WSP03524

• File Number: 8273.500
• Description: Colorado River Basin Salinity Control - Federal Agencies - EPA
• Basin: Colorado Mainstem
• Water Division: 5
• Date: 11/8/1983
• Title: Federal Register - Environmental Protection Agency Part II
• Water Supply Pro - Doc Type: Publication

Federal Register / Vol. 48, No, .217 / Tuesday, November 8, 1983 I Rules and Regula~ons 51~:il

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technological, soci,al, economic. and
institutional factota.. in determining the
attainability of staj1dards for any
particular. water'a'egment. In add.itio'n..
there is and has bEfen an economic
consideration in th~ antidegrade.tion
policy. The Agency recognizes that there.
are-inherent difficulties in a balancing of
the henefits of achieving the Section
101(a)(2) goals of the Act with the co.ts,
As 8 result, the Agency'was persuaded
that the provision in the existing rule
a!towing ch.nge. ill deaignated u.e.
where there would pe .ub.tantial and
widespread ecoDontlc impact beUer
reflected the proce~srequirad by the
Act. For these reasons, the wording of
the existing regulation has "been
retained.

Several commenters objected to
propo.ed ~ 131.10(h)(5) which a!towed
States to remove or~to modify
designs ted uses which are not
attainable ba.ed on!phy.ical factors.
After considering the comments, the
Ag.ncy d.cid.d to limit. the ref.rence to
phy.ical factor. to aqua tic life
protection uses and,to clarify the
existing policy.
Phy.ical factQr. n(ay b. important in
evaluating whether ~es are attainable.
How.ver, physicallihiitation. of the
stream may riot neGfissarily be an
overriding factor. Common sense and
good judgment play an Important 1'01. in
setting appropriate u~es and criteria. In
setting criteria and uses, States -must
assure the attainment of downstream
standards. 'The dOW~$tre8m uses,-may
.not be affected by th$ ..am. physical
. limitations ,as the up~tream uses_. There
ar~ instan.ces where ~'6n.Hwater quality
related factors preclu,de tbe ~ttainment
of uses regardless of ~mprovemen ts in
water quality. This isiparticularly'true
for fish and wjldlif~ protection uses
where the lack of a proper substrate
may preclude certain'f6rms of aquatic
life from using the str~8m for
propagation, or the lack of "over. depth,
flow, pools, riffles or i,mp8.cts from .
ch8n~elization, dams,; divers,ions may
preclude particular forms of a.quatic life
from the .tream altogather. EPA
recognizes tJIat while physical faCtors
also affect the l'ecreaHonal uses
appropriately designated for a water
body. States need to ~ive consideration
to the incidental uses ~hich may be ,
made of the water body. Even though it
may not make sense to encourage use of
a stream for swimming because of the
flow, depth or th~ velopity of th. water,
the State. and EPA m~.t recognize that
swimming and/or wading may occur
anyway. In order to protect public
health, States must sei'criteria. to reflect
re'creational uses iqt appears that

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recreation will in fact occur in the
stream,.
In keeping with the purpose. of the
Act, the wording Qf ~ 131,10(h)(4) of the
propo.ed'Rule (now ~'131,10(g)(4)) was
modified .0 that change. in u.e. CQuld
only occur if darns. diversions or other
types of hydrologic modifications
Pl'eclude rather than just interfere with
the attainment of the de.ignat.d use., It
.hould al.o be pointed oui that if
physical limitation. of the water boay
were u.ed a. the ba.i. of not including
u.e. for a water body that are .pecified
in Section 101(a){2) of the Act, tho.e
physical factors must be reviewed every
three years.
'While many commenters objected to
the number of reasons the States could
use in justifying changes in uses, the
Agency decided to keep the .ix factor.,
with the changes.de.cribed above,
because they bette:r explain when
change. may be made. Th. ter.e
wording of the existing Rule doe. not
adequately explain when changes can
be made. .
A number of comments related to use
attainability analyses. In demonstrating
that a u.e i. not attainable, State. will
be required to prepare and submit to .
EPA a use attainability analysis. A use
attainability analysis is a multi-step
sci.ntific a.se..mant of the phy.ical,
chemical, biological and economic
factor. affecting the attainment of a u.e.
It includes a-water body ,s-urvey and .
assessment, a wasteload allocation. and
an economic analysis, if appropriate.
A water body survey and assessment
examines the physical, chemical and
biological characteristics _of the water
body to: identify and define the exi.ting
uses of that water body; determine
whether the designat.d u.es in the State
water quality standards are impaired.
and the reasons for' the impairmentj and
assist.8tates in projecting the potential
u.es that the water body could .upport
in the absence of pollution. A waf!teload
allo~Btion utilizes mathematical models
to predict the amount of reduction
necessary in poUutant loadings to
achieve the designated use. Economic
, analyses are appropriate'in determining
whether th~, more stringent requirements
would _cause substantial and
widespread economic and social impact.
The.e analy.e. .houid addre.. the
incremental effects of water quality
.tandard. beyond technology-ba.ed or
otherState requir.ment.. The Agency'.
guidance suggests that States consider
effects due to compliance by private and'
municipal dischargers. If the
requirements are not demonstrated to
have a substantial and widespread
impact on the affected community, the

.landard mU&t be maintained or made
compatible with the goallf~of the 'Ad!.'
There was considerable' comment'on
wh.ther the use attaioobllity analy....
. .hould be required, and itso when. In
keeping with ~ection 510 of the Act.llPA .,
is not requiring State. to conduct and' '
submit a use attainabilityi'analysfs if '
, adding a use specified in S,ectiqn '
101(a)(2) of the Act 01' a u.e requiring
more stringent criteria-. In the final rule.
EPA i. requiring that States conduct and
.ubmitto EPA a u.e attainabilitr
analy.i. if the State (a) i. designating
u.e. for the water body .u,h that the
wa tel' body will not have sll u.e. which
are includ.d in Section 10l(aJ(2) of the
Act, (b) maintaining u.e. for the water
body which do not include all of the
u... in Section 101(a)(2) of the Act: (c)
removing a use ineluded in'S~ction
101(a)(2) of the Act or (d) modifying a
use included in Section101(a)(2)ofthe
Act to require less stringent OrUe'ria. A
State need only conduct a u.e
attainability once for a given water
body and .et of u.e.. During .ub..quent
triennial review, State. will be required
to review the basis of not i:q,cJud~ng,;uses
for the water body that are,.pecified in
Section 101(a)(2) of the Act'to .how thai
cirCun'lstances ,have not ch~.nged 'I;lnd
that prate. ction and propa~a. tion of.fi.h,
shellfi.h and wildlife and/or recreation
in and -on the water remain
unattainable. If such u.e. h..ve become
attainable. the .tandard mu.t be revi.ed
accordingly (Se. ~131.20(aJJ, However,
State. may wi.h to conduct'll u.e
attainability -analysis. even where not
required. if they believe thattherewill
be que.tion. a. to wh.ther the
protection and prOpagatioll offi.h,
.hellfi.h and wildlife and.recreationin
--Bnd on th'e _water is, in fact, attain~b_le.
The guidance on conducting the' wa:ter
body survey and- assessment: is i,neluded
in the Water QiJo/ity Stondard.
Handbook. The aarlier draft of the .
Handbook has been revjsed :apd)
expanded. T..t ca... illustrating the
-water body survey and assessment
guidance have been completed and are
included in the Handbook. In. addition,
the Agency has publi.hed a Technical
Support Manual: Water Body Surveys
and Assessments for Conducting G' Use
AttainabJ1ity Analyses, Th..~
publication. may' be obtainedhy writing
or calling David K. Sabock atthe
addre.s and phone number li$t.d under
FOR FURTHER INFORMATION CONTACT.
By publishing guidance on .conducting
u.e attainability analy.e., EPA is not
requiring_ that'specific approaches.
method. or procedures be u..d, Rather,
States ara en\iPuraged to conSult with
EP A early in the proees~ to ag~ee on .

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