NETL Form 442.1-42/4, Digging Permit FORMS Attachment 1, Flow Chart of Permit Issuance ATTACHMENTS Page 2 of 14 Procedure 440.1-57, Excavation, Trenching, and Digging 1. PURPOSE a. To establish a permit system to control hazards related to excavation, trenching, and digging at NETL. It is not the intent of this document to detail how excavation should be conducted. The organization performing the excavation must do so according to the regulatory references listed in the procedure. The most recent and official controlled hard copy version of this directive resides with NETL’s Directives Coordinator. An electronic version of the controlled directive has been placed on the NETL Intranet for employee use. Printed hard copies of this electronic version are considered noncontrolled documents. 2. APPLICABILITY a. This procedure applies to all NETL employees and outside contractors that perform excavation, trenching, or digging as part of his/her responsibilities. 3. PROCEDURE a. Permits (1) A permit is required prior to: (a) (b) Entering a permit-required confined space. Digging greater than 6 inches below the surface, or adding more than 1 foot of fill, whether inside or outside a building. (2) The applicable permit must be filled out completely and signed by the designated ES&HD representative, the Site Operations representative, and the work supervisor prior to the beginning of work. The workers must understand the hazards and requirements listed on the permit. NETL Form 442.1-42/4, Digging Permit, can be found on the intranet (listed under Forms). Obtaining a permit does not relieve workers from adhering to other OSHA or NETL requirements. For example, lockout/tagout requirements apply regardless of whether or not a permit has been obtained. Permits shall be posted in the work area as long as work applicable to the permit is being performed. After the permitted work is finished, the permit shall be returned to the issuer; exception: when NETL on-site support contractors perform grounds maintenance activities, the permit shall be acceptable for the entire planting duration period of the year, and the designated DOE COR shall sign off on this permit and dictate any special circumstances required before the permit is issued. (3) (4) (5) (6) Page 3 of 14 Procedure 440.1-57, Excavation, Trenching, and Digging b. Inspections (1) Daily inspections of excavations and trenches shall be made by a designated competent person. If evidence of potential cave-in, slide, or water accumulation is found, all work in the excavation or trench must cease until the necessary precautions have been taken to safeguard workers. All excavations and trenches must be inspected by a designated competent person after every rainstorm or other hazard-increasing occurrence, and safeguards against slides and cave-ins shall be increased, if warranted. Refer to the tables in the relevant OSHA regulations as a reference guide for angle of repose and shoring techniques used in excavations and trenches. These tables show the minimum requirements. Added measures shall be taken if conditions warrant. Refer to Appendices A through F of 29 CFR 1926.652 for those tables and for other pertinent information such as soil classifications. The most recent and official controlled hard copy version of this directive resides with NETL’s Directives Coordinator. An electronic version of the controlled directive has been placed on the NETL Intranet for employee use. Printed hard copies of this electronic version are considered noncontrolled documents. (2) (3) c. General Requirements (1) Excavations 4 feet or more deep must be shored or sloped in an approved manner unless they are made entirely in stable rock. Sides of trenches above the 4-foot level may be sloped in lieu of shoring, but the slope shall not be steeper than 1-1/2 horizontal to 1 vertical. Each trench where workers are working 3 feet deep or more shall have ladders to provide safe exits. There shall be no more than 25 feet of lateral travel distance to the nearest ladder. Excavated or other material shall not be stored closer than 4 feet, if possible, and never closer than 2 feet from the edge of any excavation. Surface encumbrances that create a hazard shall be moved or supported, as necessary. The locations of any underground installations, such as sewer lines or electric lines, shall be determined before excavation. Site Operations shall be notified of the proposed work to establish the locations of utility installations before the start of an excavation. All such installations shall be appropriately identified for the safety of persons working nearby. Workers exposed to vehicular traffic shall be provided with, and be instructed to wear, warning vests marked with or made of reflecting or high-visibility material. No worker shall work beneath loads handled by lifting or digging equipment. (2) (3) (4) (5) (6) (7) Page 4 of 14 Procedure 440.1-57, Excavation, Trenching, and Digging (8) When mobile equipment operates adjacent to or approaches the edge of an excavation, a warning system such as barricades, hand or mechanical signals, or stop logs shall be used. Mobile equipment by its nature will change the condition of the soil, so soil reclassification must be conducted by the competent person. The use of water control and removal equipment shall be monitored by a competent person. Sloping or benching excavations greater than 20 feet deep shall be designed by a registered professional engineer. If the excavation is considered a high hazard task, the job task analysis procedure shall be followed in accordance with SARs procedures. To provide optimum protective safeguards of trenching operations, trench safety boxes for trenches up to 12 feet deep must be installed. The installation of the safety boxes shall be used within the limitations of the manufacture’s tabulated data. (9) The most recent and official controlled hard copy version of this directive resides with NETL’s Directives Coordinator. An electronic version of the controlled directive has been placed on the NETL Intranet for employee use. Printed hard copies of this electronic version are considered noncontrolled documents. (10) (11) (12) d. Hazardous Atmospheres (1) If the possibility exists for an excavation to have an oxygen-deficient atmosphere (less than 19.5 percent oxygen) or an atmosphere in excess of 10 percent of the lower flammable limit or lower explosive limit of a gas, atmospheric testing shall be conducted before workers enter the excavation. Refer to the NETL confined space entry and respiratory protection procedures for additional guidance. Proper respiratory equipment and ventilation shall be identified and provided for each excavation identified as containing a potentially hazardous atmosphere before workers enter the excavation. Atmospheric monitoring shall be conducted to ensure that atmospheres remain safe when controls are being used to reduce the level of contaminants. Refer to the NETL confined space entry and respiratory protection procedures for additional guidance. (2) (3) e. Rescue Equipment (1) When hazardous atmospheres exist, or are likely to develop, breathing apparatus and a safety harness and line or basket stretcher shall be readily available. This equipment shall be attended when in use. Workers entering bell-bottom pier holes or similar confined footing excavations shall be equipped with safety harnesses and individual lifelines. A designated, (2) Page 5 of 14 Procedure 440.1-57, Excavation, Trenching, and Digging properly trained worker shall be in attendance on the surface at all times while a worker is in an excavation of this type. f. Stability of Adjacent Structures (1) The most recent and official controlled hard copy version of this directive resides with NETL’s Directives Coordinator. An electronic version of the controlled directive has been placed on the NETL Intranet for employee use. Printed hard copies of this electronic version are considered noncontrolled documents. Support systems such as shoring or underpinning shall be provided for adjacent structures that may be endangered by excavation operations. Excavations below the level of the base or footing are normally not permitted unless: (a) (b) (c) A support system is used, The excavation is stable, and A registered professional engineer has determined that the structure is sufficiently removed from the excavation to avoid cave-ins. (2) g. Personal Protective Equipment (1) During performance of excavation, trenching, or digging activities, all workers shall have adequate personal protective equipment for the head, eyes, ears, respiratory organs, feet, hands, and other parts of the body as outlined below. (a) (b) Head protection shall be worn at all times. Appropriate eye protection shall be worn when there is danger of eye or face injury from physical, chemical, or radiant agents. If it is not feasible to reduce noise levels or noise exposure duration, approved hearing protective devices shall be provided and used. If engineering controls are inadequate or fail to control exposure to dust, vapors, and gases, respiratory protection shall be provided and used. Mechanical guards or protective devices shall be provided and used when hands and feet are exposed to potential injury from mechanical devices or other harmful agents. (c) (d) (e) h. Fall Protection (1) Walkways and bridges over excavations shall be provided with standard guardrails. Adequate barriers per OSHA 1926.500 requirements shall be provided at all excavations. All wells, pits, and shafts shall be barricaded or covered. Page 6 of 14 Procedure 440.1-57, Excavation, Trenching, and Digging (2) Upon completion of exploration and similar operations, all wells, pits, and shafts shall be completely backfilled. See the NETL Procedure 440.1-23, Fall Protection Program, for further fall protection requirements. (3) The most recent and official controlled hard copy version of this directive resides with NETL’s Directives Coordinator. An electronic version of the controlled directive has been placed on the NETL Intranet for employee use. Printed hard copies of this electronic version are considered noncontrolled documents. i. Protective Systems (Shoring, Sloping, and Benching) (1) Workers in excavations shall be protected by shoring, sloping, or benching. Exceptions to this requirement are: (a) (b) Excavations made entirely in stable rock. Excavations less than 4 feet deep and where examination of the ground by a competent person provides no indication of potential cave-in. (2) All protective systems for excavation sites shall be designed by a registered professional engineer when it is not feasible to attain required slope configurations in accordance with OSHA 1926.652(b)(1), (2), and (3). Sloping or benches greater than 20 feet deep shall be approved by a registered professional engineer. The OSHA regulation (29 CFR 1926, Subpart P) contains the requirements for soil classifications and sloping and benching to be used by registered engineers in determining sloping and benching for a particular excavation site. The registered professional engineer’s recommended protective systems shall be documented in sufficient detail to establish compliance with OSHA excavation requirements. The recommendations shall be signed by the registered professional engineer, and the report shall be maintained at the job site. When manufactured support systems are used, the manufacturer’s written specifications, recommendations, and limitations shall be maintained at the job site. A designated competent person shall monitor the construction and maintenance of the recommended protective systems and their use in excavations. (3) (4) (5) (6) j. Subsurface Utilities (1) All excavations shall be performed with extreme caution to prevent injury or damage to underground piping or electrical wiring. If there are known underground obstacles, the competent person shall define the appropriate protective measures. (2) Page 7 of 14 Procedure 440.1-57, Excavation, Trenching, and Digging (3) When excavations occur within 2 feet, vertically or horizontally, of a buried electrical or communication cable, exploratory hand trenching shall be done to authenticate the actual location of the cable. Before and during excavations, these additional requirements shall also be met: (a) A records search and review of as-built or other appropriate documents and drawings shall be conducted to determine the potential presence of underground utilities. The area to be excavated shall be swept with a metal detector and/or a buried cable detection system and visible surface and subsurface markings shall be considered. Exploratory trenching may be used at the perimeter of an area to be excavated by probing and trenching on 4-inch centers. The depth of the trench is determined by the depth needed to accommodate the footings, supports, and piping that will be placed inside the perimeter area. Probing may be performed by jetting or dry probing; however, the depth of probing shall always exceed the depth of excavating by at least 1 foot. The selected depth of probing must be consistent; that is, if one hole is probed at 3 feet, another hole cannot be probed at 4 feet. When using water jetting, the competent person in charge of work shall require all workers to wear safety glasses and face shields. The worker actually performing the probing shall wear both a face shield and goggles. (4) The most recent and official controlled hard copy version of this directive resides with NETL’s Directives Coordinator. An electronic version of the controlled directive has been placed on the NETL Intranet for employee use. Printed hard copies of this electronic version are considered noncontrolled documents. (b) (c) (d) (e) k. Operations (1) Before excavations with a backhoe, updated utility engineering drawings must be used to ensure where lines are buried; if that is not possible, then the use of electronic detection equipment must be used to discover any potential underground lines. There shall be an observer at all times to watch the backhoe bucket. This observer should be stationed adjacent to the excavation and outside the swing radius of the bucket to avoid the operations of the backhoe. The observer is responsible for visually identifying any obstruction while the bucket is excavating and alerting the operator immediately if any obstructions are observed. If the observer leaves the excavation area, excavation efforts shall be stopped immediately until an observer returns. If pipe or other obstacles are encountered, shoring and hand excavation are required until the obstacles are identified and cleared. (2) (3) Page 8 of 14 Procedure 440.1-57, Excavation, Trenching, and Digging (4) Air-operated clay spades may be used during hand excavations, but extreme care should be taken. During hand excavations, if a worker’s head is below the top of the excavation or if the trench is greater than 4 feet deep, shoring or sloping is required. Should any underground obstructions be encountered, the observer or backhoe operator must immediately notify the proper personnel to assist in identification of the obstruction and its possible removal or rerouting. (5) The most recent and official controlled hard copy version of this directive resides with NETL’s Directives Coordinator. An electronic version of the controlled directive has been placed on the NETL Intranet for employee use. Printed hard copies of this electronic version are considered noncontrolled documents. (6) 4. RESPONSIBILITIES a. Work Coordinators (1) (2) Ensure that work permits are obtained when required. Ensure that workers under their supervision are adequately trained, as required by NETL, prior to assigning them work that requires a work permit. Ensure that workers expected to work on a job have read the work permit or had the hazards and requirements verbally explained to them. Ensure that the work permit has been signed by the organization(s) performing the work. Ensure that air monitoring is conducted prior to permit-required confined space entries in accordance with 29 CFR 1910.146 and 29 CFR 1926.651. Ensure that outside contractors are made familiar with this document and they follow applicable requirements. Ensure that a competent person is available during the course of the project (if the work coordinator is not a competent person). (3) (4) (5) (6) (7) b. Competent Persons (1) (2) Conduct daily inspections of excavations and trenching. Conduct inspections after every rainstorm or other hazard-increasing event and increase safeguards against slides and cave-ins as necessary. c. Organizations Performing the Work (1) Comply with all requirements on the work permit. Page 9 of 14 Procedure 440.1-57, Excavation, Trenching, and Digging (2) Understand all of the hazards and protective measures listed on the work permit prior to beginning work. Ensure that their workers are adequately trained, as required by NETL, prior to performing permitted work. Sign the work permit. Notify the work coordinator or ESH&D about any ES&H problems or concerns. Provide and make available a competent person per 29 CFR 1926, Subpart P for any excavation work performed. (3) The most recent and official controlled hard copy version of this directive resides with NETL’s Directives Coordinator. An electronic version of the controlled directive has been placed on the NETL Intranet for employee use. Printed hard copies of this electronic version are considered noncontrolled documents. (4) (5) (6) d. Designated ES&HD Representative (1) Survey the area to ensure all hazards are adequately identified, controlled, and documented on the work permit. Approve the work permit. Ensure all people expected to work on the job have read the work permit or had the hazards and requirements verbally explained to them. Make any additional arrangements that are necessary to ensure the safety of the workers during the permitted work. (2) (3) (4) 5. TRAINING a. Training may be required prior to obtaining a permit. If there is a question about whether or not a worker has had adequate training, the worker or his/her line manager should discuss the worker’s training with the ES&HD. Training is required prior to entering a confined space. (1) Confined space entrants and attendees shall be trained according to the NETL procedure on confined space entry. In lieu of meeting NETL’s confined space training requirements, at the designated ES&HD representative’s discretion, entrants may be trained in the specific hazards of the confined space that is to be entered. (2) b. Confined Space Entry — The entrants, attendants, and rescue personnel shall be trained according to 29 CFR 1910.146 requirements. The designated ES&HD representative shall have had at least equivalent training. Page 10 of 14 Procedure 440.1-57, Excavation, Trenching, and Digging c. Excavations operations must utilize a competent person(s) trained in excavation hazards associated with trenching operations, and have authority to correct/eliminate the hazards they observe. 6. The most recent and official controlled hard copy version of this directive resides with NETL’s Directives Coordinator. An electronic version of the controlled directive has been placed on the NETL Intranet for employee use. Printed hard copies of this electronic version are considered noncontrolled documents. RECORD CONTROL a. Digging permits shall be maintained by the work coordinator during the active operation. A copy of each permit shall be maintained in central ES&H records. The permits shall be retained according to DOE Environmental Records Schedule, Item 3b5. Destroy 3 years after related permit expires. (N1-434-98-28) 7. REQUIREMENTS a. b. c. d. 29 CFR 1910.146, Permit-Required Confined Spaces. 29 CFR 1926, Subpart P, Excavations. 29 CFR 1926.21, Safety Training and Education. 25 PA Code Chapter 102, Erosion Control. 8. REFERENCES a. b. c. d. NETL Procedure 440.1-12, Worker Protection Program Implementation. NETL Procedure 440.1-16, Confined Space Entry. NETL Procedure 440.1-23, Fall Protection Program. NFPA 241, Safeguarding Construction, Alteration, and Demolition Operations. 9. DEFINITIONS a. Bell-Bottom Pier Hole — A type of shaft or footing excavation, the bottom of which is made larger than the cross section above to form a belled shape. Benching (Benching System) — A method of protecting employees from cave-ins by excavating the sides of an excavation to form one or a series of horizontal levels or steps, usually with vertical or near-vertical surfaces between levels. Cave-In — The separation of a mass of soil or rock materials from the side of an excavation, or the loss of soil from under a trench shield for support system and its sudden movement into the excavation, either by falling or sliding, in sufficient quantity so that it could entrap, bury, or otherwise injure and immobilize a person. b. c. Page 11 of 14 Procedure 440.1-57, Excavation, Trenching, and Digging d. Competent Person — The OSHA definition is one who is capable of identifying existing and predictable hazards in the surroundings or working conditions which are unsanitary, hazardous, or dangerous to employees, and who has authorization to take prompt corrective measures to eliminate them. ES&H Record Center — Locations at each site where ES&H records are kept. ES&HD Representative — The authorized ESH&D representative (oftentimes NETL’s soil quality manager) who signs and approves the work permit and who shall be trained in supervisory-level confined space entry procedures. Excavation — Any man-made cut, cavity, trench, or depression in an earth surface formed by earth removal. Hazardous Atmosphere — An atmosphere which by reason of being explosive, flammable, poisonous, corrosive, oxidizing, irritating, oxygen deficient, toxic, or otherwise harmful, may cause death, illness, or injury. Permit-Required Confined Space — A confined space that has one or more of the following characteristics: (1) (2) (3) Contains or has the potential to contain a hazardous atmosphere. Contains a material that has the potential for engulfing an entrant. Has an internal configuration such that an entrant could be trapped or asphyxiated by inwardly converging walls or by a floor that slopes downward and tapers to a smaller cross-section. Contains any other recognized serious safety or health hazard. e. The most recent and official controlled hard copy version of this directive resides with NETL’s Directives Coordinator. An electronic version of the controlled directive has been placed on the NETL Intranet for employee use. Printed hard copies of this electronic version are considered noncontrolled documents. f. g. h. i. (4) j. Shoring (Shoring System) — A structure such as a metal hydraulic, mechanical, or timber shoring system that supports the sides of an excavation and is designed to prevent cave-ins. Sloping (Sloping System) — A method of protecting employees from cave-ins by excavating to form sides that are inclined away from the excavation so as to prevent cave-ins. Shielding (Shielding System) — A method of providing protection utilizing pre-made lightweight aluminum trench shields to prevent cave-ins. Stable Rock — Natural solid mineral material that can be excavated with vertical sides and will remain intact while exposed. k. l. m. Page 12 of 14 Procedure 440.1-57, Excavation, Trenching, and Digging n. Trench (Trench Excavation) — A narrow excavation (in relation to its length) made below the surface of the ground. In general, the depth is greater than the width, but the width of a trench (measured at the bottom) is not greater than 15 feet. Work Coordinator — The person who supervises an excavation, trenching, or digging operation in accordance with this document. o. The most recent and official controlled hard copy version of this directive resides with NETL’s Directives Coordinator. An electronic version of the controlled directive has been placed on the NETL Intranet for employee use. Printed hard copies of this electronic version are considered noncontrolled documents. Page 13 of 14 Procedure 440.1-57, Excavation, Trenching, and Digging 10. REVISION HISTORY DATE 9/19/07 SUMMARY OF CHANGES To establish a permit system to control hazards related to excavation, trenching, and digging at NETL. It is not the intent of this document to detail how excavation should be conducted. The organization performing the excavation must do so according to the regulatory references listed in the procedure. VERSION Original The most recent and official controlled hard copy version of this directive resides with NETL’s Directives Coordinator. An electronic version of the controlled directive has been placed on the NETL Intranet for employee use. Printed hard copies of this electronic version are considered noncontrolled documents. Page 14 of 14 The most recent and official controlled hard copy version of this directive resides with NETL’s Directives Coordinator. An electronic version of the controlled directive has been placed on the NETL Intranet for employee use. Printed hard copies of this electronic version are considered noncontrolled documents. Procedure 440.1-57, Excavation, Trenching, and Digging FLOW CHART OF PERMIT ISSUANCE Page 1 of 1 ATTACHMENT 1