Exploration and Production (E&P) Waste Management Guidelines

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THE E& P FORUM

EXPLORATION AND PRODUCTION (E&P)WA S TE MA NAGEMENT GUIDELINES

Repo rt No. 2.5 8/196

September 1993



E& P Forum

Exploration & Production (E& P)

W aste M anagem ent G uidelines

R eport N o. 2.58/196

Septem ber 1993

E& P Forum , 25–28 O ld B urlington Street, London W 1X 1LB

Telephone: 44-(0)71-437 6291 Fax: 44-(0)71-434 3721

Th ese gu ide line s have b ee n prep ared for the E & P Fo rum by the ir

Environm ental Q uality C om m ittee throug h their W aste M anagem ent

G uidelines Task Force.

M s C . K. O w ens Exxon, C hairperson

M r D . R . R ycroft Phillips

M r M . T. Stephenson Texaco

M r G . N orris A m erada H ess

M r J. A . Johnson C onocoM r L. W . C ram e A m oco

M r C . Inglesfield SIPM

M r A . G rieg Shell Expro

The O il Indu stry International Exploration and Prod uction Forum (E& P

Forum ) is the international association of oil com panies and petroleum

industry organisations form ed in 1974. It w as established to represent its

m em bers’interests at the International M aritim e O rganisation and other

specialist agen cies of the U nited N ation s, governm en tal and other

international bodies concerned w ith regulating the exploration and

production of oil and gas. W hile m aintaining this activity, the Forum now

conce rns itself w ith all asp ects o f E & P operations, w ith particular

em phasis on safety of personnel and protection of the environm ent, and

seeks to establish industry positions w ith regard to such m atters.

A t present the Forum has 48 m em bers m ade up of 33 oil com panies

and 15 national oil industry associations, operating in 52 different countries.

The w ork of the Forum covers:

m onitoring the activities of relevant global and regional international

organisations;

developing industry positions on issues;

advancing the positions on issues under consideration, draw ing on the

collective expertise of its m em bers; and

dissem inating inform ation on good practice through the developm ent

of industry guidelines, codes of practice, check lists etc.

W hilst every effort has been m ade to ensure the accuracy of the

inform ation contained in this publication, neither E& P Forum nor any of its

m em bers w ill assum e liability for any use m ade thereof.

D esign and layout: W ords and P ublications, O xford

A uthors

The E& P Forum

D isclaim er

A cknow ledgm ents



EXPLORATION AND PRODUCTION (E&P)WASTE MANAGEMENT GUIDELINES

INTRODUC TION 2

Scope 2

B ackground 2

R esources Included in this D ocum ent 2

PRINCIPLES OFWA S TE MA NA GEMENT 4

W aste M anagem ent H ierarchy 4

A rea-Specific W aste M anagem ent Plans 6

AN OVERVIEW OFTHE OIL EX PLORA TIONA ND PRODUC TION PROC ES S 8

Seism ic Identification of Potential H ydrocarbon

R eserves 8

Exploratory D rilling 9

C onstruction 10D evelopm ent and Production 10

M aintenance 10

D ecom m issioning and R eclam ation 11

WA S TE MA NA GEMENT METHODS 12

W aste M anagem ent M ethods 12Source R eduction M ethods 12

R euse 13

R ecycling/R ecovery 13

Treatm ent 13

R esponsible D isposal 13

Surface D ischarge 14

Injection 14

B iotreatm ent M ethods 16Landfarm ing 16

Landspreading 17

C om posting 18 B iological Treatm ent in Tanks 18

B iological Treatm ent—Package U nits 19

Therm al Treatm ent M ethods 19Incineration 19

C em ent Kilns—Fuel B lending 20

O pen B urning 20

Therm al D esorption System s 20

Solidification, Stabilisation and Encapsulation 21

Landfill 21

B urial 21

Pit M anagem ent 22

Solvent Extraction 22

APPENDICES

1. R eferences 24

2. G lossary of O il Industry Term s 26

3. W aste M anagem ent P lanning W orksheet 30

4. Sum m ary of W astes G enerated by E& P A ctivities 32

5. Specific W aste Inform ation 35

6. W aste M anagem ent O ptions—Sum m ary Tables 42

CONTENTS



W A S TE M A N A G E M E N T G U ID E L IN E S

Scope

B ackground

R esources Included in this D ocum ent

IN TR O D U C TIO N

These guidelines have been prepared for those oil and gas exploration and

production (E& P) com panies w ho require inform ation on the rang e of

w aste m anagem ent options available for w astes generated by their activi-ties. Sections of the docum ent provide:

a general description of w aste m anagem ent principles

an identification and overview of E& P activities and associated

w astes, and

options for w aste reduction, recycling, treatm ent and responsible

disposal.

O perators should be able to use these guidelines to develop a w aste m an-

agem ent program m e appropriate to their activities and to the ecological

sensitivity of the operating location. H ow ever, not all m easures discussed

in these guidelines w ill necessarily be appropriate for im plem entation in all

geographic areas or under all conditions. E& P Forum guideline docum entson operations w ithin rain forest, m angrove and arctic environm ents pro-

vide additional inform ation and considerations for these specific areas.

Specific requirem ents and standards for petroleum operators should be

determ ined by agreem ent betw een the operating com pany and the

authorities of a host country.

Effective and responsible w aste handling and disposal are key elem ents

of an organisation’s environm ental m anagem ent system . Exploration and

Production (E& P) w aste as defined for this docum ent w ill be any m aterial,

solid, liquid or m ixture that is surplus to requirem ents. There is increasing

international concern that w astes be properly m anaged in order to m in-

im ise their po tential to cau se harm to health or the environ m ent.

M oreover, efficient m anagem ent of w astes can reduce operating costs

and potential liabilities. C haracteristics of concern include flam m ability,

reactivity, corrosivity, longevity in the environm ent and hum an, anim al, or

plant toxicity.

This docum ent is designed as an inform ation source. It is not intended to

replace an operator’s responsibility to ensure adequate and effective han-

dling and disposal of generated w astes as required w ithin a host country’s

regulatory requirem ents.

D isposal options in som e areas m ay be restricted by lack of established

w aste m anagem ent facilities and infrastructure. In these cases, the oiland gas operator m ay find it necessary to construct and m anage the nec-

essary facilities. A lthough this approach m ay be expensive in the short

term , it can often m inim ise long-term liabilities.

In addition to the discussions on w aste m anagem ent options included in

this docum ent, a num ber of appendices are provided to clarify or provide

exam ples of som e topics presented in the text. These appendices are as

follow s:

A ppendix 1 provides a list of references either used during preparation

of this docum ent or providing supplem entary inform ation on various

issues presented.

A ppendix 2 is a glossary of oil industry term s encountered in this

docum ent.

2



A ppendix 3 contains a form for creating an inventory of w astes

generated during E& P activities.

A ppendix 4 provides tabulation of com m on types of w astes generatedduring E & P activities, the m ain sources of these w astes, constituents

of these w astes that m ay adversely im pact the environm ent w hen

present, and identification of the operations w hich m ay generate a

specific w aste stream .

A ppendix 5 includes sum m ary sheets on a variety of com m on E & P

w astes. These sheets discuss the characteristics of the w aste stream s

and som e w aste m anagem ent options that m ay be appropriate.

A ppendix 6 provides a table of com m on types of w astes generated

during E& P activities and a sum m ary of possible w aste m anagem ent

options.

3

IN TRO D U CTIO N



PR IN C IPLES O F

W A STE M A N A G EM EN T

The principles of w aste m anagem ent include the incorporation of a hierar-chy of w aste m anagem ent practices in the developm ent of w aste m an-

agem ent plans. Specific w aste m anagem ent practices m ay be tailored to

w aste and site characteristics as w ell as to availability of reuse, recycle,

treatm ent and disposal facilities.

C reating an inventory to identify and track w aste stream s, and record the

costs associated w ith m anagem ent of those stream s, can help provide a

baseline for identification of opportunities to im prove practices. A n accu-

rate inventory of w aste m anagem ent practices recording the types of

w astes, m ethods of treatm ent or disposal, and location of final disposal

w ill not only be a valuable tool for w aste m inim isation program m es, but

also be a source of data in the event of any question of liability for contam -ination, and site rem ediation. A ppendix 3 contains a sam ple w aste inven-

tory sheet to aid in this process.

Proper m anagem ent of w astes begins w ith pollution prevention. Pollution

prevention refers to the elim ination, change or reduction of operating prac-

tices w hich result in discharges to land, air or w ater. This principle should

be incorporated into the design and m anagem ent of E& P facilities and the

planning of associated activities. If elim ination of a w aste is not possible,

then m inim ising the am ount of w aste generated should be investigated.

R esponsible w aste m anagem ent m ay be accom plished through hierarchi-

cal application of the practices of sou rce reduction, reuse, recycling,

recovery, treatm ent and responsible disposal. Elem ents of these practices

are show n below :

Source Reduction—the generation of less w aste through m ore

efficient practices such as:

•m aterial elim ination

•inventory control and m anagem ent

•m aterial substitution

•process m odification

•im proved housekeeping

Reuse—the use of m aterials or products that are reusable in their

original form such as

•chem ical containers

•oily w astes for road construction and stabilisation•burning w aste oil for energy

Recycling/Recovery—the conversion of w astes into usable m aterials

and/or extraction of energy or m aterials from w astes.

Exam ples include:

•recycling scrap m etal

•recycling drilling m uds

•using cleaned drill cuttings for road construction m aterial

•recovering oil from tank bottom s and produced w ater

Treatment—the destruction, detoxification and/or neutralisation of

residues through processes such as:

•biological m ethods—com posting, tank based degradation

•therm al m ethods—incineration, therm al desorption

•chem ical m ethods—neutralisation, stabilisation

•physical m ethods—filtration, centrifugation

4


W aste M anagem ent H ierarchy



Responsible Disposal—depositing w astes on land or in w ater using

m ethods appropriate for a given situation. D isposal m ethods include:

•landfilling

•burial

•surface discharge

•landspreading or landfarm ing•underground injection

The flow diagram show n in Figure 1 displays how these w aste m anage-

m ent practices m ay be applied. Specific m ethodologies w hich apply these

principles are presented in the section on W aste M anagem ent M ethods.

The role of tem porary and perm anent storage of w astes in the m anage-

m ent process is not addressed in Figure 1.

The potential ecological sensitivity of the location of operations is key to

the selection of an appropriate m anagem ent practice for a specific w aste.

This m ay require inform ation on geology, hydrology, clim ate and biological

com m unities. Environm ental Im pact A ssessm ent docum ents can be auseful resource.

5

P R IN C IP LE S O F W A S TE M A N A G E M E N T

FIGU RE 1: Key Waste Handling,Minim isation and Disposal Dec isions

INVENTORY

CHARACTERISE

SEGREGATE

IS THERE A RESIDUE?

DOES IT REQUIRE

TREATMENT(S)? TREATMENT(S)STOP

DISPOSAL

Minim isation Exam ple s

REDUCE

REUSE

RECYCLE/

RECOVER

Process modification or design change

Material elimination

Inventory control and management

Material substitution

Improved housekeeping

Chemical containers

Oily wastes for road spreading

Cleaned drill cuttings for roadbed

material or landfill cover

Recycle scrap metalRecycle paper

Recycle drilling muds

Burn waste lubricating oil for energy recovery

Recover oil from tank bottoms, produced

water and drilling muds

No

Yes

Yes

No



A n area-specific w aste m anagem ent plan directly relates the choice of

w aste handling and disposal options to the ecological sensitivities, regula-

tory requirem ents and available facilities/infrastructure of the geographical

area involved. The plan should be w ritten from the field perspective and

provide specific guidance for handling each w aste stream . In developing

such a plan, an E& P facility or com pany could follow the 10 general stepsoutlined below .

Step 1: Management Approval

M anagem ent approval and support should be obtained. Key personnel or

other resources and scheduling issues should be resolved such that m an-

agem ent is aw are of the tim ing and scope of the plan. The overall goal(s)

of the w aste m anagem ent plan should be established w ith m easurable

objectives stated for each goal.

Step 2: Area Definition

The w aste m anagem ent plan is area-specific and should include a descrip-

tion of the geographical area and specific business activities addressed.

The prim ary consideration in selecting an area is hom ogeneity from both

an ecological and a regulatory standpoint.

Step 3: Waste Identification

O perations personnel should identify all the w astes generated w ithin the

area d efined for each E & P activity (i.e., production, drilling,

com pletion/w orkover, natural gas plants). A brief description for each

w aste (sources, percent oil and/or saltw ater content and approxim ate vol-

um e) w ill assist in further m anagem ent steps. A ppendix 3 contains an

inventory form w hich m ay facilitate this effort.

Step 4: Regulatory Analysis

R eview international, regional and host country law s and regulations to

determ ine the types of w astes for w hich m anagem ent practices should

be highlighted. W aste types for w hich the regulations do not adequately

define m anagem ent requirem ents should then be identified.

Step 5: Waste Categorisation

The physical, chem ical and toxicological properties of each w aste should

be identified. This inform ation m ay be found via M aterial Safety D ataSheets (M SD S), m anufacturers inform ation, process know ledge, historic

inform ation or lab analyses. A system to categorise w aste stream s accord-

ing to their health and environm ental hazards can then be developed.

Step 6: Evaluation of Waste Management and Disposal Options

A list of the potential w aste m anagem ent option(s) for each w aste should

be com piled u sing the section o n W aste M anagem ent M ethods and

A ppendices 5 and 6 as a guide, and available options should be identified.

The acceptability of each option for the different ecological dom ains in the

plan area can then be determ ined.

Evaluation should include: environm ental considerations; location; engi-

neering lim itations; regulatory restrictions; operating feasibility; eco-

nom ics; potential long-term liability; etc. The list of the acceptable w aste

6


A rea-Specific W aste M anagem ent Plans



m anagem ent options and the desirability of each should be review ed by

appropriate operations personnel and m anagem ent.

In the event that intractable w aste stream s (such as those containing poly-

chlorinated biphenyls (PC B s) or radioactivity) are identified, the m anage-

m ent m ethod of perm anent storage in specialised storage facilities m aybe the only available option for reducing environm ental risk.

Step 7: Waste Minimisation

O pportunities for reduction or elim ination of w aste, volum e or toxicity

reduction, recycling and reclaim ing, or treatm en t should be review ed

w hen evaluating m anagem ent options. W hen a potential w aste m inim isa-

tion practice is identified, a pilot test m ay be desired for evaluation.

R evision of the w aste m anagem ent plan should be m ade to reflect any

m inim isation practices im plem ented.

Step 8: Selection of Preferred Waste Management Practice(s)

From the evaluation of w aste m anagem ent and disposal options, selec-

tion of the best practice for that operation and location can be m ade. A

life-cycle analysis assessing the risks associated w ith storage, treatm ent,

transport and disposal of a particular w aste stream m ay provide additional

insight into w hich m anagem ent practices should be given preferred sta-

tus. Through these processes, operations personnel m ay justify several

of the current w aste m anagem ent practices and/or identify new or m odi-

fied practices.

Step 9: Implementation of an Area Waste Management Plan

C om pile all the preferred w aste m anagem ent and disposal options for

each w aste found in a given operating area into one com prehensive, area-

specific w aste m anagem ent plan.

The recom m ended w aste m anagem ent practices should be sum m arised

in concise docum ents for use at the field level. D escriptions sh ould

include only the w astes generated by the operations in the specific area or

w ithin an operator’s responsibility. Each w aste description should indicate

the chosen w aste m anagem ent and disposal practice.

Step 10: Plan Review and Update

Effective w aste m anagem ent is an ongoing process. The plan should bereview ed w hen ever new w aste m anagem ent practices or options are

identified. A procedure to review and update the w aste m anagem ent plan

should be established, and practices m odified to reflect changing tech-

nologies, needs, or regulations.

A rea w aste m anagem ent planning, im plem entation and review offers

reassurance w ith regard to :

protection of the environm ent and ongoing com pliance w ith regulatory

requirem ents

ongoing training of field personnel

appropriateness of the plan itself, and

m inim isation of the volum e and toxicity of the w astes

The w aste m anagem ent plan should be a living ‘evergreen’docum ent

w hich requires periodic review and revision.

7

P R IN C IP LE S O F W A S TE M A N A G E M E N T



AN O VERVIEW O F TH E O IL AN D

G AS EXPLO RATIO N AN D

PRO D U CTIO N PRO CESS

In order to appreciate the potential im pacts of oil and gas developm ent

upon the environm ent, one m ust understand the activities involved. This

chapter briefly describes the oil and gas exploration and production pro-

cess. The guidance in this docum ent addresses only the w aste m anage-

m ent aspects of these activities. In order to fully understand the range of

environm ental im pacts associated w ith these activities, reference should

be m ade to other guidelines and docum ents listed in A ppendix 1.

In the follow ing discussions, com m on w astes are listed for each activity.

A m ore detailed listing of w astes associated w ith various E & P activities is

provided in A ppendix 4.

In the first stage of the search for hydrocarbon-bearing rock form ations,

geological m aps are review ed to identify m ajor sedim entary basins. A erial

photography m ay be used to identify prom ising landscape form ations such

as faults or anticlines. M ore detailed inform ation is then assem bled using a

field geological assessm ent, follow ed by one or m ore of three m ain survey

m ethods: m agnetic, gravim etric and seism ic. O f these a seism ic survey is

the m ost com m on and is often the first field activity undertaken.

Description

Seism ic surveys require the generation of acoustic w aves at specified

points along a relatively straight survey line. The acoustic w aves are

reflected by changes in the subsurface geological strata. The reflections

are detected by m any sensors arranged along several kilom etres of the

survey line (over several square kilom etres in the case of a 3D survey) and

recorded. Line preparation m ay involve cutting vegetation prior to survey-

ing the data point and sensor locations. A s recording progresses along the

survey line onshore, the sensors are m oved to new positions along the

survey line by crew s using vehicles or helicopters. The data are processed

by com puter to m ap the underlying strata and help define the size and

shape of any geologic structure w orthy of further investigation.

Several m ethods are available to gene rate the acoustic w aves; these

include the use of shot holes, Vibroseis techniques, or air or w ater guns.The shot hole m ethod involves the detonation of sm all explosive charges

placed in sm all diam eter holes drilled to a depth generally ranging from

one to thirty m etres. In the Vibroseis m ethod, a group of three to five

heavy vehicles (vibrators) low er and then vibrate a heavy pad at specific

points on the surface. A ir or w ater guns create the acoustic w aves used

for the survey by releasing com pressed air or w ater to create loud sonic

vibrations.

B ecause land seism ic activities are highly m obile, base cam ps are tem po-

rary in nature. In order to protect surface w ater bodies, sanitary pits and

biodegradable garbage pits should be at least 100 m etres from the w ater,

if possible. N on-biodegradable, flam m able w astes m ay be burned and the

ashes buried w ith the non-flam m able w astes. This burial should be at

least one m etre deep. If the area w ater table is high, burial criteria should

be reconsidered.

8


Seism ic Identification of PotentialH ydrocarbon Reserves



Com m on W astes

The prim ary w astes from seism ic operations include dom estic w aste,

sew age, explosive w astes, lines, cables and vehicle (including ship) m ain-

tenance w astes.

O nce a prom ising geological structure has been identified, the only w ay to

confirm the presence of hydrocarbons and the thickness and internal pres-

sure of a reservoir is to drill exploratory boreholes (‘w ells’).

The location of a drill site is dependent upon the characteristics of the

underlying geological form ations. M odern drilling techniques allow som e

flexibility in choice of location, allow ing consideration of both environm en-

tal protection and logistical needs, w hile still reaching reservoir develop-

m ent objectives.

Description

A site is constructed to accom m odate drilling operations and support ser-vices. O ffshore, a drilling barge, sem i-subm ersible drilling rig or a drilling

ship is used to provide all of the functions associated w ith drilling the w ell.

O n land, a typical one-hole exploration site occupies betw een 5000 and

20,000 square m etres. The type of site construction is dependent on sea-

sonal constraints and geography. D rilling rigs and support equipm ent are

norm ally divided into m odules to facilitate transportation. D epending on

access roads, site location and m odule size and w eight, drilling rigs m ay

be m oved by land, air or w ater transportation.

O nce on site, the rig and a self-contained support cam p are assem bled.

Typical m odules include a derrick, drilling m ud handling equipm ent, pow er

generators and cem enting equipm ent. The cam p provides w orkforce

accom m odation, canteen facilities, com m unications, vehicle m aintenance

and parking areas, a helipad (for rem ote sites), fuel handling and storage

areas, and provision for collection, treatm ent and disposal of w astes.

O nce drilling com m ences, drilling fluid or m ud is continuously circulated

dow n the drill pipe and back to the surface equipm ent to balance under-

ground hydrostatic pressure, cool and lubricate the bit and flush out rock

cuttings. The risk of uncontrolled flow from the reservoir to the surface is

further reduced by using blow out preventers, a series of hydraulically actu-

ated steel ram s that can close around the drill string or casing to quickly

seal off a w ell. Steel casing is run into com pleted sections of the borehole

and cem ented into place. The casing and cem ent provide structural sup-

port to m aintain the integrity of the borehole, isolate underground form a-tions, and protect usable underground sources of w ater. W here a hydro-

carbon form ation is found, initial w ell tests are conducted to establish flow

rates, form ation pressure, and the physical and chem ical characteristics of

the oil and gas.

Com m on W astes

The prim ary w astes from exploratory drilling operations include drilling

m uds and cuttings; cem enting w astes; w ell com pletion, w orkover and

stim ulation fluids; and production testing w astes. O ther w astes include

excess drilling chem icals and containers, construction m aterials (pallets,

w ood, etc.), process w ater, fuel storage containers, pow er unit and trans-

port m aintenance w astes, scrap m etal and dom estic and sew age w astes.

9

AN O VERVIEW O F THE O IL AND GA S EXPLO RATIO N A ND PRO DU CTIO N PRO CESS

Exploratory D rilling



C onstruction of som e infrastructure and facilities w ill be required to sup-

port activities.

Description

C onstruction of facilities such as roads, cam ps, canals and pipelines m ay

be required both before and during the developm ent and production pro-cess. Th e construction process m ay use a w ide variety of m aterials,

equipm ent and m ethods. The facilities required for a specific activity w ill

depend on the activity and its geographic location.

Com m on W astes

The prim ary w astes from construction activities include excess construc-

tion m aterials, used lubricating oils, paints, solvents, sew age and dom es-

tic w astes.

D evelopm ent and production operations are conducted to extract the oil

and gas from the reservoir.

Description

A sm all reservoir m ay be developed using one or m ore of the exploratory

w ells. Further developm ent of the reservoir m ay require additional w ells.

A production facility m ay be required to separate, store and transport pro-

duced fluids. The size and type of the installations needed for storing, sep-

arating and transporting oil, gas and w ater w ill depend on the nature and

location of the reservoir, the volum e and nature of produced fluids and the

export option selected. These options include transport by road, w ater-

w ay, pipeline or som e com bination of these.

R outine operations on a producing w ell include m onitoring, safety and

security inspections and periodic dow nhole servicing using a w ire line unit

or a w orkover rig. In som e areas, a self-contained base cam p m ay be

established to support routine operations. The base cam p provides w ork-

force accom m odation, com m unications, vehicle m aintenance and parking,

fuel handling and storage, and provision for collection, treatm ent and dis-

posal of w astes.

The operator w ill be able to extract only a portion of the oil present using

natural pressure an d sim ple p um ping. A range o f enhanced recovery

m etho ds, including w aterflood, gas injection and m etho ds em ploying

chem icals, gases or heat m ay be used to increase the efficiency of oil pro-

duction.

Com m on W astes

In addition to the w astes listed under Exploratory D rilling, C onstruction

and M aintenance, the m ain w astes from developm ent and production

operations include discharged produced w ater, flare and vent gas, produc-

tion chem icals, w orkover w astes (e.g. brines) and tank or pit bottom s.

M aintenance of vehicles, m echanical equipm ent and infrastructure m ay

be required for operations of extended duration.

Description

M aintenance activities are com m on to all phases of the exploration and

production process. D uring seism ic and construction activities, m ainte-

nance is essentially lim ited to vehicle repair and inspection. Exploratory

drilling m aintenance activities include vehicle and drilling rig repair and

10


C onstruction

D evelopm ent and P roduction

M aintenance



inspection. M aintenance activities during developm ent and production

include repair and inspection of vehicles, generators, drilling rigs, w orkover

rigs, fluid process equipm ent and infrastructure.

Com m on W astes

The prim ary w astes associated w ith m aintenance activities include batteries, used lubricants, filters, hoses, tyres, paints, solvents, contam inated

soil, coolant and antifreeze chem icals, used parts and scrap m etals.

O il and gas installations are decom m issioned at the end of their com m er-

cial life.

Description

D ecom m issioning generally involves perm anently plugging and abandon-

ing all w ells, and m ay include rem oval of buildings and equipm ent, transfer

of buildings and roads to local com m unities or host governm ent entities,

im plem entation of m easures to encourage site re-vege tation and sitem onitoring.

Com m on W astes

The prim ary w astes from decom m issioning and reclam ation include con-

struction m aterials, insulating m aterials, plant equipm ent, sludges and con-

tam inated soil.

11

D ecom m issioning and R eclam ation

AN O VERVIEW O F THE O IL AND GA S EXPLO RATIO N A ND PRO DU CTIO N PRO CESS



W A STE M A N A G EM EN T M ETH O D S

A s in any aspect of environm ental m anagem ent, there are som e general 4

good practices that should be em ployed. These good practices not only

protect health and the environm ent but also help protect E& P operatorsfrom potential long-term liabilities associated w ith w aste disposal. W aste

m anagem ent m ethods should be selected based upon the hierarchy pre-

sented on page 4.

Som e of the treatm ent and disposal m ethods that m ay be used for E& P

w astes are described on page 14 onw ards. The om ission of a particular

m anagem ent option from the list discussed here is not m eant to im ply

that it can not be effective. C ertainly, as research on w aste m anagem ent

progresses, additional options w ill be identified.

A n im portant aspect of a w aste m anagem ent program m e is the need to

segregate w aste m aterials according to their general physical and chem i-cal characteristics. A part from safety concerns, an initial w aste characteri-

sation w ill help determ ine w hich w aste stream s are sim ilar and m ay be

com bined to sim plify storage, treatm ent, recycling, and/or disposal, and

w hich stream s should rem ain segregated. Failure to recognise the need

for w aste segregation m ay result in the creation of a w aste m ixture

incom patible w ith the desired recycling or disposal option and result in the

need for extensive lab analysis and higher w aste disposal costs.

Source Reduction Methods

Source reduction m eans elim inating or decreasing, to the extent practical,

the volum e or relative toxicity of w astes generated by using alternate

m aterials, processes or procedures.

Volum e —O pportunities to achieve significant w aste volum e reductions for

som e E& P w astes are lim ited because their volum es are prim arily a func-

tion of activity level and age or state of reservoir depletion. For exam ple,

the proportion of discharged produced w ater typically increases as the

reservoir is depleted. A lso, the volum e of drilling m uds generated is gen-

erally a fun ction of the num ber of w ells d rilled an d their depth.

N evertheless, opportunities exist for source reduction and efforts should

be m ade to exploit them . For exam ple, use of proper solids control equip-

m ent can reduce the volum e of m ud discharged.

Process m odification m ay be possible through m ore effective use of

m echanical com ponents, such as m ore effective drill bits, rather thanchem ical additions. G ravel packs and screens m ay significantly reduce the

volum e of form ation solids/sludge produced. Im proved controls w ill help

m inim ise m ud changes, engine oil changes and solvent usage.

Toxicity —Substitution of products that result in the generation of less

toxic w astes should be investigated. For exam ple, biocides, corrosion

inhibitors, coagulants, cleaners, solvents, dispersants, em ulsion breakers,

scale inhibitors, viscosifiers and w eighting agents should be selected w ith

potential environm ental im pacts and disposal needs in m ind. Som e exam -

ples are the selection of m ud and additives that do not contain significant

levels of biologically available heavy m etals or toxic com pounds, and the

use of m ineral oils in place of diesel oil for stuck drill pipe.

O ther efforts should include: efficient planning so that all com m ercial

chem ical products are used on the site or returned unused to vendors;

12


W aste M anagem ent M ethods



consideration of bulk chem ical purchases to elim inate drum s; and use of

drains and sum ps to collect and segregate spills.

Reuse

A fter all w aste reduction options have been considered, the next step is to

evaluate reuse of the w aste m aterial. The reuse m ay be in the sam e, alter-native, or dow ngraded service, or the return of unused m aterials for re-

issue or reuse in other industries. Exam ples include: use of drill cutting

w aste for brick m anufacture and roadbed m aterial, use of vent gas for fuel,

use of produced w ater or process w ater as w ash w ater, and return of oil

based drilling m ud to the vendor for reprocessing and re-issue.

W astes such as tank bottom s, em ulsions, heavy hydrocarbons, and hydro-

carbon bearing soil m ay be used for road oil, road m ix, or asphalt. These

w astes should be analysed to ensure they are not flam m able and have a

m ixed den sity and m etals content consisten t w ith road oils or m ixes.

A pplication of hydrocarbon w astes to roads should be at loading rates that

m inim ise the possibility of surface run-off.

Recycling/Recovery

A fter all w aste reduction and reuse options have been considered, the

next step is to evaluate recycling and recovery of the w aste m aterial either

in-process, on-site, or w ith outside contractors. W hen available, the recy-

cling of drilling m uds in m ud plants should be considered.

There are potential benefits in the sale of recovered hydrocarbons. A ll

hydrocarbon w astes should be returned to the production stream w here

possible. R ecove ry of hyd rocarbo ns from tank bottom s and sep arator

sludges via centrifuging or filtering can be accom plished at on-site produc-

tion facilities or off-site com m ercial facilities.

W hen recycling scrap m etal, m onitoring should be considered to ensure

that m etal w ith N O R M (LSA ) scale is not sent to the recycling facility along

w ith uncontam inated m aterials.

Treatment

A fter source reduction, reuse, recycling and recovery opportunities have

been exam ined, potential treatm ent steps to m inim ise w aste volum es or

toxicity should be considered.

Treatm ent m ethods include: biological m ethods (e.g. landspreading, com -

posting, tank based reactors), therm al m ethods (e.g. therm al desorption

and detoxification), chem ical m ethods (e.g. precipitation, extraction, neu-tralisation) and physical m ethods (e.g. gravity separation, filtration, centrifu-

gation).

Exam ples of treatm ent m ethods include: biodegradation of oily w astes in

a pit by tillage and addition of nutrients (fertilizer); and stabilisation of m ud

pit w astes by adjusting the pH to chem ically stabilise and reduce potential

toxicity and m obility of inorganic com pounds.

Responsible Disposal

Finally, after all practical source reduction, reuse, recycling, recovery and

treatm ent options have been considered and incorporated, responsible dis-

posal options for the residue should be determ ined. The follow ing criteria

should be exam ined w hen evaluating w aste disposal options. This inform a-

tion w ill help in determ ining the long-term fate of a w aste and its con-

stituents and should be applied to both on-site and off-site disposal facilities.

13




G eneral A rea O verview —Review the relevant law s and regulations of the

area and the availability of off-site disposal facilities.

G eneral Site O vervie w —Review the area-w ide topographical and geologi-

cal features. A lso, review current and likely future activities around the dis-

posal site.

H ydrological Evaluation —R eview hydrogeologic data to identify the loca-

tion, size and direction of flow for existing surface w ater bodies and

aquifers characterised as fresh or usable.

A rea R ainfall or N et Precipitation C ondition s—O btain historical rainfall dis-

tribution data to establish m oisture requirem ents for landspreading, deter-

m ine how quickly reserve pits w ill dry, predict net evaporation rates, eval-

uate pit overflow potential, etc.

Soil C onditions and Loading C onsiderations —D eterm ine soil conditions

prior to m aking decisions on loading for landspreading and w hether or notpits w ill require liners. For exam ple, in high clay content and perm afrost

areas, liners m ay not be necessary for reserve pits. In other areas w ith

sandy soils and shallow usable groundw ater, liners or even tanks m ay be

m ore appropriate.

D rainage A reas —D eterm ine natural or existing drainage patterns and iden-

tify drainage devices needed to control w ater flow into, onto, or from facil-

ity system s.

Environm ental Sensitivity —C onduct a site evaluation to identify environ-

m entally-sensitive features such as w etlands, urban areas, historical or

archaeological sites, protected habitats, or presence of endangered species.

A ir Q uality —G ive consideration to potential air quality im pact of w aste

m anagem ent facilities.

Surface discharge is one dispo sal option for aqueous w aste stream s.

Factors to consider include the sensitivity and capacity of the potential

receiving environm ent, the concentration of potentially harm ful com po-

nents in the w aste and the volum e of the discharge stream . The capacity

of the receiving environm ent to naturally absorb pollutants is a function of

the dilution potential and volum e of the receiving w ater body. In this

regard, the discharge of a high volum e, saline w aste stream into a sm all

creek m ay not be appropriate w hile discharge of the sam e w aste streaminto a large w ater body m ay be acceptable.

Injection refers to the pum ping of w aste fluids or slurries dow n a w ell into

suitable underground form ations for disposal. Injection m ay refer to the

one tim e pum ping of w astes dow n an annulus or to specially m onitored

w ells w hich m ay receive fluids for m any ye ars. D isposal w ells are

designed to provide an avenue, or w ellbore, to transport liquids into under-

ground reservoirs in a m anner that w ill not adversely affect the environ-

m ent. The target form ation for disposal should be g eologically and

m echanically isolated from usable sources of w ater. This form ation w ill

not contain com m ercial quantities of oil and gas.

M any liquid w astes m ay be m anaged using an injection w ell. The highest

volum e fluid that m ay be handled by E& P disposal injection w ells is pro-

14


Surface D ischarge

Injection



duced w ater. O ther w astes suitable for injection m ay include: process

w ater, blow dow n liqu ids, cooling w ater, dehydration and sw eeten ing

w aste liquids and w aste drilling fluids.

A s a m anagem ent practice, injection (other than annular injection) is an

expen sive process requ iring exten sive planning and control. In m ostcases, an injection w ell and system w ill require considerable E& P activity

in a particular area to justify the investm ent in drilling a w ell or converting

an existing producing w ellbore to injection service. O ther considerations

include:

The injection volum e required—the volum es of produced w ater and

other liquid or solid w astes to be injected should be determ ined. This

w ill indicate the num ber of w ells to be drilled and connected to the

injection system .

The nature of the form ation—the form ation to receive the w aste

should have sufficient perm eability, porosity, thickness and areal

extent, and low reservoir pressure in order to handle the forecast

volum e and injection rate on a long-term basis. The geology of som eareas m ay be unsuitable for injection due to the presence of extensive

geological faults resulting in reservoirs sm all in areal extent, form ations

that seal poorly around a w ell, form ations that tend to fracture to the

surface, or form ations w ith insufficient perm eability or close proxim ity

to aquifers.

The m echanism for transportation of the w aste to the injection w ell—a

gathering system and pum ping facilities m ay be necessary or the

transport could be via tank truck or other m eans.

Pre-treatm ent(s) necessary before injection—treatm ents necessary

before injecting produced w ater into a salt w ater disposal w ell m ay

include oil rem oval, coagulation and sedim entation to rem ove

suspended solids, filtration, aeration, oxygen exclusion and rem oval,

and bacteria and m ineral scale treatm ent. Solid w astes m ay have to be

ground and slurried prior to annular injection.

Annular Injection

A nnular injection is a disposal m ethod w here pum pable w astes (usually

reserve pit fluids) are injected into the surface casing or production casing

annulus (or other casing or casing annulus). This practice should be m an-

aged so that the w astes do not enter underground sources of w ater.

A nnular injection is usually a ‘one-tim e’option and is not suitable for con-

tinuous disposal. The reasons for this include the m echanical inability to

clean the disposal zone of accum ulated debris and the threat of corrosion

of the production casing string and the interior of the surface pipe or othercasing. If the surface pipe is breached by corrosion during long term injec-

tion service, the injected fluids m ay enter usable w ater sources.

Downhole Injection

D ow nhole disposal of w aste m uds and cuttings, both oil and w ater based,

from both onshore and offshore w ells m ay be suitable. The principle and

practice is the sam e as for annular injection, described above, except that

the liquid or slurried m ud w aste is pum ped dow nhole. D ue to the large

particle sizes, drill cuttings cannot be injected dow nhole directly as they

w ill quickly plug the receiving form ation. The cuttings m ust be broken up

into sm all particles and slurried w ith m ud or w ater before they can be

injected. System s typically include a ‘grinding’m achine, pum ps, recirculat-

ing lines, tanks and shakers or desanders to rem ove large solids.

15




M any organic com pounds present in E& P w astes m ay be biodegraded to

carbon dioxide and w ater using natural biological processes. H ow ever,

natural biodegradation of contam inants tends to be rate lim ited due to lim -

itations on the biological processes. These lim itations m ay be overcom e

by optim ising the biological conditions. The m ost im portant factors for

control of biological degradation of hydrocarbons are: an adequate supply of hydrocarbon degrading bacteria

availability of sufficient oxygen (and m ixing) for cell m etabolism

availability and balance of nutrients and m icro-nutrients necessary for

optim um bacterial m etabolism

m oisture control

tem perature and pH

salinity

The concentration and type of com pounds to be degraded m ay have a sig-

nificant im pact on the biodegradation process. Som e com pounds m ay be

readily degraded at low concentrations but inhibit degradation at higher

concentrations (for exam ple, som e hydrocarbon com pounds m ay be toxicto degrading organism s at high concentrations). O ther com pounds m ay be

degraded very slow ly by biological processes, require an acclim atisation

period or require co-m etabolites for degradation. In general, the com posi-

tion of an organic w aste should be exam ined to determ ine the feasibility

of reaching desired treatm ent levels. H igh levels of asphaltenes and/or

polynuclear arom atic hydrocarbons (PA H ) in a w aste m ay m ake biological

treatm ent an unlikely option for rapid rem oval of the hydrocarbon fraction.

C onversely, high concentrations of alkanes in a w aste w ould m ake it a

good candidate for biological treatm ent. In general, the biodegradability of

petroleum hydrocarbon fractions follow s the relationship: saturates > aro-

m atics > polars > asphaltenes.

H ydrocarbo n de grading m icrobes are ubiquitous in the en vironm en t.

H ow ever, they m ay be present in very low concentrations in som e w aste

stream s, environm ents exposed to extrem e conditions, or m aterials con-

tam inated by extrem ely high con cen tration s of certain com poun ds. If

m icrobial populations are low in a w aste, native soils m ay often provide the

m icrobial inocula necessary for biodegradation (as described in the land-

farm ing, landspreading and com posting sections below ). If for som e reason

soil m icrobes are inadequate or the w aste conditions are particularly harsh,

strains of bacteria adapted to m etabolise hydrocarbons under the desired

conditions m ay be added. W aste biological sludges from refinery w aste

w ater treatm ent system s, if available, are an excellent source of hydrocar-

bon degrading bacteria.

O f the biological treatm ents described below , landfarm ing and landspread-

ing m ay be considered disposal options as w ell as treatm ent. C om posting

processes and bioreactors generally convert the w aste into a less harm ful

product for subsequent use or disposal. R ates of biodegradation are high-

est for bioreactors and com posting, and low est for the less favourable bio-

logical conditions generally found in landfarm ing and landspreading.

Landfarming

Landfarm ing system s have been used for the treatm ent of oily petroleum

industry w astes for m any years. The landfarm ing process involves the

controlled and repeated application of w aste on a soil surface in order to

biodegrade hydrocarbon constituents by using m icroorganism s naturally

present in the soil. The landfarm ing area is periodically tilled to provide the

necessary m ixing and oxygen transfer. A ctive landfarm ing m ay include

addition of w ater, nutrients and other m aterials to enhance the biodegra-

16


B iotreatm ent M ethods



dation process in the w aste/soil m ixture, and to prevent the developm ent

of conditions that m ight prom ote leaching and m obilisation of inorganic

contam inants. The conditions under w hich degradation takes place are

typically aerobic. Volatilisation and dilution are tw o other im portant m echa-

nism s for reduction of degradation products in land applications of w aste.

Landfarm ing should not be confused w ith landfilling or burial, in w hich thew aste is deposited in m an-m ade or natural excavations for an indefinite

period of tim e. The conditions under w hich landfilled and buried w astes

are stored are usually anaerobic, w hich typically results in m uch slow er

degradation.

C are should be taken to avoid landfarm ing of m aterial w hich contains sig-

nificant levels of biologically available heavy m etals, persistent toxic com -

pounds, or low specific activity (LSA ) scale. A t inappropriate loadings,

these m ay accum ulate in the soil to a level that renders the land unfit for

further use. A site m onitoring program m e is recom m ended to ensure such

accum ulation is not occurring.

C onsiderations for the application of landfarm ing should also include the

site topography and hydrology, and the physical and chem ical com position

of the w aste and resultant w aste/soil m ixture. W aste application rates

should be controlled to m inim ise the possibility of run-off. W hen a facility

is properly designed, operated, and m onitored, landfarm ing is usually a rel-

atively cost-effective and sim ple technique. Landfarm s m ay require gov-

ernm en t perm its or approval and, de pe nd ing on soil cond itions, m ay

require a liner and/or groundw ater m onitoring w ells. M oisture control to

m inim ise dust (particulates) m ay also be necessary during extended dry

conditions.

Landspreading

The treatm ent processes involved in landspreading are sim ilar to those in

landfarm ing. H ow ever, landspreading refers to the one-tim e application of

liquid or solid w aste to a site. Landspreading m ay be an appropriate tech-

nique to reduce the organic content of a w aste. A s in landfarm ing, inorgan-

ic com pounds and m etals are not only diluted into the soil, but m ay be

incorporated into the m atrix through chelation, exchange reactions, cova-

lent bonding etc., or m ay becom e less soluble through oxidation, precipita-

tion and pH effects.

In landspreading as in landfarm ing, aerobic biodegradation of hydrocarbons

m ay be enhanced by nutrient addition to the w aste/soil m ixture and by

periodic tillage of the m ixture (to increase aeration). For E& P w astes, salts

and hydrocarbons are m ost frequently the com ponents w hich lim it theapplication rate of a w aste on a site. H ydrocarbon concentrations m ay be

m on itored after land spread ing to m easure prog ress and de term ine

w hether biodegradation processes should be enhanced.

In general, there is little regulatory guidance concerning landspreading

practices. This is prim arily due to the fact that landspreading sites only

receive a single application of w aste. This practice reduces the potential

for the accum ulation of w aste com ponents in the soil, as m ight be the

case in landfarm ing sites that receive m ultiple applications o f w astes.

C onstruction of a containm ent system (liners) or m onitoring of leachates

from the site is seldom required for landspreading sites. H ow ever, site

topography and hydrology, and the physical and chem ical com position of

the w aste and resultant w aste/soil m ixture, should still be assessed and

w aste application rates controlled to m inim ise the possibility of run-off.

17




Landspreading is m ost effectively used as a disposal m ethod for drilling

fluids and cuttings w ith low levels of hydrocarbons and salts, but it m ay

also be useful for other E& P w astes w ith these sam e ch aracteristics.

C haracterisation of a w aste, and treatability studies can be used to deter-

m ine w hether landspreading m ay be effectively im plem ented.

Composting

C om posting is a solid phase biological treatm ent technique sim ilar to land

treatm ent. B iodegradation rates are enhanced by im proving porosity, aera-

tion, m oisture content, and operating tem perature. It m ay be possible for

com post m ixtures w ith up to ten percent hydrocarbon to be reduced to

less than one percent in four to eight w eeks.

C haracteristics of com posting are:

W aste is m ixed w ith bulking agents (e.g. w ood chips, straw , rice hulls

or husks) to provide increased porosity and aeration potential. C are

should be taken to ensure the bulking agent provides sufficient

porosity to allow aeration even at high m oisture levels. M anure or agricultural w astes m ay be added to increase the w ater

holding capacity of the w aste/m edia m ixture and to provide trace

nutrients.

N itrogen and phosphorous based fertilisers, as w ell as trace m inerals

(e.g. Fe, C u, M o, M n, Zn, B , C o, N i) m ay be added to enhance

m icrobial activity.

M ixtures of the w aste, soil (to provide indigenous bacteria) and other

additives, m ay be placed in piles sm all enough (less than 3 feet deep)

to be tilled for aeration, or placed in containers or on platform s

designed to allow forcing of air through the com posting m ixture.

C om posting in closed containers allow s for control of volatiles.

The com post m ixture is m aintained near 40–60 percent w ater by

w eight to provide optim al m oisture conditions for biodegradation.

Com post system s are characterised by elevated tem peratures (30–70 °C)

w ithin the com post m ixture. The elevated tem perature increases

m icrobial m etabolism , but should be closely m onitored to ensure

tem peratures do not exceed 70 °C (m ay cause cell death). Tem perature

m ay be controlled by tilling the soil pile or by forced aeration.

The degradation of organic com pounds using com posting techniques can

be m uch m ore efficient than landspreading or landfarm ing techniques. In

addition, treated w aste is contained w ithin the com posting facility and its

properties m ay be readily m on itored. C om posted w astes that m ee t

health-based criteria m ay be reused as soil conditioners, landfill cover,

clean fill, etc.

Biological Treatment in Tanks

The sam e aerobic biological reaction that occurs during landfarm ing or

com posting processes m ay be accom plished at an accelerated rate using

an open or closed vessel or im poundm ent. The process is typically operat-

ed as a batch or sem i-continuous process. N utrients are added to a slurry

of w ater and w aste, and oxygen (for aerobic degradation) is provided by

air sparging and/or intensive m echanical m ixing of the reactor contents.

The m echanical m ixing also provides a high degree of contact betw een

m icroorganism s and the w aste com ponent to be biodegraded. A source of

m icrobes capable of degrading the organic constituents of the w aste m ay

also be required to accelerate start-up of the system .

O perating conditions (tem perature, pH , oxygen transport and m ixing, and

nutrient concentrations) m ay be easily m onitored and controlled in tank

18




based bioreactor system s. This control m akes optim isation of biological

processes possible, he nce en suring the best rate of biod eg radation.

B ioreactors generally require less space than land-based biological treat-

m ent processes. A disadvantage of bioreactors is that the m aintenance

and capital investm ent required is high relative to other form s of biological

treatm ent.

A fter reaching the desired level of treatm ent, the disposal m ethod for

residual reactor contents w ill be dictated by the concentrations of the

rem aining com ponents. D epending on the constituents, liquids m ay be

transported to w aste w ater treatm ent facilities, injected or discharged.

A fter dew atering, solids m ay be buried, applied to soils, used as fill, or fur-

ther treated to stabilise com ponents such as m etals.

Biological Treatment—Package Units

A nother variation of the optim ised aerobic biological w aste treatm ent sys-

tem is an activated sludge process com m ercially available in self-contained

package units for the treatm ent of sanitary w astes. The system typicallyincludes an aeration tank w ith an aerator system , a clarifier tank w ith

sludge recycle and a chlorination system for the final effluent. The process

is operated continuously w ith an influent loading rate set to the feeding

rate of the m icroorganism s to allow the biodegradation of the organic con-

stituents. Follow ing the m anufacturer’s recom m endations for operation is

suggested.

A lthough com m ercially available package units are highly efficient, they

m ust be protected from biological upsets. C are m ust be taken to prevent

the inadvertent dum ping of cleaning chem icals, solvents, used oils and

strong acids, caustics or detergents to the sanitary sew er collection system .

There are a variety of w aste treatm ent techniques based upon the applica-

tion of heat to w aste m aterials. The resulting products from these tech-

niques w ill depend on the am ount of heat em ployed. Low tem perature

treatm en ts m ay allow for recove ry of hydrocarbo ns and w ater from

w astes, w hereas the use of high tem perature technologies m ay destroy

organic com pounds via com bustion.

Incineration

Incineration uses com bustion to convert w astes into less bulky m aterials.

Incineration can refer to the practice of open burning of w astes in pits,

although the degree of com bustion achieved in com m ercial incinerators

w ill be difficult to achieve in open burning. This is because com m ercialincinerators can control the residence tim e, tem perature and turbulence

w ithin the incineration cham ber to optim ise com bustion. These incinera-

tors are often equipped w ith air pollution control devices to rem ove incom -

plete com bustion products, rem ove particulate em issions, and reduce S O x

and N O x em issions. There are m any types of incinerators, and m any air

pollution control m echanism s.

Incinerators are usually used to destroy organic w astes w hich pose high

levels of risk to health and the environm ent. A s a rule, incineration of m ost

E& P w astes is not necessary. H ow ever, if operations are located in a sen-

sitive environm ent and other disposal options are not available, then incin-

eration m ay be the best w ay to m anage oily w astes from E& P operations.

B ecause of its durability and ability to incinerate alm ost any w aste, regard-

less of particle size or com position, the type of incinerator best suited for

19

Therm al Treatm ent M ethods




m any E & P w astes is the rotary kiln. A rotating kiln tum bles the w aste to

provide extensive contact w ith hot burner gases. D epending on the size

and com plexity of an operation, sm aller incinerators can also be effective.

D isposal of solids rem aining after incineration should be m anaged proper-

ly. W hen organic com ponents of the w aste are incinerated, m etals con-centrations in the rem aining solids w ill increase. A n operator should

ensure that incinerator ashes resulting from the treatm ent of its w astes

are properly handled and disposed. Stabilisation m ay be required to pre-

vent release of harm ful leachates into the environm ent.

Cement Kilns—Fuels Blending

The use of a cem ent kiln, w hen available, is usually an attractive and less

expensive alternative to incineration of E& P oily w astes. O ily w aste m ay

go into a fuel blending program m e to replace fuel otherw ise needed to

fire the kiln.

The retention tim e and tem perature (typically 1,400 to 1,500 °C) w ithin acem ent kiln are ade qu ate to achieve therm al de struction of organics.

C em ent kilns m ay also have pollution control devices to m inim ise air em is-

sions from the process. The ash from w astes com busted in the kiln w ill

becom e incorporated into the cem ent m atrix. These ashes m ay provide a

desirable source of alum inium , silica, clay and other m inerals that are typi-

cally added in the cem ent raw m aterial feed stream .

Open Burning

O pen burning is typically used to dispose of cam p refuse, construction

m aterial, and hydrocarbon containing m aterials w ith properties or in areas

that m ake recycling, recovery, or transport unsuitable. W hen these condi-

tions exist and regulations perm it burning, burning should be conducted in

approved areas during daytim e hours and should not cause a nuisance.

The possible effects of em issions of particulates and products of incom -

plete com bustion should be considered, and com bustion m ethods that

m inim ise em issions should be em ployed, w hen available.

Thermal Desorption Systems

A therm al desorption system is a non-oxidising process using heat to des-

orb oil from oily w astes. M ost therm al system s burn fuel to provide heat to

volatilise the oil, but there are som e system s that use electric or electro-

m agnetic energy for heat. Therm al desorption system s are generally of tw o

types: low tem perature system s and high tem perature system s. The w ork-

ing tem perature of low -tem perature system s is usually 250 to 350 °C ,

w hile high tem perature system s m ay em ploy tem peratures up to 520 °C .Low tem perature system s m ay be sufficient to treat w astes w ith light oils.

H igh tem perature system s w ill be able to achieve low er final oil contents

for w astes containing heavier oils.

Therm al desorption of w aste stream s w ill prod uce various secondary

w aste stream s: solids, w ater condensate, oil condensate, and possibly an

air stream from the condenser. Each of these stream s m ay require analysis

to determ ine its characteristics so that the best recycle/disposal option can

be chosen. This is im portant if the original w aste had high salts or m etals

levels, or if there are no w astew ater treatm ent facilities on site, since addi-

tional treatm ent m ay be required to reduce the potential for environm ental

im pact from these stream s. In the case of air em issions, analysis m ay sug-

gest the need for air control m easures to capture certain constituents.

20




Solidification, stabilisation and encapsulation are often discussed together

as they m ay be jointly achieved by som e processes. In general, these pro-

cesses produce dry solids (either as a m onolith or a dry granular solid sim i-

lar to coarse soil). W astes treated by these technologies are stored and

not destroyed. H ow ever, the concentrations or m obilities of constituents

of concern in the treated w aste m ay be different from those in the originalw aste.

C em ent-based and pozzolanic (e.g. flyash) processes, as w ell as chem ical

stabilisation processes, have been applied in the oil industry to solidify

and/or stabilise w astes. These processes are especially effective for stabil-

isation of m etals in the w astes because, at the high pH of the cem ent m ix-

ture, m ost m etal com pounds are converted into non-biologically available

insoluble m etal hydroxides. H ow ever, high concentrations of organic com -

pounds, salts and bentonite have been show n to interfere w ith the curing

process, and therefore lim it the application of this treatm ent technique.

H ydrocarbons and salts do not interact w ith the cem ent m atrix and are

physically rather than chem ically bound w ithin the m atrix.

Lan dfills are generally sp ecially co nstructed an d m onitored facilities

designed to accom m odate burial of large volum es of w astes. H ow ever,

som e landfills m ay be little m ore than open dum ps. A landfill m ay be con-

structed in a m anner that m akes it an appropriate disposal site for certain

toxic w astes. A key consideration in the operation of a landfill site is the

need to ensure long-term containm ent. D esign considerations for a landfill

should, therefore, include:

A n im perm eable lining to contain the landfill contents. Liners m ay be

constructed of clay, plastic sheeting and/or m ulti-layer linings w ith

integrated drainage system s.

M onitoring boreholes or leachate collection system s to provide a

m eans for regular inspection of the effectiveness of the containm ent.

Special provisions for disposal of liquid w astes, or prohibition of liquids

disposal. If disposal of liquids is perm itted, the conditions should be

controlled to prevent leaching. The landfill design should include

arrangem ents for the collection and treatm ent of leachate.

The operator should keep in m ind that all landfills m ay not be constructed

to the sam e standards, and that industrial w astes should only be disposed

of in sites w ith the proper design criteria and proper m onitoring and m ain-

tenance program m es. Landfilled m aterials should not be capable of react-

ing to generate excess heat or noxious gases. Special system s m ay need

to be installed to collect generated m ethane. The operator should rem em -ber that landfilled w astes are not destroyed, but are actually in long-term

storage. D isposal sites should be operated either by the w aste generator

w ho w ill m aintain responsibility for its ow n w astes or by a properly m an-

aged disposal facility.

D ue to its sim plicity, burial of w astes in sm all pits at drilling and production

sites has been a popular m eans of w aste disposal in the past. H ow ever,

w ith current aw areness of pollutant m igration pathw ays, the risks associ-

ated w ith burial of w astes should be carefully considered. In general,

w astes w ith high oil, salt, or biologically available m etal content, industrial

che m icals, and othe r m aterials w ith harm ful com po ne nts that could

m igrate from the pit to contam inate usable w ater resources should not be

buried. B urial m ay be the best m ethod of disposal for inert unrecyclable

m aterials. If a pit’s contents contain concentrations of constituents only

21

Solidification, Stabilisation and E ncapsulation

Landfill

B urial




slightly elevated above levels regulated for disposal, then burial provides a

sim ple m echanism to reduce concentrations in the w aste, via dilution w ith

soil, as it is being disposed. This m ay often be the case for w ater based

m uds and cuttings. In dilution burial, the pit contents are m ixed w ith soils

from the pit and surrounding areas until the pit contents m eet specifica-

tions for burial, then the pit is covered and the surface graded.

B urial is a logical choice for w astes that have been stabilised, since m igra-

tion of the constituents of the w aste w ill be retarded by the stabilisation

process. H ow ever, if there is a reason for extra caution at a particular site

(either because of the constituents in the original w aste, or because of the

hydrogeologic characteristics of the site) then additional barriers to m igra-

tion such as barrier w alls around the pit, liners around the pit contents, or

a cap to prevent vertical m igration, could also be installed. A lternatively,

and if available, the w aste could be sent to a properly m anaged facility

designed to handle that type of w aste.

C onsideration of factors such as the depth to groundw ater, and the typeof soil surrounding the pit should be m ade before w astes are buried. This

ensures proper protection of soil and w ater resources.

W hen burial and/or pit closure is com plete, the area should be graded to

prevent w ater accum ulation , and revege tated w ith native species to

reduce potential for erosion and p rom ote full recovery of the area’s

ecosystem .

The use of pits, earthen or lined, is an integral part of E& P w aste m anage-

m ent operations. H istorically, on-site pits have been used for the m anage-

m ent of drilling solids, evaporation and storage of produced w ater, m an-

agem ent of w orkover/com pletion fluids and for em ergency containm ent

of produced fluids.

In general, pits should be as sm all as possible and be strategically located

to prevent spillage of w aste m aterials onto the drilling or production site.

Pits should be lined unless site characteristics ensure that there w ill be no

significant threat to w ater resources. In areas w here it m ay be necessary

to construct pits adjacent to w ater bodies or on sloping terrain, special

engineering precautions should be taken to ensure the integrity of the pit.

Free hydrocarbons should be rem oved from pits and returned to the pro-

duction process for recovery as soon as possible, and precautions should

be taken to prevent pit disposal of chem icals, refuse, debris or any other

m aterials w hich w ere originally not intended to be placed in pits. Thesem aterials can alter the nature of the bulk fluids in the pit and m ake dispos-

al m ore difficult.

A lthough pits are an accepted com ponent of E& P operations, they could

represent an environm ental liability if m anaged im properly. Pits should be

for tem porary use, and should not be used for disposal of oil. Pits should

be closed as soon as p racticable and their closure should follow the

required or generally accepted practices of the region.

Solvent extraction uses solvents to extract oil from oily solids or sludges.

Solvents used for extraction include carbon dioxide, propane, hexane, tri-

ethylam ine, m ethylene chloride and certain proprietary solvent m ixtures.

A n elaborate solvent recovery system is generally em ployed in order to

reuse the solvent.

22


Pit M anagem ent

Solvent Extraction



A properly operated solvent extraction system w ill recover and recycle vir-

tually all solvent used for extraction, and allow oil to be recovered. A

closed loop system for the vapour phases generated should ensure that

there are no direct air em issions from the process. Safety w ill be a consid-

eration for system s w hich use high tem peratures, high pressu res or

volatile solvents.

D isposal options for w astew ater separated from the solids, and the treat-

ed solids, w ill de pe nd on the constitue nts of the treated stream s.

Extracted w ater m ay be injected or require treatm ent prior to discharge.

Treated solids m ay be heat treated to rem ove residual solvents prior to

disposal. Solids w ith significant biologically available m etal contents m ay

be stabilised to prevent m igration after disposal.

23




A PPEN D IX 1

A R eview of Solidification/Stabilisation Technology, W iles, C. C .,Journal of

H azardous M aterials,14 (1987), 5–21.

A n E valuation of O rgan ic M aterials that Interfere w ith

Stabilisation/Solidification Processes, in Petroleum C ontam inated Soils,

Volum e I, R em ediation Techniques, Environm ental Fate, R isk A ssessm ent.

C ullinane, M . J., Jr. and B ricka, R . M ., (Kostecki, P. T. and C alabrese, E. J.,

eds.) Lew is Publishers, C helsea, M ichigan, 1989, 127–136.

A P I E nvironm ental G uidance D ocum en t: O nsho re S olid W aste

M anagem ent in E xploration and Production O perations, A PI docum ent

811–10850, January 1989.

C om bustion and Incine ration Processes: A pplications in E nvironm ental

Engineering, N iessen, W . R ., M arcel D ekker, Inc., N ew York, N ew York,1978.

C om posting of C hem ical Industrial W astes P rior to Land A pplication, in

Land Treatm ent of H azardous W aste,W illson, G . B ., Sikora, L. J. and Parr,

J. F., (Parr, J. F., M arsh, P. B . and Kla, J. M ., eds.), N oyes D ata C orp., Park

R idge, N . J., 1983.

C hem ical U sage in O ffshore O il and G as Production System s, H udgins,

C . M ., R eport to A PI, 1989.

E & P Fo rum G uide line s for the P lan ning of D ow nh ole Injec tion

Program m es for O il B ased M ud W astes and A ssociated C uttings from

O ffshore W ells,R eport N o. 2.56/187, O ctober 1993.

E& P Forum O il Industry O perating G uide line for Tropical R ainforests,

R eport N o. 2.49/170, A pril 1991.

Exploration and P roduction Industry A ssociated W aste R eport,A PI docu-

m ent 0300-004-008, M ay 1988.

H andbook for Stabilisation/ Solidification of Hazardous W astes, C ullinane,

M . J., Jones, L. W . and M alone, P. G ., EPA /540/2-86/001, June 1986,

(N TIS no. PB 87-116745).

H and bo ok o f H azardo us W aste Incine ration , B runne r, C . R ., TA BProfessional and R eference B ooks, B lue R idge S um m it, Pennsylvania,

1989.

O il and G as E xploration and Production O perations in M angrove A reas—

G uidelines for Environm ental Protection, W orld C on servation U nion

(IU C N )/E& P Forum joint publication, 19 93, ISB N 2–8317–0187–2, E& P

Forum R eport N o. 2.54/184.

O il and G as Industry Exploration and Production W astes, A PI docum ent

471-01-09, July 1987.

O il and G as E xploration and Production in A rctic and Sub-A rctic O nshore

R egions—G uidelines for Environm ental Protection, W orld C onservation

U nion (IU C N )/E& P Forum joint publication, 1993, ISB N 2–8317–0188–0,

E& P Forum R eport N o. 2.55/185.

24


R eferences



O ilfield Environm ental C ontrol Technology: A Synopsis. W ojtanow icz, A . K.

Journal of Petroleum Technology,166–173, February 1993.

O nsite Treatm ent: H ydrocarbo n C on tam inated S oil, W estern S tatesPetroleum A ssociation, 1990.

Production W aste M anage m ent H andbook for the A lberta Petroleum

Industry,C anadian P etroleum A ssociation, D ecem ber 1990.

S olid-W aste D isposal: D ee p W ell Injection , S m ith, M . E ., C hem ical

Engineering,A pril 9, 1979, 107–112.

Th e E ffect of V olatile O rgan ic C om po un ds on the A bility o f

Solidification/Stabilisation Technologies to A ttenuate M obile P ollutants,

Kyles, J. H ., M alinow ski, K. C ., Leithner, J. S. and Stanczyk, T. F., in

P rocee dings of the N ation al C onference o n H azardo us W astes an d H azardous M aterials,H M C R I (1987), 152–157.

25

APPEN D IX 1



A PPEN D IX 2

acidising The treatm ent of a w ell by injection w ith a solution

of acid (hydrochloric, hydrofluoric, acetic, form ic, cit-

ric) to m aintain or increase perm eability of a rockstratum by dissolving pore blockage due to fine parti-

cles from the reservoir stratum , precipitated m ateri-

als or corrosion products, so im proving productivity

or injectivity (see ‘injection’) of a w ell.

annulus The space surrounding a cylindrical object w ithin a

cylinder; the space around a pipe in a w ellbore, the

outer w all of w hich m ay be the w all of either the

bo reh ole or the casing , som etim es term ed the

annular space.

aquifers R ock strata w hich contain, and are p erm eable to,w ater. The w ater m ay be fresh or saline, and either

potable or non-potable.

BTEX B enzene, Toluene, Ethylbenzene and ortho-, m eta-,

and para-Xylene.

biologically available A lso bio-available. Substances w hich are present in a

form w hich can be taken up by plants or anim als and

w hich m ay be incorporated into their tissues.

biocides M aterials w hich can be added to m uds or reinjected

produced w ater for the purpose of prevention or lim -

itation of grow th of bacteria in the m ud or in the oil-reservoir rock.

biodegradable Susceptible to breakdow n, into sim pler—often solu-

ble and/or gaseous—com pou nds, by m icroorgan-

ism s in the soil, w ater and atm osphere. B iodegrad-

ation often converts toxic organic com pounds into

non- or less-toxic substances.

B O D (biochem ical M ea sure of the qu antity o f disso lved oxy ge n

oxygen dem and) (exp resse d in parts p er m illion) use d in the

de com po sition of organic m atter by bioche m ical

action.

brine Salt w ater. M ay be produced w ater or m ixed solutions

m ost com m only containing sodium , potassium , or cal-

cium chloride salts. W hen added to drilling m uds, brine

has three functions: 1. m inim ise reaction betw een

m ud and soluble salts in the strata being drilled; 2.

increase m ud w eight; 3. increase m ud viscosity.

C FC C hlorofluorocarbon.

consolidation C hem ical m ixture pum ped dow n a w ell to stabilise

m aterials the form ation structure or m inim ise w ater production.

com pletion fluid C hem ical m ixture present in the w ell du ring the

placem ent of production tubing and perforation of

the w ell (m ay be a drilling fluid, or specialised brine).

26


G lossary of O il Industry Term s



cuttings The fragm ents of rock dislodged by the drilling bit

and brought to the surface in the drilling m ud.

developm ent w ell W ell drilled in a form ation for the purpose of produc-

ing oil and gas. A lso called a production w ell.

drilling C hem icals used in the form ulation and m aintenance

chem icals of drilling m uds.

drilling fluids Specialised fluid m ade up of a m ixture of clays, w ater

(and som etim es oil) and chem icals, w hich is pum ped

dow n a w ell during drilling operations to cool and lubri-

cate the system , rem ove cuttings and control pressure.

drilling m uds See drilling fluids .

drilling rig See rig .

decom m issioning The act of taking an operating site out of service.

This m ay include the final plugging of w ells and the

rem oval of surface structures.

descalers Substances added to prevent build-up of, and to a

lesser extent rem ove, solids such as calcium carbon-

ates and sulphates deposited on the drill pipe and

casing. Pitting corrosion of m etal can occur under

scale deposits.

dow nhole D ow n a w ell or borehole.

Environm ental A form al, w ritten, technical evaluation of potential

Im pact effects o n the en viron m en t (atm osp here, w ater,

Assessm ent land, plants and anim als) of a particular event or

activity.

effluents Liquid w aste m aterials discharged from operations.

encapsulation The enclosure of w astes by a non -perm eable sub-

stance. W aste constitue nts are n ot che m ically

altered, but their transport w ill be im peded by the

encapsulating m atrix.

exploration The search for reservoirs o f oil and gas, w hichincludes aerial and geophysical surveys, geological

studies, core testing and drilling of w ells.

exploration D rilling carried out to determ ine w hether hydrocarbons

drilling are present in a particular area or geological structure or

to learn m ore about subsurface structures.

fracturing The process of cracking open, by applying hydraulic

pressure, the rock form ation around a w ell bore to

increase productivity or injectivity.

fracturing fluid H eavy, viscous fluid pum ped dow n a w ell under high

pressure to fracture the target form ation in order to

enhance fluid flow .

27

APPEN D IX 2



flaring C ontrolled disposal of surplus com bustible vapours

by igniting them in the atm osphere.

gas processing The separation of constituents from natural gas for

the purpose of m aking saleable products and also for

im proving the quality of the natural gas.

HCFC H ydrochlorofluorocarbon.

H 2 S (hydrogen A pungent, corrosive, toxic gas occurring naturally in

sulphide) so m e o il an d g as rese rvo irs (an d e lse w here),

ge nerated by the m etabo lism of certain type s of

bacteria.

hydrotest The checking of the integrity of a container (e.g. a

tank or pipe) by filling it w ith w ater under pressure

and testing for any loss of pressure.

injection w ell A w ell used to inject gas o r w ater into an oil/gas

reservoir rock to m aintain reservoir pressure during

the secondary recovery process. A lso a w ell used to

inject treated w astes into selected form ations for

disposal.

M SDS/SDS M aterial Safety D ata Sheet used by chem ical suppli-

ers to sum m arise properties of products, including

health, safety and environm ental aspects.

N O R M N aturally O ccurring R adioactive M aterials. Low

Specific A ctivity (LSA ) scale is o ne exam ple of a

NO RM w aste.

PA H Polynuclear A rom atic H ydrocarbon.

produced w ater W ater originating from the natural oil reservoir, that

is separated from the oil and gas in the production

facility.

production That phase of petroleum operations that deals w ith

bringing the reservoir fluids to the surface and sepa-

rating them , and w ith storing, gauging, and other-

w ise preparing the product for the pipeline.

production C hem icals used to enhance or assist the production

treating chem icals process or protect equipm ent.

reclam ation The activities undertaken to restore a site to a prede-

term ined land-use.

recoverable That proportion of the oil/gas in a reservoir that can

reserves be rem oved using currently available techniques.

rig A collective term used to describe the equipm ent,

including the vessel or structure on w hich the equip-

m ent is installed, required to drill a w ell, the m ost

visible com ponent being the m ast or derrick.

28




road oil O il used for dust control or road base stabilisation,

generally spread on the road and incorporated by till-

ing and com paction.

scrubbing Purifying gas by treatm ent w ith a w ater or chem ical

w ash.

seism ic survey A survey conducted to m ap the depths and contours

of rock strata by tim ing the reflections o f sound

w aves released from the surface or from dow n a

borehole (shot hole).

shot hole A borehole in w hich an explosive is placed for blast-

ing in use as the energy source for seism ic survey.

solidification The addition of m aterials (saw dust, adsorbent poly-

m ers, etc.) to a w aste to change its physical state and

im prove handling and w eight-bearing characteristics.

stabilisation The chem ical conversion or encapsulation of w aste

to create a com posite m atrix that resists leaching.

stim ulation fluids C hem ical m ixture pum ped dow n a w ell to stim ulate

or enhance the production of hydrocarbons from that

w ell.

vent gases Th ose gases w hich are released , un bu rnt to the

atm osphere. Venting m ay be deliberate (for opera-

tional reasons) or accidental.

Vibroseis A com m ercial heavy, vehicle-m ounted, vibration sys-

tem used onshore for the generation of shock (sound)

w aves into the ground during seism ic surveys.

VO C Volatile O rganic Com pounds.

w ater injection The pum ping of w ater into the reservoir rock to m ain-

tain the reservoir pressure.

w ell com pletion The activities and m ethods used to prepare a w ell for

the production of oil and gas. This m ay include estab-

lishm ent of a flow line betw een reservoir and sur-

face.

w ell servicing The m aintenance w ork perform ed on an oil or gas

w ell to im prove or m aintain the production from a

form ation already producing.

w ellbore The hole m ade by drilling or boring; m ay have a cas-

ing in it or it m ay be open, or a portion m ay be cased.

w orkover A process by w hich a com pleted production w ell is

subsequently re-entered and any necessary cleaning,

repair and m aintenance w ork done.

29

APPEN D IX 2



A PPEN D IX 3

The follow ing form is an exam ple of a w orksheet w hich could be used

w hen developing area w aste m anagem ent plans. C om pletion of such

form s requires input from personnel w ho are fam iliar w ith both operationaland technical aspects of E& P activities. To ensure consistency, proce-

dures used to classify w astes should be defined before com pleting a

w orksheet. These classifications should agree w ith any local regulatory

agency definitions.

The space for specifying the operation/equipm ent generating the w aste

can be used to docum ent the incident or event causing w aste generation.

Exam ples include periodic tank cleaning, spills and leaks. Exam ination of

these records m ay then assist in identifying process or procedure m odifi-

cations to reduce or elim inate w astes. C om pletion of other table item s is

outlined in the legend below .

To determ ine how you w ant to m anage your w aste, list the w astes you

generate, their sources (e.g. operation or equipm ent), volum es (e.g. bbls,

m 3 or tons), frequency of generation (e.g. per day, per w eek, per year),

know n hazardous characteristics (e.g. pH < 2), and classification (degree of

hazard). D escribe the current w aste disposal practices (e.g. onsite or off-

site, disposal m ethod used and nam e of disposal facility). List all the alter-

native w aste m anag em en t op tion s (e.g. m inim isation, road and land

spreading, burial, injection) and record any special constraints that affect

your options. Taking everything into consideration, choose the preferred

m anagem ent option.

30


W aste M anagem ent Planning W orksheet



3 1

WASTE MANAGEMENT PLANNING WORKSHEET

A

WasteManagement

Options

Current Disposal

Onsite/

Offsite

Disposal

Method

Facility

Name

Waste

Classification

Waste

Characteristics

Frequencyof

Generation

Waste

Volume

Operation/

Equipment

Generating

Waste

Waste

DATE: / / LOC ATION: PERSON PREPA RING WORKSHEET:



A PPEN D IX 4

The follow ing table su m m arises the prim ary types of w aste stream s

encountered during E& P operations. The m ain sources of these stream s

are provided for clarification. The constituents that m ay be of environm en-tal concern are also sum m arised for each w aste. The inclusion of a con-

stituent in this colum n does not necessarily indicate that the constituent is

alw ays present, or that if the constituent is present that it w ill be of high

enough concentration to w arrant concern. The last colum n of the table

indicates w hich of the individual E& P activities m ay generate the indicated

w aste stream .

32


Sum m ary of W astes

G enerated by E & P A ctivities

A = A bandonm ent C = C onstruction and C om m issioning D = D rilling M = M aintenance P = Production S = Seism ic

WA STE STREA M MA IN SOURC ES POSSIBLE ENVIRONMENTA LLY TYPE OF

SIGNIFIC A NT C ONS TITUENTS OPERA TION

A bsorbents Spill clean up H ydrocarbons, production chem icals, solvents A C D M P S

A ir Em issions Vent gases N O x, SO x, H 2S, C O x, VO C , D P

Flare G ases hydrocarbons, carbon, particulates,

B low dow n from bulk chem icals PA H 's, B TEX

A ir Em issions Engine exhausts C O x, SO x, N O x, VO C, PAH s, A C D M P S

form aldehyde, carbon particulates

A ir Em issions Fugitive gases VO C , B TEX A C D M P

B allast w ater Tankers w ith non-segregated H ydrocarbons P

ballast

B oiler/cooling tow er Steam generation facilities Scale inhibitors, biocides, corrosion inhibitors, D M

blow dow n and cooling tow ers heavy m etals, solids

C em ent C em ent slurries H eavy m etals, thinners, viscosifiers, pH , salts D P

C em ent m ix w ater

C em ent returns

C onsolidation C arrier fluids H ydrocarbons P

m aterials Epoxy resins Excess chem icals

C ontam inated soil Spill/leaks H ydrocarbons, heavy m etals, salts, A C D M P S

treating chem icals

C ontam inated R ainw ater run-off Inorganic salts, heavy m etals, solids, A C D M P

drainage w ater R ig w ash production chem icals, detergent,

Process w ater hydrocarbons

W ash w ater

D ehydration and D ehydration processes A m ines, glycols, filter sludges, m etal sulphides,

Sw eetening W astes Sw eetening processes H 2S, m etals, benzene P



33

APPEN D IX 4

WA STE STREA M MA IN SOURC ES POSSIBLE ENVIRONMENTA LLY TYPE OF

SIGNIFIC A NT CONSTITUENTS OPERA TION

D om estic sew age Living quarters B O D , solids, detergent, coliform bacteria A C D M P S

D rilling fluid C hem ical containers B iocides, surfactants, salts, m etals, em ulsifiers, D P

chem icals D rilling fluids viscosifiers, organics, pH

D rill cuttings

R ig w ash

Fire fighting agents Fire protection H alons, C FC s, H C FC s, fire fighting foam s A C D M P

equipm ent/facilities

H ydrotest fluids Pipeline hydrotesting activities B O D , solids, biocides, corrosion inhibitors, C

oxygen scavengers, dyes

Incinerator ash Incinerators H eavy m etals, salts, ash A D P

Industrial refuse C leaning m aterials H ydrocarbons, plastic A C M

Insulation

Industrial w aste B atteries A cid, alkali, heavy m etals, PC B s A C M

Transform ers

C apacitors

M aintenance w astes Sandblast (grits) H eavy m etals, hydrocarbons, solids, solvents M

G reases

Fuel oils

Filters

M edical w aste D ressings Pathogenic organism s, plastic, glass, A C D M P

C linical & cleaning m aterials m edicines, needles

B lood sam ples

M ercury Instrum entation M ercury A D M P

O il/gas production

Production testing

O il based m uds D rilling operations H ydrocarbons, inorganic salts, heavy m etals, D

& cuttings solids/cuttings, drilling fluid chem icals

Paint m aterials Paints H eavy m etals, solvent, hydrocarbon C M

Thinners

C oatings

Pigging sludges Pipeline cleaning operations Inorganic salts, heavy m etals, solids, P

production chem icals, N O R M , hydrocarbons,

phenols, arom atics

Process w ater Engine cooling w ater H ydrocarbons, treatm ent chem icals A D M P S

B rake cooling w ater

W ash w ater

A = A bandonm ent C = C onstruction and C om m issioning D = D rilling M = M aintenance P = Production S = Seism ic





35

APPEN D IX 5

A PPEN D IX 5

The follow ing pages contain descriptions of som e selected w aste stream s

and discussion of possible w aste m anagem ent options for these w astes.

These descriptions are not intended to be all-inclusive but give exam plesof potential options.

A tm ospheric Em issions

This covers all pow er plant exhausts, flares, vents and gas leaks in drilling

and oil and gas processing activities.

This can include SO x, N O x, H 2S, hydrocarbo ns, VO C s, particulates and

PAHs.

Waste Management Options

Reduce: D esign and operate oil and gas exploration and productionactivities and process equipm ent w ith controls and policies

to m inim ise atm ospheric em issions.

M aintain and run all pow er plants under optim al fuel effi-

cient conditions, w hen possible.

Reuse: W here possible flare gas should be used as a fuel. N atural

gas m ay also be injected for reservoir m aintenance,

enhanced recovery or used in artificial lift.

R ecycle/ E xp loit w aste h eat reco ve ry op portunities w he re

R ecover: practically possible.

Treatm ent/ Excess produced gas m ay be injected or flared.

D isposal:

C atalytic cham bers, scrubbers or strippers can be installed

on exhaust stacks.

W ater injection into fuel com bustion cham bers m ay reduce

N O x em issions.

C hem ical W aste

This includes any surplus or contam inated chem icals used at all stages of

exploration and production activities. It includes specific item s such as bat-teries, transform ers and o ther item s containing or contam inated w ith

chem ical products.

The concerns w ill depend on the com position and the associated safety

and adverse environm ental considerations. These w astes m ay require spe-

cific segregation and disposal techniques.


Reduce: W herever possible, planning and good housekeeping practices

should be em ployed to m inim ise surplus and contam ination.

Substitution w ith longer life products and those w ith low er

im pacts should be considered.

Specific W aste Inform ation



36


Reuse: Surplus chem icals m ay b e usable in othe r location s o r

returned to vendors, if possible.

M aterials such as cem ent, bentonite, lim e, m ay have alter-

nate use in w aste treatm ent, road construction, landfill site

construction, etc.

R ecycle/ Item s such as lead acid batteries, w et nickel/cadm ium

R ecover: batteries should be sent to recycling facilities if available.

C ertain chem ical w astes m ay contain m etals such as silver

or m ercury w hich could be recovered.

C hem ical solvents m ay be econom ically recovered or used

in a fuel blending program m e.

Treatm ent/ Encapsulation/solidification by m ixing w ith cem ent, lim e or

D isposal: other binder m ay be appropriate prior to disposal.

Special landfill sites m ay be available w hich can accept cer-

tain kinds of chem ical w aste. The possibility of leachate

problem s need to be identified.

For som e o rganic chem ical w astes, incineration m ay be

the preferred treatm ent option. For chem icals like PC B s,

high tem perature incineration is required to destroy the

com pounds.

C ontam inated S oil from O il/Fuel Spills

This m ay include soil, beach or shore m aterials arising from the leakage or

spill of hydrocarbons or fuels.

The im pact w ill depend on the type of hydrocarbon and the location of the

spill or leak.


Reduce: A void spills and leakage by im proved housekeeping, m ain-

tenance and transport procedures.

Reuse: N /A

R ecycle/ D epending on the extent of the contam ination, recovery ofR ecover: free liquids m ay be possible.

Treatm ent/ Land farm ing , landsp reading and com po sting m ay be

D isposal: ap plicable if conditions for biological degrad ation are

favourable. Enhancem ent techniques could be considered.

Incineration, landfill and burial options m ay be lim ited by

availability and the quantity/nature of the contam inated soil.

Stabilisation techniques m ay be applicable prior to disposal.



D rilling Pit W aste

D rilling pit w astes usually contain both solid and liquid com ponents.

C onstituents of environm ental concern include salt, hydrocarbons, pH ,

drilling chem icals and biologically available heavy m etals. These con-

stituents have the possibility of im pacting soil and w ater quality.


Reduce: The volum e of drilling pit w astes m ay be reduced by judi-

cious use of rig w ash w ater, by releasing w ater that does

not contain hydrocarbons or high salinity from the pit, by

avoiding the collection of rainw ater run-off in the pit or by

reusing the w ater in the drilling fluid.

D rilling w aste volum e m ay be m inim ised by the use of a

closed loop m ud system .

Reuse: Solids m ay be applicable for the lining or capping of landfill

sites, or as a road construction m aterial.

R ecycle/ R ecovered w eighting m aterials and drilling fluids m ay be

R ecover: recycled into the drilling fluid of the sam e or different w ell.

C om m ercial m ud plants m ay take used drilling fluids for

recycle.

Treatm ent/ O ptions for the disposal of aqueous d rilling pit w astes

D isposal: include surface discharge and injection. Before the aque-

ous phase can be surface discharged, it should be treated

to rem ove hydrocarbons and excess suspended solids and

to adjust the pH to w ithin the acceptable range. The dis-

solved salt and biologically available m etal content m ust

be at a level w hich w ill not cause an adverse im pact on

the receiving environm ent. Liquids w hich cannot be treat-

ed to a standard suitable for surface discharge m ay have

to be injected.

The option s for m anagem en t of solid drilling pit w astes

include burial in the pit; landfarm ing, landspreading or com -

posting to reduce organic content; therm al treatm ents to

recover or destroy organics; injection; and stabilisation or

solidification.

D rum s/C ontainers

M etal and plastic containers are used for a w ide range of lubricants and

chem icals used throughout the industry. The accum ulation and disposal of

these can be problem atic. D rum s and containers inevitably contain variable

quantities of residues. The im pact arises from both the volum e and pres-

ence of residues.

Waste Management options

Reduce: B ulk transport and storage should be considered for high

volum e consum ption item s.

Reuse: C ertain containers can be refilled from bulk storage and

reused. W here possible, non-refillable containers should be

returned to the vendor for reuse, or to a com pany specialis-

ing in container refurbishm ent.

37

APPEN D IX 5



D rum s and containers can be used for the transportation of

suitable w astes provided safety considerations are not

com prom ised.

R ecycle/ B oth m etal and certain plastic drum s and containers m ay

R ecover: be recycled if outlets are available. H ow ever, this m ayrequire that they be cleaned of any residues beforehand.

Treatm ent/ D rum s should be crushed prior to landfill. The nature of

D isposal: any residues m ay restrict this option or require pre-cleaning.

Incineration m ay be applicable to plastic containers, but

incinerators m ay need to be equipped w ith air pollution

control devices.

G arbage–Inert Solid W aste

This includes w ood, plastics, paper, food w aste, general garbage and inert

construction and m aintenance m aterials.

The environm ental im pact m ay arise from the encouragem ent of verm in

by food w astes, produ ction of gases by biod eg radable m aterials and

leachates w here other site m aterials such as chem ical residues have been

m ixed in w ith the w aste.


Reduce: P ackaging w astes such as pap er and plastic can be

reduced by the use of bulk handling system s or ‘big bags’.

Segregation of com ponents such as w ood, plastic and paper,

for recycling or reuse w ill reduce the quantity for disposal.

Reuse: W here the inert w aste consists totally of construction

m aterial, it m ay be usable as infill.

R ecycle/ M aterials such as w ood , pape r and m etals m ay be

R ecover: segregated for recycling.

G eneral garbage is frequently incinerated and som e inciner-

ators are fitted w ith heat recovery.

Treatm ent/ Land fill is the m ost com m on disposal m ethod em p-D isposal: loyed. Local conditions m ay lim it this option. B urial of these

w astes m ay b e an o ption w he n a suitable landfill is

not available.

Incineration using fixe d or m obile facilities w ill greatly

reduce the w aste volum e for landfill.

Techniques such as com posting m ay be used to reduce the

volum e of dom estic w aste through biodegradation.

Pit, Tank and V essel B ottom W astes

This w aste consists of w ater, accum ulated hydrocarbons, solids, sand and

em ulsions w hich collect in the low er sections of slop oil tanks, crude oil

stock tanks, closed w ater drain tanks, open w ater drain tanks and other

38




storage and separation vessels as w ell as in produced w ater storage or

em ergency pits.

C onstituents of these w astes that m ay im pact selection of w aste m anage-

m ent and disposal m ethods include hydrocarbons, salts, m etals, produc-

tion chem icals and occasionally N O R M . Possible environm ental im pactsw ill depend on the concentrations of these constituents and the w aste

m anagem ent option(s) chosen.


Reduce: Im proved housekeeping procedures m ay reduce the volum e

of solids collected in drainage w ater storage tanks. The w aste

volum e m ay be reduced through evaporation or dew atering.

Reuse: Suitable w astes m ay be m ixed w ith absorbent m aterial (e.g.

lim e) and applied as road surfacing m aterial, or m ixed w ith

aggregate in an asphalt batch process.

R ecycle/ S ludges containing sign ifican t oil m ay be reclaim ed

R ecover: either onsite or offsite for the rem oval and recovery of

hydrocarbons.

Treatm ent/ These sludges m ay be landfilled, if dry.

D isposal:

Th ese slud ge s m ay be land spread o r land farm ed .

C onsideration w ill have to be m ade of the biodegradability

of the organics, availability of land, loading rates, and possi-

bility of ground or surface w ater contam ination.

These sludges m ay be incinerated, w ith prope r pollution

control devices in place.

Process D rainage W aste System

The process facility drainage system w astes w ill include w ashdow n w ater,

boiler and cooling w ater blow dow ns, leaks and spills. The hazards w ill

depend on the nature of the sources. A s w ith surface w ater drainage,

physical effects such as erosion and tem perature m ay be considerations.


Reduce: A leak m inim isation strategy should form an integral part of

facility design and m aintenance procedures. A ll fuel, hydro-

carbon and hazardous chem ical storage areas should be suf-ficiently bunded. D rip pans should be used w here needed.

Spill clean-up procedures should be developed.

Reuse: Process w ater m ay be reused for activities requiring low er

w ater quality (e.g. rig w ashing or flare suppression).

R ecycle/ N /A

R ecover:

Treatm ent/ See rainw ater drainage

D isposal:

39

APPEN D IX 5



Produced W ater

O riginating from oil and gas production/processing, produced w ater w ill

contain variable quantities of m ineral salts, solids, suspended and dis-

solved hydrocarbons, and other organic and inorganic com ponents, and

m ay be at high tem perature. The com position m ay change w ith tim e. It

m ay require pre-treatm ent prior to disposal.

Th e environm ental im pact w ill be highly de pen den t on the quantities

involved, the com ponents, the receiving environm ent and dispersion char-

acteristics.

B efore significant or long-term discharge of produced w ater to the environ-

m ent is carried out, an environm ental im pact study should be carried out.


Reduce: W ater shut off treatm ents, re-perforation.

Reuse: R e-injection for reservoir pressure m aintenance or sec-ondary recovery of oil.

Q uality m ay allow use for agricultural purposes or reuse as

w ash w ater.

R ecycle/ H eat content.

R ecover: D e-salination.

Treatm ent/ Surface discharge into the environm ent m ay be possible

D isposal: depending on the w ater quality, volum e and flow . Prim ary

treatm ent such as de-oiling w ill often be required. B io-treat-

m ent m ay be practical for low volum es.

D ow nhole injection to suitable form ations other than the

producing form ation m ay be possible. H ow ever, the possi-

bility of contam inating usable w ater aquifers m ust be taken

into account.

Evaporation and subsequent disposal of salts m ay be possible.

R ainw ater D rainage

This w ill com e from all areas of the site/facilities. Surface drainage w ill be

susceptible to contam ination from spills, leakage and leaching. The envir-

onm ental im pact w ill depend on such contam ination along w ith physicalconsiderations such as erosion.


Reduce: C on tam ination of the surface drainage w ater should b e

avoided as this w ill be considerably easier than any subse-

quent treatm ent. Thought should be given to the segregation

of drainage from liquid storage, loading/unloading facilities,

and operations areas from unim pacted areas of the site.

Reuse: C ollected rainw ater could be reused for agricultural purpos-

es if quality perm its or could be used for activities requiring

low er w ater quality such as w ashing or flare suppression.

R ecycle/ N /A

R ecover:

40




Treatm ent/ Surface disposal m ay be governed by contam ination. The

D isposal: provision of a site drainage system w ith an oil/so lids

interceptor shou ld be conside red . A ny surface disposal

option should be capable of taking the drainage volum es

w itho ut causing dam age by erosion or floo ding , w hich

w ould not otherw ise occur.

D rainage w ater w ith a high organic content m ay be treated

in biological w ater treatm ent system s to rem ove organics

prior to discharge.

Sanitary W aste

This covers all sew age and foul drainage. The im pact w ill be associated

w ith the B O D , C oliform bacteria and treatm ent chem icals.


Reduce: Low flow and low w ater use toilets m ay be used.

Reuse: N /A

R ecycle/ D igested sew age sludge m ay be used for agricultural/land

R ecover: im provem ent purposes.

Treatm ent/ Full treatm ent septic system s to process all sew age should

D isposal: be installed for all construction, drilling and production facili-

ties, and cam ps on land. C onsideration m ay be required for

m arine sew age system s for large offshore rig or platform

operations.

If chlorination is carried out, this should be strictly controlled

and oxygenation m ay be required to prevent dam age to

aquatic life.

41

APPEN D IX 5



A PPEN D IX 6

This table sum m arises the w aste m inim isation options and possible treat-

m ent and disposal m ethods that m ay be applicable to a variety of w astes

typically found in E& P operations.

This list is not exhaustive, and the m inim isation, treatm ent and disposal

m ethods m ay vary according to available facilities, local conditions and

regulatory requirem ents. Indication in the table that m inim isation options

m ay exist does not necessarily m ean that a significant reduction in w aste

volum e can be reasonably achieved. Sim ilarly, indication that a treatm ent

or disposal option m ay be applicable does not necessarily m ean that it w ill

be appropriate or effective for specific w aste stream s or all environm ents.

C om binations of treatm ent and disposal m ethods m ay be required to

m eet m anagem ent objectives.

42


W aste M anagem ent O ptions—

Sum m ary Table

Treatment and Disposal Methods

A = D eep W ell, B = Evaporation Ponds, C = Specialised W aste D isposal Facility, D = Incineration, E = Land Treatm ent,

F = Landfill, G = B iological Treatm ent, H = R oad A pplication, I = Solidification, J = B iorem ediation, K = Surface W ater

D ischarge (m ay require pretreatm ent)

Minim isation Options Treatm ent and Disposal Method

Waste Name Reduc e Reuse Rec yc le A B C D E F G H I J K

A cid

A ctivated C arbon

B atteries, Lead A cid,

W et N ICA D

C atalysts

C austic

C hem ical W aste

C onstruction & D em olition

M aterial

C ontainers—D rum s/B arrels

C ontam inated D ebris

& Soil—Chem icals

C ontam inated S oil—

H ydrocarbon/Fuel

D essicant

D rilling Pit W aste

Filter B ackw ash Liquids

Filters, C hem ical Treatm ent



APPEN D IX 6

Minim isation Options Treatm ent and Disposal Method

Waste Nam e Reduc e Reuse Recyc le A B C D E F G H I J K

Filters—Lube O il

Filters—O ther (R aw gas,

fuel, air)

Filters—W ater

G arbage—Dom estic W aste

H ydrotest Fluids

Incinerator Ash

Insulation

Ion E xchange R esins

Ion E xchange R esin—

R egenerant Liquids

Iron Sponge

Laboratory C hem icals

Lubricating O il—

H ydrocarbon

Lubricating O il—Synthetic

M olecular Sieve

Paint A ssociated W astes

PC B—Contam inated Solids

& Liquids

Pigging W aste Liquids/W ax

Process W aters

Produced Sand

Produced W ater

R ags—O ily

R ainw ater D rainage

Scrap M etal

Sludge, G lycol system s

Sludge, G as Sw eetening

Sludge, Tank & Vessel

B ottom s

Sludge, W ater Treatm ent

Sanitary W astes

Documents

Exploration and Production (E&P) Waste Management Guidelines