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DEP Regulatory Requirements Chapter 78 Subchapter D

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Title: DEP Regulatory Requirements Chapter 78 Subchapter D


1
DEP Regulatory RequirementsChapter 78 Subchapter
D
  • Dave English
  • Division of Compliance and Data Management
  • Bureau of Oil and Gas Management

2
Focus
  • Significant changes to Subchapter D.
  • Relevant revisions to Subchapters A, C, and E

3
Oil and Gas Wells and the Middle Devonian
Marcellus Formation
4
Chapter 78 Subchapter D addresses
  • New well drilling, casing, cementing, completion
    and operational practices

5
Chapter 78 Subchapter D addresses
  • Currently operating oil and gas wells

6
Chapter 78 Subchapter D addresses
  • Plugging abandoned wells

7
Rationale for Proposed Rulemaking Needs
Assessment
  • New drilling and completion practices used to
    develop Marcellus and other unconventional
    formations
  • Stray gas migration incidents (Marcellus and
    shallow oil and gas wells)
  • Well control incidents (e.g. EOG incident June 3,
    2010 in Clearfield County)
  • Hydraulic fracturing additive disclosure
  • Mandatory production reporting Act 15

8
Final Rulemaking 25 Pa. Code Chapter 78
Background
  • Initial draft presented to TAB September 17, 2009
  • DEP met with TAB and subcommittee four additional
    times (10/28/09, 1/14/10, 1/21/10, 3/25/10)
  • Advanced Notice of Proposed Rulemaking Public
    comment period January 30, 2010 March 2, 2010
  • Notice of Final Rulemaking Public comment period
    July 10, 2010 August 9, 2010
  • Approval by EQB, IRRC, Attorney Generals Office.
  • Final Regulations approved on publication in the
    Pennsylvania Bulletin February 5, 2011

9
Final Rulemaking 25 Pa. Code Chapter 78
Significant Revisions
  • Well Control
  • Well Construction (casing and cementing
    operations)
  • Mechanical Integrity of Existing Wells
  • Gas Migration Response
  • Well Reporting

10
Future Rulemaking Next Regulatory Package
  • Revisions to Plugging regulations 78.91-78.98
  • Revisions to Subchapter C Environmental
    Protection Performance Standards
  • Other revisions and modifications, i.e.,
    tweaks to Subchapter D

11
Chapter 78. Oil and Gas Wells
  • Subchapter A General Provisions

12
Chapter 78. Oil and Gas Wells
  • Subchapter A General Provisions new
    definitions added
  • Conductor pipe
  • Intermediate casing
  • L.E.L. (lower explosive limit)
  • Unconventional formations

13
Chapter 78. Oil and Gas Wells
  • Subchapter C Environmental Protection
    Performance Standards

14
78.55. Control and Disposal Plan
  • Plan must include operators pressure barrier
    policy that identifies barriers to be used during
    specific operations
  • Plan must be available at the well site for
    review during drilling and completion activities
  • List of emergency contact phone numbers for the
    area in which the site is located must be
    prominently displayed at the well site during
    drilling, completion, and workover activities

15
Chapter 78. Oil and Gas Wells
  • Subchapter D Well Drilling, Operation and
    Plugging

16
78.72 Use of Safety Devices BOP Equipment(New
language in italics)
  • BOP equipment to be used
  • When drilling well intended to produce natural
    gas from an unconventional formation
  • When drilling out frac plugs
  • Where pressures are anticipated at the well site
    that may result in a loss of well control
  • Where operator is drilling in an area where there
    is no prior knowledge of pressure or natural open
    flow
  • When drilling conservation wells
  • When drilling within 200 feet of a building

17
78.72 Use of Safety Devices BOP Equipment
  • Controls for the blow-out preventer must be
    accessible to allow actuation of the equipment
  • Additional controls for the BOP with a pressure
    rating of 3000 psi, not associated with the rig
    hydraulic system, must be located at least 50 ft.
    away from the drilling rig such that the BOP can
    be activated if control of the well is lost

18
78.72 Use of Safety Devices BOP Equipment
  • Remote Accumulator for BOP Actuation
  • Close-up of BOP Controls

19
78.72 (d) BOP Equipment Testing
  • Annular-type must test according to the
    manufacturers instructions, or by a professional
    engineer, before placing in service
  • Equipment failing test must not be used until it
    is repaired/replaced and passes the test

20
78.72(d) BOP Equipment Testing
  • Ram-type must test for both pressure and ram
    operation before placing in service on the well
  • Testing in accordance with API RP53
  • If not in good working order, drilling must cease
    until BOP equipment is repaired/replaced and
    re-tested

21
78.72 BOP Additional requirements
  • All lines, valves and fittings between the
    closing unit and the BOP stack must be flame
    resistant and have a rated working pressure that
    meets or exceeds the requirements of the BOP
    system
  • When BOP is installed or required, an individual
    must be present at the well site with a current
    certification from a well control course
    accredited by the International Association of
    Drilling Contractors or other organization
    approved by DEP
  • Pressure barriers identified in drilling and
    completions operations requiring two mechanical
    barriers must be capable of being tested. This
    does not mean that all operations utilizing BOP
    equipment must employ two mechanical barriers
  • A stripper barrier or stripper heads are not
    considered adequate barriers
  • A coiled tubing rig or hydraulic workover unit
    with appropriate BOP equipment must be utilized
    during post-completion cleanout operations in
    unconventional formations penetrated by a
    horizontal wellbore
  • DEP will be developing pressure barrier policy

22
Chapter 78 Major Changes to Well Construction and
Cementing and Other Changes to Subchapter D
  • Revised casing standards
  • New requirement for casing and cementing plan
  • New Section on lost circulation
  • Revised cement standards
  • New Section on mechanical integrity of existing
    wells

23
78.73 General Provisions Revised language
  • Operator must construct well in accordance with
    this Chapter and ensure that the integrity of the
    well is maintained and health, safety,
    environment and property are protected
  • Operator must prevent gas, oil, brine, completion
    and servicing fluids, and any other fluids or
    materials from below the casing seat from
    entering fresh groundwater, and shall otherwise
    prevent pollution or diminution of fresh
    groundwater
  • Reduced pressure at surface or coal protective
    casing seat may not exceed 80 of the hydrostatic
    pressure of the surrounding fresh groundwater
    (0.8 X 0.433) X casing length (ft)

24
78.73 General Provisions New Language
  • Excess gas encountered during drilling,
    completion or stimulation must be flared,
    captured or diverted from the drilling rig in a
    manner that does not create a hazard to public
    health or safety
  • Wells must be equipped with a check valve to
    prevent backflow from pipelines into well (except
    gas storage wells)

25
78.75a. New Section Area of Alternative Methods
  • DEP may designate an area of alternative methods
    if it determines that well drilling and operating
    requirements beyond those provided in this
    Chapter are necessary
  • Notice of proposed area of alternative methods
    will be published in PA Bulletin
  • Wells drilled within this area must meet the
    requirements specified by the Department unless
    the operator obtains DEP approval to drill,
    operate or plug the well in a different manner
    that is at least as safe and protective of the
    environment as the requirements in the area of
    alternative methods

26
78.76. Drilling within a Gas Storage Reservoir
  • An operator proposing to drill in a gas storage
    area (or the surrounding reservoir protective
    area.normally 2000 ft) must send a copy of the
    location plat, the drilling/casing/cementing
    plan, and the anticipated date drilling will
    commence to the gas storage reservoir operator
  • New language requires that information above also
    be sent to the Department along with proof of
    notification to the gas storage reservoir
    operator DEP must approve the proposal prior to
    drilling

27
78.81-78.87. Casing and Cementing
28
78.81 General Provisions
  • Casing and cementing must
  • Allow effective control of the well at all times
  • Prevent the migration of gas and other fluids
    into fresh groundwater
  • Prevent the pollution or diminution of fresh
    groundwater
  • Prevent the migration of gas or other fluids into
    coal seams

29
78.82. Use of Conductor Pipe
  • New rulemaking additions
  • Conductor pipe shall be installed in a manner
    that prevents the subsurface infiltration of
    surface water or fluids
  • Conductor pipe shall be made of steel

30
78.83. Surface and Coal Protective Casing and
Cementing Procedures New Language
  • Wells drilled, altered, reconditioned or
    recompleted after final regulations may not
    utilize surface casing, or any casing functioning
    as water protection casing, unless
  • The well is an oil well where the operator does
    not produce any gas generated by the well and the
    annulus between the surface casing and the
    production pipe is left open
  • The operator demonstrates that the pressure in
    the wellbore at the casing seat is no greater
    than the pressure allowed by (new) 78.73(c) (0.8
    X 0.433 psi/ft X casing length (ft). Operator
    must install a working pressure gauge that can be
    inspected by the Department
  • Determination may be with a pressure test to 80
    of the calculated hydrostatic pressure at the
    surface casing seat

31
78.83. Surface and Coal Protective Casing and
Cementing Procedures New Language
  • Surface casing may not be set more than 200 feet
    below the deepest fresh groundwater except as
    necessary to set the casing in consolidated rock
  • Surface casing hole must be drilled using air,
    freshwater, or freshwater-based drilling fluid
  • Wellbore must be conditioned to ensure an
    adequate cement bond between the casing and
    formation prior to cementing
  • Centralizers at least one within 50 ft. of the
    surface casing seat, then in intervals no greater
    than every 150 ft. above the first centralizer

32
78.83. Surface and Coal Protective Casing and
Cementing Procedures New Language
  • Operator must document the depth of the fresh
    groundwater zone in the well and record if
    additional fresh groundwater is encountered below
    the surface casing
  • Coal protective string must have at least two
    centralizers, one within 50 ft. of the casing
    seat and the second within 100 ft. of the surface
  • When cementing in lost circulation zones, using a
    pour string/tremie pipe to cement above the
    cement basket does not constitute permanently
    cementing the surface or coal protective casing
    pursuant to new Section 78.78b (relating to
    Casing and Cementing Lost Circulation)

33
78.83a. Casing and Cementing Plan New Section
  • Operator must prepare a casing and cementing plan
    showing how the well will be drilled and
    completed
  • Plan must include
  • Anticipated depth and thickness of any producing
    formation, expected pressures and anticipated
    fresh groundwater zones, and the method or
    information by which the depth of the deepest
    fresh groundwater was determined (discussed
    later)
  • Diameter of the borehole
  • Casing type, depth, diameter, wall thickness, and
    burst pressure rating
  • Cement type, additives, and estimated amount
  • Estimated location of centralizers
  • Proposed borehole conditioning procedures
  • Alternative methods or materials as required by
    DEP as a condition of the well permit
  • Plan must be available at the well site for
    review, may be required by the Department for
    review and approval (for permit issuance), and
    any revisions to the plan made as a result of
    on-site modifications must be documented by the
    operator, initialed and dated, and available for
    DEP review

34
Section 78.83a.(a)(1) Methodology for
Determining Deepest Fresh Groundwater
  • Regulatory definition of deepest fresh
    groundwater
  • The deepest fresh groundwater bearing
    formation penetrated by the wellbore as
    determined from drillers logs from the well or
    from other wells in the area surrounding the
    well or from historical records of the normal
    surface casing seat depths in the area
    surrounding the well, whichever is deeper.

Buckwalter Moore (2006)
35
Section 78.83a.(a)(1) Methodology for
Determining Deepest Fresh Groundwater
  • Standard groundwater quality classification
    schemes
  • Fetter (1994)
  • Fresh 0 to 1,000 mg/l TDS
  • Brackish 1,000 to 10,000 mg/l TDS
  • Saline 10,000 to 100,000 mg/l TDS
  • Brine gt100,000 mg/l TDS
  • Quiñones-Aponte Wexler (1995)
  • Fresh lt1,000 mg/l TDS
  • Slightly Saline (brackish) 1,000 to 3,000 mg/l
    TDS
  • Moderately Saline (brackish) 3,000 to 10,000
    mg/l TDS
  • Very Saline (saltwater) 10,000 to 35,000 mg/l
    TDS
  • Brine gt35,000 mg/l TDS

Olsthoorn (2008)
36
Section 78.83a.(a)(1) Methodology for
Determining Deepest Fresh Groundwater
  • Some numerical considerations in Pennsylvania
  • Delaware River Basin Commission (DRBC)
  • Freshwater is water containing less than 1,000
    mg/l of dissolved solids, most often salt.
  • 40 CFR 144.3 United States EPA
  • Underground source of drinking water (USDW)
    means an aquifer or its portion (a)(1) Which
    supplies any public water system or (2) Which
    contains a sufficient quantity of ground water to
    supply a public water system and (i) Currently
    supplies drinking water for human consumption or
    (ii) Contains fewer than 10,000 mg/l total
    dissolved solids and (b) Which is not an
    exempted aquifer.
  • 10,000 mg/l is FAR TOO SALINE for drinking water
    supplies in this Commonwealth

37
Section 78.83a.(a)(1) Methodology for
Determining Deepest Fresh Groundwater
  • Numerical considerations elsewhere
  • Texas 3000 mg/l TDS
  • Oklahoma 10,000 mg/l TDS
  • Illinois 10,000 mg/l TDS
  • New York 1,000 mg/l TDS
  • Alberta 4,000 mg/l TDS to a depth not to exceed
    600 meters

38
Section 78.83a.(a)(1) Methodology for
Determining Deepest Fresh Groundwater
  • Numerical considerations (31 states surveyed)

GWPC (2009)
39
Section 78.83a.(a)(1) Methodology for
Determining Deepest Fresh Groundwater
  • Numerical considerations (15 states with
    quantitative definition)

GWPC (2009)
40
Section 78.83a.(a)(1) Methodology for
Determining Deepest Fresh Groundwater
  • Techniques for defining base of deepest fresh
    groundwater aquifer
  • Estimating fracture zone yield and measuring
    specific conductance using a calibrated meter
    during drilling
  • Standard water well geophysical logging of
    tophole specific conductance critical, but
    other logs may help corroborate water-bearing
    zones
  • More sophisticated geophysical logging of
    tophole per EPA UIC recommendations (SP log or
    resistivity/porosity log)
  • Installation of monitoring wells at well pad and
    groundwater testing
  • Information from offset wells including water
    well testing, geophysical log data, and surface
    casing set depths considering water well
    offsets alone will typically not be enough

Williams (2010)
41
78.83b. Casing and Cementing Lost Circulation
New Section
  • If cement used to permanently cement the surface
    or coal protective casing cannot be circulated to
    the surface due to lost circulation, the operator
    shall determine the top of cement, notify the
    Department and meet one of the following
  • Run additional string 50 deeper than where
    circulation was lost, cement back to lost
    circulation string casing seat, vent the annulus,
    meet pressure requirements of 78.73(c)
  • Run production casing and set on packer, vent the
    annulus
  • Run production casing to formation being
    produced, cement to surface
  • Run intermediate and production casing and cement
    both strings to surface
  • May also emplace supplemental cement in addition
    to the above

42
78.83b. Casing and Cementing Lost Circulation
New Section- continued
  • Policy cement returns to surface followed by
    cement drop may be considered to be permanently
    cemented if the DEP inspector determines an
    adequate amount of surface casing cement was
    placed above the seat.
  • Top of cement determination must be made and
    notification given to the DEP inspector for
    evaluation of casing cement adequacy and
    subsequent approval for remedial casing options.
    Must be done prior to continuation of drilling
    (e.g. no TOC determination after well
    drilled/completed to TD).
  • In addition to remedial casing options, the
    minimum amount of surface casing cement above
    seat and corresponding maximum amount of
    uncemented surface casing will be made on a
    case-by-case basis by DEP. In certain cases, the
    well may need to be plugged and abandoned if only
    a minimal amount of cement exists above the
    surface casing seat (a catastrophic loss of
    cement).
  • DEP may require remedial cementing from surface
    and/or pressure-testing of the casing string to
    determine integrity of the well and ensure
    protection of the surface casing seat.

43
78.83c. Intermediate and Production Casing New
Section
  • Prior to cementing intermediate and production
    casing, the borehole, mud, and cement must be
    conditioned to ensure an adequate cement bond
    between the casing and the formation
  • If a well is to be equipped with intermediate
    casing, centralizers must be used and the casing
    must be cemented to the surface by the
    displacement method gas may be produced off the
    intermediate casing if a shoe test demonstrates
    that all gas will be contained within the well
    and a relief valve is installed at the surface
    that is set at less than the shoe test pressure
    (this pressure must be recorded in the completion
    report)
  • Except as provided by 78.83, each well must be
    equipped with production casing centralizers
    must be used the production string may be set on
    a packer or cemented in place annular space must
    be cemented to a point at least 500 ft. above the
    TVD or at least 200 ft. above the uppermost
    perforations, whichever is greater.

44
78.84. Casing Standards Original Language
  • Casing must withstand the effects of tension, and
    prevent burst and collapse during its
    installation, cementing, and subsequent drilling
    and producing operations
  • Casing must be equipped with appropriate
    equipment to center the casing through the hole
    in fresh groundwater zones
  • Coal protective casing must have a minimum wall
    thickness of 0.23 inches

45
78.84. Casing Standards New Language
  • All casing must be a string of new pipe with a
    pressure rating at least 20 greater than the
    anticipated maximum pressure
  • Used casing may be approved but must be pressure
    tested after cementing and before continuation of
    drilling a passing pressure test is holding the
    maximum anticipated pressure for 30 minutes with
    no more than a 10 change in pressure. Pressure
    testing should be done before significant gel
    strength has developed in the cement. API RP65
    Part 2
  • New or used plain end casing that is welded must
    be pressure tested and hold the maximum
    anticipated pressure for 30 minutes with no more
    than a 10 change in pressure
  • Welded casing must be welded using at least three
    passes with the joint cleaned between each pass
  • Welder must be trained and certified in the
    applicable API, ASME, AWS or equivalent standard
    for welding casing and pipe or an equivalent
    training and certification program a person with
    10 or more years of experience welding casing
    does not need to be certified Note that the
    certification requirements do not kick in until
    August 5, 2011

46
78.85. Cement Standards Original Requirements
  • Cement must resist degradation by chemical and
    physical conditions in the well
  • Minimum compressive strength of 350 psi in
    accordance with API spec 10 cement must set for
    a minimum period of eight (8) hours prior to the
    resumption of actual drilling
  • Operator may request approval from DEP to reduce
    the cement setting time when special cement or
    additives are used

47
Chapter 78.85 New Cement Standards
  • Revised cement standards
  • Cement must protect casing from corrosion and
    geochemical, lithologic and physical conditions
    of the surrounding wellbore
  • Gas-block additives and low fluid-loss slurries
    in areas of known shallow gas-producing zones are
    required
  • Zone of critical cement around surface casing
    seat
  • True eight-hour WOC (wait on cement) before
    casing may be disturbed
  • One-day notification to DEP prior to cementing of
    surface casing
  • Cement job log must be prepared and available at
    the well site during drilling operations and
    maintained for at least five years

48
Chapter 78.85 New Cement Standards
  • Zone of Critical Cement
  • Applies to bottom 300 ft. of surface casing
    cement, or entire cemented string if the surface
    casing string is less than 300 ft
  • Cement must achieve a 72-hour compressive
    strength of 1200 psi
  • Cement must achieve a free-water separation of no
    more than 6 milliliters of water per 250
    milliliters of cement

49
Chapter 78.85 New Cement Standards
  • Eight-hour WOC (wait on cement) casing may be
    not be disturbed by
  • Releasing pressure on the cement head if check
    valves on float shoe are secure, the pressure may
    be released at a continuous, gradual rate after
    four hours
  • Nippling up on or in conjunction to the casing
  • Slacking off by the rig supporting the casing in
    the cement sheath
  • Running drill pipe or other mechanical devices
    into or out of the wellbore with the exception of
    a wireline used to determine the top of cement

50
Chapter 78.85 New Cement Standards
  • Cement job log required components
  • Mix water temperature and pH
  • Type of cement with listing and quantity of
    additives
  • Volume, yield, and density in ppg of the cement
  • Amount of cement returned to the surface
  • Cementing procedural information including a
    description of the pumping rates in bbl/min,
    pressure in psi, time in min, and the sequence of
    events during the cementing operations
  • Logs must be available for all cement jobs done
    after 2/5/2011.

51
Section 78.88 Mechanical Integrity of Operating
Wells
  • Quarterly monitoring program will begin first
    quarter after the Department develops a standard
    form for collecting mechanical integrity data
  • Key monitoring/testing provisions
  • Pressure monitoring associated with production
    casing
  • Pressure monitoring in annular space associated
    with production casing
  • Pressure monitoring at relevant casing seat
  • Checking well fluid level in production casing
  • Corrosion and equipment deterioration survey
  • Monitoring for leaking gas
  • Clear methodology for addressing over-pressured
    wells
  • Flexibility for Department to require additional
    testing
  • Report detailing results of quarterly inspections
    must be submitted to Department annually by
    January 31 of year following inspections

52
Operating Wells 78.88 Mechanical Integrity of
Operating Wells
  • For wells not in compliance, the operator must
    immediately notify DEP and take corrective action
    to mitigate the excess pressure on the surface
    casing seat, coal protective casing seat, or
    intermediate casing seat when the intermediate
    casing seat is used in conjunction with the
    surface casing seat to isolate fresh groundwater
  • Corrective action occurs in the following
    hierarchy
  • Operator must reduce the shut-in or producing
    back pressure to achieve compliance with 78.73(c)
  • Operator must retrofit the well by installing
    production casing to reduce pressure on the
    casing seat to achieve compliance with 78.73(c)
    the annular space surrounding the production
    casing must be open to the atmosphere production
    casing must either be cemented in place or
    installed on a permanent packer
  • Operator must notify DEP 7 days prior to
    initiating corrective action

53
Section 78.88 Mechanical Integrity of Operating
Wells
  • Potential well problems

54
Section 78.88 Mechanical Integrity of Operating
Wells
  • Potential well problems overpressuring

Harrison (1985)
55
Section 78.88 Mechanical Integrity of Operating
Wells
  • Potential well problems overpressuring
    (continued)

Harrison (1985)
56
Section 78.88 Mechanical Integrity of Operating
Wells
  • Potential well problems overpressuring
    (continued)

Harrison (1985)
57
Section 78.88 Mechanical Integrity of Operating
Wells
  • Potential well problems cement failures and
    inadequate casing/tubing

58
Section 78.88 Mechanical Integrity of Operating
Wells
  • Some notable items
  • Operators will not be required to retrofit older
    wells for pressure monitoring
  • Overpressured conditions or problems noted
    during well corrosion/equipment deterioration
    survey must be reported immediately
  • 7-day notification for wells that will be
    retrofitted with production casing

59
Section 78.88 Mechanical Integrity of Operating
Wells
  • Some notable items (continued)
  • Water protection depth will apply in older wells
    where fluid levels can be determined
  • Pressure monitoring locations will vary as a
    function of well construction

60
Section 78.88 Mechanical Integrity of Operating
Wells
  • Department projects underway or being considered
    to assist the industry
  • Development of comprehensive technical
    guidance/instructions to accompany form to ensure
    consistency and ease of implementation
  • Development of tracking system for problems
    noted to help identify what well maintenance
    procedures are critical during various points
    throughout operational history

M.I.C.S.(2011)
61
78.89. Stray Gas Mitigation Response
  • Establishes protocol for operator, DEP, and local
    emergency response agencies to determine the
    nature of a gas migration incident, assess the
    potential for hazards to public health and
    safety, and mitigate any hazard posed by the
    release of natural gas
  • Operator, in conjunction with the Department and
    local emergency response agencies, must take
    measures necessary to ensure public health and
    safety

62
Section 78.89 Gas Migration Response
  • Stray gas migration incidents continue to
    represent one of the most significant problems
    associated with oil and gas development in the
    Commonwealth
  • Previous discussion on well integrity highlighted
    some problems that result in stray gas migration
    incidents
  • Other contributing factor in Pennsylvania is the
    number of legacy/abandoned wells that were never
    properly plugged and whose locations remain
    unknown
  • Stray gas migration associated with Marcellus
    Shale development has been geographically
    isolated

63
Section 78.89 Gas Migration Response
  • Physical properties of methane
  • The simplest of all paraffin hydrocarbon gas
  • Flammable, colorless, and odorless
  • Specific gravity 0.555
  • Explosive range 5-15
  • Maximum solubility in water 26-32 mg/l at
    standard temperature and pressure, but higher at
    depth due to pressure regime

Baldassare (2009)
64
Section 78.89 Gas Migration Response
  • Factors influencing stray gas migration
  • Changes in barometric pressure
  • Soil and bedrock porosity/permeability
  • Pore water
  • Temperature contrasts
  • Other meteorological conditions including
    precipitation (rain vs. snow) and ground cover
    (layer of snow or frozen ground)

Figure courtesy of John Harper, PA Topographic
and Geologic Survey
65
Section 78.89 Gas Migration Response
  • Types of gas and isotopic signatures (Baldassare,
    2009)
  • Subsurface microbial gas (deep- sea sediments
    and drift gas)
  • Near-surface microbial gas (marsh gas and
    landfill gas)
  • Thermogenic gas (natural gas and coalbed gas)

Baldassare (2009)
66
Section 78.89 Gas Migration Response
  • Locations total number of stray gas cases since
    1987 compared to all permitted drilling activity

67
Section 78.89 Gas Migration Response
  • Location of Marcellus Shale stray gas cases
    since 2008 compared to Marcellus Shale drilling
    activity between 2008 and 2010

68
Section 78.89 Gas Migration Response
  • Recent trends in stray gas incidents Marcellus
    Shale versus non-Marcellus Shale wells

69
Section 78.89 Gas Migration Response
  • Key components of stray gas regulations
  • Operators notified about a potential stray gas
    migration incident must immediately conduct an
    investigation to determine nature of incident,
    assess potential hazards, and mitigate hazards
    as needed
  • Response actions are tiered based on the
    severity of the incident
  • Investigation closure dependent upon Department
    approval

70
Section 78.89 Gas Migration Response
  • A three-tiered approach
  • Category 1 (Immediate Threat) detectable
    concentrations equal to or greater than 10 of
    the lower explosive limit (LEL) or combustible
    gas in a building or structure(s), or otherwise
    deemed Category 1 by the Department.
  • Category 2 (Potential Threat) detectable
    concentrations less than 10 of the LEL of
    combustible gas in a building or structure(s),
    and/or combustible gas greater than 50 of the
    LEL in the headspace of a water well, and/or
    visual or audible evidence of stray gas bubbling
    through a water well column or surface body,
    and/or detectable concentrations of stray gas in
    the soils, and/or concentrations of dissolved
    methane in water at or above 25 of the lower
    solubility limit for methane (7 mg/l).
  • Category 3 (No Apparent Threat) none of the
    above conditions were met. If conditions
    indicate methane in groundwater at concentrations
    above 0.5 mg/l, but below 7 mg/l, continued
    monitoring is necessary to ensure that
    concentrations do not trend to a Category 2
    potential threat.

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Section 78.89 Gas Migration Response
  • Department projects underway or being considered
    to assist the industry
  • Development of stray gas migration technical
    guidance document to compliment new regulations
  • NCRO Stray Gas Prevention Program
  • Series of joint technical guidance and public
    outreach documents with Emergency Response staff

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Plugging 78.91 78.98
  • Second attempt to remove production casing after
    cutting, ripping, shooting or other method
    approved by the Department.
  • Cement plug now to be placed across oil or
    gas-bearing strata (rather than gel).
  • Next regulatory package will significantly revise
    plugging regulations.

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Chapter 78. Oil and Gas Wells
  • Subchapter E Well Reporting

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Chapter 78. Oil and Gas Wells
  • Subchapter E Well Reporting Revisions
  • 78.121. Production reporting Incorporates the
    requirements of Act 15 of 2010 which mandates
    semi-annual reporting of production of Marcellus
    Shale wells (8/15 2/15) Non-Marcellus wells
    report annually (2/15) Information is posted on
    DEPs website
  • 78.122. Well record and completion report
    Completion report to include descriptive list of
    chemical additives used in the stimulation fluid
    the percent by volume of those additives a list
    of hazardous chemicals used in the stimulation
    fluid (MSDS/CAS ) the percent by volume of
    those hazardous chemicals the total volume of
    water used a list of water sources used pursuant
    to an approved water management plan the total
    volume of recycled water used and the pump rate
    and pressure used in completing the well
  • Operator must designate separate sheet as
    confidential or a trade secret DEP will prevent
    disclosure of confidential information to the
    extent provided by the Right-To-Know Law
  • Well record adds certification by operator that
    well has been constructed in accordance with this
    Subchapter and any permit conditions imposed by
    DEP

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Thank youdaenglish_at_state.pa.us(717) 772-2199
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