Controlled in-situ burning of spilled oil. Good practice guidelines for incident management and emergency response personnel

Transcription

1 Controed in-situ burning of spied oi Good practice guideines for incident management and emergency response personne

2 The goba oi and gas industry association for environmenta and socia issues Leve 14, City Tower, 40 Basingha Street, London EC2V 5DE, United Kingdom Teephone: +44 (0) Facsimie: +44 (0) E-mai: Website: Internationa Association of Oi & Gas Producers Registered office Leve 14, City Tower, 40 Basingha Street, London EC2V 5DE, United Kingdom Teephone: +44 (0) Facsimie: +44 (0) E-mai: Website: Brusses office Bouevard du Souverain 165, 4th Foor, B-1160 Brusses, Begium Teephone: +32 (0) Facsimie: +32 (0) E-mai: Houston office Westheimer Road, Suite 1100, Houston, Texas 77042, USA Teephone: +1 (713) E-mai: IOGP Report 523 Date of pubication: 2016 IPIECA-IOGP 2016 A rights reserved. No part of this pubication may be reproduced, stored in a retrieva system, or transmitted in any form or by any means, eectronic, mechanica, photocopying, recording or otherwise, without the prior consent of IPIECA. Discaimer Whie every effort has been made to ensure the accuracy of the information contained in this pubication, neither IPIECA, IOGP nor any of their members past, present or future warrants its accuracy or wi, regardess of its or their negigence, assume iabiity for any foreseeabe or unforeseeabe use made of this pubication. Consequenty, such use is at the recipient s own risk on the basis that any use by the recipient constitutes agreement to the terms of this discaimer. The information contained in this pubication does not purport to constitute professiona advice from the various content contributors and neither IPIECA, IOGP nor their members accept any responsibiity whatsoever for the consequences of the use or misuse of such documentation. This document may provide guidance suppementa to the requirements of oca egisation. However, nothing herein is intended to repace, amend, supersede or otherwise depart from such requirements. In the event of any confict or contradiction between the provisions of this document and oca egisation, appicabe aws sha prevai.

3 Controed in-situ burning of spied oi Good practice guideines for incident management and emergency response personne

4 IPIECA IOGP Preface This pubication is part of the IPIECA-IOGP Good Practice Guide Series which summarizes current views on good practice for a range of oi spi preparedness and response topics. The series aims to hep aign industry practices and activities, inform stakehoders, and serve as a communication too to promote awareness and education. The series updates and repaces the we-estabished IPIECA Oi Spi Report Series pubished between 1990 and It covers topics that are broady appicabe both to exporation and production, as we as shipping and transportation activities. The revisions are being undertaken by the IOGP-IPIECA Oi Spi Response Joint Industry Project (JIP). The JIP was estabished in 2011 to impement earning opportunities in respect of oi spi preparedness and response foowing the Apri 2010 we contro incident in the Guf of Mexico. The origina IPIECA Report Series wi be progressivey withdrawn upon pubication of the various tites in this new Good Practice Guide Series during Note on good practice Good practice in the context of the JIP is a statement of internationay-recognized guideines, practices and procedures that wi enabe the oi and gas industry to deiver acceptabe heath, safety and environmenta performance. Good practice for a particuar subject wi change over time in the ight of advances in technoogy, practica experience and scientific understanding, as we as changes in the poitica and socia environment. 2

5 CONTROLLED IN-SITU BURNING OF SPILLED OIL Contents Preface 2 Introduction 4 An overview of ISB 6 The science of burning 6 Ignition and burning requirements 8 ISB decision making 9 Decision making using net environmenta 9 benefit anaysis Reguatory approvas 10 Human heath and environmenta concerns 10 Operationa feasibiity for ISB 12 Oi behaviour and properties 12 Emusified and heavy ois 13 Treating agents 13 Infuence of environmenta conditions 14 ISB appication 16 On-and spis 16 On-water spis 17 Nearshore and shoreines 17 Uncontained sicks on water 18 Operationa hazards and considerations 18 Smoke contro (smoke management) 18 Biota 19 Soi heating 19 Weather conditions 20 Panning a burn 21 Equipment, vesses and vehices for the burn crew 21 Smoke management 21 Evacuation and safety zone 22 Firebreaks 22 Fire contro 23 Ignition pan 24 Impementing a burn 24 Pre-burn safety briefing 24 Ignition 24 Burn monitoring 25 Mop-up or site cean-up 25 Post-burn actions 25 Operationa summary reports 25 Emergency stabiization 26 Post-burn observations and recovery monitoring 26 Rehabiitation 26 Burn residue 27 ISB equipment 29 Ignition devices 29 Heicopter under-sung ignition devices 29 Handhed and mobie patforms for igniters 29 Non-commercia ignition devices 30 Fire-resistant booms 32 Conventiona booms 33 Support vesses for ISB on water 33 Support aircraft for ISB 33 Operationa monitoring for safety 34 and burn contro Exposure of responders to heat 34 The behaviour and distribution of ISB emissions 34 Particuate matter 35 Safe distances 36 Monitoring and samping for emissions 36 Operationa monitoring 38 Bibiography 39 Appendix 1: Estimation of the amount of 42 oi burned and the burn efficiency Appendix 2: Boom depoyment and 44 towing configurations Depoyment of booms for ISB 44 Fire boom towing configurations 45 Acknowedgements 47 3

6 IPIECA IOGP Introduction In-situ burning (ISB) is the controed combustion or burning of spied oi s hydrocarbon vapours in pace. ISB can rapidy remove oi from a and, snow, ice or water surface, and combusts it to mosty CO 2 and water. ISB can rapidy reduce the voume of spied oi, and thus greaty reduces the need to coect, store, transport and dispose of recovered oi. ISB can aso shorten the overa response time, thus aiding environmenta recovery. This guide contains information about the insitu burning of oi spis and the scientific aspects of the burning process and its effects. It aso presents practica information on the procedures and equipment required for ISB operations. ISB is a non-mechanica response option as, for exampe, is the appication of oi spi dispersants. However, rather than using chemicas to remove spied oi, the oi is removed by combustion of its hydrocarbon vapours. The best spi cean-up strategy wi ikey invove a combination of a avaiabe response options. When combining different cean-up techniques, the objective shoud be to find the optima mix of equipment, personne and techniques that affords environmenta protection and mitigates potentia impacts. ISB can be used to remove oi spied on hard surfaces, sois, ice and snow on and, snow and ice on water, on sea ice and on water. During an on-water spi, ISB can be used in open waters (whether inand or offshore). Burning can be repeated in cases where sufficient oi remains. ISB can be used in conjunction with other techniques to cean up different areas of a sick. Ignition of voatie ois is achieved easiy, whie heavier ois often require the use of an acceerant or promoter, such as diese fue, to ignite the hydrocarbon vapours. If not enough vapours are produced, the fire wi either not start or wi be quicky extinguished. The amount of vapours produced is dependent on the amount of heat radiated back to the oi, which encourages further vaporization. If the oi sick is too thin, some of this heat is conducted through the sick and ost to the water ayer beow. Insufficient heating of a sick reduces vaporization rates and owers vapour concentrations, unti eventuay, concentrations are too ow to sustain combustion. Oi that is heaviy emusified with water can be ignited if sufficient heat is suppied to remove water and reease hydrocarbon vapours. Containment of the oi on water may be necessary when carrying out ISB as the oi sick needs to be thick enough to ignite and sustain a burn. Once burning, the heat radiated back to the sick is usuay sufficient to aow combustion down to an oi thickness of around mm. The oi burn rate is argey a function of oi type and its degree of weathering. ISB has been shown to be successfu in many varying habitats. ISB on and has incuded burning oied marshes, vegetation and tundra. ISB on ice has aso been successfuy practiced on both soid ice and among broken ice. ISB on water has been demonstrated in open water, nearshore environments, protected bays and rivers. Whie the fundamentas for ISB remain the same, the tactics wi vary given the habitat specifics and spi circumstances. For exampe: ISB on and can invove the use of budozers and front-end oaders to contain and thicken spied oi, or trenchers to cut ditches into which oi can be pooed to support ignitabiity; ISB on snow and ice may not require any further containment as the snow/ice can serve as a natura boundary; sea ice eads can hep to create thicker pockets of oi and can aso contain the oi once ignited; and ISB on water typicay invoves vesses towing fire booms at conventiona speeds to both encounter and contain the oi. 4

7 CONTROLLED IN-SITU BURNING OF SPILLED OIL Burning oi on and or wetands is a technique that can reduce the environmenta impact of oi spis. Burning vegetation is a frequent method of protecting and maintaining certain ecosystems. The important factors reating to burning are the water eve of wetands and the moisture content of sois. Burning under the correct circumstances wi not affect roots and thus restoration is rapid. Experience has shown that burns can be conducted safey for responders, the pubic and the environment. Set-back distances prevent exposure to high eves of heat from a burn. Firebreaks are created to avoid spreading fire to other ocations. The main advantages and disadvantages of ISB are summarized in Tabe 1. The most significant advantage is the capacity to rapidy remove arge amounts of oi. The most discernibe disadvantage is the production of dark smoke pumes, which resuts in pubic concern about aesthetics and emissions hazards. Tabe 1 Advantages and disadvantages of ISB Advantages Rapid remova of oi Minima equipment requirement High efficiency rates Reduced voume of oiy waste for disposa Can be used on amost any habitat and on most ois Disadvantages Back smoke pume (aesthetics and emissions concerns) Risk of fire spreading or oss of fire contro Residue may need to be recovered ISB can rapidy eiminate arge amounts of spied oi; this can prevent the oi from spreading to other areas and reduces the risk of a spi contacting new habitats, such as a shoreine in offshore spis. In addition, ISB can be appied in remote areas where other techniques cannot be used due to a ack of access or infrastructure, e.g. on ice. Burns produce particuate matter (soot). Particuate matter at ground eve is a heath concern, particuary when in cose proximity to the fire and under the pume. The concentrations of these emissions during an ISB have been widey studied and generay found to be beow the eves that are of concern to human heath. 5

8 IPIECA IOGP An overview of ISB The science of burning The fundamentas of ISB are simiar to that of any fire, namey that fue, oxygen, and heat are required for oi to ignite. In the event of an oi spi, the oi vapours provide the fue to support combustion. Fresh oi wi typicay ignite once an ignition source is appied. As oi vapour burns, the heat causes more vapours to be reeased, known as vaporization. The vaporization process of oi must be sufficient to yied steady-state burning, in which vaporization and burn rates are reativey the same. The burn rate is imited by the amount of oxygen avaiabe and the heat radiated back to the oi. The burn rate wi aso rey on the type of oi and its degree of weathering, e.g. evaporation. If there are not enough vapours, the oi wi not ignite or wi quicky extinguish once ignited. The amount of vapours produced is dependent on the amount of heat radiated back to the oi, which is estimated to be about 2 3% of the heat produced. Fresh crude oi needs to be at east 1 mm thick to yied enough vapours to aow ignition on water, whie oi that has undergone extensive weathering may need to be between 2 5 mm thick. Heavy fue ois wi need to be contained to maintain a sick thickness of around 10 mm before they can be ignited. Once ignited, the heat radiated back to a sick wi usuay be sufficient to aow the burn to continue unti the oi sick is around 2 3 mm thick. As a sick thins, its insuating capacity weakens and more heat is ost to the media beneath the sick (e.g. soi or water), eventuay resuting in insufficient heat to continue to vaporize the oi and sustain combustion. Research has shown that virtuay a ois wi burn if the sick is thick enough. Oi spi containment booms and other containment methods are often used to increase a sick s thickness or to maintain it at the thickness required for burning. The basic concepts of in-situ burning are iustrated in the photographs beow and summarized in Tabe 2 on page 7. (a) Oi coected and hed by a fire-resistant boom or within a segregated area. (a) (b) (b) Ignition fame appied to oi creates vapour which ignites. (c) Fame spreads over sick and burns oi down to around 1 mm thickness. (c) (d) (d) When vapour is insufficient to maintain combustion, the fire ends. Eastec Inc. 6

9 CONTROLLED IN-SITU BURNING OF SPILLED OIL Tabe 2 Basic questions and answers about in-situ burning Questions Answers What burns? How do burns proceed? How much heat radiates downward? What is the minimum sick thickness that can burn? What is a typica burn pattern? What is the expected oi remova efficiency? What is a typica oi remova rate? What is a typica oi voume remova rate? How fast can a fame spread? How high are fames? What is the potentia for soot formation? Hydrocarbon vapours from the spied oi. Heat vaporizes spied oi for ignition, and if vapour concentrations are high enough a burn can be sustained. Ony about 2% of heat produced is radiated downward and dissipates rapidy in surface waters or saturated sois. This depends on the oi, but it is best to have >2 4 mm for sustained burning. Once ignited, burns wi proceed downwind aong a sick and reduce the sick thickness to ~1 mm before fire extinction. This depends on the initia thickness of the sick; it can be as high as 90+%. 1 to 4 mm of oi sick thickness can be removed per minute for an oi poo (thick sick) burn. 2,000 to 5,000 itres for each m 2 of a sick per day can be removed. For contained sicks on water, typica burn rates can remove ~150 m 2 of spied oi in an hour. Fames can move quicky for voatie ois ( m/s); they can spread twice that speed downwind, and approach speeds of ~100 km/hour. The rue of thumb is ~1.5 x fire diameter. This is greatest when the vaporization rate exceeds the burn rate (i.e. incompete combustion due to O 2 imitation). Weathered or emusified oi can be difficut to ignite because much more energy is needed to remove water before it is abe to heat the oi; the addition of an acceerant (e.g. diese fue) or promoter may therefore be necessary to achieve ignition. Boom tows containing both unemusified oi and emusified oi on a water surface can be burned by first igniting the unemusified portion. The heat from burning the unemusified oi causes the water content to be reeased from the emusified oi, and eventuay the oi vapours become sufficient to support ignition. Once ignited, most water-inoi emusions wi continue to burn. The photograph on the right shows the progression of a burn as it spreads from the unemusified oi to the emusified oi (red coour); this eventuay ed to both ois burning simutaneousy. Eastec Inc. A burn of unemusified and emusified oi 7

10 IPIECA IOGP Eastec Inc. Incompete combustion resuts in materia being eft behind after a fire is extinguished. This is known as burn residue. Residue can range from britte or stiff toffy-ike materia to a iquid simiar to the origina oi. Highy efficient burns of heavy crude oi can resut in the formation of dense residue that sinks into the water coumn. The sma amounts of residue present after such an on-water burn (see photograph) typicay represent <0.1% of the oi burned. An exampe of residue from a highy effective muti-hour burn at sea. Ignition and burning requirements In genera, most ois on water wi burn if sicks are more than 2 4 mm thick. On and or wetands, the situation is simiar, athough oi with a thickness of 1 mm or ess can be burned in a sustained manner on grassand because of heat from the burning of vegetative fues. Heavy ois wi require a sma amount of primer (promoter or acceerant), such as diese fue, to start ignition. A promoter or acceerant woud be appied to just a few spots on a sick which are judged to be near or on the thickest portion. Easy ignition of the promoter or acceerant can heat the underying oi and increase its vaporization rate and its potentia for ignition. Once burning, heavy ois wi burn we, and even emusified oi can break down and burn. Tabe 3 shows the ignition characteristics of various ois. These characteristics are independent of whether the oi is on and or on water. Tabe 3 Burning properties of various ois Oi Overa burnabiity a Ease of ignition Fame spreading speed Burning rate b (mm/min) Sootiness of fame c Efficiency d (%) Gasoine very high very easy very rapid 4 medium Diese fue high easy moderate 3.5 very high Light crude high easy moderate to rapid 3.5 high Medium crude moderate easy moderate 3.5 medium Heavy crude moderate medium moderate 3 medium Weathered moderate add promoter sow 2.5 to 3 ow Crude oi with ice moderate difficut, add promoter sow 2 medium Light fue oi moderate difficut, add promoter sow 2.5 ow Heavy fue oi moderate add promoter sow 2 to 3 ow Diuted bitumen (dibit) moderate easy, if fresh moderate 2 to 3 medium Weathered dibit moderate add promoter sow 2 to 3 medium Emusified oi ow add promoter sow 2 to 3 ow Bitumen ow add promoter sow 2 to 3 ow Used oi very ow add promoter sow 1 to 2 medium (a) Overa burnabiity is a genera refection of the ease of ignition, burn sustainabiity and its efficiency of oi remova. (b) Typica rates ony. To convert rate to itres/m 2 /hour mutipy by 60. (c) A descriptive abe to refect the degree of combustion and quantity of soot in a burn pume (therefore, the darkness or sootiness of a smoke pume). (d) Efficiency of a burn is estimated here from historic information based argey on reported residue amounts. 8

11 CONTROLLED IN-SITU BURNING OF SPILLED OIL ISB decision making When an oi spi occurs, information must be obtained on the various factors that woud infuence the decision as to whether or not an ISB operation shoud be considered. Such factors incude reguatory requirements, safety, oi properties, environmenta and weather conditions, resources and geographica ocation. The main considerations are isted in Tabe 4. Tabe 4 Factors in the seection of burning as a spi response option Appropriateness Is the ocation suitabe for burning? Distance from popuated areas Burn distance from other combustibes Distance of smoke pume trajectory from residences Is burning feasibe, and can burning be carried out safey? Legisation and reguations Can necessary permissions be obtained? Can stipuated conditions be met? Feasibiity Is the oi burnabe? Oi can be ignited (<25 30% evaporated) Oi is thicker than 2 3 mm Emusification: <20 25% water Weather forecast? Winds <18 knots for ignition/ <20 knots for a sustained burn If booms are necessary, is wave height <1 m? Equipment avaiabiity? What are the resuts from a net environmenta benefit anaysis (NEBA) i.e. is burning the best option in this case? An ISB feasibiity anaysis wi often incude an evauation of the geographic ocation and any preexisting prohibitions. For exampe, ISB approvas may be constrained when requested in cose proximity to: human habitation; and industria faciities with fire safety hazards, e.g. petroeum oading, production or exporation faciities, areas designated for miitary target practice or areas of former munitions dumping. Sensitive areas, such as shoreines, nature preserves, bird coonies, or nationa or state/provincia parks coud be of reguatory concern, yet these areas are often good candidates for ISB when minima intrusion and rapid oi remova is desired. Decision making using net environmenta benefit anaysis The net environmenta benefit anaysis (NEBA) process can hep to identify appropriate response strategies that resut in the owest overa environmenta and socio-economic impact. The NEBA process is used for pre-spi contingency panning and for decision making during a response. NEBA considers and compares the advantages and disadvantages of different spi response techniques with those of taking no response action, taking account of the operating conditions and anticipated effectiveness of each technique and actua spi circumstances, incuding ocation. No singe response technique is competey effective or risk-free. Any response operation wi ikey invove a combination of response techniques, because: 9

12 IPIECA IOGP each technique has different strengths and weaknesses reative to the circumstances of the spi; spi circumstances change over time; and arger spis with greater spatia extent of sicks may benefit from various techniques used in different ocations simutaneousy. NEBA shoud be conducted with appropriate reguatory agencies and other stakehoders as part of spi contingency panning (see IPIECA-IOGP 2015). Reguatory approvas Most countries have not yet estabished approva processes for conducting ISB. In the USA, which has the most deveoped reguatory guidance and approva process for ISB: ISB is now incuded in many muti-state, regiona contingency pans, and the process for obtaining approva to conduct ISB operations has been reativey we-defined on a regiona basis under the US Nationa Contingency Pan; response decision making for ISB refects the scae of a spi or intended burn: arger spis invove more agencies, and approva requests receive greater scrutiny; sma spis and burns may be handed by oca emergency responders and firefighters; and pre-approva zones for streamined decision making have been identified for coasta areas on a regiona basis. As more countries seek to use ISB in oi spi response operations, it is anticipated that an approva process wi be deveoped, simiar to the dispersant use approva process, which woud entai government and stakehoder engagement. Many state/provincia governments aready have provisions for using prescribed burning to manage and, and the in-situ burning of spied oi may fit into these provisions. In genera, reguatory agencies are most concerned with operationa safety (i.e. fire contro and responder safety) and pubic safety (i.e. fire contro and the potentia for effects from smoke pumes on air quaity and heath) during response operations. See Operationa monitoring for safety and burn contro (page 34) for information on safety. Some jurisdictions have waived air quaity imits for specia cases, such as during an emergency. Human heath and environmenta concerns The primary heath concerns reate to emissions produced by ISB. Data indicate that the combustion of oi yieds mosty CO 2 and water to the atmosphere (up to 85% of emissions), inert carbon partices, i.e. soot, which coours the smoke pumes (around 10%), and sma amounts of various other gases and PAHs (poycycic aromatic compounds organic compounds containing carbon and hydrogen). Of the soot partices, attention is focused mosty on a cass of sma particuate matter, PM 2.5 the 2.5 μm-sized partices (Figure 1). Figure 1 Reative partice sizes (based on data courtesy of the Nationa Widfire Coordination Group) 10

13 CONTROLLED IN-SITU BURNING OF SPILLED OIL Inhaation of PM 2.5 coud be a heath concern to vunerabe groups, such as the edery, the very young, and those with compromised ung function. Pubic heath concerns with PM 2.5 are inked to onger-term exposure rather than to short-duration events (e.g a burn); however, exposure to sufficient quantities can ead to irritation of the eyes, nose, throat and respiratory tract, and can aggravate existing conditions such as asthma. These effects are usuay temporary and shoud resove after exposure stops. It shoud be noted that: hydrocarbons wi evaporate from oi sicks, whether burned or not; monitoring data consistenty show that concentrations of emission constituents decine quicky as the distance from a burn increases; and data from monitoring of the Kuwait War oi fires and Deepwater Horizon incident do not indicate that the concentrations of emission constituents reeased from burning are of concern with regard to human heath. The gases and emissions to the atmosphere that may arise from ISB are described in Box 1. There has been interest in whether ISB generates dioxins or dibenzofurans. Anaysis of particuates precipitated downwind and residue from severa fires has found dioxins and dibenzofurans to be at background eves, indicating no production during ISB. Box 1 Gases and other emissions to the atmosphere resuting from ISB Carbon dioxide (CO 2 ): carbon dioxide is the end resut of combustion and is produced during in-situ burning. Norma atmospheric eves are about 300 ppm (parts per miion), and eves cose to a burn can be around 500 ppm, which presents no danger to humans. Concentrations at ground eve are typicay much higher than in the pume. In addition to the reease of CO 2 and water (which constitutes ~85% of smoke pume contents), and particuate matter (PM, soot in the pume), a sma number of other ow-concentration emissions are produced by ISB. Poyaromatic hydrocarbons (PAHs): the concentration of PAHs, both in a pume and as particuate precipitation at ground eve, is often an order of magnitude ess than the origina concentration of PAHs in the spied oi. This incudes the concentration of muti-ringed (5 or 6 rings) PAHs, which are destroyed by the fire. Voatie organic compounds (VOCs): when oi is burned, these compounds evaporate and are burned or reeased. The concentration of voatie compounds at severa test burns was reativey ow compared to an evaporating, unburned sick. Carbonys: oi burns produce ow amounts of partiay-oxidized materia, sometimes referred to as carbonys or by their main constituents, adehydes (formadehyde, acetadehyde, etc.) or ketones (acetone, etc.). Carbonys from crude oi fires are produced at very ow concentrations and are beow heath concern eves even cose to the fire. Carbon monoxide: carbon monoxide eves are usuay at or beow the owest detection eves of most instruments and thus do not pose any hazard to humans. The gas has ony been measured when a burn appears to be inefficient, such as when water is sprayed into the fire. Suphur dioxide (SO 2 ): this is usuay not detected at significant eves, and sometimes not even at measurabe eves in an in-situ oi burn. SO 2 reacts with water to produce suphuric acid, which can be detected at eves ower than the suphur content of the spied oi. Other gases: attempts were made to measure oxides of nitrogen and other fixed gases. None were detected in severa experiments. 11

14 IPIECA IOGP Other topics of concern reated to ISB incude potentia water quaity and environmenta effects (see Tabe 5). Information from past burns and tests indicate that ISB has itte effect on water quaity. Studies have shown that no measurabe quantity of oi is reeased to the water coumn during burning. For oi spis on water that are not burned, there is greater potentia for impacts on water quaity. For spis on and or shoreines, the remova of surface oi by burning is a positive outcome, and the effects of heat and fire contro can be addressed in panning and execution. The distance of ISB operations from vunerabe groups is a key operationa contro point to imit any potentia for exposure. Tabe 5 Topics of concern reated to the use of ISB Pubic Heath Air quaity Water quaity Effects on and Concern Effects on birds/animas Heating of surface water ayers and surface sois Mitigation A burn shoud be greater than 1 km from any residence of the genera pubic that is downwind of a burn pume so that exposure to PM does not exceed threshods. A burn shoud be greater than 4 km from mutipe residences of the genera pubic that are downwind of a burn pume, to account for additiona time for shetering in pace or temporary evacuation. Predict emissions and safe distances. Studies show that effects are negigibe. Habitat and season dependent, but can be accommodated by burn design and timing. Habitat and season dependent, but can be accommodated by burn design, timing and hazing. Water is a strong heat sink. Studies show that burns have negigibe effects on surface waters or soi temperatures. Operationa feasibiity for ISB There are severa key points to be considered when determining the operationa feasibiity for ISB. Responder safety shoud aways be the first priority when evauating ISB feasibiity. Trained responders wi be required, with preference being given to those who are experienced in the use of ISB. Appropriate equipment necessary for ignition and containment wi be required. Responders and equipment wi need to be ready and avaiabe within the ISB window of opportunity. An organizationa structure shoud be in pace to ensure good communication and reporting. Roes incude burn boss, ignition crew, fire contro team, etc. The spi circumstances (e.g. oi type, behaviour and properties, ocation, weather conditions, etc.) wi infuence the ikeihood of a successfu burn, burn strategy and tactics, and possiby infuence reguatory approvas for carrying out ISB. Oi behaviour and properties As soon as oi has been spit, it begins to undergo a series of changes in state, infuenced by the conditions in which it was spit; this is known as weathering. Weathering is the ateration of the physica and chemica properties of oi through natura processes, incuding spreading, evaporation, dissoution, photo-oxidation, emusification, sedimentation and biodegradation. 12

15 CONTROLLED IN-SITU BURNING OF SPILLED OIL Further information on oi behaviour and properties can be found in ITOPF s Technica Information Paper, Fate of Marine Oi Spis (see the Bibiography on page 39). To determine whether ISB wi be feasibe on a particuar oi sick, it is important to understand how these processes change the properties of the particuar spied oi and utimatey affect the oi s abiity to ignite and sustain the burn. Understanding a particuar oi s properties prior to an event, e.g. the tendency for the oi to emusify, or the percentage rate of evaporation at various temperatures, wi expedite the decision making process during an incident. A key oi property for burning is its voatiity. As a rue, the greater the percentage of voatie compounds in an oi, the more easiy it wi ignite and continue to burn. The rate of evaporation depends on ambient temperatures and wind speed. In genera, oi components with a boiing point <200 C wi evaporate within 24 hours. It can therefore be difficut to ignite weathered ois (since most of the more voatie compounds wi have vaporized) and heavy crude ois which contain minor amounts of voatie compounds. Higher ignition temperatures, the addition of fire promoters or acceerants and/or onger ignition exposure times may be required. Emusified and heavy ois In genera, unstabe oi emusions can be ignited and wi sustain burning as the emusion wi be quicky broken down during the burning process. By contrast, stabe oi emusions are difficut to ignite because of the arge amount of energy required to heat the water (so that it vaporizes) and then heat the spied oi. Additiona energy is therefore required to vaporize oi in the emusion before burning can be sustained. Test burns have shown that, once emusified oi is ignited and has burned for ong enough, the heat from the burn wi break down the emusion and aow the sick to continue to burn. Emusified oi can be burned aongside unemusified oi, as the heat from burning the unemusified oi wi break down the emusion (see photograph on page 7). Heavy ois do not contain many ighter-weight, voatie hydrocarbons. However, it is now accepted that heavy ois once considered to burn poory, if at a wi burn we under most circumstances. Burning tests of bitumen (very heavy oi) aong with water have been conducted and show a usefu burn rate potentia. Heavy ois, such as Bunker C, burn quite we. Heavy oi burns produce ow emissions compared to crude oi burns and, in particuar, fewer voatie compounds and PAHs are reeased into the air. The residues from heavy oi burns are highy viscous, and when cooed may be soid and even gassy in some cases. Treating agents The use of chemica additives (treating agents) to promote ignition, enhance burning or aid smoke management has been investigated over the years. These agents incude emusion breakers, herding agents, ferrocene, combustion acceerants or promoters, and sorbents (see descriptions beow). Note that the use of a but sorbents for oi spi response is ikey to require advance approva by the designated government agency/agencies. Few are approved for use at the present time. 13

16 IPIECA IOGP Emusion breakers and inhibitors are used to either break down water-in-oi emusions as they weather, or to prevent emusions from forming. They have not been used extensivey in fied trias and are rarey used for on-water or shoreine spis. They woud not be needed for spis on and. Herding agents have been deveoped and tested to increase the thickness of oi sicks on water so that the sicks are thick enough for burning. Outdoor tests in pack-ice conditions and in open waters has shown herders to be effective at thickening sicks. Herders work most effectivey in cam conditions; winds greater than 1.5 m/s or the presence of waves coud overcome their sick-thickening effect. Ferrocene has been used in widand firefighting to reduce and eiminate soot production from burns. Tests have shown that, when mixed with spied oi, ferrocene is highy effective at dose percentages from 1 2%. It is denser than oi and water, so for on-water spis it is usuay premixed and appied just before burning; timing such an appication can therefore be difficut. Ferrocene can aso be encapsuated so that it foats, and in this way can be added to an on-water burn after ignition, athough this is not currenty an estabished practice. Acceerants or promoters (primers) are agents which, when appied to seected spots on an oi sick, are intended to provide sufficient hydrocarbon vapours for ignition. Once ignited, the heat from the primer burn is intended to increase the vaporization of spied oi and support continued burning. Sorbents, such as peat moss, have proven usefu by acting as wicking agents for oi sorbed into debris and sois, and can increase oi removas by encountering and acquiring more oi to burn. Infuence of environmenta conditions Spi circumstances and forecast weather conditions can infuence the decision as to whether or not ISB operations shoud be conducted. The foowing are exampes of specific weather phenomena and their potentia impacts on ISB operations: Wind speed, gusts and shifts in wind direction, pus for on-water spis, wave height and geometry and water current can a jeopardize the safety and effectiveness of a burn operation. Strong winds can make it difficut to ignite the oi, or make a burn difficut or dangerous to contro. In genera, oi can be ignited and burned at wind speeds ess than 10 m/s (<18 knots); however, ower winds speeds are preferred (<5 m/s and <10 knots) for fire contro. Tank tests have shown that at wind speeds greater than 15 m/s (>30 knots) fames do not propagate upwind. This effect can either add to fire contro or constrain oi remova depending on the ocation of the burn in a sick. At higher wind speeds, the concentration of vapours becomes difficut to maintain, and burns can be extinguished. Tank tests have shown that air temperatures from -11 to 23 C and water temperatures from -1 to 17 C did not affect the abiity to burn. Rain can ower the efficiency of a burn due to the cooing effect of water dropets pus the potentia for disruption of a sick which reduces vaporization. For on-water spis, higher sea states can make it difficut to contain the oi to create the thicker sicks necessary for maintaining adequate vapour concentrations. Waves greater than 1 metre in height can weaken the wave conformance of containment booms and ead to faiure. Ice has a minima effect on the abiity of a sick to burn on and. On water, ice can dampen waves and hep to contain a sick, thereby enhancing the abiity to burn. 14

17 CONTROLLED IN-SITU BURNING OF SPILLED OIL Water, ice and snow on and can act as insuators, protecting sois and pants from any downward radiated heat. Burning can be conducted safey at night if the sick properties and weather conditions are weknown. There are exampes of burns carried out safey at night on nearshore and marsh spis. In these cases, the concentrations and ocation of oi were known, and precautions were taken to ensure that the fire did not spread to surrounding areas. Burning at night is a reativey safe choice for cases of thicker, uncontained spis at sea, especiay if the spi is offshore, its extent is weknown and vesse traffic is directed away. However, towing booms at night woud be unsafe under most conditions. Successfu burning in wetands is we documented and important information is avaiabe on the protection of marsh pants and the best times of year to carry out a burn. For exampe: Fooding is a usefu technique for fushing oi out of a wetand to burn, whie protecting the roots of pants from heat and increasing fire contro. Fooding can sometimes be accompished by pacing a berm across drainage ditches or pumping water onto higher-eevation areas. Care shoud be taken to ensure that food water is of simiar sainity to that normay present in the wetand, and that natura drainage conditions are returned after burning. Burning is best conducted when a wetand is wet and sois are saturated, e.g. in spring. It has been observed that water-saturated sois provide sufficient insuation from the heat of a burn, so that temperatures remain beow those known to affect soi biota and pant roots. A NEBA anaysis wi hep the decision making process in dry seasons or times of the year. Ice and snow during cod periods in temperate cimes, apine areas, or in the Arctic or Antarctic can serve as a natura barrier to the spreading of spied oi. Ice and snow aso function as barriers to oi penetration into sois and to soi heating from burns. Many burns have been conducted with oied snow, on ice, or among ice foes (see photographs on the right). Much of the eary ISB research was carried out in Canada to deveop a countermeasure for spied oi in sea ice. Burns can be conducted when the oi is: contained in cose pack-ice conditions (pack ice of 7/10 coverage or greater); contained in drift-ice conditions and is of a sufficient thickness to sustain a burn (drift ice of 2/10 to 6/10 coverage); contained in a fire-resistant boom (generay in open water up to 1/10 ice coverage); trapped aong an ice foe or herded by wind, and has sufficient thickness to support a burn; contained in met poos on top of ice sheets; and contained in open fractures or eads in ice. Environment Canada Left: burning an oi spi that is entirey contained by ice rubbe. Beow: burning oi in an ice ead after a spi experiment. Environment Canada 15

18 IPIECA IOGP ISB appication An important advantage of ISB is that it is a usefu response option whether on and, on water, or on snow or ice. This section describes how ISB is appied in each operating environment. On-and spis Burning oi on and is an estabished and more frequenty used technique than ISB on water. Unique considerations for ISB on and incude the foowing: The effect of oi and heat on soi and vegetation is a prime consideration. Certain types of vegetation are very sensitive to fire, whie others are not or may be fire-dependent. The burn history of a ocation (i.e. the use of ISB or prescribed burning in the past) shoud be reviewed and considered. The history of fire behaviour and habitat recovery is usefu to hep estimate future fire effects and recovery. Prescribed burns are conducted frequenty in many countries to achieve or maintain a widand habitat (e.g. grassands, rangeands, forests) and address concerns with invasive species. Extensive iterature and expertise are avaiabe on prescribed burning, which can be used to support ISB on and. The impact and after-effects from exposure of the subsurface sois (incuding pant roots, tubers, and microorganisms) to heat: this is highy infuenced by soi moisture, depth of oi sorption, and fire intensity. If fire damages sois and roots, etc., revegetation wi be commensuratey sower. Standing water and saturated sois shoud provide adequate insuation from heat. The amount of oi that has penetrated into sois, and the depth of penetration, before and after the proposed fire: if there is itte penetration before the fire, burning wi be abe to remove more oi. Spis to peat bog habitats have been a concern due to observations of fires in dry peat habitats that were difficut to extinguish. However, water-saturated peat cannot burn, so spis in areas of saturated peat coud be candidates for ISB. In terms of burn operations, many of the same considerations appy to and as might appy to burning on water. There are, however, severa important differences: The ease of ignition and oi thickness may not be a significant concern if combustibe materia (vegetative fue), such as dried grass, is avaiabe. Burning where there is dried vegetative materia or wood is simpy a matter of igniting that materia. Fire contro procedures on and differ from those on water. First, a firebreak is needed around the perimeter of the proposed burn area. Sometimes natura barriers, such as rivers, roads, etc. can serve as firebreaks. Once the firebreak is estabished, ignition is typicay begun in the downwind position to give greater contro as the fire must fight its way against the wind. Once ignited, the fire shoud be monitored, especiay near firebreaks. Sufficient resources shoud be avaiabe to extinguish the burn and prevent uncontroed fire propagation. Such resources usuay incude a fire truck with trained firefighters. After the main burn is extinguished, the ocation shoud be monitored for severa hours unti hotspots have cooed and there is no danger of reignition (fare-ups). After the burn is competey extinguished, post-burn monitoring shoud incude a wak-through of the area with coection of sampes for post anaysis, as we direct observation of the surface ayers. Detais to be recorded incude whether: (1) oi has been burned competey; (2) burn residue is present that coud interfere with pant regrowth; (3) oi has penetrated into the soi; and/or (4) there is unburned oi remaining which needs treatment (and if so, coud this oi be burned?). 16

19 CONTROLLED IN-SITU BURNING OF SPILLED OIL The creation of a firebreak can pose a probem in wetands as the periphery often contains sensitive vegetation. Two methods for creating firebreaks in wetands incude using airboats to ower vegetation height and/or wetting a periphery around the oied vegetation. On-water spis The basic process is as foows: (a) coect oi behind a fire-resistant containment boom; (b) sowy pu a fire-resistant boom against the water current to push oi into the boom apex and increase the thickness of the oi; and (c) ignite the oi. In most cases, a fire-resistant boom is depoyed downwind of the spi and a tow is put in pace. When enough oi is coected in the boom, it is ignited as shown in the photograph on the right. If burning extinguishes because there is not enough oi in a boom, the burn can be resumed by heading vesses and towing booms downwind and then turning around into the wind, before re-igniting. Fire contro on water can be achieved in an emergency by reeasing one end of a boom or by increasing the tow speed to force boom faiure. Either action resuts in rapid thinning of the oi sick, a decrease in vaporization and a decine in burning. US Coast Guard Vesse coordination between towing, ignition and support during an on-water burn operation. The boom normay remains depoyed unti the fire is extinguished. The burning and progress of the tow shoud be checked frequenty by personne either onboard aircraft or on a arger vesse. Another potentia situation for on-water burns is where oi has been spied onto or among sea ice and become encapsuated. If accessibe, voatie oi on a surface can be ignited directy with or without the use of an acceerant. Burns have been conducted in various types of sea ice conditions which provide a form of containment (frazi, brash, drift and pack ice) (Buist, et a., 2013). If spied oi becomes encapsuated, oi wi not be accessibe unti warmer weather when met channes form in the ice and oi can migrate to the ice surface. Nearshore and shoreines Barriers such as shoreines, breakwaters, sandbars or sea ice can hep to contain the oi so that it can be burned without the use of fire booms. In these habitats, shoreines can incude ciffs, rocks, grave, piers, breakwaters or sandy sopes. If a spied oi sick is thick enough to reease sufficient vapours for ignition, and other reevant circumstances support burning, a burn wi be feasibe. There shoud be a safe distance between the spied oi and any combustibe materias, such as wooden structures and areas of habitation. Nearshore burning has been successfuy conducted in the Arctic, particuary in cases where the oi is contained by a shoreine. If there is an onshore wind, oi wi be concentrated against the shoreine, increasing its thickness and sustaining a onger burn. 17

20 IPIECA IOGP There can be cases where oi becomes stranded on shores that can be dangerous for responders to access to carry out mechanica response operations. Burning coud therefore be the ony viabe ceanup soution, with its smaer ogistica needs and potentia for remote ignition. Firebreaks in these ocations can be comprised of the surf zone and unvegetated shore areas which have been ceared of unoied debris. The window of opportunity for ISB is between the outgoing and incoming tides. Uncontained sicks on water Two opportunities may exist to burn uncontained sicks on water: (1) in zones of convergences; or (2) when spi conditions generate many thick on-water sicks. Zones of convergence are surface phenomena, driven by winds, which naturay coect the spied oi into thicker concentrations, that can be suitabe for burning. Controed burning of uncontained sicks is rare, but sometimes possibe if a sick is thick enough. If an oi sick is aready fairy thick, it may be advisabe to burn as much as possibe as a first response, and then bring in fire booms to thicken the remaining parts of the sick for a second burn. Four uncontained burns at sea US Coast Guard. When burning an uncontained sick, personne must ensure that there is no direct connection between the oi to be burned and its source, so that the fire is prevented from spreading uncontroaby. In the Macondo incident, some spied oi was ignited without containment (see photograph on the eft). These uncontained burns increased the number of burn operations conducted and the voume of oi removed by ISB. Operationa hazards and considerations The burning of oi on and may invove hazards that are not encountered during burning at sea. For exampe, the sea acts as a barrier between offshore burns and the shoreine, heping to prevent the uncontroed spreading of fire; for on-and burns, however, there is no gap between the burn area and other possibe combustibe and/objects nearby. Specia precautions must therefore be taken when initiating a burn on and. Hazards in, or cose to, the burn area that shoud be considered incude: other unintended combustibes; physica hazards, such as debris, barbed wire, etc.; areas with poor footing, hoes or steep sopes; and areas where vehices may become stranded. Smoke contro (smoke management) The possibe heath effects from exposure to a smoke pume shoud be assessed to determine the preferred burn strategies. The size and trajectory of smoke pumes can be infuenced by decreasing the size of individua fires, and burning in different wind directions and at different times of day. Generay, a safe distance for the genera pubic is a minimum of 1 km downwind from a burn (see Tabe 5 on page 12) and is based on conservative estimates of diution for PM 2.5 concentrations to beow the 24-hour exposure threshod of ess than 35 μg/m 3. The same threshod appies to responders working at a burn site, athough when using appropriate PPE any exposure shoud be minima or negigibe. 18

21 CONTROLLED IN-SITU BURNING OF SPILLED OIL Biota Consideration shoud be given to the variety of biota that may be present when responding to oi spis, whether conducting burns or not, incuding: birds, especiay when nesting; sensitive pant species during growing seasons; burrowing and nesting animas when not dormant; migrating species and those which are trying to use a spi area for foraging and feeding; and the impact of smoke pume particuates on neighbouring habitats. The use of NEBA during oi spi contingency panning can hep to evauate factors such as those isted above in advance of a spi. Rapid oi remova by ISB can imit and/or prevent exposure to the oi. Burn panning shoud account for: oca widife, e.g. consideration shoud be given to scaring (hazing) operations; and protected species, which shoud be taken into account during burn design and execution; protected species may aso require speciay trained and icensed persons. It shoud be recognized that some terrestria habitats need fire as part of their ife cyce, e.g. some pines for propagation, and many grassands. Soi heating Soi heating has the potentia to affect vegetation through changes in soi property and damage to pant structures beow ground, such as roots and tubers. Damage to, and mortaity of, soi microorganisms and vegetation ces is expected above a temperature threshod of 60 C. In addition to the depth and degree of soi heating, the effects of fire on vegetation are aso dependent on the properties of different species, such as their rooting depth and sensitivity to heating. To improve the abiity to assess the potentia outcomes of ISB, information on the effects on pants and animas, and on the fire regimes of pant communities in the USA is avaiabe from the Fire Effects Information System (FEIS) and may be appicabe for other ocations with simiar pant communities. The FEIS database is avaiabe at Observations of intense energy reeased by faming combustion of petroeum fues during ISB suggest severe soi heating. However, the heating that resuts from the transfer of heat from the faming combustion zone into the soi beow is infuenced by severa factors incuding soi moisture. Research has shown that a sma percentage of tota energy emitted during burning is transferred downward into the soi, and when soi moisture is present, temperatures are imited to ess than 100 C unti this moisture is either transported out of the soi or is moved ower in the soi profie. The resuts of aboratory oi burns on soi cores demonstrate the effects of soi water on heat transfer to and within soi (see Figure 2 on page 20). Maximum soi surface temperatures were infuenced by the eve of water saturation; however, with the exception of temperatures resuting from one diese-saturated soi treatment, maximum soi temperatures at depths greater than 2 cm were ower than 60 C due to the high soi moisture content. The resuts support the use of ISB conducted over a range of high soi moisture eves. 19

22 IPIECA IOGP Figure 2 Laboratory oi burn data showing the effects of soi moisture on soi heating Source: Reardon, Weather conditions Some weather conditions can infuence burn panning and execution due to safety and PM 2.5 exposure concerns, for exampe an air temperature inversion, either present or forecast, which constrains the rise of a smoke pume and the diution of pume constituents. The photograph beow shows the effects of windy conditions and an inversion on a smoke pume, which moved ateray aong the ground for about a kiometre. A smoke pume moving aong the ground due to atera winds and a temperature inversion. Environment Canada Another exampe is a weather front that is forecast to move into a spi area within the next 12 hours; such a phenomenon can resut in rapidy shifting winds (speed and direction) or precipitation. Depending on the intended scae and duration of the burn, it may therefore be advisabe to compete the burn in advance of the weather front to eiminate potentia compications arising from rain or snow on the sick, the impact of winds on fire contro, and concerns regarding smoke pume trajectories near sensitive popuations. 1 Reardon, James, Forester at US Forest Service s Fire Laboratory in Missoua, Montana. Persona communication on resuts from soi core burns conducted for the American Petroeum Institute. 20

23 CONTROLLED IN-SITU BURNING OF SPILLED OIL Panning a burn Every ISB shoud be preceded by the preparation and approva of a burn pan which describes, at a minimum, the spi circumstances, the intended burning activities and pertinent safety precautions. A genera pan or tempate burn pan can be prepared in advance that contains as much of the information as practica from Tabe 6 to aid rapid preparation of an incident-specific burn pan. Tabe 6 Generic burn pan content Genera content Objective for burn and expected resuts Burn site physica and ega description with maps and photos: spi circumstances and oi weathering state hazards or concerns in burn area widife of concern in burn area * Responder Team assignments and contact information Equipment and suppies: ignition** and fire contro vehices/ vesses air support PPE toos for mop-up and cean-up Firebreak design, ocation and creation, pus perimeter watch Information on smoke management and pume trajectory prediction Pan preparation date and approva signature(s) Pan components Communications pan, incuding oca fire department contacts: key agency personne pans for pubic notices Ignition pan Heath and Safety Pan, incuding: fire contro/ extinction (if needed) escape pan for responders with map(s) evacuation pans for nearby residents navigation rues for on-water vesses, and traffic contro for on-and ocations A go/ no-go checkist Surveiance and monitoring pan Post-burn activities: mop-up cean-up and residue recovery * This may require the writing and utiization of a Best Management Practice (BMP) for the widife/species invoved. For exampe, see: ** refer ASTM F (2013): Standard Guide for In-Situ Burning of Spied Oi: Ignition Devices. Equipment, vesses and vehices for the burn crew Sufficient equipment, vesses and/or vehices shoud be avaiabe for the ISB fire crew to enabe them to respond to any potentia incident, incuding the possibiity of escaped fire in mutipe directions. During a and or onshore burn, at east two individuas shoud be in each vehice, and their movements monitored from a safe ocation. Crew members shoud carry shoves, rakes and speciaized snuffer toos. After the burn operation has been competed, the recovery of residue may require other toos and containers for coection and disposa. Smoke management The possibe impacts of the smoke shoud be estimated and considered. Smoke from a burn pume can be managed by decreasing the size of fires, burning under different wind directions, and during different times of day. 21

24 IPIECA IOGP Evacuation and safety zone As a safety precaution, an evacuation pan and safety zones shoud be identified to support the potentia evacuation of members of the pubic from the areas surrounding the panned fire. The pan shoud be sufficient to cover a worst-case scenario. One rue of thumb is that a safety zone shoud be arge enough so that the distance between the firefighters and fames is at east four times the maximum fame height. Another rue of thumb is that an evacuation zone in the downwind area must be a minimum of 10 times the ength of the downwind distance of the fire area, or a minimum of 1.5 kiometres (one mie). The upwind evacuation distance is the ength of the downwind distance of the burn area. Prior to the commencement of any burns, the evacuation zone(s) shoud be ceary communicated and briefed to a personne working in the burn area. Firebreaks A firebreak shoud be estabished around any and or shoreine burn to protect the surrounding area from potentia spreading fire. The width and ength of a break depends on terrain, wind, soi and vegetation moisture, and pant height. A minimum width is about 6 m (15 20 feet). There are de facto firebreaks in on-water operations, i.e. vesse set-back (tow) distances and abiity to reease booms. The cacuator for estimating firebreak width for a downwind firebreak is shown in Figure 3. Since the downwind width of a firebreak is more than the minimum upwind distance, the fire area and its firebreaks wi form a quadriatera shape. Figure 3 Firebreak width versus wind speed for burns Various situations and approaches exist for creating a firebreak on and or shores, incuding: an aready burned area with itte to no oi or vegetative fues; mowed and/or wet and; natura topography changes (such as rivers); tied ground; roads; and firebreak construction using a budozer, grader, etc. 22

25 CONTROLLED IN-SITU BURNING OF SPILLED OIL US Nationa Park Service Environment Canada Left: a firebreak created by mowing a fied, and the burning of a pipeine spi in winter where a snowcovered road provides a firebreak. Firebreaks for on-water burns are primariy safety setback distances between the pair of vesses towing the fire booms and from any adjacent vesses. See the Bibiography on page 39 for sources of information on and burns and firebreak design. Fire contro A pan and resources must be assigned to address the possibiity that fire coud escape beyond the panned burn site. For on-and and onshore burns this may incude detais of firefighting resources, the provision for remova of un-oied debris, and the estabishment of firebreaks. One technique used for on-and burns is to spray or food water to wet the intended burn site. This can aso assist in ifting oi from the and surface for remova by burning. For on-water burns, the most common means of fire contro is the reease of one end of a towed fireboom to enabe the sick to spread and thin and, by so doing, ower the concentration of ignitabe vapours. Another option is to instigate boom faiure for the same effect (e.g. by increasing tow speeds). An option for smaer-scae effect is for a vesse to rapidy transit near the boom and burning sick such that its bow wave disrupts the adjacent sick and the sustainabiity of the burn. Far eft: a water tanker is ready to provide fire contro. US Nationa Park Service Minnesota Poution Contro Agency Near eft: aeria spraying of fire retardant in advance of an inand burn. 23

26 IPIECA IOGP Ignition pan The ignition pan shoud describe the method(s) of ignition, ignition equipment, site access, the ine of ignition and ocation, safety zones, and the time and rate at which ignition is to be carried out. The above items appy to and, onshore and on-water burns. The direction of approach for ignition wi be infuenced by wind and current direction when on water, whie infuenced by wind, terrain sope and vegetation when on and. The drip torch is the most frequenty used method of igniting on-and burns (see photograph on the eft). A fare attached to a container of geed fue is the most frequenty used method of igniting on-water burns. Using a drip torch to ignite a prescribed burn. US Nationa Park Service Impementing a burn The conduct of ISB operations must meet reguatory requirements. Different eves of government may aready have procedures in pace for the approva of prescribed burning. An ISB pan and its execution shoud be coordinated with, or inked to, reevant prescribed burning pans in a particuar jurisdiction. Pre-burn safety briefing Near right: exampe of a foating handhed igniter using a marine fare, diese fue and a geing agent. Far right: the tip of a fare is used to ignite oi as frozen soi warms. In advance of every burn, there shoud be a safety briefing for in-fied responders. Such briefings usuay aim to provide the most recent information on weather status, spi status and ignition pans, together with communications and emergency reminders. Ignition Upon a signa from the burn boss, the ignition crews wi begin their task of appying a heat source to a sick to begin the burn. The photographs beow show ignition for a spi on water (eft) and a spi on and (right). Stabe emusions can be very difficut to ignite because the water in the oi wi act as a heat sink; consequenty, a higher amount of energy is needed to heat and vaporize the oi before burning can be sustained. Eastec Inc. US Nationa Park Service US Nationa Park Service 24

27 CONTROLLED IN-SITU BURNING OF SPILLED OIL Burn monitoring The fire shoud be monitored visuay and with the use of particuate monitors commensurate with the scae of the spi and burn, and the weather conditions. Photographs using GPS, and timeannotated photographs are hepfu to document the progress of burn operations. Patros shoud be conducted around firebreaks, with appropriate caution, to assess fire contro. Monitoring of on-and burns can be carried out in vehices or from aircraft. Monitoring of on-water burns can be carried out from vesses or from aircraft. Particuate monitors can be fixed/mobie or ground/pume eve. See Operationa monitoring for safety and burn contro on page 34. Extinguishing the remaining fames post-burn, during mop-up operations. Mop-up or site cean-up A check and cean-up of a burn site is made after a burn. This incudes wetting any smoudering spots or potentia fare-up sites. Any heavy oi burn residue that is deemed to have the potentia to suppress future revegetation shoud be noted for post-burn attention. This step is more important for on-and and onshore burns because of the potentia for fire fare-up from sti burning or smoudering vegetative fue and remaining spots of oi. US Nationa Park Service Post-burn actions Severa activities may be conducted, as required, after the concusion of burn operations in an oi spi response. Key among these are reporting, emergency site stabiization, post-burn monitoring for habitat recovery, and recovery aid through rehabiitation. Operationa summary reports Exampe photodocumentation of a burn site. Summary reports are a stipuation of most burn pans and woud be provided to the approving government agency/agencies. Such reports contain a summary of site conditions prior to the burn, documentation of burn execution, estimates of oi remova, observations of fire behaviour (of specia interest for on-and or shoreine burns), and detais of any oss of fire contro and commensurate actions to regain contro. Operationa summary reports are often accompanied by photographic documentation. For exampe, in the photograph on the right, the oied area that resuted from a pipeine spi is outined in yeow, and the pipeine route is indicated in red. The detai in a burn summary report shoud refect the scae of a spi and the compexity of the burn. Jacqui Miche, RPI 25

28 IPIECA IOGP Emergency stabiization Emergency stabiization after an on-and or onshore burn invoves any immediate restorative action that may be required for a burn area to ensure that there is minima impact on drainage patterns, soi conditions and vegetation. This activity reates ony to short-term needs to stabiize and or shoreines unti further restoration can be conducted or unti the area recovers naturay. This step does not appy to on-water burns. Post-burn observations and recovery monitoring Depending on the scae of a spi and subsequent and or onshore burn, the burn area shoud be monitored to ascertain the effectiveness of the oi remova and to observe progress with revegetation and re-estabishment of the habitat for an agreed-upon time after competion of the burn. Periodic visits to ascertain and document recovery are recommended. If an area is sow to reestabish, seeding or other forms of rehabiitation may be desired. Post-burn observations after an on-water burn are focused primariy on estimating the degree of oi remova and determining the practicaity of any residue recovery. Rehabiitation Rehabiitation is a onger-term activity to faciitate restoration of an inand or onshore burn area, which may be agreed to in a burn pan or afterwards (up to three or even five years). This incudes restoring vegetation and soi or drainage patterns on a onger-term basis, e.g. by seeding, adding soi conditioners, modifying drainage patterns, etc. This step does not appy to on-water burns. The burn area shoud be surveyed for any dense residue covering areas of vegetation. If residue is found that may inhibit the recovery of vegetation, it shoud be treated, recovered or tied. Soi amendments and re-seeding may be desired. The photographs beow and on page 27 show the situations before a burn, and afterwards/during post-recovery monitoring subsequent to a spi, at three different ocations. Right: (a) the vegetation on a sough before a burn; and (b) the vegetation on the same sough one year after the burn. (a) (b) Jacqui Miche, RPI Jacqui Miche, RPI 26

29 CONTROLLED IN-SITU BURNING OF SPILLED OIL (a) (b) Left: (a) aeria view of a marsh spi resuting from the overfow of a setting pond; and (b) an aeria view of a burn on the same marsh. NOAA NOAA (a) (b) Left: (a) the surface of a marsh as the burn is extinguishing; and (b) the surface of the same marsh three weeks post-burn. NOAA NOAA Burn residue The residue from a burn consists of partiay burned oi, oi depeted of voaties, and/or precipitated soot. It appears simiar to weathered oi of the same type and is typicay viscous and dense (see exampes beow). Residue excudes unburned oi. The residue in the photograph on the right was estimated to be around 20 kg or about 0.05% of the origina oi amount. The density of burn residue depends on how heavy the origina oi was and the competeness of the burn. An efficient on-water burn of a heavier crude oi wi produce a dense residue which coud sink and pose a threat to benthic species from smothering. However, sinking is rare and has ony been recorded in a few burns wordwide. Resuts from severa tests have shown that burn residue is ess toxic to aquatic biota than weathered ois. Far eft: residue from a fue oi burn on snow and ice. Near eft: residue in a boom apex after a 50-tonne burn. NOAA Environment Canada 27

30 IPIECA IOGP The decision to recover residue mechanicay or eave it to degrade naturay depends on the tota quantity of residue, whether it is dense enough to sink (if ISB was conducted on water), and where it is expected to go if it is not recovered. Other considerations incude the immediate avaiabiity of equipment and personne, as these might aready be depoyed in other recovery efforts, and the conditions for safe residue-recovery operations. Residue recovery considerations can be part of an overa ISB decision-making process using NEBA. Options for the recovery of burn residue incude the foowing: Depending on the quantity, residue coud be mechanicay recovered or transferred using either a vacuum suction system or a submersibe pump, or be manuay transferred with shoves and buckets. An on-water option is to herd the oi residue into one area using pumps or water hoses depoyed from a sma boat. Once herded, it may be possibe to re-ignite the residue or to ignite it aong with newy coected oi to further reduce the voume of residue to be recovered. Residue on water can aso be coected in a backup boom, and recovered using sorbents or skimmers suitabe for heavy oi. On and, residue is more readiy recovered using mechanica means. It may be preferabe to eave residue in pace after burns in habitats that are sensitive to tramping (e.g. wetands). It is possibe for unburned oi to remain after a burn and, if present in sufficient thickness and quantity to support ignition, this oi coud be subsequenty burned. 28

31 CONTROLLED IN-SITU BURNING OF SPILLED OIL ISB equipment Two main types of equipment are needed for ISB: an ignition system (i.e. the device itsef, together with an associated carrier or auncher if appicabe) and, for spis on water, a containment boom. Ignition devices A variety of ignition devices and methods have been used to ignite oi sicks. Many of the methods used are modifications of ignition devices used for other purposes. In genera, ignition devices must meet two basic criteria: 1. They shoud be safe to use. 2. They shoud be capabe of producing sufficient heat to ignite oi vapours from a sick. Heicopter undersung ignition devices Heicopters are sometimes used for transporting ignition devices. Often referred to as heitorches, these undersung devices dispense packets of burning, geed fue. This type of igniter was designed for the forestry industry and has been used extensivey for forest firefighting. Specia training is recommended for piots expected to hande heitorches. Two heicopter-based systems are shown beow. Far eft: a heicopter with empty torch tank detached prior to its return to base. Near eft: a heicopter carrying an undersung drip torch and reeasing geed fue in fight. Cean Caribbean and Americas OSRL Handhed and mobie patforms for igniters Handhed ignition devices are many, and extend from the very simpe (e.g. matches) to the compex (undersung drip torches, fame throwers, and pastic spherica device aunchers). Handhed devices are avaiabe for igniting and burns, as shown in the photographs at the top of page 30. Caution must be exerted in igniting materias at cose proximity, especiay if voatie components are present. Gasoine or ight crude ois shoud not be ignited at cose proximity. Furthermore, it shoud be noted that the spread of fire through a vapour coud, such as those that arise from gasoine or simiar fues, can be as fast as 50 m/s (100 knots). 29

32 IPIECA IOGP Near right: a member of an ignition team igniting a prescribed fire by fare gun. Far right: use of a power torch to ignite a prescribed burn. US Nationa Park Service Nationa Widfire Coordinating Group Mobie aunch patforms for ignition devices on and incude vehices or rotary wing aircraft. The photograph beow right iustrates a side-mounted chute designed to reease pastic spherica igniters from a heicopter. These igniters are fied with potassium permanganate; on reease, they are injected with gyco which reacts with the potassium permanganate to create an exothermic reaction for ignition. After a second deayed ignition as the two constituents react, a sustained fame is produced which ast for approximatey two minutes. Near right: a-terrain vehice (ATV) carrying geed fue for reease from a drip torch aong a designated ignition ine. Far right: a sidemounted auncher for depoying pastic spherica igniters for aeria ignition. Nationa Widfire Coordinating Group US Nationa Park Service Non-commercia ignition devices Simpe and informa ignition methods such as oi-soaked paper, rags or sorbent have been used to ignite oi at actua and test spis. A variety of handhed igniters have been devised for igniting oi sicks. These devices: can be thrown into a sick from a vehice, vesse or heicopter; often have deayed ignition switches to aow enough time to throw the igniter and, if required, aow it to foat into the sick; and use soid propeants, geed fue, geed kerosene cubes, reactive chemica compositions or a combination of these, and burn for 30 seconds to 10 minutes at temperatures ranging from 1,000 to 2,500 C. 30

33 CONTROLLED IN-SITU BURNING OF SPILLED OIL It shoud be noted that diese oi is much preferabe to, and safer than, gasoine for soaking materias or for use as a base for the geed fues in handhed igniters. An exampe of a handhed igniter, which has been used during severa ISB tests, is iustrated in Figure 4, beow. It consists of a pastic botte fied with geed gasoine or diese fue. The botte and a standard 15-cm marine handhed distress fare are secured side by side within two poystyrene foam rings. The fare is it and the device is thrown into the sick, where it burns for approximatey 60 seconds before meting the pastic botte and ighting the geed gasoine, which in turn ignites the oi. Figure 4 An igniter constructed from a pastic jug and fare Source: Environment Canada A simiar device to that shown in Figure 4 was used to ignite the burns during the Macondo spi response. Such devices, which are reativey easy to make and to depoy, are shown in the photographs beow. US Coast Guard US Coast Guard Far eft: one of the igniters used in ISB operations during the Macondo spi response. Near eft: ighting the fuse (fare) of an igniter before reeasing the device onto the water. 31

34 IPIECA IOGP Fire-resistant booms The primary requirement for a containment boom (and its components) used in ISB operations is the abiity to withstand heat for ong periods of time. Fire-resistant booms are generay designed to survive mutipe burns, after which they are then disposed of, or refurbished. Severa types of fire-resistant boom designs are shown in Figure 5 beow. To ensure that the boom used in an ISB operation wi be abe to withstand mutipe burns, a standard test has been devised by ASTM to assess durabiity. The minimum standard is a five-hour test invoving three 1-hour burning periods with two 1-hour coo-down periods between the burning periods. Figure 5 Types of fire-resistant booms 32

35 CONTROLLED IN-SITU BURNING OF SPILLED OIL The containment abiity of a fire-resistant boom is aso important. Studies have determined the tow speeds at which booms begin to ose oi ( first oss ) and the speed at which a continuous, significant oss occurs ( gross oss ). The rate of oss of oi can aso be determined at specific tow speeds, as can the tow speed at which the boom physicay fais, i.e. the speed at which the boom becomes submersed or suffers structura damage. Detais on depoyment and towing are provided in Appendix 2. Conventiona booms A conventiona boom cannot usuay contain burning oi as the construction materias wi either burn or met, compromising the boom s abiity to contain oi. Conventiona booms can be used to corra a sick unti a fire-resistant boom can be obtained, or they can be used as side extensions to a fire boom over onger towing distances. Support vesses for ISB on water Vesses pay an important roe in a successfu ISB operation. Vesses are required to bring equipment and personne to the burn site, to tow booms and to carry monitoring equipment. Barges and sma boats may aso be required for standby fire safety and monitoring operations, as we as being used for residue recovery and for storing equipment and residua oi. A sufficient number of vesses must be avaiabe to transport and depoy the ength of containment boom required at the burn site. Support vesses shoud aso be appropriate for the task: Vesses must have a arge enough deck space to carry the boom, as we as any equipment and materias required for handing the boom. They must aso be abe to move steadiy and manoeuvre effectivey at a sow speed (<0.5 m/s). A vesse with a ow freeboard enabes easier access to the water surface and is recommended for recovering burn residue. A barge or anding craft used in conventiona oi spi response is idea. Support aircraft for ISB Aeria surveiance aong the burn perimeter. Aircraft pay an important roe in successfu ISB operations. Fixed and rotary wing (heicopter) aircraft can be used for surveiance and aeria photodocumentation of a spi site, and to provide an ignition patform, aid sick targeting for vesses or other aircraft, support burn extinguishing operations and carry monitoring equipment. For a aircraft operations, reiabe air-to-ground communications are essentia. Minnesota Poution Contro Agency 33

36 IPIECA IOGP Operationa monitoring for safety and burn contro Monitoring heps to provide information on the effectiveness of a burn, and is an aid for vigiance regarding the safety of nearby responders and observation of fire contro. Tabe 7 summarizes the key aspects of a burn operation that shoud be monitored. Tabe 7 Aspects to be monitored during ISB operations Aspect Targets of observation Interpretation Fire safety Fire boom containment integrity Burn effectiveness Burn emissions Proximity of personne to the burn Fire contro and movement Loss of a boom s abiity to contain the sick Oied area ignited and burning over time Particuates Danger to humans, infrastructure and amenities Provide eary warning to vesse operators and responders Efficiency of oi remova; voume of oi remova Monitor human exposure Exposure of responders to heat The safety and heat exposure imitations for responders must be thoroughy understood. A rue of thumb for responders is to stay back from a fire at a distance equivaent to four times the maximum fame height. The fame spreading rate is usuay about m/s; however, this rate can increase with wind. Other considerations incude: On and, fires can move rapidy where combustibe materias such as trees and grass are nearby. An adequate firebreak shoud be in pace prior to ignition to provide fire contro and protection against heat. Crews onboard vesses invoved in tow operations can be in danger of being exposed to fire or fames if the fire shoud move up the boom. This coud occur if thick patches of oi are encountered and the fame spreads aong these thicker patches. The fames woud not spread towards the towing vesses if the boom is moving at a speed of at east 0.4 m/s (0.7 knots) in an upwind direction. In highy variabe winds, caution must be taken to ensure that thick concentrations of oi are not encountered at ow boom-tow speeds. The behaviour and distribution of ISB emissions The primary heath concerns reated to ISB arise from the emissions produced by a burn. Empirica measurements of emissions revea that their concentrations dissipate rapidy in the atmosphere and as the distance from the burn site increases. Ensuring that the burn remains at the minimum distance away from popuated and sensitive areas wi hep to mitigate safety concerns. Emissions eves and safe distances downwind can be estimated for burns of various sizes and types. For exampe, a crude oi burn (500 m 2 ) woud not generate concentrations of emissions that exceed heath imits beyond around 500 m from the fire. The key combustion products that resut from petroeum burns are predominanty carbon dioxide and water, and by-products, i.e. particuates (soot), organic compounds and gases. 34

37 CONTROLLED IN-SITU BURNING OF SPILLED OIL Tracking the behaviour of burn emissions is an important aspect of ISB monitoring. The most important emissions are the soot partices (PM): these rise and are then are precipitated back to the ground (Figure 7). It is estimated that before a pume traves 1 km, haf of any partices are precipitated downward (depending on wind speed). Some PM remains aoft with a smoke pume for a ong time. The pume itsef is not dangerous to humans as ong as it rises in atitude and does not ead to exposure eves of concern. Figure 7 Behaviour of different combustion emissions in a burn pume a) Particuates aong with adsorbed organics, e.g. PAHs, rise and are then precipitated downwind. b) Water vapour and ight gases rise and are widey transported and diffused. c) Carbon dioxide and other heavy gases rise and then sowy sink, and may cyce through the fire. d) Organic gases, such as VOCs and carbonys are widey diffused and diuted. Merv Fingas Particuate matter ISB produces particuate matter, which is the primary emission of concern from an oi fire with respect to human heath. Particuate matter is distributed exponentiay downwind from the fire. Concentrations at ground eve (1 m) can be above heath concern eves (35 μg/m 3 ) even as far downwind as 500 m from a sma crude oi fire. Of greatest concern are the smaer, or respirabe, particuates, i.e. the PM 2.5 fraction (partices of size ess than 2.5 μm). It shoud be noted that these partices are often not visibe as a smoke pume even if concentrations are above threshod eves. 35

38 IPIECA IOGP Safe distances Sufficient data are avaiabe to predict concentrations for more than 150 individua compounds and for a the major chemica compound groups. The data have been coected with wind speeds between 2 to 5 m/s (4 to 10 knots) and with no inversions. The prediction equations for severa common emission groupings and specific compounds are given in iterature referenced in the Bibiography on page 39. Figure 8 Safe downwind distances for burn areas of varying sizes Safe distances downwind from a crude oi burn (based on PM 2.5 concentrations) have been estimated from severa on-water test burns, during which winds varied from ~2 to 10 m/s (~4 to 20 knots) see Figure 8. A safe operationa distance is defined as the downwind distance after which no particuate respirators woud be needed. Athough the resuts are based on data from on-water burns, the distance estimates are aso appicabe to on-and burns, at the various burn sizes. However, it shoud be noted that: higher winds coud increase these distances whie ower-speed winds woud decrease the distances; and these distances are not appicabe during inversions because the smoke pume coud be forced to ground eve. Monitoring and samping for emissions A we-panned monitoring programme, in which data are recorded before, during and after a burn, wi hep to document the burn operation and hep to answer any questions arising after a burn operation. At the minimum, monitoring and samping shoud incude: visua monitoring of the smoke pume, its trajectory and its possibe impacts on humans or sensitive environments (time and physica ocations shoud be documented); and monitoring of 2.5 μm (PM 2.5 ) particuates downwind of the burn at a receptor height of 1.5 m, and in particuar between 1 to 3 kiometres downwind of the burn, and at the receptor height, at any potentia human impact ocations. 36

39 CONTROLLED IN-SITU BURNING OF SPILLED OIL Shifting weather conditions can dramaticay change the precipitation of particuate matter in a pume. In some cases, a pume can drop to ground eve. Weather officias shoud be consuted for forecasts of weather and wind, and for information on the potentia for atmospheric inversion. Visua monitoring Visua monitoring of the trajectory of a smoke pume and its passage over and, popuation centres, and other points of concern shoud be noted, timed and recorded. This information is beneficia for answering questions on any potentia for exposure to emissions from an in-situ burn. The prime areas of deposition shoud be surveyed after a burn to check for soot deposits. If soot is found, it shoud be samped for possibe anaysis if deemed necessary. Rea-time particuate monitoring If required by reguators, or if a forecasted burn pume trajectory indicates the potentia for exposure of sensitive popuations, rea-time monitoring of emissions shoud be performed downwind of the fire and at a point cosest to popuated areas. Concentrations of partices downwind can vary over time, and a reading can exceed the recommended maximum vaue on one occasion and then be at baseine vaues the next. Background vaues shoud be measured and subtracted from the observed vaues. The instrument readings shoud be eectronicay recorded and time-weighted averages cacuated from the recorded and corrected data. Some instruments provide running average readings which are appicabe to rea-time use. For monitoring of particuate matter, it is generay accepted that the concentration of partices having diameters of 2.5 μm or ess (PM 2.5 ) shoud be ess than 35 μg/m 3 over a 24-hour period. This is a standard used by severa nationa authorities. There are severa methods for coecting and anaysing sampes to evauate emissions from ISB. See the Bibiography on page 39 for sources of information on samping emissions. Air quaity monitoring station at Great Smoky Mountains Nationa Park, North Caroina and Tennessee US Nationa Park Service 37

40 IPIECA IOGP Operationa monitoring The purposes of operationa monitoring are: to guide successfu ignition; to provide documentation of burn operations and burn progress; to estimate the area of oi burning at specific time intervas to estimate the tota amount burned (The nomogram in Appendix 1 can be used to estimate the area of a burn and the voume of oi removed. Each burn ocation shoud be recorded at approximatey 10-minute intervas for sma, short burns. Larger, onger burn can have onger intervas. Photographs shoud be taken of burn operations at periodic intervas; use of a camera that has a time and GPS stamp is recommended); on and or shoreines to assure the safety of burn crews and their vehices; to track the trajectory of a smoke pume and its proximity to human habitation; and to enabe advance aerts for danger and take action, as necessary (for exampe to instigate an evacuation or to extinguish a burn eary); at sea to provide direction to the towing vesse crews to optimize the encounter rate with spied oi to increase the voume of oi coected in a fire boom for remova by ISB. At sea, two surveiance tactics shoud be considered: 1. aeria surveiance; and 2. surveiance from a arger vesse. There is a greater range of view from an aircraft than from a surface vesse; this may be advantageous when observing boom performance and burn operations. A arger, non-towing vesse can provide a good view of the tow operation from the water surface and coud be equipped with extra fire monitors for firefighting capabiity. Such a vesse aso provides a means of rescue if a towing vesse gets into difficuty. 38

41 CONTROLLED IN-SITU BURNING OF SPILLED OIL Bibiography Genera Aaska Regiona Response Team (ARRT) (2010). Chemica Countermeasures: Dispersants, Chemica Agents, and Other Spi Mitigating Substances, Devices or Technoogy. Annex F, Unified Pan, Aaska, 126 pp. ARPEL (2006). A Guide to In-situ Burning of Oi Spis on Water, Shore, and Land. Regiona Association of Oi and Natura Gas Companies in Latin America and the Caribbean. Environmenta Guideine November 2006, 47 pp. ARPEL (2007). In-situ Burning: A Ceanup Technique for Oi Spis. Regiona Association of Oi and Natura Gas Companies in Latin America and the Caribbean. Environmenta Guideine February 2007, 127 pp. ASTM (2013). ASTM F (2013), Standard Guide for In-Situ Burning of Spied Oi - Ignition Devices. ASTM Internationa, Conshohocken, PA. ASTM (in preparation). ASTM WK37324, Standard Guide for Evauation of ISB Effectiveness. ASTM Internationa, Conshohocken, PA. IPIECA-IOGP (2015). Response strategy deveopment using net environmenta benefit anaysis (NEBA). IPIECA-IOGP Good Practice Guide Series, Oi Spi Response Joint Industry Project (OSR-JIP). IOGP Report ITOPF (2011). Fate of Marine Oi Spis. Technica Information Paper No. 2. Internationa Tanker Owners Poution Federation Limited, London. Nationa Institute of Standards and Testing: compiation of references at: At-sea burns: genera references API (2015). Fied Operations Guide for In-Situ Burning of On-water Oi Spis. Pubication No American Petroeum Institute, Washington, D.C., 72pp. Arctic Response Technoogy (2013). In-Situ Burning in Ice-Affected Waters: State of Knowedge Report. Fina Report of the Arctic Oi Spi Response Joint Industry Programme. Prepared for IOGP. 293 pp. Arctic Response Technoogy (2013). In Situ Burning in Ice-Affected Waters: A Technoogy Summary and Lessons from Key Experiments. Fina report of the Arctic Oi Spi Response Joint Industry Programme. Prepared for IOGP. 67pp. ASTM (2013). ASTM F (2013), Standard Guide for In-Situ Burning of Spied Oi: Fire-Resistant Boom. ASTM Internationa, Conshohocken, PA. 39

42 IPIECA IOGP ASTM (2008). ASTM F , Standard Guide for In-Situ Burning of Oi Spis on Water: Environmenta and Operationa Considerations. ASTM Internationa, Conshohocken, PA. ASTM (2014). ASTM F , Standard Guide for In-Situ Burning of Oi Spis on Water: Ice Conditions. ASTM Internationa, Conshohocken, PA. Buist, I. A., Potter, S. G., Trude, B. K., Waker, A. H., Schoz, D. K., Brandvik, P. J., Fritt-Rasmussen, J., Aen, A. A. and Smith, P. (2013). In-Situ burning in Ice-Affected Waters: A Technoogy Summary and Lessons from Key Experiments. Fina Report Report from the Joint Industry Programme on reevant scientific studies and aboratory and fied experiments on the use of in-situ burning in iceaffected offshore environments. Fingas, M. (2011). ISB, Chapter 23 in Oi Spi Science and Technoogy. M. Fingas, Editor, Guf Pubishing Company, New York, pp Mabie, N. (2012). Controed ISB: Transition from aternative technoogy to conventiona spi response option. In Proceedings of the 35th AMOP Technica Seminar on Environmenta Contamination and Response, pp OSRL (2011). Offshore In-Situ Burn Operations Fied Guide: A guide to operationa and monitoring requirements for In-Situ burning at sea. Oi Spi Response Limited, 20pp. Burns: emissions API (in preparation). In-Situ Burning of Petroeum: Comparison of Emissions from burning of Petroeum, Petroeum-Derived Fues and other Fue types. American Petroeum Institute, Washington, D.C. Fingas, M. F. and Punt, M. (2000). ISB: A Ceanup Technique for Oi Spis on Water. Environment Canada Specia Pubication, Ottawa, Ontario, 214 pp. Fingas, M. F., Lambert, P., Wang, Z., Li, K., Ackerman, F., Godthorp, M., Turpin, R., Campagna, P., Nadeau, R. and Hitabrand, R. (2001). Studies of Emissions from Oi Fires. In Proceedings of the Twenty- Fourth Arctic and Marine Oi Spi Program Technica Seminar, Environment Canada, Ottawa, Ontario, pp On-and burns: genera API (2015). Fied Operations Guide for In-Situ Burning of Inand Oi Spis. Pubication No American Petroeum Institute, Washington, D.C., 81 pp. Prescribed burning: genera US Department of Agricuture, Forest Service (2006). Prescribed Fire Case Studies, Decision Aids and Panning Guides. In Fire Management Today, Vo. 66, No. 1, Winter 2006, pp Okahoma State University (2009). Okahoma Prescribed Burning Handbook. Document ref. E Last updated pp. 40

43 CONTROLLED IN-SITU BURNING OF SPILLED OIL Southeast Queensand Fire and Biodiversity Consortium (2002). Fire Management Operationa Manua: Guideines for panning and conducting fue reduction and ecoogica burns on your property. Queensand, Austraia. 102 pp. Fire Paradox (website). Handbook to Pan and Use Prescribed Burning in Europe. Fire Paradox a European Commission Project. US Department of Agricuture, Forest Service (2006). Smoke Issues and Air Quaity. In Fire Management Today, Vo. 33 No Firebreaks Government of Western Austraia (2011). Firebreak Location, Construction and Maintenance Guideines. Fire and Emergency Services Authority of Western Austraia, 28 pp. FESA%20Firebreak%20Guideines_std.pdf Burning in marshes API (2003). Recovery of Four Oied Wetands Subjected To In Situ Burning. Pubication No. 4724, Washington, D.C., June pp. ASTM (2010). ASTM F (2015), Standard Guide for In-Situ Burning of Oi Spis in Marshes. ASTM Internationa, Conshohocken, PA. Safety and monitoring API (in preparation). In-situ Burn Guidance for Safety Officers and Safety and Heath Professionas. American Petroeum Institute, Washington, D.C. BP (2013). Controed ISB Operations Monitoring Handbook. Prepared by Midinx Consuting Inc. for British Petroeum, Houston, Texas. IPIECA-IOGP (2008). Heath aspects of work in extreme cimates. IOGP Report 398. Effects on animas and pants API (1999). Compiation and Review of Data on the Environmenta Effects of In Situ Burning of Inand and Upand Oi Spis. Pubication No American Petroeum Institute, Washington, D.C. US Department of Agricuture, Forest Service (website). Fire Effects Information System (FEIS). Modes US Department of Agricuture, Fire, Fue, and Smoke Science Program : US Department of Agricuture, First Order Fire Effects Mode (FOFEM) : 41

44 IPIECA IOGP Appendix 1: Estimation of the amount of oi burned and the burn efficiency At sea, the area of oi burning inside a boom is recorded aong with the burn duration using a tempate simiar to that shown Figure A1 on page 43. These detais can be used to cacuate the amount of oi burned. The area can be cacuated from Figure A1 in conjunction with Tabe A1. Burn rates are isted in Tabe 3 on page 8. The procedure is as foows: Using the charts of the boom fis recorded during the burn, the fi area is estimated using Tabe A1. The time over which burning took pace for this fi eve is then mutipied by the burn rate for that type of oi (see Tabe 3) to give the amount of oi burned. A times and boom fi amounts are cacuated this way and then summed; the fina resut provides an estimate of the amount of oi to be burned or consumed. The voume of oi burned can be cacuated using Equation 1, as foows: Equation 1: Burn voume = Area x time x rate x conversion factor where the conversion factor for metric units is to give a voume in m 3, and in US customary units is to yied a voume in barres (area in square feet, but burn rate in mm/minute). Exampe: During a burn, nomograms of the type shown in Figure A1 showed that, for 21 minutes, there was remova of approximatey one haf of a 150 m boom fied with medium crude oi. Using Tabe A1, it can be seen that the area is about 1,220 m 2, and Tabe 3 indicates that the burn rate is about 3.5 mm/min. The amount burned is thus cacuated as: 1,220 x 21 x 3.5 x = 89.7 m 3 (560 barres). Burn efficiency is measured as the percentage of oi removed compared to the amount of residue eft after the burn. The burn efficiency, E, can be cacuated using Equation 2 (beow), where v oi is the initia voume of oi to be burned and v of is the voume of residua oi remaining after burning: Equation 2: v oi v of E = v oi The initia voume of oi, v oi, can be estimated in a number of ways: If the spi source is known, as in the case of a vesse or storage depot, the voume spied can be estimated from the tank size and the amount of oi remaining in the tank. In the case of an offshore rig, the discharge rate can be used to estimate the initia voume. This voume, combined with the sick area and an estimate of the average thickness of the oi, can then be used to estimate the voume of a sick. In the case of burning at sea using a containment boom, the amount burned versus an estimate of the residue can constitute the inputs to Equation 2. Spis on and or marshes cannot be estimated in the above ways since much of materia burned may be vegetation. 42

45 CONTROLLED IN-SITU BURNING OF SPILLED OIL Figure A1 Nomogram used to record burn areas and subsequenty cacuate burn areas Tabe A1 Boom fi-to-area conversions for a u-shaped boom a) Metric Units: Boom sizes = 150 m 50 m opening and a 200 m 66 m opening Degree of fi Length (m) Width (m) Burn area (m 2 ) Length (m) Width (m) Burn area (m 2 ) 3/4 three quarters , ,590 5/8 five eighths , ,860 1/2 one haf , ,170 3/8 three eighths ,530 1/4 one quarter /8 one eighth b) US customary units: Boom sizes = 500 ft 166 ft opening and a 700 ft 233 ft opening Degree of fi Length (m) Width (m) Burn area (m 2 ) Length (m) Width (m) Burn area (m 2 ) 3/4 three quarters , ,200 5/8 five eighths , ,900 1/2 one haf , ,900 3/8 three eighths , ,600 1/4 one quarter , ,800 1/8 one eighth , ,500 43

46 IPIECA IOGP Appendix 2: Boom depoyment and towing configurations Depoyment of booms for ISB The depoyment procedures for fire-resistant containment booms depend on the type of boom used. Water-cooed booms are typicay infatabe and can therefore be stored on, and depoyed from, a ree. However, these booms sometimes require a arge deck space for the proper instaation of the water-cooing equipment as the boom is removed from the ree. Stainess stee booms and thermay resistant booms are rigid and therefore need to be stored in sections within a container. They wi aso require deck space to connect the sections during depoyment. Because of their rigidity and weight, a winch or crane is normay required to assist in their depoyment. Booms can be damaged during depoyment and recovery. Care must be taken to ensure that the boom is moved sowy and handed carefuy. For exampe, the cinch and choker attachment of a crane can damage a boom and it is therefore better to use a web bet to ift the boom. The photographs beow show different boom depoyment methods. Near right: depoyment of a boom from the rear of a suppy vesse. Far right: depoyment of a fire-resistant boom using a crane. Eastec Inc. Desmi-AFTI Containment booms normay come in sections joined by a connector. Many fire-resistant booms are equipped with standard connectors or can accommodate adapters that can fit standard connectors. These connectors aow different types of booms to be joined together easiy and securey. If more than one type of boom is used for containment, the connectors on these booms shoud be checked first to ensure that they can be propery joined. The foowing is a typica procedure for depoying a boom in open water from a vesse, using a standard U configuration. The depoyment vesse situates itsef far enough downwind from the oi so that there is enough time to depoy the boom before approaching the oi. The depoyment vesse aigns itsef so that its bow is facing upwind. Before the first part of the boom is depoyed from the deck, a tow ine for the towing vesse is attached to the end. 44

47 CONTROLLED IN-SITU BURNING OF SPILLED OIL The boom is depoyed from the vesse stern so that the wind causes the boom to trai behind. When the ast section is depoyed, the end of the boom is attached with a towine to the depoyment vesse, which can then become one of the towing vesses. If another towing vesse is to be used, this towing vesse picks up the tow ine from the depoyment vesse. The tow ine at the other end of the boom is then attached to the second towing vesse. The second towing vesse heads upwind unti the proper U configuration is formed. Fire boom towing configurations The size of boom required for an in-situ burn depends on the amount of oi to be burned. In genera, the ength of boom used ranges from 150 to 300 m (500 to 1000 feet). Most commercia booms come in standard engths of 15 or 30 m (50 or 100 feet). Generay, the oi in the boom shoud fi no more than two-thirds of the area of the catenary, the typica U shape that a towed oi boom takes (Figure A2). Figure A2 Tow configurations that can be used to tow fire-resistant booms Based on information courtesy of Environment Canada 45

48 IPIECA IOGP An on-water in-situ burn within a fireresistant boom depoyed in the standard U configuration. Eastec Inc. Tow ines from tow boats shoud generay be at east 75 m (150 feet) ong. The boom shoud aways be towed into the wind so that smoke wi pass behind boats. As tow speeds are measured reative to the current, the boom may have to be towed very sowy or even downwind to maintain a ow enough speed reative to the current whie towing into the wind. In genera, booms shoud be towed at a speed of <0.4 m/s (<0.7 knots) to prevent the oi from spashing over the boom or becoming entrained beneath. Additiona considerations are described beow: The standard boom configuration consists of a ength of fire-resistant boom connected with tow ines to two vesses at either end of the boom to tow the boom in a catenary or U shape, as shown in Figure A2 (a). A tether ine or cross bride may be secured to each side of the boom severa metres behind the towing vesses to ensure that the boom maintains the proper U shape, as shown in Figure A2 (b). This tether ine or cross bride is usefu in maintaining the correct opening for the boom tow as we as preventing the accidenta formation of a J configuration. When using the standard U configuration, it can be difficut to ensure that the two towing vesses maintain the same speed. To overcome this probem and to increase contro over the boom configuration, three vesses can be used as shown in Figure A2 (c). One vesse tows the boom by puing from the centre using tow ines at each end of the U, whie the other two vesses pu outward from the ends of the boom to maintain the U shape. The tether ine can aso be attached to the vesses as shown in Figure A2 (d). The advantage of this method is that boat operators can detach the tether ine very quicky in the case of an emergency. If the oi is nearshore, a boom (or booms) can be used to divert it to a cam area, such as a bay, where the oi can be burned. An exampe of this method using two booms is shown in Figure A2 (e). Diversion booms must be positioned at an ange reative to the current that is arge enough to divert the oi, but not too arge that the current woud cause the boom to fai. The boom woud be hed in pace either by anchors, towing vesses or ines secured to the shoreine. The towing speed may have to be increased periodicay if a burn begins to fi more than twothirds of the boom space. If contained oi becomes entrained in the water coumn beow the boom, or spash over the boom, it wi resurface or poo directy behind the apex of the boom. This uncontained oi coud potentiay be ignited by the burning oi inside the boom or by ignited oi that spashes over the boom. 46