COLORADO DEPARTMENT OF PUBLIC HEALTH AND ENVIRONMENT 
WATER QUALITY CONTROL COMMISSION 
5 CCR 1002-32 
REGULATION NO. 32 
CLASSIFICATIONS AND NUMERIC STANDARDS 
FOR 
ARKANSAS RIVER BASIN
. . . .
32.6 	TABLES
. . . .
(2)	Abbreviations:
. . . .
(d)	Temporary Modification for Water + Fish Chronic Arsenic Standard
(i)	The temporary modification for chronic arsenic standards applied to segments with an arsenic standard of 0.02 mg/l that has been set to protect the Water+Fish qualifier is listed in the temporary modification and qualifiers column as As(ch)=hybrid.
(ii)	For discharges existing on or before 6/1/2013, the temporary modification is:  As(ch)=current condition, expiring on 12/31/2021.
(iii)	For new or increased discharges commencing on or after 6/1/2013, the temporary modification is:  As(ch)=0.02-3.0 mg/l (Trec), expiring on 12/31/2021.
(a)	The first number in the range is the health-based water quality standard previously adopted by the Commission for the segment.
(b)	The second number in the range is a technology based value established by the Commission for the purpose of this temporary modification.
(c)	Control requirements, such as discharge permit effluent limitations, shall be established using the first number in the range as the ambient water quality target, provided that no effluent limitation shall require an “end-of-pipe” discharge level more restrictive than the second number in the range.
(3)	Table Value Standards
. . . .

REGION: 13

BASIN: UPPER ARKANSAS RIVER	
Desig	
Classifications	
NUMERIC STANDARDS	TEMPORARY
MODIFICATIONS
AND
QUALIFIERS	

	PHYSICAL
and
BIOLOGICAL	INORGANIC
mg/l	METALS
ug/l		

Stream Segment Description							

1b.	Mainstem of the East Fork of the Arkansas River from its source to a point immediately above the confluence with Birdseye Gulch.	
	
Aq Life Cold 1
Recreation E
Water Supply	
D.O. = 6.0 mg/l
D.O. (sp)=7.0 mg/l
pH = 6.5-9.0
E.Coli=126/100ml	
NH3(ac/ch)=TVS
CL2(ac)=0.019
CL2(ch)=0.011
CN=0.005	
S=0.002
NO2=0.05
NO3=10
Cl=250
SO4=WS	
As(ac)=340
As(ch)=0.02(Trec)
Cd(ac)=TVS(tr)
Cd(ch)=TVS
CrIII(ac)=50(Trec)
CrVI(ac/ch)=TVS
Cu(ac/ch)=TVS	
Fe(ch)=WS(dis)
Fe(ch)=1000(Trec)
Pb(ac/ch)=TVS
Mn(ac/ch)=TVS
Mn(ch)=WS(dis)	
Hg(ch)=0.01(tot)
Ni(ac/ch)=TVS
Se(ac/ch)=TVS
Ag(ac)=TVS
Ag(ch)=TVS(tr)
Zn(ch)=TVS
Zn(ac)=150	
Temporary modification:
As(ch)=hybrid
Expiration date of 12/31/21.	

3.	Mainstem of the Arkansas River from a point immediately above the confluence with the Lake Creek to the inlet to Pueblo Reservoir.	
	
Aq Life Cold 1
Recreation E
Water Supply
Agriculture	
D.O. = 6.0 mg/l
D.O. (sp)=7.0 mg/l
pH = 6.5-9.0
E.Coli=126/100ml	
NH3(ac/ch)=TVS
CL2(ac)=0.019
CL2(ch)=0.011
CN=0.005
S=0.002	
B=0.75
NO2=0.05
NO3=10
Cl=250
SO4=WS	
As(ac)=340
As(ch)=0.02(Trec)
Cd(ac)=TVS(tr)
Cd(ch)=TVS
CrIII(ac)=50(Trec)
CrVI(ac/ch)=TVS
Cu(ac/ch)=TVS	
Fe(ch)=WS(dis)
Fe(ch)=1000(Trec)
Pb(ac/ch)=TVS
Mn(ac/ch)=TVS
Mn(ch)=WS(dis)	
Hg(ch)=0.01(tot)
Ni(ac/ch)=TVS Se(ac/ch)=TVS
Ag(ac)=TVS
Ag(ch)=TVS(tr)
Zn(ac/ch)=TVS	
Temporary modifications:
Type (iii)
Cd(ch)=0.48
Expiration date of 12/31/13.

As(ch)=hybrid
Expiration date of 12/31/21.	

5.	All tributaries to the Arkansas River, including wetlands, lakes and reservoirs, from the source to immediately below the confluence with Browns Creeks, except for specific listings in segments 6 through 12.	
	
Aq Life Cold 1
Recreation E
Water Supply
Agriculture	
D.O. = 6.0 mg/l
D.O. (sp)=7.0 mg/l
pH = 6.5-9.0
E.Coli=126/100ml	
NH3(ac/ch)=TVS
CL2(ac)=0.019
CL2(ch)=0.011
CN=0.005
S=0.002	
B=0.75
NO2=0.05
NO3=10
Cl=250
SO4=WS	
As(ac)=340
As(ch)=0.02(Trec)
Cd(ac)=TVS(tr)
Cd(ch)=TVS
CrIII(ac)=50(Trec)
CrVI(ac/ch)=TVS
Cu(ac/ch)=TVS	
Fe(ch)=WS(dis)
Fe(ch)=1000(Trec)
Pb(ac/ch)=TVS
Mn(ac/ch)=TVS
Mn(ch)=WS(dis) 	
Hg(ch)=0.01(tot)
Ni(ac/ch)=TVS
Se(ac/ch)=TVS
Ag(ac)=TVS
Ag(ch)=TVS(tr)
Zn(ac/ch)=TVS	
Temporary modification:
As(ch)=hybrid
Expiration date of 12/31/21.	

12a	Mainstem of Chalk Creek from the source to the confluence with the Arkansas River.		
Aq Life Cold 1
Recreation E
Water Supply
Agriculture	
D.O.=6.0 mg/l
D.O.(sp)=7.0 mg/l
pH=6.5-9.0
E.Coli=126/100ml	
NH3(ac/ch)=TVS
CL2(ac)=0.019
CL2(ch)=0.011
CN=0.005
S=0.002	
B=0.75
NO2=0.05
NO3=10
Cl=250
SO4=WS	
As(ac)=340
As(ch)=0.02(Trec)
Cd(ac)=TVS(tr)
Cd(ch)=TVS
CrIII(ac)=50(Trec)
CrVI(ac/ch)=TVS
Cu(ac/ch)=TVS	
Fe(ch)=WS(dis)
Fe(ch)=1000(Trec)
Pb(ac/ch)=TVS
Mn(ch)=WS(dis)
Mn(ac/ch)=TVS
Hg(ch)=0.01(tot)	
Ni(ac/ch)=TVS
Se(ac/ch)=TVS
Ag(ac)=TVS
Ag(ch)=TVS(tr)
Zn(ac/ch)=TVS	
Temporary modification
(type i):
Zn(ch)=120
Expiration date of 12/31/2013.

 As(ch)=hybrid
Expiration date of 12/31/21.	

12b.	Mainstem of Cottonwood Creek (Chaffee County), from the source to the confluence with the Arkansas River; South Fork of the Arkansas including all tributaries, wetlands, lakes and reservoirs, from the source to the confluence with the Arkansas River.		
Aq Life Cold 1
Recreation E
Water Supply
Agriculture
	
D.O.=6.0 mg/l
D.O.(sp)=7.0 mg/l
pH=6.5-9.0
E.Coli=126/100ml
	
NH3(ac/ch)=TVS
CL2(ac)=0.019
CL2(ch)=0.011
CN=0.005
S=0.002
B=0.75	
NO2=0.05
NO3=10
Cl=250
SO4=WS	As(ac)=340
As(ch)=0.02(Trec)
Cd(ac)=TVS(tr)
Cd(ch)=TVS
CrIII(ac)=50(Trec)
CrVI(ac/ch)=TVS
Cu(ac/ch)=TVS	
Fe(ch)=WS(dis)
Fe(ch)=1000(Trec)
Pb(ac/ch)=TVS
Mn(ac/ch)=TVS
Mn(ch)=WS(dis)	
Hg(ch)=0.01(tot)
Ni(ac/ch)=TVS
Se(ac/ch)=TVS
Ag(ac)=TVS
Ag(ch)=TVS(tr)
Zn(ac/ch)=TVS	
Temporary modification:
As(ch)=hybrid
Expiration date of 12/31/21.	

13.	All tributaries to the Arkansas River, including wetlands, lakes and reservoirs, which are on National Forest lands, from the confluence with Brown's Creek to the inlet to Pueblo Reservoir, except for specific listings in segments 12 and 15-27.	
		
Aq Life Cold 1
Recreation E
Water Supply
Agriculture
	
D.O.=6.0 mg/l
D.O.(sp)=7.0 mg/l
pH=6.5-9.0
E.Coli=126/100ml	
NH3(ac/ch)=TVS
CL2(ac)=0.019
CL2(ch)=0.011
CN=0.005
S=0.002	
B=0.75
NO2=0.05
NO3=10
Cl=250
SO4=WS	
As(ac)=340
As(ch)=0.02(Trec)
Cd(ac)=TVS(tr)
Cd(ch)=TVS
CrIII(ac)=50(Trec)
CrVI(ac/ch)=TVS
Cu(ac/ch)=TVS	
Fe(ch)=WS(dis)
Fe(ch)=1000(Trec)
Pb(ac/ch)=TVS
Mn(ac/ch)=TVS
Mn(ch)=WS(dis) 	
Hg(ch)=0.01(tot)
Ni(ac/ch)=TVS
Se(ac/ch)=TVS
Ag(ac)=TVS
Ag(ch)=TVS(tr)
Zn(ac/ch)=TVS	
Temporary modification:
As(ch)=hybrid
Expiration date of 12/31/21.	

15.	Mainstem of Grape Creek from the source to the outlet of De Weese Reservoir; mainstems of Texas, Badger, Hayden, Hamilton, Stout, and Big Cottonwood Creeks, including all tributaries, wetlands, lakes and reservoirs, from their sources to their confluences with the Arkansas River.  Mainstem of Newlin Creek from the National Forest boundary to the City of Florence water diversion.	
	
Aq Life Cold 1
Recreation E
Water Supply
Agriculture
	
D.O.=6.0 mg/l
D.O.(sp)=7.0 mg/l
pH=6.5-9.0
E.Coli=126/100ml
	
NH3(ac/ch)=TVS
CL2(ac)=0.019
CL2(ch)=0.011
CN=0.005
S=0.002	
B=0.75
NO2=0.05
NO3=10
Cl=250
SO4=WS 	
As(ac)=340
As(ch)=0.02(Trec)
Cd(ac)=TVS(tr)
Cd(ch)=TVS
CrIII(ac)=50(Trec)
CrVI(ac/ch)=TVS
Cu(ac/ch)=TVS	
Fe(ch)=WS(dis)
Fe(ch)=1000(Trec)
Pb(ac/ch)=TVS
Mn(ac/ch)=TVS
Mn(ch)=WS(dis)	
Hg(ch)=0.01(tot)
Ni(ac/ch)=TVS
Se(ac/ch)=TVS
Ag(ac)=TVS
Ag(ch)=TVS(tr)
Zn(ac/ch)=TVS	
Temporary modification:
As(ch)=hybrid
Expiration date of 12/31/21.	

Region: 13

BASIN: UPPER ARKANSAS RIVER	
Desig	
Classifications	
NUMERIC STANDARDS	
TEMPORARY
MODIFICATIONS
AND
QUALIFIERS	

	PHYSICAL
and
BIOLOGICAL	INORGANIC
mg/l	METALS
ug/l		

Stream Segment Description							

16c.	Mainstem of Tallahassee Creek from a point immediately below the confluence with South Tallahassee Creek to the confluence with the Arkansas River.	
	
Aq Life Cold 1
Recreation E
Water Supply
Agriculture	
D.O.=6.0 mg/l
D.O.(sp)=7.0 mg/l
pH=6.5-9.0
E.Coli=126/100ml
	
NH3(ac/ch)=TVS
CL2(ac)=0.019
CL2(ch)=0.011
CN=0.005
S=0.002	
B=0.75
NO2=0.05
NO3=10
Cl=250
SO4=WS	
As(ac)=340
As(ch)=0.02(Trec)
Cd(ac)=TVS(tr)
Cd(ch)=TVS
CrIII(ac)=50(Trec)
CrVI(ac/ch)=TVS
Cu(ac/ch)=TVS	
Fe(ch)=WS(dis)
Fe(ch)=1000(Trec)
Pb(ac/ch)=TVS
Mn(ac/ch)=TVS
Mn(ch)=WS(dis)
Hg(ch)=0.01(tot)	
Ni(ac/ch)=TVS
Se(ac/ch)=TVS
Ag(ac)=TVS
Ag(ch)=TVS(tr)
Zn(ac/ch)=TVS	
Temporary modification:
As(ch)=hybrid
Expiration date of 12/31/21.	

17a.	Mainstem of Cottonwood Creek (Fremont County) including all tributaries, wetlands, lakes and reservoirs, from the source to a point immediately below the confluence with North Waugh Creek.	
	
Aq Life Cold 1
Recreation E
Water Supply
Agriculture	
D.O. = 6.0 mg/l
D.O. (sp)=7.0 mg/l
pH = 6.5-9.0
E.Coli=126/100ml	
NH3(ac/ch)=TVS
CL2(ac)=0.019
CL2(ch)=0.011
CN=0.005	
S=0.002
B=0.75
NO2=0.05
NO3=10
Cl=250
SO4=WS	
As(ac)=340
As(ch)=0.02(Trec)
Cd(ac)=TVS(tr)
Cd(ch)=TVS
CrIII(ac)=50(Trec)
CrVI(ac/ch)=TVS
Cu(ac/ch)=TVS	
Fe(ch)=WS(dis)
Fe(ch)=1000(Trec)
Pb(ac/ch)=TVS
Mn(ac/ch)=TVS
Mn(ch)=WS(dis)	
Hg(ch)=0.01(tot)
Ni(ac/ch)=TVS
Se(ac/ch)=TVS
Ag(ac)=TVS
Ag(ch)=TVS(tr)
Zn(ac/ch)=TVS	
Temporary modification:
As(ch)=hybrid
Expiration date of 12/31/21.	

19.	Mainstem of Fourmile Creek, including all tributaries, wetlands, lakes and reservoirs, from the source to immediately above the confluence with Cripple Creek.		

Aq Life Cold 1
Recreation E
Water Supply
Agriculture

D.O. = 6.0 mg/l
D.O. (sp)=7.0 mg/l
pH = 6.5-9.0
E.Coli=126/100ml

NH3(ac/ch)=TVS
CL2(ac)=0.019
CL2(ch)=0.011
CN=0.005
S=0.002	

B=0.75
NO2=0.5
NO3=10
Cl=250
SO4=WS	

As(ac)=340
As(ch)=0.02(Trec)
Cd(ac)=TVS(tr)
Cd(ch)=TVS
CrIII(ac)=50(Trec)
CrVI(ac/ch)=TVS
Cu(ac/ch)=TVS	

Fe(ch)=WS(dis)
Fe(ch)=1000(Trec)
Pb(ac/ch)=TVS
Mn(ac/ch)=TVS	

Hg(ch)=0.01(tot)
Ni(ac/ch)=TVS
Se(ac/ch)=TVS
Ag(ac)=TVS
Ag(ch)=TVS(tr)
Zn(ac/ch)=TVS	

Temporary modification:
As(ch)=hybrid
Expiration date of 12/31/21.	

20.	Mainstem of Fourmile Creek, including all tributaries, wetlands, lakes and reservoirs, from immediately above the confluence with Cripple Creek to the confluence with the Arkansas River, except for the specific listing to segment 23.		
Aq Life Cold 1
Recreation E
Agriculture
Water Supply	
D.O. = 6.0 mg/l
D.O. (sp)=7.0 mg/l
pH = 6.5-9.0
E.Coli=126/100ml	
NH3(ac/ch)=TVS
CL2(ac)=0.019
CL2(ch)=0.011	
CN=0.005
S=0.002
B=0.75
NO2=.05 
SO4=WS	
As(ac)=340
As(ch)=0.02(Trec)
Cd(ac)=TVS(tr)
Cd(ch)=TVS
CrIII(ch)=100(Trec)
CrVI(ac/ch)=TVS
Cu(ac/ch)=TVS	
Fe(ch)=WS(dis)
Fe(ch)=1000(Trec)
Pb(ac/ch)=TVS
Mn(ac/ch)=TVS
Mn(ch)=WS(dis)*	
Hg(ch)=0.01(tot)
Ni(ac/ch)=TVS
Se(ac/ch)=TVS
Ag(ac)=TVS
Ag(ch)=TVS(tr)
Zn(ac/ch)=TVS	

Temporary modification:
As(ch)=hybrid
Expiration date of 12/31/21.	
*Dissolved Mn and SO4 standards applicable at the point of withdraw.

24.	Mainstem of East and West Beaver Creeks, including all tributaries, wetlands, lakes and reservoirs, from the source to the confluence with Beaver Creek; mainstem of Beaver Creek from the source to the point of diversion to Brush Hollow Reservoir.	
	
Aq Life Cold 1
Recreation E
Water Supply
Agriculture
	
D.O.=6.0 mg/l
D.O.(sp)=7.0 mg/l
pH=6.5-9.0
E.Coli=126/100ml
	
NH3(ac/ch)=TVS
CL2(ac)=0.019
CL2(ch)=0.011
CN=0.005
S=0.002	
B=0.75
NO2=0.05
NO3=10
Cl=250
SO4=WS	
As(ac)=340
As(ch)=0.02(Trec)
Cd(ac)=TVS(tr)
Cd(ch)=TVS
CrIII(ac)=50(Trec)
CrVI(ac/ch)=TVS
Cu(ac/ch)=TVS	
Fe(ch)=WS(dis)
Fe(ch)=1000(Trec)
Pb(ac/ch)=TVS
Mn(ac/ch)=TVS
Mn(ch)=WS(dis)	
Hg(ch)=0.01(tot)
Ni(ac/ch)=TVS
Se(ac/ch)=TVS
Ag(ac)=TVS
Ag(ch)=TVS(tr)
Zn(ac/ch)=TVS	
Temporary modification:
As(ch)=hybrid
Expiration date of 12/31/21.	

REGION: 7

BASIN: MIDDLE ARKANSAS RIVER 	
Desig	
Classifications	
NUMERIC STANDARDS	
TEMPORARY
MODIFICATIONS
AND
QUALIFIERS	

	PHYSICAL
and
BIOLOGICAL
	INORGANIC
mg/l	METALS
ug/l		

Stream Segment Description							

2.	Mainstem of the Arkansas River from the outlet of Pueblo Reservoir to a point immediately above the confluence with Wildhorse/Dry Creek Arroyo.	
	
Aq Life Cold 1
Water Supply
Agriculture
	
D.O. = 6.0 mg/l
D.O. (sp)=7.0 mg/l
pH = 6.5-9.0 
E.Coli=126/100ml
	
NH3(ac/ch)=TVS
CL2(ac)=0.019
CL2(ch)=0.011
CN=0.005
S=0.002	
B=0.75
NO2=0.05
NO3=10
Cl=250 
SO4=WS	
As(ac)=340
As(ch)=0.02(Trec)
Cd(ac)=TVS(tr)
Cd(ch)=TVS
CrIII(ac)=50(Trec)
CrVI(ac/ch)=TVS
Cu(ac/ch)=TVS	
Fe(ch)=WS(dis)
Fe(ch)=1000(Trec)
Pb(ac/ch)=TVS
Mn(ac/ch)=TVS
Mn(ch)=WS(dis)	
Hg(ch)=0.01(tot)
Ni(ac/ch)=TVS
Se(ac/ch)=TVS
Ag(ac)=TVS
Ag(ch)=TVS(tr)
Zn(ac/ch)=TVS	
Temporary modification:
As(ch)=hybrid
Expiration date of 12/31/21.

3.	Mainstem of the Arkansas River from a point immediately above the confluence with Wildhorse/Dry Creek Arroyo to a point immediately above the confluence with Fountain Creek, Valco Ponds and Fountain Lake.	
	
Aq Life Warm 1
Recreation E
Water Supply
Agriculture	
D.O. = 5.0 mg/l
pH = 6.5-9.0
E.Coli=126/100ml
	
NH3(ac/ch)=TVS
CL2(ac)=0.019
CL2(ch)=0.011
CN=0.005
S=0.002	
B=0.75
NO2=0.05
NO3=10
Cl=250
SO4=WS	
As(ac)=340
As(ch)=0.02(Trec)
Cd(ac/ch)=TVS
CrIII(ac)=TVS(Trec)
CrVI(ac/ch)=TVS
Cu(ac/ch)=TVS	
Fe(ch)=WS(dis)
Fe(ch)=1000(Trec)
Pb(ac/ch)=TVS
Mn(ac/ch)=TVS
Mn(ch)=WS(dis)	
Hg(ch)=0.01(tot)
Ni(ac/ch)=TVS
Se(ac)=50.9
Se(ch)=17.4
Ag(ac)=TVS
Ag(ch)=TVS(tr)
Zn(ac/ch)=TVS	
Temporary modification:
As(ch)=hybrid
Expiration date of 12/31/21.	

5.	Mainstem of the Saint Charles River, including all tributaries, wetlands, lakes and reservoirs, from the source to a point immediately above the CF&I diversion canal near Burnt Mill.	
UP	
Aq Life Cold 1
Recreation E
Water Supply
Agriculture	
D.O. = 6.0 mg/l
D.O. (sp)=7.0 mg/l
pH = 6.5-9.0
E.Coli=126/100ml
	
NH3(ac/ch)=TVS
CL2(ac)=0.019
CL2(ch)=0.011
CN=0.005
S=0.002	
B=0.75
NO2=0.05
NO3=10
Cl=250
SO4=WS	
As(ac)=340
As(ch)=0.02(Trec)
Cd(ac)=TVS(tr)
Cd(ch)=TVS
CrIII(ac)=50(Trec)
CrVI(ac/ch)=TVS
Cu(ac/ch)=TVS	
Fe(ch)=WS(dis)
Fe(ch)=1000(Trec)
Pb(ac/ch)=TVS
Mn(ac/ch)=TVS
Mn(ch)=WS(dis)	
Hg(ch)=0.01(tot)
Ni(ac/ch)=TVS
Se(ac/ch)=TVS
Ag(ac)=TVS
Ag(ch)=TVS(tr)
Zn(ac/ch)=TVS	

As(ch)=hybrid
Expiration date of 12/31/21.	

7.	Mainstem of the Greenhorn Creek, including all tributaries, wetlands, lakes and reservoirs from the source to a point immediately below the Greenhorn Highline (Hayden Supply Ditch) diversion dam, except for specific listings in segment 8; mainstem of Graneros Creek; mainstem of North Muddy Creek.	
	
Aq Life Cold 1
Recreation E
Water Supply
Agriculture	
D.O. = 6.0 mg/l
D.O. (sp)=7.0 mg/l
pH = 6.5-9.0
E.Coli=126/100ml
	
NH3(ac/ch)=TVS
CL2(ac)=0.019
CL2(ch)=0.011
CN=0.005
S=0.002	
B=0.75
NO2=0.05
NO3=10
Cl=250
SO4=WS	
As(ac)=340
As(ch)=0.02(Trec)
Cd(ac)=TVS(tr)
Cd(ch)=TVS
CrIII(ac)=50(Trec)
CrVI(ac/ch)=TVS
Cu(ac/ch)=TVS	
Fe(ch)=WS(dis)
Fe(ch)=1000(Trec)
Pb(ac/ch)=TVS
Mn(ac/ch)=TVS
Mn(ch)=WS(dis)	
Hg(ch)=0.01(tot)
Ni(ac/ch)=TVS
Se(ac/ch)=TVS
Ag(ac)=TVS
Ag(ch)=TVS(tr)
Zn(ac/ch)=TVS	
Temporary modification:
As(ch)=hybrid
Expiration date of 12/31/21.

9.	Mainstem of Greenhorn Creek, from a point immediately below the Greenhorn Highline (Hayden Supply Ditch) diversion dam, to the confluence with the Saint Charles River.	
UP	
Aq Life Warm 2
Recreation E
Water Supply
Agriculture	
D.O. = 5.0 mg/l
pH = 6.5-9.0
E.Coli=126/100ml
	
NH3(ac/ch)=TVS
CL2(ac)=0.019
CL2(ch)=0.011
CN=0.005
S=0.002	
B=0.75
NO2=0.5
NO3=10
Cl=250
SO4=700 
	
As(ac)=340
As(ch)=0.02(Trec)
Cd(ac/ch)=TVS
CrIII(ac)=50(Trec)
CrVI(ac/ch)=TVS
Cu(ac/ch)=TVS	
Fe(ch)=WS(dis)
Fe(ch)=1000(Trec)
Pb(ac/ch)=TVS
Mn(ac/ch)=TVS
Mn(ch)=WS(dis)	
Hg(ch)=0.01(tot)
Ni(ac/ch)=TVS
Se(ac/ch)=TVS
Ag(ac)=TVS
Ag(ch)=TVS(tr)
Zn(ac/ch)=TVS	Temporary modifications: 
type (iii)
Se(ch)=8.6.
Expiration date of 12/31/2013.

As(ch)=hybrid
Expiration date of 12/31/21.

11.	Mainstem of the Huerfano River including all tributaries, wetlands, lakes and reservoirs from the source to the confluence with Muddy Creek near Gardner; mainstem of Turkey Creek (in Huerfano County) from the source to confluence with the Huerfano River.	
	
Aq Life Cold 1
Recreation E
Water Supply
Agriculture	
D.O. = 6.0 mg/l
D.O.(sp)=7.0 mg/l
pH = 6.5-9.0
E.Coli=126/100ml
	
NH3(ac/ch)=TVS
CL2(ac)=0.019
CL2(ch)=0.011
CN=0.005
S=0.002	
B=0.75
NO2=0.05
NO3=10
Cl=250
SO4=WS	
As(ac)=340
As(ch)=0.02(Trec)
Cd(ac)=TVS(tr)
Cd(ch)=TVS
CrIII(ac)=50(Trec)
CrVI(ac/ch)=TVS
Cu(ac/ch)=TVS	
Fe(ch)=WS(dis)
Fe(ch)=1000(Trec)
Pb(ac/ch)=TVS
Mn(ac/ch)=TVS
Mn(ch)=WS(dis)	
Hg(ch)=0.01(tot)
Ni(ac/ch)=TVS
Se(ac/ch)=TVS
Ag(ac)=TVS
Ag(ch)=TVS(tr)
Zn(ac/ch)=TVS	
Temporary modification:
As(ch)=hybrid
Expiration date of 12/31/21.

13.	Mainstem of the Cucharas River, including all tributaries, wetlands, lakes and reservoirs, from the source to the point of diversion for the Walsenburg public water supply	
	
Aq Life Cold 1
Recreation E
Water Supply
Agriculture	
D.O. = 6.0 mg/l
D.O.(sp)=7.0 mg/l
pH = 6.5-9.0
E.Coli=126/100ml
	
NH3(ac/ch)=TVS
CL2(ac)=0.019
CL2(ch)=0.011
CN=0.005
S=0.002	
B=0.75
NO2=0.05
NO3=10
Cl=250
SO4=WS	
As(ac)=340
As(ch)=0.02(Trec)
Cd(ac)=TVS(tr)
Cd(ch)=TVS
CrIII(ac)=50(Trec)
CrVI(ac/ch)=TVS
Cu(ac/ch)=TVS
	
Fe(ch)=WS(dis)
Fe(ch)=1000(Trec)
Pb(ac/ch)=TVS
Mn(ac/ch)=TVS
Mn(ch)=WS(dis)	
Hg(ch)=0.01(tot)
Ni(ac/ch)=TVS
    Se(ac/ch)=TVS
Ag(ac)=TVS
Ag(ch)=TVS(tr)
Zn(ac/ch)=TVS	
Temporary modification:
As(ch)=hybrid
Expiration date of 12/31/21.

REGION: 7

BASIN: MIDDLE ARKANSAS RIVER 	
Desig	
Classifications	
NUMERIC STANDARDS	
TEMPORARY
MODIFICATIONS
AND
QUALIFIERS	

	PHYSICAL
and
BIOLOGICAL
	INORGANIC
mg/l	METALS
ug/l		

Stream Segment Description							

17.	Mainstem of the South Apache Creek from the source to the boundary of BLM lands, in Section 25, T25S, R68W; mainstem of North Apache Creek from the source to the southern boundary of Section 24, T25S, R68W.	
	
Aq Life Cold 1
Recreation E
Water Supply
Agriculture	
D.O. = 6.0 mg/l
D.O. (sp)=7.0 mg/l
pH = 6.5-9.0
E.Coli=126/100ml
	
NH3(ac/ch)=TVS
CL2(ac)=0.019
CL2(ch)=0.011
CN=0.005
S=0.002	
B=0.75
NO2=0.05
NO3=10
Cl=250
SO4=WS	
As(ac)=340
As(ch)=0.02(Trec)
Cd(ac)=TVS(tr)
Cd(ch)=TVS
CrIII(ac)=50(Trec)
CrVI(ac/ch)=TVS
Cu(ac/ch)=TVS	
Fe(ch)=WS(dis)
Fe(ch)=1000(Trec)
Pb(ac/ch)=TVS
Mn(ac/ch)=TVS
Mn(ch)=WS(dis)	
Hg(ch)=0.01(tot)
Ni(ac/ch)=TVS
Se(ac/ch)=TVS
Ag(ac)=TVS
Ag(ch)=TVS(tr)
Zn(ac/ch)=TVS	
Temporary modification:
As(ch)=hybrid
Expiration date of 12/31/21.

18b.	Turkey Creek (Pueblo County) from U.S. Highway 50 to Pueblo Reservoir; unnamed tributary to Arkansas River, located in Section 33, Township 20 South, Range 65 West; mainstem of Rush Creek (Pueblo County) from the source to the confluence with the Arkansas River.	
	
Aq Life Warm 1
Recreation E
Water Supply
Agriculture
	
D.O.=5.0 mg/l
pH=6.5-9.0
E.Coli=126/100ml
	
NH3(ac/ch)=TVS
CL2(ac)=0.019
CL2(ch)=0.011
CN=0.005
S=0.002	
B=0.75
NO2=0.5
NO3=10
Cl=250
SO4=WS	
As(ac)=340
As(ch)=0.02(Trec)
Cd(ac/ch)=TVS
CrIII(ac)=50(Trec)
CrVI(ac/ch)=TVS
Cu(ac/ch)=TVS	
Fe(ch)=WS(dis)
Fe(ch)=1000(Trec)
Pb(ac/ch)=TVS
Mn(ac/ch)=TVS
Mn(ch)=WS(dis)	
Hg(ch)=0.01(tot)
Ni(ac/ch)=TVS
Se(ac/ch)=TVS
Ag(ac)=TVS
Ag(ch)=TVS(tr)
Zn(ac/ch)=TVS	
Temporary modification:
As(ch)=hybrid
Expiration date of 12/31/21.

REGION: 4 & 7

BASIN: FOUNTAIN CREEK 	
Desig	
Classifications	
NUMERIC STANDARDS	
TEMPORARY
MODIFICATIONS
AND
QUALIFIERS	

	PHYSICAL
and
BIOLOGICAL	INORGANIC
mg/l	METALS
ug/l		

Stream Segment Description							

1a.	Mainstem of Fountain Creek, including all tributaries, lakes, wetlands and reservoirs, from the source to a point immediately above the confluence with Monument Creek, except for specific listings in segment 1b.

Aq Life Cold 1
Recreation E
Water Supply
Agriculture	
D.O. = 6.0 mg/l
D.O. (sp)=7.0 mg/l
pH = 6.5-9.0
E.Coli=126/100ml
	
NH3(ac/ch)=TVS
CL2(ac)=0.019
CL2(ch)=0.011
CN=0.005
S=0.002	
B=0.75
NO2=0.05
NO3=10
Cl=250
SO4=WS	
As(ac)=340
As(ch)=0.02(Trec)
Cd(ac)=TVS(tr)
Cd(ch)=TVS
CrIII(ac)=50(Trec)
CrVI(ac/ch)=TVS
Cu(ac/ch)=TVS	
Fe(ch)=WS(dis)
Fe(ch)=1000(Trec)
Pb(ac/ch)=TVS
Mn(ac/ch)=TVS
Mn(ch)=WS(dis)	
Hg(ch)=0.01(tot)
Ni(ac/ch)=TVS
Se(ac/ch)=TVS
Ag(ac)=TVS
Ag(ch)=TVS(tr)
Zn(ac/ch)=TVS	
Temporary modification
type (iii):
Se(ch)=8.7 Expiration date 12/31/2013.
 
Temporary modification:
As(ch)=hybrid
Expiration date of 12/31/21.

3a.	All tributaries to Fountain Creek which are within the boundaries of National Forest or Air Force Academy lands, including all wetlands, lakes and reservoirs, from a point immediately above the confluence with Monument Creek to the confluence with the Arkansas River, except for the mainstem of Monument Creek in the Air Force Academy lands, lands, except for specific listings in segment 3b.

Aq Life Cold 1
Recreation E
Water Supply
Agriculture	
D.O. = 6.0 mg/l
D.O. (sp)=7.0 mg/l
pH = 6.5-9.0
E.Coli=126/100ml
	
NH3(ac/ch)=TVS
CL2(ac)=0.019
CL2(ch)=0.011
CN=0.005
S=0.002	
B=0.75
NO2=0.05
NO3=10
Cl=250
SO4=WS	
As(ac)=340
As(ch)=0.02(Trec)
Cd(ac)=TVS(tr)
Cd(ch)=TVS
CrIII(ac)=50(Trec)
CrVI(ac/ch)=TVS
Cu(ac/ch)=TVS	
Fe(ch)=WS(dis)
Fe(ch)=1000(Trec)
Pb(ac/ch)=TVS
Mn(ac)=TVS
Mn(ac/ch)=TVS Mn(ch)=WS(dis) 	
Hg(ch)=0.01(tot)
Ni(ac/ch)=TVS
Se(ac/ch)=TVS
Ag(ac)=TVS
Ag(ch)=TVS(tr)
Zn(ac/ch)=TVS	
Temporary modification:
As(ch)=hybrid
Expiration date of 12/31/21.	

3b. Bear Creek , and all tributaries, from the source to a point upstream of GPS coordinates N3847682, W 10454917 (this location is at elevation 8,200 feet above sea level at a 250° angle and 3,000 feet from the trailhead of the Mount Buckhorn Trail off High Drive).	
OW	
Aq Life Cold 1
Recreation E
Water Supply
Agriculture	
D.O. = 6.0 mg/l
D.O. (sp)=7.0 mg/l
pH = 6.5-9.0
E.Coli=126/100ml
	
NH3(ac/ch)=TVS
CL2(ac)=0.019
CL2(ch)=0.011
CN=0.005
S=0.002	
B=0.75
NO2=0.05
NO3=10
Cl=250
SO4=WS	
As(ac)=340
As(ch)=0.02(Trec)
Cd(ac)=TVS(tr)
Cd(ch)=TVS
CrIII(ac)=50(Trec)
CrVI(ac/ch)=TVS
Cu(ac/ch)=TVS	
Fe(ch)=WS(dis)
Fe(ch)=1000(Trec)
Pb(ac/ch)=TVS
Mn(ac)=TVS
Mn(ac/ch)=TVS Mn(ch)=WS(dis) 	
Hg(ch)=0.01(tot)
Ni(ac/ch)=TVS
Se(ac/ch)=TVS
Ag(ac)=TVS
Ag(ch)=TVS(tr)
Zn(ac/ch)=TVS	
Temporary modification:
As(ch)=hybrid
Expiration date of 12/31/21.	

REGION: 7

BASIN: LOWER ARKANSAS RIVER	
Desig	
Classifications	
NUMERIC STANDARDS	
TEMPORARY
MODIFICATIONS
AND
QUALIFIERS	

	PHYSICAL
and
BIOLOGICAL	INORGANIC
mg/l	METALS
ug/l		

Stream Segment Description							

1b.	Mainstem of the Arkansas River from the Colorado Canal headgate to the inlet to John Martin Reservoir.	
UP	
Aq Life Warm 2
Recreation E
Water Supply
Agriculture	
D.O. = 5.0 mg/l
pH = 6.5-9.0
E.Coli=126/100ml
	
NH3(ac/ch)=TVS
CL2(ac)=0.019
CL2(ch)=0.011
CN=0.005
S=0.002	
B=0.75
NO2=0.5
NO3=10
Cl=250
SO4=902	
As(ac)=340
As(ch)=0.02(Trec)
Cd(ac/ch)=TVS
CrIII(ac)=50(Trec)
CrVI(ac/ch)=TVS
Cu(ac/ch)=TVS	
Fe(ch)=WS(dis)
Fe(ch)= 1950(Trec)
Pb(ac/ch)=TVS
Mn(ac/ch)=TVS
Mn(ch)=WS(dis)	
Hg(ch)=0.01(tot)
Ni(ac/ch)=TVS
Se(ac/ch)=TVS
Ag(ac/ch)=TVS
Zn(ac/ch)=TVS	
Temporary modification
type (iii):
Se(ch)=“current condition”
Expiration date of 12/31/2013.

Temporary modification:
As(ch)=hybrid
Expiration date of 12/31/21.

Water + Fish Standards Apply.	

1c.	Mainstem of the Arkansas River from the outlet of John Martin Reservoir to the Colorado/Kansas border.	
UP	
Aq Life Warm 2
Recreation E
Water Supply
Agriculture	
D.O. = 5.0 mg/l
pH = 6.5-9.0
E.Coli=126/100ml
	
NH3(ac/ch)=TVS
CL2(ac)=0.019
CL2(ch)=0.011
CN=0.005
S=0.002	
B=0.75
NO2=0.5
NO3=10
Cl=250
SO4=1900	
As(ac)=340
As(ch)=0.02 (Trec)
Cd(ac/ch)=TVS
CrIII(ac)=50(Trec)
CrVI(ac/ch)=TVS
Cu(ac/ch)=TVS	
Fe(ch)=WS(dis)
Fe(ch)=1000(Trec)
Pb(ac/ch)=TVS
Mn(ch)=642(dis)
Mn(ac/ch)=TVS
Hg(ch)=0.01(tot)	
Ni(ac/ch)=TVS
Se(ac/ch)=TVS
Ag(ac/ch)=TVS
Zn(ac/ch)=TVS
	
Temporary modification
type (iii):
Se(ch)=22.5, 
Expiration date of 12/31/2013.
Temporary modification:
As(ch)=hybrid
Expiration date of 12/31/21.

Water + Fish Standards Apply.	

3a.	Mainstem of the Apishapa River, including all wetlands, tributaries, lakes and reservoirs, from the source to I-25, except for specific listings in segments 3b and 3c.	
	
Aq Life Cold 1
Recreation E
Water Supply
Agriculture	
D.O. = 6.0 mg/l
D.O. (sp)=7.0 mg/l
pH = 6.5-9.0
E.Coli=126/100ml
	
NH3(ac/ch)=TVS
CL2(ac)=0.019
CL2(ch)=0.011
CN=0.005
S=0.002	
B=0.75
NO2=0.05
NO3=10
Cl=250
SO4=WS	
As(ac)=340
As(ch)=0.02(Trec)
Cd(ac)=TVS(tr)
Cd(ch)=TVS
CrIII(ac)=50(Trec)
CrVI(ac/ch)=TVS
Cu(ac/ch)=TVS	
Fe(ch)=WS(dis)
Fe(ch)=1000(Trec)
Pb(ac/ch)=TVS
Mn(ac/ch)=TVS
Mn(ch)=WS(dis)	
Hg(ch)=0.01(tot)
Ni(ac/ch)=TVS
Se(ac/ch)=TVS
Ag(ac)=TVS
Ag(ch)=TVS(tr)
Zn(ac/ch)=TVS	
Temporary modification:
As(ch)=hybrid
Expiration date of 12/31/21.	

5a.	Mainstem of the North Fork of the Purgatoire River, including all tributaries, wetlands, lakes and reservoirs, from the source to the confluence with the Purgatoire River; mainstem of the Middle Fork of the Purgatoire River, including all tributaries, wetlands, lakes, and reservoirs, from the source to the USGS gage at Stonewall; the mainstem of the Middle Fork of the Purgatoire River from the USGS gage at Stonewall to the confluence with the North Fork of the Purgatoire River; mainstem of the South Fork of the Purgatoire River, including all tributaries, wetlands, lakes, and reservoirs, from the source to Tercio; the mainstem of the South Fork of the Purgatoire River from Tercio to the confluence with the Purgatoire River; mainstem of the Purgatoire River  to Interstate 25, except for the specific listing in segment 5b; mainstem of Long Creek from the source to the confluence with Trinidad Reservoir; mainstem of Raton Creek from the source to the confluence with the Purgatoire River.	
	
Aq Life Cold 1
Recreation E
Water Supply
Agriculture	
D.O. = 6.0 mg/l
D.O. (sp)=7.0 mg/l
pH = 6.5-9.0
E.Coli=126/100ml
	
NH3(ac/ch)=TVS
CL2(ac)=0.019
CL2(ch)=0.011
CN=0.005
S=0.002	
B=0.75
NO2=0.05
NO3=10
Cl=250
SO4=WS	
As(ac)=340
As(ch)=0.02(Trec)
Cd(ac)=TVS(tr)
Cd(ch)=TVS
CrIII(ac)=50(Trec)
CrVI(ac/ch)=TVS
Cu(ac/ch)=TVS	
Fe(ch)=WS(dis)
Fe(ch)=1000(Trec)
Pb(ac/ch)=TVS
Mn(ac/ch)=TVS
Mn(ch)=WS(dis)	
Hg(ch)=0.01(tot)
Ni(ac/ch)=TVS
Se(ac/ch)=TVS
Ag(ac)=TVS
Ag(ch)=TVS(tr)
Zn(ac/ch)=TVS	
Temporary modification
type (iii):
Se(ch)=11.2. 
  Expiration date of 12/31/2013.

Temporary modification:
As(ch)=hybrid
Expiration date of 2/31/21.	

. . . .
32.51	STATEMENT OF BASIS SPECIFIC STATUTORY AUTHORITY AND PURPOSE APRIL 8, 2013 RULEMAKING; FINAL ACTION MAY 13, 2013 EFFECTIVE DATE SEPTEMBER 30, 2013
The provisions of C.R S. 25-8-202(1)(a), (b) and (2); 25-8-203; 25-8-204; and 25-8-402; provide the specific statutory authority for adoption of these regulatory amendments.  The Commission also adopted in compliance with 24-4-103(4) C.R.S. the following statement of basis and purpose.
BASIS AND PURPOSE
In August of 2005, the Commission adopted revisions to the Basic Standards and Methodologies for Surface Waters (Regulation #31) to add a Water + Fish (W+F) table value standard for chronic arsenic of 0.02 micrograms per liter (μg/L). W+F standards are numeric human health-based water quality standards that are calculated protective values that take into account the combined exposure from the pollutant in drinking water and the pollutant accumulated in fish flesh. This criterion automatically went into effect for Aquatic Life Class 1 waters which also have a Domestic Water Supply use, when the changes to the Basic Standards became effective.  It was also adopted on a segment by segment basis for Aquatic Life class 2 waters with Domestic Water Supply where the Commission determined there are fish of a catchable size of species that are normally consumed.  Because of the complicated nature of the arsenic standards, specific values were added to the basin tables in the basin hearings between 2006 and 2009.
In this hearing, the Commission adopted temporary modifications for W+F chronic arsenic where a permitted discharger with a water quality–based effluent limit compliance problem exists. The adopted temporary modification is listed in the regulation tables as “As(ch)=hybrid”. An explanation of the temporary modification and its expected implementation into control requirements, such as Colorado Discharge Permit System (CDPS) effluent limitations, is described in 32.6(2)(d). The temporary modification was established by the Commission to allow for a temporarily less stringent application of the chronic arsenic standard in control requirements for both existing discharges and new or increased discharges. 
For discharges existing on or before 6/1/2013, the temporary modification adopted for W+F chronic arsenic is “current condition”, expiring on 12/31/2021. The Commission intends that, when implementing the temporary modification of “current condition” in a CDPS permit, the Division will assess the current effluent quality, recognizing that it changes over time due to variability in treatment facility removal efficiency and influent loading from natural or anthropogenic sources, and due to changes in the influent flow and concentration over time. Maintaining the current condition will include maintaining permitted total arsenic loading to a treatment facility from arsenic contributors at the levels existing on the effective date of the temporary modification, while expressly allowing for variability in such loading due to changes in effluent quality as described above and due to changes in the influent flow and concentration over time within the permitted design flow of that facility. The Commission understands that the Division's past practice implementing this requirement in permits has been through reporting regarding the arsenic loading to the facility, and not through numeric effluent limitations. The Commission intends that the Division will continue this practice. For facilities that lack enough representative data to quantify arsenic loading, the permittee may satisfy reporting requirements through narrative descriptions of potential sources of arsenic. No permit action shall be approved that allows an increase in permitted total arsenic loading to a treatment facility. The expiration date of the temporary modification was set at 12/31/21 to allow for CDPS permits that are issued prior to the effective date of anticipated changes to the chronic arsenic standard in the 2016 Basic Standards Rulemaking to not have the temporary modification expire within the term of a permit. The Commission adopted this temporary modification to allow time for the Division, dischargers and stakeholders to continue a workgroup process to resolve the uncertainty regarding the appropriateness of the W+F chronic arsenic standard of 0.02 μg/L with respect to a technologically feasible level of treatment. 
For new or increased discharges that commence on or after 6/1/2013, the temporary modification adopted is As(ch) = 0.02–3.0 μg/L (Trec), expiring on 12/31/2021. The Commission decided that since the technologically achievable arsenic level is less stringent than the calculated W+F criterion, the temporary modification for new or increased discharges will be a range of 0.02-3.0 μg/L. The first number in the range is the health-based value, based on the Commission’s established methodology for human health-based standards that protect against the combined exposure of drinking water and eating fish. The second number in the range is the Commission’s initial determination of a technologically achievable value for arsenic, set at 3.0 μg/L. Control requirements, such as discharge permits effluent limitations, shall be established using the first number in the range as the ambient water quality target, provided that no effluent limitation shall require an “end of pipe” discharge level more restrictive than the second number in the range during the effective period for this temporary modification. The expiration date of the temporary modification was set at 12/31/21 to allow for CDPS permits that are issued prior to the effective date of anticipated changes to the chronic arsenic standard in the 2016 Basic Standards Rulemaking to not have the temporary modification expire within the term of a permit. The Commission adopted this temporary modification to allow time for the Division, dischargers and stakeholders to continue a workgroup process to resolve the uncertainty regarding the appropriateness of the W+F chronic arsenic standard of 0.02 μg/L with respect to a technologically feasible level of treatment. 
The technologically feasible level of 3.0 μg/L for arsenic is based upon testimony heard by the Commission at the December 13, 2011 Emergency Revisions to Regulation #38. At the December 13, 2011 hearing, the Commission determined, as a practical manner, that 3.0 μg/L is the lowest level that is technologically achievable for common types of water treatment facilities. At the April 8, 2013 Rulemaking, the Commission heard testimony that concurred with the finding from December 13, 2011 that an initial reasonable  lower limit of treatment technology for arsenic is 3.0 μg/L, pending further investigation by the Division, dischargers and stakeholders. The Division intends to address the uncertainty of the W+F chronic arsenic standard with respect to a technologically feasible level of treatment through a continued workgroup process, and propose a revised W+F chronic arsenic standards as part of the 2016 Basic Standards Rulemaking Hearing
Temporary modifications were adopted on the following segments. The segments identified have the previously adopted W+F chronic arsenic standard of 0.02 μg/L and an identified CDPS permit or permits that discharge immediately to or directly above the identified segment. 
Upper Arkansas River 1b
Upper Arkansas River 3
Upper Arkansas River 5
Upper Arkansas River 12a
Upper Arkansas River 12b
Upper Arkansas River 13
Upper Arkansas River 15
Upper Arkansas River 16c
Upper Arkansas River 17a
Upper Arkansas River 19
Upper Arkansas River 20
Upper Arkansas River 24
Middle Arkansas River 2
Middle Arkansas River 3
Middle Arkansas River 5
Middle Arkansas River 7
Middle Arkansas River 9
Middle Arkansas River 11
Middle Arkansas River 13
Middle Arkansas River 17
Middle Arkansas River 18b
Fountain Creek 1a
Fountain Creek 3a
Fountain Creek 3b
Lower Arkansas River 1b
Lower Arkansas River 1c
Lower Arkansas River 3a
Lower Arkansas River 5a
PARTIES TO THE RULEMAKING HEARING
1.	Colorado Mining Association
2.	Union Gold, Inc.
3.	Colorado Department of Transportation
4.	City of Colorado Springs and Colorado Springs Utilities
5.	Town of Crested Butte
6.	Mountain Coal Company
7.	Centennial Water and Sanitation District
8.	MillerCoors, LLC
9.	Plum Creek Wastewater Authority
10.	Tri-State Generation & Transmission Association
11.	Climax Molybdenum Company
12.	Littleton/Englewood Wastewater Treatment Plant
13.	Eagle River Water and Sanitation District
14.	City of Boulder
15.	City and County of Denver
16.	Parker Water and Sanitation District
17.	U.S. Energy Corp.
18.	U.S. Environmental Protection Agency
19.	City of Greeley