[Federal Register Volume 66, Number 146 (Monday, July 30, 2001)]
[Proposed Rules]
[Pages 39295-39298]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-18886]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 131

[FRL-OW-7020-4]


Water Quality Standards; Withdrawal of Federal Nutrient Standards 
for the State of Arizona

AGENCY: Environmental Protection Agency.

ACTION: Proposed rule.

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SUMMARY: In 1976, EPA promulgated Federal criteria for nutrients in 
Arizona. The Federal criteria consisted of numeric ambient water 
quality criteria for nutrients for eleven river segments and narrative 
water quality criteria for nutrients applicable to all surface waters 
in Arizona. Arizona has now adopted its own numeric and narrative water 
quality criteria for nutrients, which EPA has approved. Arizona has 
also established and EPA has approved implementation procedures for its 
narrative nutrient water quality criteria. Therefore, EPA is proposing 
to withdraw the Federal criteria for nutrients applicable in Arizona. 
EPA is providing an opportunity for public comment on the withdrawal of 
the Federal nutrient criteria because the State's water quality 
criteria for nutrients, while protective of designated uses, in some 
cases may be less stringent than the corresponding federally 
promulgated nutrient criteria.

DATES: EPA will accept public comments on this proposed rulemaking 
until September 28, 2001. Comments postmarked after this date may not 
be considered.

ADDRESSES: Send written comments to Gary Sheth, EPA, Region 9 (WTR-5), 
Water Division, 75 Hawthorne Street, San Francisco, CA 94105. Written 
comments should include an original plus three copies. Electronic 
comments are encouraged and should be submitted to [email protected]. 
Electronic comments must be submitted as an ASCII file or a WordPerfect 
file. The supporting record for this rulemaking may be inspected 
(Monday through Friday, 8:00 a.m. to 4:30 p.m. excluding legal 
holidays) at EPA, Region 9, Water Management Division, 75 Hawthorne 
Street, San Francisco, CA 94105. For access to docket materials, please 
call 415-744-2125. A reasonable fee will be charged for photocopies.

FOR FURTHER INFORMATION CONTACT: Gary Sheth (415-744-2008, 
[email protected]) EPA, Region 9 (WTR-5), Water Division, 75 Hawthorne 
Street, San Francisco, CA 94105, or Jennifer Wigal (202-260-5177, 
[email protected]) EPA Headquarters, Office of Water (4305), 1200 
Pennsylvania Ave NW, Washington, DC 20460.

SUPPLEMENTARY INFORMATION:
I. Potentially Affected Entities
II. Background
    A. What Are the Statutory and Regulatory Requirements Relevant 
to this Action?
    B. What Actions Have EPA and Arizona Taken in the Past Relating 
to Water Quality Standards for Nutrients in the State?
    C. What Water Quality Standards for Nutrients Currently Apply in 
Arizona?
    D. What Water Quality Standards Will Apply if EPA Withdraws the 
Federal Nutrient Criteria in Arizona?
III. Administrative Requirements

I. Potentially Affected Entities

    Citizens concerned with water quality in Arizona may be interested 
in this proposed rulemaking. Entities discharging nitrogen or 
phosphorous to waters of the United States in Arizona could be affected 
by this proposed rulemaking because water quality criteria are used in 
determining National Pollutant Discharge Elimination System (NPDES) 
permit limits. Potentially affected entities include:

------------------------------------------------------------------------
                                             Examples of potentially
                Category                        affected entities
------------------------------------------------------------------------
Industry...............................  Industries discharging
                                          nutrients to surface waters in
                                          Arizona.
Municipalities.........................  Publicly-owned treatment works
                                          discharging nutrients to
                                          surface waters in Arizona.
------------------------------------------------------------------------

    This table is not intended to be exhaustive, but rather provides a 
guide for readers regarding NPDES regulated entities that could 
potentially be affected by this action. This table lists the types of 
entities that EPA is now aware could potentially be affected by this 
action. Other types of entities not listed in the table could also be 
affected. If you have questions regarding the applicability of this 
action to a particular entity, consult the person listed in the 
preceding FOR FURTHER INFORMATION CONTACT section.

[[Page 39296]]

II. Background

A. What Are the Statutory and Regulatory Requirements Relevant to This 
Action?

    Section 303(c) (33 U.S.C. 1313(c)) of the Clean Water Act (CWA or 
Act) directs States, with oversight from EPA, to adopt water quality 
standards to protect the public health and welfare, enhance the quality 
of water and serve the purposes of the Act. States are required to 
develop water quality standards for waters of the United States within 
the State. Section 303(c) provides that a water quality standard shall 
include the designated use or uses to be made of the water and the 
water quality criteria necessary to protect those uses. States may also 
include in their water quality standards policies generally affecting 
the standards' application and implementation. 40 CFR 131.6(f); 40 CFR 
131.13. States are required to review their water quality standards at 
least once every three years and, if appropriate, revise or adopt new 
standard. 33 U.S.C. 1313(c)(2). States are required to submit the 
results of their reviews to EPA. EPA then reviews the State's standards 
for consistency with the CWA and EPA's implementing regulations at 40 
CFR Part 131 and approves or disapproves any new or revised standards. 
33 U.S.C. 1313(c)(3). Section 303(c)(4) of the CWA authorizes EPA to 
promulgate water quality standards when necessary to supersede 
disapproved State water quality standards, or in any case where the 
Administrator determines that new or revised standards are necessary to 
meet the requirements of the CWA.
    EPA will issue a rule to withdraw Federal water quality standards 
promulgated for a State when the State adopts, and EPA approves, State 
water quality standards that meet the requirements of the CWA and the 
implementing Federal regulations. Because the State's water quality 
criteria for nutrients, while protective of designated uses, may in 
some cases be less stringent than the federally promulgated standards, 
EPA is providing an opportunity for the public to comment on the 
proposed withdrawal of the Federal nutrient criteria for Arizona. EPA 
requests comment on whether there are any waterbodies in Arizona where 
the Federal nutrient criteria should not be removed. For such 
waterbodies, EPA solicits data documenting existing conditions which 
indicate that designated uses would not be protected by Arizona's 
numeric or narrative nutrient water quality criteria.

B. What Actions Have EPA and Arizona Taken in the Past Relating to 
Water Quality Standards for Nutrients in the State?

    In 1976, EPA determined that water quality standards for nutrients 
submitted by Arizona as of that time did not meet the CWA's 
requirements. EPA promulgated Federal numeric nutrient criteria for 
total phosphates applicable to eleven river segments in Arizona, 
Federal numeric nutrient criteria for total nitrates applicable to four 
waterbodies, and Federal narrative nutrient criteria applicable to all 
surface waters of Arizona. See 40 CFR 131.31(a); 41 FR 25000 (June 22, 
1976). Although EPA used the phrase nutrient standards to describe the 
water quality criteria for nutrients codified at 40 CFR 131.31(a), in 
today's proposal, EPA is using the more precise term criteria to refer 
to Federal water quality criteria for nutrients for Arizona that EPA is 
proposing to withdraw.
    Since EPA's promulgation of nutrient criteria for Arizona, the 
Arizona Department of Environmental Quality (ADEQ) in a series of 
actions adopted numeric nutrient criteria for total nitrogen and total 
phosphorous applicable to specific water bodies in Arizona. See Arizona 
Administrative Code, R18-11-109, 11-110, and 11-112. Arizona has also 
adopted narrative nutrient criteria applicable to all surface waters of 
the State. See Arizona Administrative Code, R18-11-108. Arizona's 
narrative nutrient criteria provide that navigable waters shall be free 
from pollutants in amounts or combinations that cause the growth of 
algae or aquatic plants that inhibit or prohibit the habitation, growth 
or propagation of other aquatic life or that impair recreational uses. 
See Arizona Administrative Code, R18-11-108.A.5. Since EPA's 
promulgation of nutrient water quality criteria in 1976, EPA has 
approved the numeric and narrative water quality criteria for nutrients 
adopted by Arizona. See, e.g., EPA's Federal Register notices of 
approvals at 53 FR 4209 (Feb. 12, 1988); 58 FR 62124 (Nov. 24, 1993); 
60 FR 51793 (Oct. 3, 1995).
    Arizona's adopted and approved numeric water quality criteria for 
nutrients are based on total phosphorous and total nitrogen whereas the 
numeric water quality criteria for nutrients promulgated by EPA in 1976 
are based on total phosphates and total nitrates. Total phosphorous and 
total nitrogen are more encompassing measurements of the presence of 
these types of nutrients than total phosphates and total nitrates, for 
which EPA promulgated water quality criteria in 1976. Elemental 
phosphorous and nitrogen can be present in different forms under 
different conditions (for example, as phosphates and nitrates). For 
this reason, to quantify the total phosphorous and nitrogen present, 
EPA recommends measuring concentrations of total phosphorous and total 
nitrogen. Although EPA is not able to directly compare Arizona's 
nutrient criteria based on total phosphorous and total nitrogen with 
the Federal criteria based on total phosphates and total nitrates, the 
CWA and EPA's regulations at 40 CFR 131.11 only require that States 
adopt criteria that are scientifically defensible and sufficiently 
detailed to protect the designated uses of the waterbodies. When EPA 
approved these criteria, EPA determined that they met this requirement 
and adequately protected Arizona waters from nutrient overenrichment 
(the same objective of the 1976 federal nutrients water quality 
criteria). Arizona's numeric nutrient criteria are also consistent with 
EPA's current guidance recommending water quality criteria for the 
control of nutrients be expressed in terms of total nitrogen and total 
phosphorous. See Nutrient Criteria Technical Guidance Manual: Lakes and 
Reservoirs, EPA-822-B-00-001; Ambient Water Quality Criteria 
Recommendations: Lakes and Reservoirs in Nutrient Ecoregion II, EPA-
822-B-00-007; Ambient Water Quality Criteria Recommendations: Rivers 
and Streams in Nutrient Ecoregion II, EPA 822-B-00-015; Ambient Water 
Quality Criteria Recommendations: Rivers and Streams in Nutrient 
Ecoregion III, EPA 822-B-00-016. In short, the State's numeric and 
narrative nutrient criteria adopted from 1976 to 1996, along with the 
implementation procedures for the narrative nutrient criteria, fully 
protect the designated uses of Arizona's surface waters, and as such 
are consistent with the CWA and the implementing Federal regulations at 
40 CFR 131.11. (For more detailed information on EPA's analysis, see 
EPA's approval decisions contained in the docket to this rulemeaking.)
    In EPA's action taken in 1993, EPA approved the numeric and 
narrative nutrient criteria adopted by the State, but disapproved the 
absence of implementation procedures for the narrative nutrient water 
quality criteria. In January 1996, EPA proposed Federal water quality 
standards addressing several deficiencies in Arizona's water quality 
standards, which included the identification of appropriate procedures 
and methods for interpreting and implementing the State's narrative

[[Page 39297]]

nutrient criteria. See 61 FR 2766 (January 29, 1996). Also in January 
1996, ADEQ established implementation procedures for its narrative 
nutrient water quality criteria (see Arizona's Implementation 
Guidelines for the Narrative Nutrient Standard). On April 26, 1996, EPA 
approved these implementation procedures. In the preamble to the final 
rule promulgating other water quality standards elements for Arizona, 
EPA explained that promulgation of Federal implementation procedures 
for Arizona's narrative nutrient criteria was no longer necessary 
because the State had identified its own implementation procedures. See 
61 FR 20686 (May 7, 1996). Although EPA did not specifically address 
the continuing need for the 1976 Federal nutrient criteria, in its 
decision not to promulgate Federal implementation procedures, EPA 
observed that Arizona's numeric and narrative nutrient criteria, as 
supplemented by the State's newly established implementation 
procedures, were consistent with the CWA and that no new Federal water 
quality standard to implement the State's narrative criteria was 
necessary to meet the CWA's requirements. See 61 FR 20692 (May 7, 
1996). Consistent with this earlier finding, EPA has determined that 
the 1976 Federal criteria for nutrients for Arizona waters are 
redundant and no longer necessary. EPA is therefore proposing to 
withdraw the Federal water quality criteria for nutrients applicable to 
Arizona surface waters at 40 CFR 131.31(a).

C. What Water Quality Standards for Nutrients Currently Apply in 
Arizona?

    Since EPA's 1976 promulgation of water quality criteria for 
nutrients for Arizona surface waters, the State has adopted numeric 
nutrient water quality criteria applicable to specified surface waters 
of the State, adopted narrative nutrient water quality criteria 
applicable to all of its surface waters, and established implementation 
procedures for its narrative nutrient water quality criteria. These 
individual adoptions were approved by EPA between 1976 and 1996.
    Currently, both the Federal and State nutrient criteria apply in 
Arizona. This includes the Federal numeric and narrative nutrient 
criteria (40 CFR 131.31(a)); the State's numeric nutrient water quality 
criteria (R18-11-109, 11-110, and 11-112); the State's narrative 
nutrient water quality criteria (R18-11-108); the State's regulation 
regarding nutrient waivers (R18-11-115); and the State's implementation 
procedures established for its narrative nutrient water quality 
criteria.

D. What Water Quality Standards Will Apply If EPA Withdraws the Federal 
Nutrient Criteria in Arizona?

    The goal of EPA's 1976 rulemaking in Arizona was to establish water 
quality criteria to protect the designated uses of Arizona surface 
waters. EPA may withdraw federally promulgated water quality standards 
after the State adopts, and EPA approves, water quality standards that 
meet the requirements of the CWA and the implementing Federal 
regulations. EPA is proposing to withdraw the Federal numeric and 
narrative nutrient criteria at 40 CFR 131.31(a). If finalized, the 
applicable nutrient criteria in Arizona will consist of the State's own 
numeric and narrative nutrient criteria along with the corresponding 
implementation procedures for the narrative criteria. Not affected by 
this proposal are federal water quality standards codified at 40 CFR 
131.31(b) & (c), which among other things, designate fish consumption 
as a use for certain waters, and require implementation of a monitoring 
program regarding mercury's effects on wildlife. These provisions 
remain in effect.
    Table 1 below displays the Federal numeric criteria for nutrients 
and the State's corresponding criteria. The waterbody segments listed 
in Table 1 are the waters for which Federal numeric nutrient criteria 
apply. The applicable Federal nutrient criteria and the corresponding 
State nutrient criteria are listed for each water body. Because the 
Federal and State nutrient criteria are based on measurements of 
different parameters (i.e., total phosphates and total nitrates versus 
total phosphorous and total nitrogen), this table does not provide a 
direct comparison of the Federal and State nutrient criteria but rather 
describes how individual waters that are currently covered by the 
Federal criteria for nutrients will be covered by Arizona's water 
quality standards. For waterbodies or waterbody segments listed in rows 
4, 8, 9 and 11, Arizona has adopted numeric nutrient water quality 
criteria for either total nitrogen, total phosphorus, or both. In 
addition to the numeric nutrient criteria in Table 1 for the listed 
stream segments, Arizona has adopted numeric nutrient criteria for 
additional stream segments not covered by the Federal nutrient 
criteria. EPA approved Arizona's numeric nutrient criteria because the 
criteria were derived using sound science and are protective of the 
designated uses of those waters. Readers interested in viewing 
Arizona's numeric nutrient criteria not listed in Table 1 should 
consult Arizona's water quality standards (R18-11-109, 11-110, and 11-
112).
    For waterbodies or waterbody segments where Arizona has not adopted 
numeric nutrient water quality criteria to replace the Federal numeric 
water quality criteria for nutrients (the waters listed in rows 1, 2, 
3, 5, 6, and 10), the State's narrative nutrient criteria apply. The 
narrative nutrient criteria, in conjunction with Arizona's 
Implementation Guidelines for the Narrative Nutrient Standard, will 
provide the same intended level of protection as the Federal criteria 
by fully protecting the designated uses of these waters because it 
allows for consideration of site-specific factors. Indeed, when 
necessary, narrative criteria with the appropriate implementation 
procedures can be used to obtain quantitative measures having a greater 
degree of precision and site specificity than a single numeric target. 
EPA reviewed and approved Arizona's narrative nutrient criteria and the 
Implementation Guidelines for the Narrative Nutrient Standard as being 
scientifically defensible and consistent with the CWA and EPA's 
implementing regulations at 40 CFR 131.11.

           Table 1.--Federal Nutrient Criteria in CFR 131.31(a) and Arizona Numeric Nutrient Criteria
----------------------------------------------------------------------------------------------------------------
                                           Federal criteria at 40 CFR 131.31  Arizona criteria (mg/L) (mean/90th
                                             (mg/L) (mean/90th percentile)              percentile/max)
            Waterbody segment            -----------------------------------------------------------------------
                                          Total phosphates   Total nitrates   Total phosphorus   Total nitrogen
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1. Colorado River from Utah border to            0.04/0.06               4/7               nnc               nnc
 Willow Beach...........................
2. Colorado River from Willow Beach to           0.06/0.10              5/--               nnc               nnc
 Parker Dam.............................
3. Colorado River from Parker Dam to             0.08/0.12               5/7               nnc               nnc
 Imperial Dam...........................
4. Colorado River from Imperial Dam to           0.10/0.10               5/7      nnc/0.33/nnc      nnc/2.50/nnc
 Morelos Dam............................

[[Page 39298]]

 
5. Gila River from New Mexico border to          0.50/0.80             --/--               nnc                NA
 San Carlos Reservoir (excluding the San
 Carlos Reservoir)......................
6. Gila River from San Carlos Reservoir          0.30/0.50             --/--               nnc                NA
 to Ashurst Hayden Dam (including San
 Carlos Reservoir)......................
7. San Pedro River......................         0.30/0.50             --/--               nnc                NA
8. Verde River (except Granite Creek)...         0.20/0.30             --/--    0.10/0.30/1.00                NA
9. Salt River above Roosvelt Lake                0.20/0.30             --/--    0.12/0.30/1.00                NA
 (except Pinal Creek)...................
10. Santa Cruz River from international          0.50/0.80             --/--               nnc                NA
 boundary near Nogales to Sahuarita.....
11. Little Colorado River above Lyman            0.30/0.50             --/--    0.20/0.30/0.75               NA
 Reservoir..............................
----------------------------------------------------------------------------------------------------------------
--: No Federal numeric Nutrient Criteria were promulgated.
nnc: The State's narrative nutrient water quality criteria apply in conjunction with the State's implementation
  procedures.
NA: EPA has not presented the State's nutrient criteria for total nitrogen for these waters because these waters
  were not subject to the 1976 Federal nutrient water quality criteria.

    EPA is developing waterbody-type guidance describing the techniques 
for assessing the trophic state of a waterbody and methodologies for 
deriving nutrient water quality criteria appropriate to different 
geographic regions. Separate guidance has been developed for rivers and 
lakes; guidance for coastal waters and wetlands is underway. For 
freshwaters, the guidance recommends that approaches for developing 
nutrient water quality criteria address total nitrogen, total 
phosphorous, chlorophyll-a, and algal turbidity. EPA has also published 
recommended ecoregion-specific nutrient water quality criteria for 
States to use as guidance in adopting water quality standards. See 66 
FR 1671 (January 9, 2001). EPA has published nutrient water quality 
criteria guidance for the ecoregions contained within Arizona for 
rivers and streams and for certain lakes and reservoirs. EPA intends 
these recommended water quality criteria to serve as guidance for 
States as they develop and update their own nutrient water quality 
criteria. If, in the future, new data or information suggests that the 
State's nutrient criteria should be revised, EPA will work with Arizona 
to support and assist in adoption of new or revised water quality 
criteria for nutrients.

III. Administrative Requirements

    This proposed withdrawal of Federal criteria is deregulatory in 
nature and would impose no additional regulatory requirements or costs 
on anyone. Therefore, it has been determined that this proposed action 
is not a ``significant regulatory action'' under the terms of Executive 
Order 12866 (58 FR 51735, October 4, 1993) and accordingly is not 
subject to review by the Office of Management and Budget nor is it 
subject to Executive Order 13211 (66 FR 28355, May 22, 2001). For the 
same reason, pursuant to section 605(b) of the Regulatory Flexibility 
Act (5 U.S.C. 601 et seq.), I certify that this action will not have a 
significant economic impact on a substantial number of small entities. 
EPA has determined that this action contains no Federal mandates for 
State, local or tribal governments, or the private sector, nor does it 
contain any regulatory requirements that might significantly or 
uniquely affect small governments. Thus, today's action is not subject 
to the requirements of sections 202, 203 and 205 of the Unfunded 
Mandates Reform Act (Public Law 104-4). Further, this action does not 
significantly or uniquely affect the communities of tribal governments, 
as specified by Executive Order 13084 (63 FR 27655, May 10, 1998). This 
action will not have substantial direct effects on the States, on the 
relationship between the national government and the States, or on the 
distribution of power and responsibilities among the various levels of 
government, as specified in Executive Order 13132 (64 FR 43255, August 
10, 1999). This action also is not subject to Executive Order 13045 (62 
FR 19885, April 23, 1997), because it is not economically significant.
    This action does not involve technical standards; thus, the 
requirements of section 12(d) of the National Technology Transfer and 
Advancement Act of 1995 (15 U.S.C. 272 note) do not apply. This rule 
does not impose an information collection burden under the provisions 
of the Paperwork Reduction Act of 1995 (44 U.S.C. 3501 et seq.).
    Section 7 of the Endangered Species Act (16 U.S.C. 1656 et seq.), 
requires Federal agencies, in consultation with the U.S. Fish and 
Wildlife Service and National Marine Fisheries Service, to ensure that 
their actions are unlikely to jeopardize the continued existence of 
listed species or adversely affect designated critical habitat of such 
species. EPA intends to fulfill any applicable ESA requirements prior 
to final withdrawal of the Federal nutrient standards for Arizona. 
(None of the Arizona waters affected by this proposed rule has species 
or habitats within the jurisdiction of National Marine Fisheries 
Service.)

List of Subjects in 40 CFR Part 131

    Indians-lands, Intergovernmental relations, Reporting and 
recordkeeping requirements, Water pollution control.

    Dated: July 24, 2001.
Christine Todd Whitman,
Administrator.
    For the reasons set out in the preamble, Part 131 of title 40, 
chapter I of the Code of Federal Regulations is proposed to be amended 
as follows:

PART 131--WATER QUALITY STANDARDS

    1. The authority citation for Part 131 continues to read as 
follows:

    Authority: 33 U.S.C. 1251 et seq.


Sec. 131.31  [Amended]

    2. Section 131.31 is amended by removing and reserving paragraph 
(a).

[FR Doc. 01-18886 Filed 7-27-01; 8:45 am]
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