1、Designation: F1693 13Standard Guide forConsideration of Bioremediation as an Oil Spill ResponseMethod on Land1This standard is issued under the fixed designation F1693; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of la
2、st revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 The goal of this guide is to provide recommendationsfor the use of biodegradation enhancing agents for remediatingoil sp
3、ills in terrestrial environments.1.2 This is a general guide only, assuming the bioremedia-tion agent to be safe, effective, available, and applied inaccordance with both manufacturers recommendations andrelevant environmental regulations.As referred to in this guide,oil includes crude and refined p
4、etroleum products.1.3 This guide addresses the application of bioremediationagents alone or in conjunction with other technologies, follow-ing spills on surface terrestrial environments.1.4 This guide does not consider the ecological effects ofbioremediation agents.1.5 This guide applies to all terr
5、estrial environments.Specifically, it addresses various technological applicationsused in these environments.1.6 In making bioremediation-use decisions, appropriategovernment authorities must be consulted as required by law.1.7 This standard does not purport to address all of thesafety concerns, if
6、any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use. In addition, it is theresponsibility of the user to ensure that such activity takesplace u
7、nder the control and direction of a qualified person withfull knowledge of any potential or appropriate safety andhealth protocols.2. Terminology2.1 Definitions:2.1.1 aerobesorganisms that require air or free oxygen forgrowth.2.1.2 anaerobesorganisms that grow in the absence of airor oxygen and do n
8、ot use molecular oxygen in respiration.2.1.3 bioaugmentationthe addition of microorganisms(usually predominantly bacteria) to increase the biodegradationrate of target pollutants.2.1.4 biodegradationchemical alteration and breakdownof a substance, usually to smaller products, caused by micro-organis
9、ms or their enzymes.2.1.5 bioremediationenhancement of biodegradation.2.1.6 bioremediation agentsinorganic and organic com-pounds and microorganisms that are added to enhance degra-dation processes, predominantly microbial.2.1.7 biostimulationthe addition of microbial nutrients,oxygen, heat, or wate
10、r, or some combination thereof, toenhance the rate of biodegradation of target pollutants byindigenous species (predominantly bacteria).2.1.8 ecosystemorganisms and the surrounding environ-ment combined in a community that is self-supporting.3. Significance and Use3.1 The purpose of this guide is to
11、 provide remediationmanagers and spill response teams with guidance on bioreme-diation.3.2 Bioremediation is one of many available tools and maynot be applicable to all situations. This guide can be used inconjunction with other ASTM guides addressing oil spillresponse operations as well as options
12、other than bioremedia-tion.4. General Considerations for Bioremediation Use4.1 Bioremediation technologies attempt to accelerate thenatural rate of biodegradation. In situ, solid-phase, and slurry-phase represent the major bioremediation technologies used.These technologies may be unnecessary in tho
13、se cases in whichthe natural rate of biodegradation suffices. The use of adequatecontrols in preliminary field studies, or the results of previouslyreported studies, will assist in determining the extent to whichmicroorganism or nutrient amendments, or both, are necessaryto obtain the desired rate o
14、f degradation.1This guide is under the jurisdiction of ASTM Committee F20 on HazardousSubstances and Oil Spill Response and is the direct responsibility of SubcommitteeF20.13 on Treatment.Current edition approved April 1, 2013. Published May 2013. Originallyapproved in 1996. Last previous edition ap
15、proved in 2003 as F1693 96 (2003)which was withdrawn July 2012 and reinstated in April 2013. DOI: 10.1520/F1693-13.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States14.2 Bioremediation performance depends on the efficiencyof the petroleu
16、m hydrocarbon degrading indigenous microor-ganisms or bioaugmentation agents. Performance also dependson the availability of rate-limiting nutrients and the suscepti-bility of the target crude oil or refined product to microbialdegradation. As oil consists of hundreds or more compounds,many of which
17、 require different conditions or different micro-organisms to degrade, oil biodegradation should not be con-sidered a single process. Oil biodegradation should at leastconsider the aliphatics separate from the aromatic compounds.Other classes of compounds often degrade to a lesser degree,these class
18、es include resins, asphaltenes, large aliphatics andlarge aromatics (1, 2)2.4.2.1 In general, aerobic bioremediation systems degrade oilmore rapidly than anaerobic systems, and adequate aerationmay be the most promising approach in many cases.4.2.2 Numerous microorganisms, represented by hundredsof
19、species, are responsible for the degradation of the oil.Various texts describe the biodegradability and biodegradationrates of a variety of organic compounds present in oil (3, 4).4.2.3 The biodegradation of aliphatic and aromatic hydro-carbons in the absence of molecular oxygen is generally slowert
20、han under aerobic conditions. Anaerobic biodegradation hasbeen characterized under sulfate-reducing, nitrate-reducing andmethanogenic conditions (5, 6).4.3 Bioremediation must be conducted under the guidanceof qualified personnel who understand the safety and healthaspects of site activities.5. Back
21、ground5.1 Approaches to bioremediation for oil spill responseinclude biostimulation, the addition of nutrients, oxygen, heat,or water, or combination thereof, to stimulate indigenousmicroorganisms, and bioaugmentation, the addition of oil-degrading microorganisms, which may be used in combinationwit
22、h biostimulation (7-16). As a precaution, it should be notedthat nutrient components may be toxic or harmful to plants,animals, and humans, and that non-indigenous species mayalter the indigenous microbial ecological balance at leasttemporarily. Indigenous microbes have been found to be moreeffectiv
23、e than non-indigenous microbes (13-16). Water effluentnitrate levels, which can affect drinking water sources, shouldbe minimized to diminish risks of health issues. Similarly,excessive ammonium levels should be avoided because theycan affect fish and invertebrates, since many are immobile andcannot
24、 avoid the treated area. Therefore, nitrogen and othernutrient levels should be monitored. Instructions to ensuresafety and effective product use should be established by themanufacturer or supplier for each commercial microbialproduct, and specific instructions should be followed by theproduct user
25、.5.1.1 Biostimulation has been shown to enhance the biodeg-radation of terrestrial oil spills. Biostimulation uses the addi-tion of appropriate nutrients (for example, nitrogen,phosphorus, potassium, micronutrients, and so forth), oxygen,heat, or water, which may have been limiting factors. Ifmicrob
26、ial degraders of the target oil contaminants are presentin the soil or contaminated waters, these approaches usuallylead to increases in the rate of degradation. In some cases theremay not be a sufficient indigenous oil-degrading population tostimulate. This may be the case in environments in which
27、thedegrader population has not developed. Alternately, the toxicnature of the petroleum product may diminish or eliminatemicroorganisms. Also, the excavation of soil from anoxiczones and subsequent relocation to an oxygen-rich environ-ment may result in a lack of microbial degraders due to thedrasti
28、c change in conditions. The microbial response to bio-stimulation may include a lag period (weeks to months) for thegrowth or natural selection of degraders to occur.Microorganisms, as well as oil contaminants, should be moni-tored throughout the process to establish efficacy and safety.5.1.2 Bioaug
29、mentation may use commercial microbialproducts, on-site production of microbes from stock cultures,or laboratory isolation, characterization, and subsequent pro-duction of microbes from the particular site (or another sitesimilar in soil and contaminant characteristics). This approachmay increase so
30、il microbe concentrations rapidly. Microbesselected must be nonpathogenic and must metabolize the oilcontaminant(s), reducing toxicity. Growth requirements of themicrobes need to be well understood. Their growth rate iscontrolled by the limiting growth conditions of temperature,pH, nutrients, water,
31、 oxygen, the contaminated medium (soil,sludge, and water), and oil. Microorganisms as well as oilcomponents should be monitored to establish efficacy andsafety. Addition of non-indigenous microbes has not beenfound to be highly effective (13-16).5.1.3 While apparently safe and effective in the labor
32、atorysetting, genetically engineered oil-degrading microorganismshave only rarely been authorized for environmental release (forexample,17).5.2 There are several bioremediation technologies available.It is important to understand the potential use of these systemswhen assessing their applicability f
33、or full-scale implementa-tion. Costs are determined by the size of the site, soilproperties, type and level of oil contaminant(s), goals, timeallowed for attaining the goals, and testing requirements.5.3 In situ bioremediation occurs without excavation of thecontaminated soil. This technology relies
34、 predominantly on theenhanced degradation of oil by bacteria following the additionof nutrients, air, oxygen or oxygen-releasing compounds, andmoisture. This has usually been demonstrated through the useof indigenous microorganisms. Ground-water treatment maybe achieved simultaneously or through pum
35、p and ex situtreatment methods. Anaerobic biodegradation systems can alsobe promoted; however, their utility has been limited to date.Since soil is not excavated, volatile release is limited, and therisks and costs associated with excavation and treatment arereduced.5.3.1 Bioventing involves the int
36、roduction of air underpressure to the unsaturated zone of contaminated soil. Theprocess pulls or pushes air into the soil for use by the aerobicmicroorganisms. Although the purpose is to deliver oxygenrequired by the microbes, it may dry the soil and require the2The boldface numbers in parentheses r
37、efer to a list of references at the end ofthis standard.F1693 132addition of moisture. Furthermore, the flow of air will desorbsome of the more volatile components from the soil (forexample, gasoline-contaminated soil), and the exhaust gasesmay have to be treated. Successful treatment requires adequ
38、atesoil porosity, moisture, nutrients, and microorganisms with theappropriate biodegradation abilities. Additives may be pro-vided at or near the surface to percolate through the treatmentzone.5.3.2 Biosparging is similar to bioventing except that air isinjected directly into the ground below the wa
39、ter table in thesaturated zones, and contaminant volatility (and subsequenttreatment) is encouraged. Although the purpose is to deliveroxygen required by the microbes, vacuum pumps are oftenused to recover vapors for treatment prior to discharge.Nutrients and microbes may be added in the injection w
40、ell tostimulate and augment biodegradation.5.4 Solid-phase bioremediation treats soils above ground,primarily in contained treatment cells or tanks. Techniquessimilar to landfarming are used, including irrigation, tilling,and nutrient and microbe additions. As with in situbioremediation, treatment c
41、an involve biostimulation or bio-augmentation. Losses through volatilization and leaching canbe minimized through treatment design and implementation.The contaminated soil is contained, and is defined with respectto the volume and concentration of the oil, especially as the soilis homogenized during
42、 processing.5.4.1 A comprehensive contaminated materials handlingplan (CMHP) should be developed prior to excavation andtreatment. It may include the designation of a materials stagingarea present within the treatment facility and equipmentdecontamination within delineated exclusion zones.5.4.2 A co
43、mprehensive health and safety program should bein effect throughout the remediation project. This program mayinclude medical examinations of employees, contact and respi-ratory protection, and air, soil, and water monitoring.5.4.3 The treatment facility should contain appropriate pro-tection from ra
44、infall and flooding, and facilities to handleexcess water at the site. After the appropriate soil moisturecontent is determined for the specific treatment, a moisturebudget should be calculated. This should maintain the propermoisture content balance between moisture added by irrigationand rainfall,
45、 and moisture lost through evaporation,transpiration, and percolation.5.4.4 Solid heaping involves piling the contaminated soil toseveral meters, usually over a network of perforated piping thatmay be layered throughout. Nutrients, water, and microorgan-isms are added, and air is drawn through the p
46、ipes by vacuum.The vacuum system exhaust may be treated prior to discharge,effectively removing airborne volatile or semi-volatile compo-nents.Advantages include a requirement for less space and lessmaterial handling compared with solid-phase treatment(landfarming), and diminished volatile losses. L
47、eachates arecollected and treated, recirculated or discharged.5.4.5 Composting promotes biodegradation in stored wastesby adding bulking agents (biodegradable or non-biodegradable) that enhance soil permeability. The biologicdecaying process is often thermophilic, thus limiting the typesof microbes
48、and associated degradation rates. Three basicsystems have been used. “Open windrow” stacks the waste inlong piles that are aerated through constant excavation andreconstruction.“ Static windrow” is similar to heap methods,laying the soil over a network of perforated pipes that aeratethrough forced a
49、ir. “In-vessel” methods enclose the soil in aclosed reactor that aerates and mixes the soil both physicallyand by means of forced air. The material remaining aftertreatment can serve as a source for fill, cover, and landscapingmaterial.5.5 Slurry-phase bioremediation combines contaminatedsolids (soil, sludge, sediment) and liquids to form a slurrysuspension. The slurry is supplemented with nutrients, air oroxygen-releasing chemicals, or microorganisms, or a combi-nation thereof, in a bioreactor system. The slurry is stirred oragitated to enhance contact between the oil, nutri
