Observations on a Montana Water Quality Proposal Page iii

TABLE OF CONTENTS 

Executive Summary............................................................................................................... v 

Introduction .......................................................................................................................... 1 

Purpose of This Report .......................................................................................................... 1 

1. CBNG Produced Water: Undesirable Pollutant or Valued Resource? ............................ 2 

2. Proper Consideration of CWA Authority and Guidance Relating to 

Technology-Based Discharge Limits............................................................................... 4 

 A. Background................................................................................................................ 4 

 B. Equivalence of Federal and Montana Regulations .................................................. 5 

 C. Technology-Based Limits........................................................................................... 7 

 D. What Is BAT and How Is It Expressed?..................................................................... 9 

 E. The Distinction between BAT and BPJ...................................................................... 10 

 F. The Proposal’s Version of Technology-Based Limits................................................ 10 

 G. Comparison of the Proposal to EPA Technology-Based Limits Procedures ............ 13 

3. Does the Proposal Preclude the Use of Other Innovative 

or Beneficial Technologies? ............................................................................................ 18 

4. Are the Proposed Discharge Standards Stricter Than Needed 

to Meet Montana Water Quality Standards?.................................................................... 18 

5. Summary of Key Observations........................................................................................ 20 

Appendix A – Permit Limit Guidelines Used by Maryland Department 

of Environment in Late 1980s................................................................................................ 21 

TABLES 

1 Steps and time line for Montana DEQ review of waiver application.............................. 15 

2 Comparison of CBNG produced water management technologies 

in relation to the CWA factors for technology-based limits............................................ 17 

3 Comparison of proposed effluent limits to water quality standards ................................ 19 
Observations on a Montana Water Quality Proposal Page iv

FIGURES 

1 Normal Distribution......................................................................................................... 25 

2 Lognormal Distribution ................................................................................................... 25 
Observations on a Montana Water Quality Proposal Page v

Executive Summary

During the fall of 2005, the Montana Board of Environmental Review (BER) announced 

proposed changes to the Montana water quality regulations. The proposal, which was based on a 

petition from the Northern Plains Resource Council, was directed toward discharges of water 

from coal bed natural gas (CBNG) production. The proposed regulations, if adopted in their 

current form, are likely to substantially reduce the amount of CBNG production in Montana. 

The impact also extends to Wyoming CBNG production through much greater restrictions on 

water quality that must be met at the interstate border. 

The U.S. Department of Energy (DOE) reviewed the BER proposal and believed that the 

proposal could restrict CBNG production in Montana and Wyoming. To aid in the review of the 

proposal, DOE asked two of its national laboratories — Argonne National Laboratory and 

Sandia National Laboratories — to prepare written evaluations on various aspects of the 

proposal. This report contains Argonne’s review and observations on the proposal. 

The proposal inconsistently characterizes the value of CBNG produced water. In some places, 

the proposal refers to it as “wastewater” and emphasizes that some of its constituents are 

“hazardous parameters.” In other places, the proposal acknowledges the water’s value in both 

quantity and quality and implements measures to ensure that the water is available for future 

beneficial use. This inconsistency is misleading. 

The Clean Water Act (CWA) allows the U.S. Environmental Protection Agency (EPA) to 

delegate National Pollutant Discharge Elimination System (NPDES) authority to states. 

Montana applied for and received the authority to administer the federal NPDES program. To 

administer the NPDES program, the state uses regulations that either adopt EPA’s regulations 

directly by reference or it has promulgated similar and consistent state regulations. The proposal 

does not follow the CWA guidelines for establishing technology-based limits. The most notable 

excursion from the guidelines is the proposal’s attempt to force the use of just one or two 

specific technologies. The BER is within its rights to require zero discharge, assuming that it can 

show that appropriate water management alternatives are available and affordable. However, the 

BER may not specify the type of technology that must be used to achieve zero discharge. In 

addition to the procedural issues raised by the proposal, this strategy effectively blocks the 

opportunity for other beneficial and innovative technologies to be used. 

The proposal includes numerical technology-based effluent limits. They are very stringent, and 

no detailed rationale is provided to explain why they were selected. Traditional methods to 

evaluate best available technology economically achievable (BAT) and best professional 

judgment (BPJ) technology-based limits were not followed. BAT is not a specific technology 

but rather is the performance that can be produced by properly operated “BAT model 

technology.” BAT limits are not set at the level of performance of one or a few particularly 

well-operated treatment facilities on a good day or at the theoretical level of performance 

claimed by an equipment manufacturer. Rather they reflect the performance of multiple facilities 

using proper technology in actual industrial circumstances over a long period of time. Typically, 

statistical calculations are used to determine appropriate average and maximum limits. BPJ 

limits are expected to follow similar procedures to those that EPA uses to establish BAT. 
Observations on a Montana Water Quality Proposal Page vi

The proposal and the petition make various claims about the affordability of reinjection and 

treatment to achieve the proposed limit as they relate to the overall wellhead price of natural gas. 

Some of these cost estimates were derived from a 2003 draft EPA study that has never been 

released. Relying on data from an unpublished report is not a sound basis for setting new stricter 

regulations. Further, the BER and the petitioners appear to have overlooked the fact that the 

draft EPA study evaluates the cost of achieving a different, and much less stringent, set of 

discharge standards from those required by the proposal. The cost for treating water or 

wastewater increases as the target treatment standards are made more stringent. Thus the costs 

estimated by the draft EPA report underestimates the actual costs that would be associated with 

meeting the proposal’s strict limits, and therefore are not fully relevant as rationale for 

supporting new limits. 

The proposed effluent limits are much stricter than necessary to meet water quality standards in 

Montana water bodies. If the proposal had properly demonstrated that these strict limits 

represented BAT, they could be employed. The proposal does not make such a demonstration, 

and therefore the limits appear to be unnecessarily stringent. For several of the parameters in the 

proposed effluent limits (calcium, magnesium, sodium, bicarbonate, and total dissolved solids or 

TDS), there are no water quality standards. For the other parameters that do have water quality 

standards, the proposed effluent limits are far stricter than water quality standards in all cases. In 

other words, dischargers must treat to levels significantly cleaner than the receiving waters. 

The proposal contains several apparent logical inconsistencies. First, the proposal calls for 

“minimum technology-based effluent limitations” [emphasis added]. The proposed numerical 

limits are most likely intended to be maximum limits, not minimum limits. Second, for several 

parameters, the average concentrations must be kept within a range (e.g., the calcium average 

concentration must be between 0.1 mg/L and 0.2 mg/L. There is no apparent reason to set a 

“minimum” standard as a range, nor is there any reason to limit concentrations to a range. Under 

this provision, a calcium average of either 0.08 mg/L or 0.3 mg/L is out of compliance. Third, 

the proposed limits create an internally inconsistent situation. The sodium adsorption ratio 

(SAR) is calculated by a formula that combines sodium, calcium, and magnesium. If the 

proposed average effluent limits for each of these parameters are entered into the SAR equation, 

they result in SAR values of 2.5 to 5.3. The proposed SAR effluent limit is 0.5 maximum. Thus 

it appears that discharges complying with the three component parts of the SAR equation will 

still be in violation of the SAR limit. 
Observations on a Montana Water Quality Proposal Page 1

Introduction 

In May 2005, a group of petitioners led by the Northern Plains Resource Council (NPRC) 

submitted a petition to revise water quality requirements to the Montana Board of Environmental 

Review (BER). Under Montana law, the BER had to consider the petition and either reject it or 

propose it as a new regulation. In September 2005, the BER announced proposed changes to the 

Montana water quality regulations. The proposal, which included almost the exact language 

found in the petition, was directed toward discharges of water from coal bed natural gas (CBNG) 

production. The key elements of the proposal included: 

1. No discharges of CBNG water are allowed to Montana surface waters unless operators 

can demonstrate that injection to aquifers with the potential for later recovery of the water 

is not feasible. 

2. When operators can demonstrate the injection is not feasible, the CBNG water to be 

discharged must meet very strict technology-based limits for multiple parameters. 

3. The Montana water quality standards for the sodium adsorption ratio (SAR) and electrical 

conductivity (EC) would be evaluated using the 7Q10 flow (lowest 7-consecutive-day 

flow in a 10-year period) rather than a monthly flow that is currently used. 

4. SAR and EC would be reclassified as “harmful parameters,” thereby greatly restricting 

the ability for CBNG discharges to be allowed under Montana’s nondegradation 

regulations. 

The proposed regulations, if adopted in their current form, are likely to substantially reduce the 

amount of CBNG production in Montana. The impact also extends to Wyoming CBNG 

production through much greater restrictions on water quality that must be met at the interstate 

border. 

Purpose of This Report 

One of the U.S. Department of Energy’s (DOE’s) missions is to ensure an abundant supply of 

affordable energy for the nation. One way in which DOE supports that mission is to evaluate 

proposed federal and state regulatory actions that would restrict or impede energy production to 

assess whether the environmental or other benefits of those actions are commensurate with the 

energy impacts. DOE’s National Energy Technology Laboratory (NETL) reviewed the BER 

proposal and believed that the proposal could restrict CBNG production in Montana and 

Wyoming. To aid in the review of the proposal, NETL asked two other DOE national 

laboratories — Argonne National Laboratory (Argonne) and Sandia National Laboratories 

(Sandia) — to prepare written evaluations on various aspects of the proposal. Argonne focused 

on regulatory and policy issues and their interrelationships with technology, and Sandia focused 

on water treatment and engineering and hydrologic and geologic technical issues. 

This report represents Argonne’s review and observations. The main themes of these comments 

include: 
Observations on a Montana Water Quality Proposal Page 2

- Does the proposal consider CBNG produced water as an undesirable pollutant or as a 

valued resource? 

- Did the BER proposal adequately follow federal Clean Water Act (CWA) authority and 

guidance concerning technology-based effluent limits? 

- Does the proposal preclude the use of other innovative or beneficial technologies? 

- Are the proposed discharge standards stricter than needed to meet Montana water quality 

standards? 

The rationale included with the proposal for making the proposed changes is not very specific or 

detailed. The language in the proposal is taken nearly word-for-word from the petition, but the 

petition is longer and provides more details for the proposed actions. We therefore reviewed the 

petition as well, and much of the discussion in this report is based on statements and positions 

contained in the petition. 

1. CBNG Produced Water: Undesirable Pollutant or Valued Resource? 

The proposal is not consistent in how it views CBNG produced water. It characterizes the water 

in different ways to support different portions of the proposed revisions. It suggests that CBNG 

is wastewater and contains harmful properties when attempting to make the water quality 

standards and nondegradation requirements more stringent. Yet when the proposal pushes for 

reinjection of the CBNG produced water whenever practicable, it treats the water as a valuable 

commodity for current and future purposes. 

Some of the revisions included in the proposal are geared toward emphasizing that CBNG 

produced water is an undesirable substance with deleterious properties. Two examples are 

shown below: 

17.30.670 NUMERIC STANDARDS FOR ELECTRICAL CONDUCTIVITY (EC) AND 

SODIUM ADSORPTION RATIO (SAR) (1) through (5) remain the same. 

(6) Changes in existing surface or ground water quality with respect to EC and SAR are 

nonsignificant according to the criteria in 75-5-301(5)(c), MCA, provided that the 

change will not have a measurable effect on any existing or anticipated use or cause 

measurable changes in aquatic life or ecological integrity. EC and SAR are harmful 

parameters for the purposes of the Montana Water Quality Act, Title 75, chapter 5, MCA. 

and 

17.30.1202 DEFINITIONS For the purposes of this subchapter, the following definitions 

apply: 
Observations on a Montana Water Quality Proposal Page 3

 (8) "Methane wastewater" means water produced from coal bed methane extraction 

during exploration or development activities. 

In the first example, the term “harmful parameter” leads to stricter consideration under the 

Montana nondegradation regulations, but more directly, a “harmful parameter” sounds much 

more dangerous or sinister than a parameter without the “harmful” designator. The parameters 

EC and SAR are not inherently harmful. EC is a measure of the level of dissolved materials or 

salinity in a water sample. It does not measure a specific or single chemical substance that could 

be construed as harmful. SAR is calculated by a ratio of sodium, calcium, and magnesium. The 

Montana Numeric Water Quality Standards, as listed in Circular WQB-7, do not contain any 

standards for sodium, calcium, or magnesium. None of the three individual chemicals are 

individually listed as harmful parameters. 

Neither EC nor SAR is harmful under all or even most situations. It is impossible to make a 

determination of risk or harm without establishing a specific context. Both parameters, like most 

other water quality parameters, have little or no effect at some level, but begin to pose a risk to 

aquatic life, humans, plants, and/or soils at a higher level. In other words, EC and SAR can be 

present at safe levels, intermediate levels, and undesirable levels. The magnitude of specific 

values in relation to the threshold between low risk and high risk is the key in determining 

whether the parameters are harmful or not. 

In the second example, the term “wastewater” carries a different connotation than “produced 

water” or “unaltered ground water from coal bed methane development.” The latter term is used 

to describe the substance in question in the existing BER regulations. Clearly, the petition and 

likewise the proposal are trying to send a message that the water brought to the surface during 

CBNG production is a waste stream. 

The previous examples indicate that the proposal seems to treat the CBNG produced water as an 

undesirable substance that is “wastewater” and contains “harmful parameters.” However, the 

proposal is not consistent in that characterization. The following excerpt from the proposal 

suggests that the water withdrawn during CBNG production represents a beneficial material that 

should not be discharged and lost from the state’s water resources. 

REASON: Why Minimum Technology-Based Controls and Treatment Requirements are 

Necessary 

3. The reason for requiring reinjection of all coal bed methane wastewater into suitable 

geologic formations (unless re-injection is technically unfeasible) is to maximize the 

volume of water that will be put back into aquifers from which it was taken. This 

requirement will alleviate the draining of aquifers and the drying up of wells and springs 

that are used by petitioners. 

4. The reason that water must be reinjected into "suitable geologic formations" 

(i.e., aquifers with water of similar quality to coal bed methane wastewater) is to ensure 

that the water resource is available for beneficial use in the future. For this reason, 

reinjection into deep geologic formations that are considered Class II wells under the 

Safe Drinking Water Act's Underground Injection Control (UIC) program is not allowed 
Observations on a Montana Water Quality Proposal Page 4

under the rules because the water quality in those formations typically will not qualify as 

being "suitable geologic formations." 

The rationale expressed in BER’s Item 3 is that the CBNG produced water has value for its 

volume. The proposal suggests that, wherever technically feasible, the water should be 

reinjected into suitable geologic formations. The rationale also suggests that wells and springs 

currently in use by petitioners would be affected by withdrawing and discharging the CBNG 

produced water from the coal seams. This particular point is not documented by specific 

examples; in fact, most of the potable and irrigation water supplies in the region are taken from 

depths shallower than the depths at which the coal seams are located. 

The rationale expressed in Item 4 goes even further, suggesting that the CBNG produced water 

has value as a future beneficial resource. Although not specifically stated in Item 4, if the water 

is anticipated to have a future beneficial use, its current quality must be clean enough that it 

could be used either “as is” or after treatment with some readily available and affordable 

technology. To further emphasize this perspective, New Rule IX of the proposal permits some 

of the CBNG water to be reused for livestock watering. 

2. Proper Consideration of CWA Authority and Guidance Relating to Technology-Based 

Discharge Limits 

The proposal does not follow the CWA guidelines for establishing technology-based limits. The 

most notable excursion from the guidelines is the proposal’s attempt to force the use of just one 

or two specific technologies. The BER is within its rights to require zero discharge, assuming 

that it can show that appropriate water management alternatives are available and affordable. 

However, the BER may not specify the type of technology that must be used to achieve zero 

discharge. The proposal includes numerical technology-based effluent limits. They are very 

stringent, and no detailed rationale is provided to explain why they were selected. Traditional 

methods to evaluate best available technology economically achievable (BAT) and best 

professional judgment (BPJ) technology-based limits were not followed. 

The following sections describe the federal legal requirements concerning technology-based 

limits, the relationship between federal and Montana laws and regulations, the language used in 

the proposal to establish technology-based limits, and how the proposal differs from the federal 

requirements.

A. Background 

The CWA established the framework for regulating wastewater discharges through the National 

Pollutant Discharge Elimination System (NPDES) program. The U.S. Environmental Protection 

Agency (EPA) was given authority to establish regulations for the program using the general 

guidelines in the CWA. States can be delegated as authorities to administer the NPDES program 

if they can demonstrate that they have adequate state laws and regulations to equal or exceed the 

NPDES requirements. 

Some of the features of the CWA and the NPDES program that are relevant to the BER proposal 

include: 
Observations on a Montana Water Quality Proposal Page 5

- All point source discharges of wastewater made to surface water bodies must be 

authorized by NPDES permits. Discharges made to other places (e.g., land surface via 

irrigation, underground injection, evaporation) are not subject to federal NPDES permits. 

Underground injection activities are regulated under a separate federal program (the 

Underground Injection Control, or UIC, program) that can also be delegated to able and 

willing states. Some states have developed separate state groundwater discharge permit 

programs. 

- Irrigation return flows to surface water bodies are exempted from needing NPDES 

permits. Nevertheless, they can have a water quality impact and may be controlled 

through water quality programs other than through NPDES where necessary. Irrigation 

return flows are made to some of the rivers in the region. 

- Permits must contain numeric limits for parameters of concern. The limits are calculated 

using both a technology basis and a water quality basis; whichever basis results in stricter 

limits for each pollutant is used in the permit. 

- The CWA directs EPA to establish effluent limitations guidelines (ELGs) for most major 

industrial sectors. Where these are available, they are used as the national minimum 

technology-based limits. Although EPA has developed ELGs for the oil and gas industry 

and the coal mining industry, it has never developed ELGs specific to discharges of 

CBNG produced water. 

- For industries or specific waste streams for which ELGs have not been developed by 

EPA, the permit writer is expected to establish appropriate technology-based limits by 

using BPJ. The NPDES regulations describe the types of features that must be 

considered in a BPJ determination. The BER proposal uses a BPJ process to establish a 

“state-equivalent ELG.” 

Additional detail on several of these topics is provided in the following sections. 

B. Equivalence of Federal and Montana Regulations 

Federal NPDES provisions and requirements are identical to those in Montana for most or all of 

the relevant sections. Montana applied for and received authority to administer the NPDES 

program in its state waters. The Montana Water Quality Regulations, Subchapter 13, cover the 

Montana Pollutant Discharge Elimination System (MPDES permits). Section 17.30.1303 

(incorporations by reference) of those regulations describes the strong equivalence between the 

federal NPDES and the state MPDES regulations. Many of the regulations are incorporated 

word-for-word through reference. 
Observations on a Montana Water Quality Proposal Page 6

(1) In accordance with the federal Clean Water Act, this subchapter of Title 17, 

chapter 30, establishes a permit system (MPDES) which is essentially the equivalent of 

the federal permit system (NPDES) administered by the EPA. 

(2) In view of the federal Clean Water Act's requirement of equivalence with the federal 

permit system, and in order to simplify the rulemaking process and make the rules less 

cumbersome, the department has relied heavily upon incorporation and adoption by 

reference of federal requirements as set forth in Title 40 of the Code of Federal 

Regulations (CFR) and in the federal Clean Water Act, 33 USC 1251, et seq. 

(3) Where the department has adopted a federal regulation or statute by reference, the 

following shall apply: 

(a) References in the federal regulations to "administrator", "regional 

administrator", or "US environmental protection agency", or the like, should be 

read to mean "department". 

(b) Where the department incorporates by reference a subpart of a federal 

regulation, both the subpart and its constituent sections and subsections are also 

incorporated by reference. 

(4) All of the incorporations by reference of federal agency regulations listed in the table 

in (7) of this rule shall refer to federal agency regulations as they have been codified in 

the July 1, 1991, edition of Title 33 and 40 of the Code of Federal Regulations (CFR). 

Section 17.30.1344 (establishing limitations, standards, and other permit conditions) lists specific 

EPA regulations relevant to permit limits that are incorporated by reference. 

(1) In addition to the conditions established under ARM 17.30.1342, 17.30.1343, 

17.30.1346, 17.30.1350, and 17.30.1351, each MPDES permit must include conditions 

meeting the requirements stated in 40 CFR 122.43, 122.44, 124.56 and 124.57 (July 1, 

1991). 

(2) The board hereby adopts and incorporates herein by reference (see ARM 17.30.1303 

for complete information about all materials incorporated by reference): 

(a) 40 CFR 122.43 (July 1, 1991), which is a federal rule that establishes 

applicable permit conditions in general; 

(b) 40 CFR 122.44 (July 1, 1991), which is a federal agency rule setting forth 

additional permit conditions which may be applicable to a point source. Such 

conditions include technology-based and water-quality-based standards, toxic 

and pretreatment standards, reopener clause, reporting and monitoring 

requirements, permit duration and reissuance, test methods, best management 

practices, conditions concerning sewage sludge, privately owned treatment 

works, and conditions imposed in EPA grants to POTW's; 

(c) 40 CFR 124.56 (July 1, 1991), which describes requirements for fact sheets; 

(d) 40 CFR 124.57 (July 1, 1991), which describes the public notice that must be 

provided for draft permits; 

(e) 40 CFR chapter 1, subchapter N, (July 1, 1991), which sets forth federal 

effluent limitations and standards and new source performance standards; 

(f) 40 CFR Part 125 (July 1, 1991), which states standards and criteria for the 

national point discharge elimination system; 
Observations on a Montana Water Quality Proposal Page 7

(12) The board hereby adopts and incorporates herein by reference (see ARM 17.30.1303 

for complete information about all materials incorporated by reference): 

(a) 40 CFR 122.44(j)(2), which is a federal agency rule setting forth a 

requirement for the submittal by a publicly owned treatment work (POTW) of a 

local pretreatment program; 

(b) 40 CFR 122.45(b)(2)(ii)(A), which is a federal agency rule setting forth the 

availability of alternate permit limitations, standards, or prohibitions based on 

varying production levels; 

(c) 40 CFR 136, which is a series of federal agency rules setting forth guidelines 

for testing procedures for the analysis of pollutants; 

(d) 40 CFR 125.3, which is a federal agency rule setting forth technology-based 

treatment requirements for point source dischargers; 

C. Technology-Based Limits 

Having shown the similarity between the federal and Montana laws and regulations regarding 

water quality and permitting, we now review the federal basis for requiring and establishing 

technology-based limits. The first citation of importance is CWA Section 301 (b)(2)(A): 

(2)(A) for pollutants identified in subparagraphs (C), (D), and (F) of this paragraph,1

effluent limitations for categories and classes of point sources, other than publicly owned 

treatment works, which (i) shall require application of the best available technology 

economically achievable for such category or class... 

Best available technology economically achievable is often abbreviated as BAT; consequently, the 

“economically achievable” modifier may be overlooked. It is important to understand that EPA 

must select as the basis for BAT a technology that is already in use in a particular industry 

(or sometimes in a related industry) with a proven long-term track record of performance under the 

conditions associated with the type of discharge in question. Furthermore, the technology has to be 

affordable. 

EPA’s NPDES regulations include the mandate for technology-based limitations at Section 122.44 

(establishing limitations, standards, and other permit conditions): 

In addition to the conditions established under Sec. 122.43(a), each NPDES permit shall 

include conditions meeting the following requirements when applicable. 

(a)(1) Technology-based effluent limitations and standards based on: effluent limitations 

and standards promulgated under section 301 of the CWA, or new source performance 

standards promulgated under section 306 of CWA, or case-by-case effluent limitations 

determined under section 402(a)(1) of CWA, or a combination of the three, in 

accordance with Sec. 125.3 of this chapter. 

 

1 These are all pollutants other than biological oxygen demand, suspended solids, fecal coliform, and pH, which are 

classified as conventional pollutants and are subject to best conventional technology standards.
Observations on a Montana Water Quality Proposal Page 8

EPA explains the ways in which technology-based limits can be developed in 40 CFR 125.3 (c): 

(c) Methods of imposing technology-based treatment requirements in permits. 

Technology-based treatment requirements may be imposed through one of the following 

three methods: 

(1) Application of EPA-promulgated effluent limitations developed under section 304 of 

the Act to dischargers by category or subcategory.... 

(2) On a case-by-case basis under section 402(a)(1) of the Act, to the extent that EPApromulgated effluent limitations are inapplicable. The permit writer shall apply the 

appropriate factors listed in Sec. 125.3(d) and shall consider: 

(i) The appropriate technology for the category or class of point sources of which 

the applicant is a member, based upon all available information; and 

(ii) Any unique factors relating to the applicant. 

[Comment: These factors must be considered in all cases, regardless of whether the 

permit is being issued by EPA or an approved state.] 

(3) Through a combination of the methods in paragraphs (d) (1) and (2) of this section. 

The CWA does not specifically mention BPJ limits, but EPA uses the general provisions of 

CWA Section 402 (a)(1)(B) as its justification to require BPJ: 

(a)(1) Except as provided in sections 318 and 404 of this Act, the Administrator may, after 

opportunity for public hearing, issue a permit for the discharge of any pollutant, or 

combination of pollutants, notwithstanding section 301(a), upon condition that such 

discharge will meet either (A) all applicable requirements under sections 301, 302, 306, 

307, 308 and 403 of this Act, or (B) prior to the taking of necessary implementing actions 

relating to all such requirements, such conditions as the Administrator determines are 

necessary to carry out the provisions of this Act. 

CWA Section 304(b)(2)(B) outlines the factors that EPA must consider when developing BAT 

standards in formal ELGs: 

(B) specify factors to be taken into account in determining the best measures and practices 

available to comply with subsection (b)(2) of section 301 of this Act to be applicable to any 

point source (other than publicly owned treatment works) within such categories of classes.

Factors relating to the assessment of best available technology shall take into account the 

age of equipment and facilities involved, the process employed, the engineering aspects of 

the application of various types of control techniques, process changes, the cost of achieving 

such effluent reduction, non-water quality environmental impact (including energy 

requirements), and such other factors as the Administrator deems appropriate; 

These are echoed in EPA’s NPDES regulations at 40 CFR 125.3 (d), which explain the 

procedures that must be used by permit writers to establish BPJ limits: 

(d) In setting case-by-case limitations pursuant to Sec. 125.3(c), the permit writer must 

consider the following factors: 

 
Observations on a Montana Water Quality Proposal Page 9

(3) For BAT requirements: 

(i) The age of equipment and facilities involved; 

(ii) The process employed; 

(iii) The engineering aspects of the application of various types of control 

techniques; 

(iv) Process changes; 

(v) The cost of achieving such effluent reduction; and 

(vi) Non-water quality environmental impact (including energy requirements). 

D. What Is BAT and How Is It Expressed?

Section C describes what factors should be considered when establishing BAT requirements. It 

does not describe how BAT is actually expressed. This section provides some discussion on 

what BAT is and how it should be expressed. BAT limits are not set at the level of performance 

of one or a few particularly well-operated treatment facilities on a good day or at the theoretical 

level of performance claimed by an equipment manufacturer. Rather they reflect the 

performance of multiple facilities using proper technology in actual industrial circumstances 

over a long period of time. 

EPA develops ELGs by reviewing entire industrial categories and processes. EPA determines 

which technology or group of treatment processes most closely reflects the criteria for BAT. 

This technology is considered to be the “BAT model technology.” EPA then evaluates the longterm performance of that technology and uses a statistical method to estimate the level of 

performance that a well-operated facility employing the BAT model technology could achieve 

under actual industrial conditions. EPA recognizes that even well-operated facilities do not 

perform at exactly the same level day after day and seasonally. Thus the statistical method 

considers the degree of variability inherent in the production and treatment processes. The key 

point here is that BAT is the level of performance achievable by the model technology, not the 

specific treatment process, equipment, or steps that make up the model technology. In other 

words, BAT is expressed in terms of a performance (e.g., 20 mg/L) rather than as a process 

(e.g., reverse osmosis). 

EPA’s ELG program has collected data from thousands of different facilities for more than 

30 years. Within a particular industry, it may review data from a few to hundreds of facilities. 

Often the data from each facility contain long-term records over months to years. EPA has 

found that many sets of effluent data constitute a lognormal distribution. This looks much like 

the typical normal distribution (i.e., the bell curve — see Figure 1 in Appendix A), but the 

lognormal distribution has a much longer and flatter tail on the high end (see Figure 2 in 

Appendix A). This pattern is reflective of treatment systems that perform within reasonable 

boundaries most of the time but which experience occasional high values that cause the upper 

edge of the distribution to extend outward and flatten out. 

In many of its ELG evaluations, EPA has chosen to use the 95th percentile of the lognormal 

distribution as the average BAT limit and the 99th percentile as the maximum BAT limit. EPA 

has used some sophisticated statistics to describe key values of the lognormal distribution. An 

abbreviated version of this method is shown in Appendix A. This was developed by the lead 
Observations on a Montana Water Quality Proposal Page 10

author of this paper while managing the State of Maryland’s industrial NPDES permit program 

in 1987.2

 That procedure was used by Maryland NPDES permit writers from 1987 until at least 

1990, when he left the agency. 

E. The Distinction between BAT and BPJ 

Section D describes BAT. While the term BAT is often used generically to describe any sort of 

technology-based limits, BAT as an acronym for best available technology economically 

achievable is correctly used only in the context of EPA’s national ELGs. Any other effort to 

develop technology-based limits or standards, while comparable, should be called BPJ. A permit 

writer or, in this case, a state regulatory agency, can develop technology-based limits that reflect 

the criteria for BAT limits, but the limits themselves are correctly characterized as BPJ limits. 

This is not a critical issue for the BER proposal, but this section is added for additional 

clarification. 

F. The Proposal’s Version of Technology-Based Limits 

Having reviewed and described the federal requirements for establishing BAT and BPJ 

technology-based limits in Sections C, D, and E, we now examine how the proposal establishes 

technology-based limits. The treatment-based effluent limitations (i.e., technology-based limits) 

contained in the BER proposal are shown below. New Rule II requires zero discharge of CBNG 

produced water and directs that the water be reinjected to a suitable geologic formation. 

NEW RULE II ZERO DISCHARGE REQUIREMENT (1) Except as provided in [New 

Rules III through IX], point sources of methane wastewater shall achieve zero discharge 

of pollutants, which represents the minimum technology-based requirement. Zero 

discharge shall be accomplished by reinjection of methane wastewater into suitable 

geologic formations in the project area in compliance with all other applicable federal 

and state laws and regulations. 

New Rule III recognizes that there may not be suitable geologic formations available to receive 

some or all of the water to be reinjected. It allows operators to apply for a waiver under those 

circumstances. 

NEW RULE III WAIVER FROM ZERO DISCHARGE REQUIREMENT 

(1) The department may grant a waiver from the zero discharge requirement if the owner 

or operator of a point source discharge of coal bed methane wastewater demonstrates by 

clear and convincing evidence to the department through site specific studies that the 

requirement is not technically feasible because estimated wastewater production rates 

exceed the estimated cumulative reinjection rates of all suitable geologic formations in 

the project area. 

 

2 Lead author John Veil worked for the State of Maryland Department of Natural Resources, Office of 

Environmental Programs, and then the Department of the Environment from 1980 to 1990. During those 10 years, 

he wrote about 200 industrial NPDES permits. For most of that time, he managed Maryland’s industrial NPDES 

program and reviewed more than 1,000 NPDES permits. He wrote and revised some of Maryland’s water pollution 

control and NPDES regulations. From 1988 to 1990, he also managed Maryland’s UIC and oil control programs. 
Observations on a Montana Water Quality Proposal Page 11

(2) The department shall limit the waiver to the volume of methane wastewater for which 

the owner or operator shows that zero discharge is not technically feasible. The volume 

of methane wastewater for which the department grants a waiver from the zero discharge 

requirement shall be limited to the difference between estimated wastewater production 

rates and the estimated cumulative reinjection rates for all suitable geologic formation in 

the project area. 

(3) The department may limit the waiver to the initial phases of development when the 

volume of methane wastewater produced by wells is highest, which may make reinjection 

of all such water technically unfeasible. 

(4) The department may also grant a waiver from the zero discharge requirement if the 

EPA will not authorize the reinjection pursuant to a permit under the Safe Drinking 

Water Act (SDWA), 42 USC 300f to 300j-26(5). The operator shall attain zero discharge 

for the volume of methane wastewater for which the department does not grant a waiver. 

New Rule IV outlines the information that must be provided in the waiver application. 

NEW RULE IV INFORMATIONAL REQUIREMENTS FOR WAIVER DETERMINATION 

(1) An owner or operator requesting a waiver from the zero discharge requirement for 

coal bed methane wastewater shall submit an application to the department for the 

department to make a determination on whether to grant the waiver. 

(2) The application shall include, but is not limited to, the following: 

(a) a description and map of the coal bed methane project and project area 

showing the location of wells, pipelines, roads, compressors, and related 

infrastructure; 

(b) a description of the surface owners in the project area; 

(c) an estimate of pumping rates for coal bed methane wells in the target coal 

seams and an estimate of the volume of wastewater likely to be produced per well 

per year; 

(d) for each targeted coal seam, data showing areas characterized by high 

concentrations of vertical fractures where wastewater production wells may be 

higher; 

(e) an inventory and map of geologic formations, aquifers, and confining layers 

including significant fractures, fissures, and faults within the project area. The 

following information is required for each geologic formation and aquifer in the 

project area: 

(i) lateral extent, thickness, and depth. Maps and cross sections indicating the 

vertical and lateral limits of each formation; 

(ii) hydraulic properties including, but not limited to, transmissivity, storage 

coefficient, effective porosity, and hydraulic conductivity. The results of pump 

tests, analysis of core samples, and other geophysical studies; 

(iii) water quality characterization including the geochemical compatibility of the 

receiving aquifer minerals with methane wastewater; 

(f) an inventory and map of the locations of natural recharge in the project area 

and near the reinjection location; 

(g) an inventory of the wells, springs, and seeps in the project area including 

pumping rates for wells. A tabulation of data on all wells within the project area 
Observations on a Montana Water Quality Proposal Page 12

including a description of each well’s type, construction, date drilled, location, 

depth, record of plugging and/or completion, and any additional information 

known about the well; 

(h) the results of ground water modeling showing the relationship and hydrologic 

connectivity of the identified geologic formations and aquifers, the effects of 

fractures, fissures, faults, and other significant geologic features on ground water 

movement in the project area; 

(i) the results of pump tests of confining layers quantifying potential leakage 

through such layers; 

(j) a description of all potentially suitable geologic formations for reinjection 

within the project area. For each such suitable geologic formation, the operator 

shall submit the following information: 

(i) the results of reinjection well testing; 

(ii) based upon the results of testing and other studies, an estimate of the 

short-term and long-term reinjection rates that each suitable geologic 

formation is capable of receiving; 

(iii) the results of ground water modeling showing the effects of 

reinjection into suitable geologic formations on other aquifers, surface 

waters, and regional flow systems; and 

(k) all other information required by the EPA as part of the Class V UIC 

Program. 

(3) The department shall notify the applicant in writing, within 60 days after receipt of an 

application for a waiver, that the application does or does not contain all the information 

necessary for the department to make a determination. If the information from the 

supplemental submittal or any subsequent supplemental submittal is inadequate, the 

department shall notify the applicant in writing, within 30 days of receipt of the 

supplemental submittal, what additional information must be submitted. The department 

shall notify the applicant in writing when the application is deemed complete. 

New Rules V and VI (not reprinted here) describe the administrative steps that the Montana 

Department of Environmental Quality (DEQ) must follow in reviewing and deciding upon a 

waiver application. The length of time needed to go through the steps can be in excess of one 

year before a final decision is reached, and can be even longer if an interested party requests a 

hearing on the application. 

New Rule VIII establishes numerical discharge standards (BPJ limits comparable to BAT limits) 

for that portion of the CBNG produced water that cannot be reinjected and is granted a waiver. 

NEW RULE VIII TREATMENT-BASED EFFLUENT LIMITATIONS 

(1) If the department grants a waiver from the zero discharge requirement for all or a 

portion of the wastewater pursuant to [New Rules II and III], the amount of wastewater 

that obtains the waiver shall achieve the following minimum technology-based effluent 

limitations at the end of the pipe prior to discharge: 

(a) calcium average concentration between 0.1 mg/L and 0.2 mg/L; 

(b) magnesium average concentration between 0.1 mg/L and 0.6 mg/L; 

(c) sodium average concentration of 10 mg/L; 
Observations on a Montana Water Quality Proposal Page 13

(d) bicarbonate average concentration of 30 mg/L and instantaneous maximum 

concentration of 115 mg/L; 

(e) sodium adsorption ratio instantaneous maximum of 0.5; 

(f) electrical conductivity average concentration of 233 μmhos/cm; 

(g) total dissolved solids average concentration of 170 mg/L; 

(h) ammonia average concentration of 0.1 mg/L and instantaneous maximum 

concentration of 0.3 mg/L; and 

(i) arsenic concentration of <0.0001 mg/L. 

The rationale provided in the proposal is not very extensive. Even the rationale in the petition is 

not particularly detailed. It appears that the requirement to reinject is based on the desire to keep 

water in the aquifers from which it came or at least in other nearby aquifers from which it could 

be recovered later. BER acknowledges that the geologic formations in reasonable proximity to 

the coal seams may not be able to accept all of the CBNG produced water that has been 

withdrawn, and therefore has allowed the waiver process, albeit through a lengthy and 

complicated application procedure. When a waiver is granted, the discharge limits are intended 

to represent a minimum level of treatment. 

One other portion of the proposal offers some degree of flexibility and relief, where applicable. 

New Rule IX allows some of the CBNG produced water to be used for livestock watering. 

NEW RULE IX STOCK WATERING EXEMPTION (1) The requirements of [New Rules I 

through VIII] shall not apply to any quantity of wastewater used for stock watering 

purposes if all the following conditions are satisfied: 

(a) the surface owner and operator sign a written agreement to use the 

wastewater for stock watering purposes; 

(b) the wastewater is stored in a stock tank; and 

(c) the surface owner has obtained a beneficial use permit from the department of 

natural resources and conservation pursuant to Title 85, chapter 2, MCA. 

(2) The stock watering exemption shall be limited to the quantity of water for which the 

department of natural resources and conservation issues a beneficial use permit. 

G. Comparison of the Proposal to EPA Technology-Based Limits Procedures 

As previously noted at the start of the discussion of Item 2, the proposal does not follow the 

CWA guidelines for establishing technology-based limits. In this section, the technology-based 

requirements contained in the proposal are compared with the federal requirements for 

establishing BAT and BPJ technology-based limits. Discrepancies from the federal requirements 

are noted in several key portions of the proposal. The economic justification for the limits is 

based on a draft report that estimates costs for a much less stringent set of discharge standards 

than those required in the proposal. Furthermore, the proposal contains several apparent logical 

inconsistencies and drafting errors that would make the proposal difficult to administer and 

enforce. 

As a first step, the proposal imposes zero discharge. EPA has previously established BAT as 

zero discharge for some waste streams in its ELGs when it can make a compelling case that zero 
Observations on a Montana Water Quality Proposal Page 14

discharge is affordable and available to an industry. When EPA makes a zero discharge 

decision, it identifies at least one affordable and available alternative method for managing the 

effluent. However, in lead author Veil’s extensive NPDES experience (see footnote 2), neither 

EPA nor a delegated state tells dischargers exactly what technology or management must be used 

to achieve zero discharge. As explained in Section D above, BAT is a level of performance not a 

treatment technology. 

In contrast, the proposal not only requires zero discharge without a compelling justification but 

goes further to direct generators of CBNG produced water to reinject whenever possible. We are 

not aware of any justification for the injection mandate in the CWA, the NPDES regulations, or 

in the Montana regulations. We believe that this requirement oversteps the BER’s authority. 

The injection requirements go even farther out-of-bounds by specifying the type of geologic 

formations into which the water must be injected. 

The requirement to inject into a suitable geologic formation could introduce a shift in regulatory 

resources. If the CBNG produced water is discharged into Montana surface waters, the Montana 

DEQ will issue the permit and incur the administrative burden. On the other hand, if water 

generators are forced to inject into what presumably are shallow aquifers, the regulatory burden 

will shift to the EPA’s Region 8 office because Montana does not have delegated authority for 

the UIC Class V program. 

The second step of the proposal allows potential dischargers to apply for a waiver to the extent 

they can demonstrate that the suitable geologic formations either are not available nearby or do 

not have the porosity or other capacity-related properties to receive the water. Osborne and 

Adams (2005) recently reported that many of the shallow aquifers in the Powder River Basin do 

not readily accept injected water.3

 Earlier attempts to reinject CBNG produced water have had 

only limited success to date. It might be possible to enhance injection by injecting at very high 

pressures. However, EPA prohibits injection pressures that exceed the fracture pressure when 

injecting into Class I and Class V wells. 

The rationale in the proposal uses the example of CBNG production in the San Juan Basin of 

New Mexico. In that basin, most of the CBNG produced water is reinjected. However, the 

water is much saltier than that found in most of the Powder River Basin. It is not amenable to 

beneficial reuse without expensive treatment. In the San Juan Basin, the CBNG is injected into 

deep formations where it cannot be readily retrieved. The San Juan Basin example is not similar 

to the Powder River Basin and should not be used to justify a dissimilar water management 

approach. 

If a CBNG produced water generator wants to apply for a waiver, the application informational 

requirements outlined in New Rule IV are very complicated and rigorous. Assuming that the 

operator can cost-effectively compile appropriate information to justify a waiver, the review 

process is quite lengthy, possibly lasting for more than one year. The individual steps are shown 

 

3 Osborne, T.J., and J.E. Adams, 2005, “Opportunities and Limitations of CBNG Produced Water Management 

Alternatives in the Powder River Basin,” presented at the 12th International Petroleum Environmental Conference, 

Houston, TX, November 7–11. 
Observations on a Montana Water Quality Proposal Page 15

in Table 1. Three steps, identified by A, B, and C in the table, have undetermined length and 

could extend the waiver approval process even longer. 

Table 1 – Steps and time line for Montana DEQ review of waiver application 

Step Maximum Days for this Step 

Cumulative 

Days 

Application submitted 0 0 

DEQ notifies applicant of completeness or 

incompleteness 

60 60 

If incomplete, applicant provides supplemental 

information 

A (time needed to prepare and 

resubmit material) 

60+A 

DEQ notifies applicant of completeness 30 90+A 

DEQ prepares preliminary decision 180 270+A 

If EIS is needed B (time needed to conduct EIS) 270+A+B 

Public comment period 60 330+A+B 

If hearing is requested, hearing is scheduled 

and held 

C (time needed to schedule and 

hold hearing) 

330+A+B+C 

DEQ issues final decision 60 390+A+B+C 

Final decision becomes effective 30 420+A+B+C 

The Montana DEQ staff may not have the necessary resources to review and make decisions on 

numerous waiver applications in a timely manner, thereby adding to the length of the review 

schedule. Operators are likely to be reluctant to undertake projects when the regulatory outcomes 

are uncertain and will not be known for a year or more. 

In the third step of the proposal, operators that have made a successful waiver application may 

discharge if they can meet the effluent limits outlined in New Rule VIII. This part of the 

proposal contains several apparent drafting errors. First, the proposal calls for “minimum

technology-based effluent limitations” [emphasis added]. The numerical limits in (1) (a) – (i) are 

most likely intended to be maximum limits, not minimum limits. Second, for several parameters, 

the average concentrations must be kept within a range (e.g., the calcium average concentration 

must be between 0.1 mg/L and 0.2 mg/L. There is no apparent reason to set a “minimum” 

standard as a range, nor is there any reason to limit concentrations to a range. Under this 

provision, a calcium average of either 0.08 mg/L or 0.3 mg/L is out of compliance. 

Of greater concern are the actual numerical values that have been established for each parameter. 

Neither the proposal nor the petition explains how the numerical values were selected. The 

proposal does not identify any one model BAT technology but suggests that the limits can be 

achieved cost-effectively by both reverse osmosis and ion exchange. Either technology can 

achieve a wide range of results depending on the concentrations in the influent stream and how 

the system is operated and maintained. For example, different types of ion exchange resins are 

available that will yield different performance. The frequency of backwashing, replacement of 

resins, and the nature of pretreatment steps all contribute to how well the system will perform 

and how costly the treatment process will be. This is not reviewed in the proposal or in the 

petition. 

Another consideration is the conditions under which the system must operate over the long term. 

Most systems will perform more effectively and consistently when they are situated in an 
Observations on a Montana Water Quality Proposal Page 16

environment that is sheltered from temperature and other climatic swings. A reverse osmosis 

system in a heated factory building is likely to perform better than a comparable system left 

outside at an exposed field site. In Section D above, the importance of long-term treatment 

performance and its inherent variability were discussed in relation to establishing valid BAT 

limits. The proposal offers no evidence that it considered either long-term performance 

variability at one facility or the variability from one facility to another when setting technologybased limits. 

Section C above outlined the factors that EPA needed to consider when developing BAT limits. 

The same factors apply to BPJ limits that are set either by permit writers for individual permits 

or for this proposal as it sets BPJ limits for an entire category of effluent. The proposal offers 

limited discussion of these factors. Table 2 shows the factors and how they relate to several 

types of possible technology. There are many other approaches for managing CBNG produced 

water that have pros and cons. They are not shown in Table 2, but may be useful in certain sitespecific cases. Examples of approaches that have been used can be found in ALL Consulting 

(2003)4 and Veil et al. (2004).5

The proposal and the petition make various claims about the affordability of reinjection and 

treatment to achieve the proposed limit as they relate to the overall wellhead price of natural gas. 

Some of these cost estimates were derived from a 2003 draft EPA study6

 that was clearly marked 

“InterAgency Draft Report — DO NOT QUOTE OR CITE” on each page. EPA has never 

released that report; therefore, it is inappropriate to use the cost figures contained therein as the 

basis for supporting new regulations. There are at least two more recent reports that provide 

better-justified cost estimates. One was prepared by CDM in December 2004,7 and the other 

report, prepared by Advanced Resources International, was released in January 2006.8 

A related economic issue that appears to have been overlooked is that the draft EPA study as 

well as the CDM and DOE studies evaluate the cost of achieving a different, and much less 

stringent, set of discharge standards from those required by the proposal. The cost for treating 

water or wastewater increases as the target treatment standards are made more stringent. Thus 

the costs estimated by the cited reports underestimate the actual costs that would be associated 

with meeting the proposal’s strict limits, and therefore are not fully relevant as rationale for 

supporting new limits. 

 

4

 ALL Consulting, 2003, “Handbook on Coal Bed Methane Produced Water: Management and Beneficial Use 

Alternatives,” prepared by ALL Consulting for the Ground Water Protection Research Foundation, U.S. Department 

of Energy, and U.S. Bureau of Land Management, July.

5 Veil, J.A., M.G. Puder, D. Elcock, and R.J. Redweik, Jr., 2004, “A White Paper Describing Produced Water from 

Production of Crude Oil, Natural Gas, and Coal Bed Methane,” prepared by Argonne National Laboratory for the 

U.S. Department of Energy, National Energy Technology Laboratory, January, 87 pp. 

6 U.S. Environmental Protection Agency, 2003, “Guidance for Developing Technology-Based Limits for Coalbed 

Methane Operations: Economic Analysis of the Powder River Basin,” draft, February. 

7 CDM, 2004, “Technical Review and Analysis of Kuipers’/NPRC Documents Related to the Management of 

CBNG Produced Water in the Powder River Basin,” prepared for the Petroleum Association of Wyoming, 

December 21. 

8

 Bank, G.C., and V.A. Kuuskraa, 2006, “The Economics of Powder River Basin Coalbed Methane Development,” 

prepared for U.S. Department of Energy by Advanced Resources International, January. 
Observations on a Montana Water Quality Proposal Page 17

Table 2 – Comparison of CBNG produced water management technologies in relation to 

the CWA factors for technology-based limits 

BAT/BPJ 

Factor 

Shallow 

Reinjection 

Discharge after 

Treatment per 

Proposal 

Deep 

Reinjection 

Discharge after 

Less Stringent 

Treatment 

Managed 

Irrigation 

Age of 

equipment and 

facilities 

New – not an 

issue 

New – not an 

issue 

New – not an 

issue 

New – not an issue New – not an 

issue 

Process 

employed 

Not technically 

possible in many 

locations; waiver 

provision is 

complicated and 

lengthy 

May not be 

technically 

possible to meet 

the limits 

Not technically 

possible in 

some locations 

Process is possible 

if limits are based 

on actual long-term 

performance 

Process is 

technically 

feasible 

Engineering 

aspects of 

control 

technologies 

Not technically 

possible in many 

locations 

May not be 

technically 

possible to meet 

the limits 

Not technically 

possible in all 

locations 

Possible if limits are 

based on actual 

long-term 

performance 

Requires 

careful 

oversight 

and 

management 

Process 

changes 

Need to look for 

suitable geologic 

formations to 

inject water; need 

to avoid 

formations that 

would impede 

CBNG recovery 

Would not be able 

to produce CBNG 

if the water cannot 

be treated 

Need to find 

formations to 

inject water 

Need to construct 

and operate 

treatment system 

Need to 

manage 

irrigation and 

provide 

chemical 

supplements 

Cost Cost of drilling 

and operating 

injection wells is 

medium to high, 

but may not be 

able to find 

suitable 

formations 

If the technology 

is even possible, it 

is likely to have a 

high cost 

Cost of drilling 

and operating 

injection wells is 

medium to high 

Medium to high – 

depends on limits 

Medium, but 

landowners 

see a benefit 

through 

enhanced 

crop yield 

Non-water 

quality 

environmental 

impacts 

(including 

energy) 

Injection may 

require fracturing 

of rocks; may 

require 

pretreatment 

before injection; 

some energy cost 

for injection 

Loss of part of the 

water for future 

use unless it is 

subsequently 

taken out of the 

river; some will 

infiltrate; need to 

manage disposal 

of blowdown/ 

concentrate 

stream 

Loss of water 

for future 

recovery; may 

require 

pretreatment 

before injection; 

some energy 

cost for injection 

Loss of part of the 

water for future use 

unless it is 

subsequently taken 

out of the river; 

some will infiltrate; 

need to manage 

disposal of 

blowdown/ 

concentrate stream 

Water is 

beneficially 

reused; 

some energy 

costs for 

irrigation; 

need to haul 

large 

amounts of 

chemical 

supplements 

The proposed limits create an internally inconsistent situation. The SAR is calculated by a 

formula that combines the milliequivalents of sodium, calcium, and magnesium.9

 If the 

proposed average effluent limits for each of these parameters are entered into the SAR equation, 

 

9 The formula for calculating SAR, an explanation of milliequivalents vs. mg/L, and a handy SAR calculation tool 

are provided at: http://www.coopext.colostate.edu/TRA/PLANTS/index.html#http://www.colostate.edu/

Depts/CoopExt/TRA/PLANTS/sar.html. 
Observations on a Montana Water Quality Proposal Page 18

they result in SAR values of 2.5 to 5.3. (The SAR is expressed here as a range because the 

calcium and magnesium limits are both expressed as a range.) The proposed SAR effluent limit 

is 0.5 maximum. Thus it appears that discharges complying with the three component parts of 

the SAR equation will still be in violation of the SAR limit. This presents an unreasonable 

regulatory burden. 

3. Does the Proposal Preclude the Use of Other Innovative or Beneficial Technologies? 

The proposal precludes the use of water management options other than reinjection, discharge 

following treatment to very strict standards, or use for stock watering with special permission. 

The proposal would also restrict the introduction of any future innovative technologies for 

managing CBNG produced water. 

The proposal requires reinjection to suitable geologic formations wherever possible. When 

reinjection is not possible, and if the operator can make a successful waiver application, some or 

all of the CBNG produced water can be discharged as long as the effluent meets some very strict 

standards. With the exception of New Rule IX, which provides an exemption for CBNG water 

used for livestock watering, no other management options are permitted for CBNG water. This 

intentional restriction of regulatory and management options effectively precludes the use of 

CBNG water for many beneficial purposes. Some of the existing uses of CBNG produced water 

provide affordable management for operators while providing direct benefit to landowners. For 

example, managed irrigation has proven successful in some Powder River Basin applications. In 

a recent paper, Harvey et al. (2005) describe several case studies of managed irrigation to 

beneficially reuse CBNG produced water.10 Operators may be interested in other uses such as 

off-channel impoundments that can provide livestock watering and recreational opportunities for 

landowners. The wording of the proposal would not allow these valid and beneficial uses of 

water nor would it encourage development of more cost-effective water management 

technologies. 

4. Are the Proposed Discharge Standards Stricter Than Needed to Meet Montana Water 

Quality Standards? 

The proposed effluent limits are much stricter than necessary to meet water quality standards in 

Montana water bodies. Dischargers must treat to levels significantly cleaner than the receiving 

waters. 

The proposal appears to blur the distinction between technology-based limits and water-qualitybased limits. Technology-based limits ignore the potential impact on water quality and are only 

concerned with the performance of one or more technologies. Thus, it is inappropriate to justify 

a technology-based limit by saying it is necessary to achieve water quality. Water-quality-based 

limits, on the other hand, ignore the availability and cost of technology and rely solely on what is 

needed to protect water quality. In some situations, technology-based limits will be stricter, 

while in other situations water-quality-based limits will be stricter. 

 

10 Harvey, K.C., D.E. Brown, and A.J. DeJoia, 2005, “Managed Irrigation for the Beneficial Use of Coalbed 

Natural Gas Produced Water in the Powder River Basin,” presented at the 12th International Petroleum 

Environmental Conference, Houston, TX, November 7–11. 
Observations on a Montana Water Quality Proposal Page 19

In the proposal, there is some question about the validity of the proposed technology-based 

effluent limits. Insufficient justification is presented about the achievability and affordability of 

the limits. The proposed effluent limits are compared with the existing Montana water quality 

standards in Table 3. For several of the parameters in the proposed effluent limits, there are no 

water quality standards. For those parameters in Table 3 that do have water quality standards, 

the water quality standards are in all cases more lenient than the proposed effluent standards. In 

other words, dischargers must treat to levels significantly cleaner than the receiving waters. 

Table 3 – Comparison of proposed effluent limits to water quality standards 

Parameter 

Proposed Effluent 

Limits Water Quality Standardsa

Calcium 0.1 mg/L to 0.2 mg/L 

average 

No standard 

Magnesium 0.1 mg/L to 0.6 mg/L 

average 

No standard 

Sodium 10 mg/L average No standard 

Bicarbonate 30 mg/L average 

115 mg/L maximum 

No standard 

SAR 0.5 maximum a) From 11/1 to 3/1: 

 i) Rosebud Creek and Tongue River – 5.0 average, 7.5 maximum 

 ii) Powder and Little Power Rivers – 6.5 average, 9.75 maximum 

b) from 3/2 to 10/31: 

 i) Rosebud Creek and Tongue River - 3.0 average, 4.5 maximum 

 ii) Powder and Little Power Rivers - 5.0 average, 7.5 maximum 

EC 233 μmhos/cmb 

average 

a) From 11/1 to 3/1: 

 i) Rosebud Creek and Tongue River – 1,500 μS/cmb average, 

 2,500 μS/cm maximum 

 ii) Powder and Little Power Rivers– 2,500 μS/cm average, 2,500 μS/cm 

 maximum 

b) from 3/2 to 10/31: 

 i) Rosebud Creek and Tongue River – 1,000 μS/cm average, 

 1,500 μS/cm maximum 

 ii) Powder and Little Power Rivers– 2,000 μS/cm average, 2,500 μS/cm 

 maximum 

Total dissolved 

solids 

170 mg/L average No standard 

Ammonia 0.1 mg/L average 

0.3 mg/L maximum 

Expressed as a function of pH, temperature, and whether early life stage of 

fish is present. Average values range from 0.179 mg/L to 10.8 mg/L. 

Maximum values range from 0.885 mg/L to 48.8 mg/L 

Arsenic <0.0001 mg/L 

[presumed to be a 

maximum] 

0.15 mg/L average 

0.34 mg/L maximum 

a Based on Montana Numeric Water Quality Standards Circular WQB-7. 

b

 1 μmho/cm = 1 uS/cm, although the units are written differently in the proposed effluent limits and the 

water quality standards. 

If the proposed effluent limits truly represent BAT and encompass the necessary technologybased factors previously described, that situation is appropriate and acceptable, as noted above. 

However, until sufficient justification is provided, the proposed effluent limits should not be 

portrayed as BAT. It seems inappropriate to require treatment to levels far below water quality 

standards. Treatment to some less stringent effluent limits could be more available, more 
Observations on a Montana Water Quality Proposal Page 20

affordable, and would still ensure protection of water quality standards downstream from 

discharges. 

5. Summary of Key Observations 

- The proposal inconsistently characterizes the value of CBNG produced water. In some 

places, the proposal refers to it as “wastewater” and emphasizes that some of its 

constituents are “hazardous parameters.” In other places, the proposal acknowledges the 

water’s value in both quantity and quality and implements measures to ensure that the 

water is available for future beneficial use. This inconsistency is misleading. 

- The proposal does not follow the CWA guidelines for establishing technology-based 

limits. The most notable excursion from the guidelines is the proposal’s attempt to 

mandate the use of just one or two specific technologies. The BER is within its rights to 

require zero discharge, assuming that it can show that other water management 

alternatives are available and affordable. However, the BER may not specify the type of 

technology that must be used to achieve zero discharge. In addition to the procedural 

issues raised by the proposal, this strategy effectively blocks the opportunity for other 

beneficial and innovative technologies to be used. 

- The proposal includes numerical technology-based effluent limits. They are very 

stringent, and no detailed rationale is provided to explain why they were selected. 

Traditional methods to evaluate BAT and technology-based limits were not followed. 

The economic justification for the limits is based on a draft report that estimates costs for 

a much less stringent set of discharge standards than those required in the proposal. 

- The effluent limits are much stricter than necessary to meet water quality standards in 

Montana water bodies. If the proposal had properly demonstrated that these strict limits 

represented BAT, they could be employed. The proposal does not make such a 

demonstration, and therefore the limits appear to be unnecessarily stringent. 
Observations on a Montana Water Quality Proposal Page 21

Appendix A – Permit Limit Guidelines Used by Maryland Department of Environment in 

Late 1980s 
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