MIXING ZONES DO C KET 5 8 -0 1 0 2 -1 4 0 1 Oil je ts pre - mixe d - - PowerPoint PPT Presentation

DO C KET 5 8 -0 1 0 2 -1 4 0 1

MIXING ZONES

Oil je ts pre - mixe d with so a p a re fire d into la ye re d fluid. Pho to g ra ph b y Ste ve Ha re nb e rg , e t a l. UNC Jo int F luids L a b o ra to ry

OUTLINE

• Re vie w c o mme nts re c e ive d
• Disc uss dra ft rule ve rsio n 3
• Disc uss re ma ining se c tio ns (a , c , g a nd

02)

• Sto rmwa te r
• Pre se nta tio n o n no nflo wing wa te rs
• Disc ussio n

COMMENTS RECEIVED

COMMENTERS

• Cle a rwa te r Pa pe r
• E

PA

• I

ACI

• I

MA

• NOAA
• Simplo t

SUMMARY OF COMMENTS

• Se e do c ume nt Summa ry o f Co mme nts

Re c e ive d: Ne g o tia te d Rule Dra ft No . 2, June 27, 2014 c o mme nt de a dline

• Cha ng e s ma de to the dra ft rule we re

in re spo nse to c o mme nts re c e ive d during la st me e ting a s we ll a s writte n c o mme nts

DRAFT RULE VERSION 3

C HA NG ES A ND A DDITIO NS

060.01.d

Dra ft Ve rsion 2 Mixing zo ne s sha ll no t c a use unre a so na b le inte rfe re nc e with, o r da ng e r to , e xisting b e ne fic ia l use s. Unre a so na b le inte rfe re nc e with, o r da ng e r to , e xisting b e ne fic ia l use s inc lude s, b ut is no t limite d to , the fo llo wing : Dra ft Ve rsion 3 Mixing zo ne s sha ll no t c a use unre a so na b le inte rfe re nc e with, o r da ng e r to , e xisting b e ne fic ia l use s, inc luding spe c ie s liste d unde r the E nda ng e re d Spe c ie s Ac t. Unre a so na b le inte rfe re nc e with, o r da ng e r to , e xisting b e ne fic ia l use s inc lude s, b ut is no t limite d to , the fo llo wing :

060.01.d.i

Dra ft Ve rsion 2

I nte rfe re nc e with fish pa ssa g e , spa wning , e g g inc ub a tio n o r re a ring .

Dra ft Ve rsion 3

Blo c king fish pa ssa g e , o r pre ve nting suc c e ssful spa wning , e g g inc ub a tio n o r re a ring .

060.01.d.ii

Dra ft Ve rsion 2

Je o pa rdy to E nda ng e re d Spe c ie s Ac t liste d spe c ie s, o r de struc tio n o r a dve rse mo dific a tio n to c ritic a l ha b ita t.

Dra ft Ve rsion 3

Re mo ve d this ite m a nd inc lude d te xt in 060.01.d to c a ll o ut e nda ng e re d spe c ie s.

060.01.d.iii

Dra ft Ve rsion 2

He a t in the disc ha rg e tha t c a use s the rma l sho c k, insta nt le tha lity o r lo ss o f c o ld wa te r re fug ia .

Dra ft Ve rsion 3

No w 060.01.d.ii – He a t in the disc ha rg e tha t c a use s the rma l sho c k, le tha lity o r lo ss

• f c o ld wa te r re fug ia .

Adde d de finitio n o f the rmal sho c k.

T he r mal Shoc k. A ra pid te mpe ra ture c ha ng e tha t c a use s

a q ua tic life to b e c o me diso rie nte d o r mo re susc e ptib le to pre da tio n o r dise a se .

060.01.d.iv

Dra ft Ve rsion 2 I n de te rmining whe the r a mixing zo ne will c a use unre a so na b le inte rfe re nc e with o r da ng e r to , e xisting a q ua tic life b e ne fic ia l use s, the De pa rtme nt sha ll c o nside r the b io a c c umula tive na ture

• f the po lluta nts invo lve d.

Dra ft Ve rsion 3

No w 01.d.iii – Bio a c c umula tio n o f po lluta nts (a s de fine d in Se c tio n 010) g re a te r tha n the b io a c c umula tio n fa c to r use d in c a lc ula tio n o f wa te r c o lumn c rite ria .

060.01.d.v

Dra ft Ve rsion 2

Ac ute to xic ity to a q ua tic life o utside the zo ne o f initia l dilutio n.

Dra ft Ve rsion 3

No w 01.d.iv – L e tha lity to a q ua tic life pa ssing thro ug h the mixing zo ne .

060.01.d.vi

Dra ft Ve rsion 2

Co nc e ntra tio ns o f po lluta nts tha t e xc e e d Ma ximum Co nta mina nt L e ve ls a t drinking wa te r inta ke struc ture s.

Dra ft Ve rsion 3

No w 01.d.v – Co nc e ntra tio ns o f po lluta nts tha t e xc e e d Ma ximum Co nta mina nt L e ve ls a t drinking wa te r inta ke struc ture s.

060.01.d.vii

Dra ft Ve rsion 2

I nte rfe re nc e with pub lic swimming a re a s.

Dra ft Ve rsion 3

No w 01.d.vi – Unre a so na b le inte rfe re nc e with re c re a tio na l use s.

060.01.i.ii

Dra ft Ve rsion 2

A la rg e r mixing zo ne tha t e xc e e ds the limits is ne e de d b y the disc ha rg e r a nd do e s no t c a use a n unre a so na b le inte rfe re nc e with, o r da ng e r to , e xisting b e ne fic ia l use s a s de sc rib e d in Sub se c tio n 060.01.d, a nd the mixing zo ne me e ts the o the r re q uire me nts se t fo rth in Se c tio n 060.

Dra ft Ve rsion 3

Adde d –

T he disc ha rg e r sha ll pro vide to the De pa rtme nt a n a na lysis tha t de mo nstra te s a la rg e r mixing zo ne is ne e de d g ive n siting , te c hno lo g ic a l a nd ma na g e ria l o ptio ns.

060.01.j

Dra ft Ve rsion 2

T he De pa rtme nt re c o mme nds the fo llo wing e le me nts whe n de sig ning a n

• utfa ll:

Dra ft Ve rsion 3

T he fo llo wing e le me nts sha ll b e c o nside re d whe n de sig ning a n o utfa ll:

060.01.a

M IXING ZO NES IN IM PA IRED WA TERS

060.01.a

Dra ft Ve rsion 2

Mixing zo ne s sha ll no t b e a utho rize d fo r a g ive n po lluta nt whe n the re c e iving wa te r do e s no t me e t wa te r q ua lity c rite ria fo r tha t po lluta nt.

Dra ft Ve rsion 3

Adde d – Mixing zo ne s sha ll no t b e a utho rize d fo r E . c o li.

Suggested changes to 060.01.a

Mixing zo ne s sha ll no t b e a utho rize d fo r a g ive n po lluta nt whe n the re c e iving wa te r do e s no t me e t wa te r q ua lity c rite ria fo r tha t po lluta nt unle ss the a utho rize d disc ha rg e me e ts a n a ppro ve d T MDL a llo c a tio n o r o the r a pplic a b le re q uire me nts. Mixing zo ne s sha ll no t b e a utho rize d fo r E . c o li.

STORMWATER

060.01

Mixing Zo ne s fo r Po int So urc e Wa ste wa te r Disc ha rg e s

060.01.c

SIZE A ND C O NC ENTRA TIO N BA SED O N DESIG N FLO W

060.01.c

T he size o f the mixing zo ne (s) a nd the c o nc e ntra tio n o f po lluta nt(s) pre se nt sha ll b e b a se d o n the po int so urc e wa ste wa te r pe rmitte d de sig n flo w. T he De pa rtme nt sha ll no t a utho rize a mixing zo ne tha t is de te rmine d to b e la rg e r tha n is ne c e ssa ry.

060.01.g

A DJA C ENT M IXING ZO NES

060.01.g

Adja c e nt mixing zo ne s o f inde pe nde nt a c tivitie s sha ll no t o ve rla p.

060.02

PO INTS O F C O M PLIA NC E

060.02

Points of Complianc e for Nonpoint Sour c e Disc har ge s. While it is re c o g nize d tha t

mixing do e s o c c ur fo r no npo int so urc e s, due to the ir g e ne ra lly inte rmitte nt a nd diffuse na ture , the spe c ific a tio n o f mixing zo ne s fo r no npo int so urc e s is no t pra c tic a b le . I nste a d, the De pa rtme nt ma y e sta b lish po ints fo r mo nito ring c o mplia nc e with a mb ie nt wa te r q ua lity c rite ria in a sso c ia tio n with a utho rize d no npo int disc ha rg e s.

060.02 Draft Version 3

Points of Complianc e for Nonpoint Sour c e Disc har ge s. While it is re c o g nize d tha t

mixing do e s o c c ur fo r no npo int so urc e s, due to the ir g e ne ra lly inte rmitte nt a nd diffuse na ture , the spe c ific a tio n o f mixing zo ne s fo r no npo int so urc e s ma y no t b e pra c tic a b le . I nste a d T hus, the De pa rtme nt ma y e sta b lish po ints fo r mo nito ring c o mplia nc e with a mb ie nt wa te r q ua lity c rite ria in a sso c ia tio n with a utho rize d no npo int disc ha rg e s.

Suggested 060.02

Points of Complianc e for 404 Dr e dge and F ill Ac tivitie s and Nonpoint Sour c e Disc har ge s.

While it is re c o g nize d tha t mixing ma y o c c ur fo r no npo int so urc e disc ha rg e s a nd fro m 404 dre dg e a nd fill a c tivitie s, due to the ir g e ne ra lly inte rmitte nt a nd diffuse na ture , the spe c ific a tio n o f mixing zo ne s fo r no npo int the se so urc e s ma y no t b e pra c tic a b le . I nste a d T hus, the De pa rtme nt ma y e sta b lish po ints fo r mo nito ring c o mplia nc e with a mb ie nt wa te r q ua lity c rite ria in a sso c ia tio n with the se a utho rize d no npo int disc ha rg e s.

M IXING IN LA KES A ND RESERVO IRS

NONFLOWING WATERS

DO N A . ESSIG , IDEQ JULY 1 0 , 2 0 1 4

OUTLINE

• Wha t is me a nt b y no nflo wing
• Wha t’ s the pro b le m
• Unde rsta nding ne a r-fie ld ve rsus fa r-fie ld

mixing

• Wha t ha ve so me o the r sta te s do ne
• So me o ptio ns
• Our pro po sa l

WHAT IS MEANT BY NONFLOWING?

• L

a ke s, re se rvo irs, we tla nds …

• Wha t wo uld b e c la ssifie d a s le ntic wa te rs fro m

a n e c o lo g ic a l pe rspe c tive

• F

a irly o b vio us, b ut we la c k a c le a r de finitio n in rule

• F

lo w ‘ dire c tio n’ ha rd to disc e rn, ma y va ry

• L

ittle to no ve lo c ity

• Wa te r b o die s tha t typic a lly the rma lly stra tify in

te mpe ra te c lima te s

WHAT’S THE PROBLEM

• Sta g na nt o r no nflo wing wa te rs do n’ t mix

ve ry we ll

• Mo st o f the c o nc e pts a nd la ng ua g e in

E PA g uida nc e a nd o ur rule s a ddre ss mixing a s if the re we re a sing le dire c tio n

• f flo w:
• “L
• w flo w de sig n disc ha rg e c o nditio ns”
• Zo ne o f pa ssa g e
• Org a nism drift time

NEAR-FIELD VERSUS FAR-FIELD

• Mixing pro c e sse s c a n b e divide d into

ne a r-fie ld a nd fa r-fie ld

• Ba se d o n mo me ntum o r e ne rg y o f flo w
• Ne a r fie ld mixing is do mina te d b y disc ha rg e

flo w

• I

n stre a ms fa r fie ld mixing is do mina te d re c e iving wa te r flo w

• I

n la ke s fa r fie ld mixing de pe nds o n diffusio n, de nsity c urre nts, wind – in g e ne ra l is ve ry slo w

• We c a n c o ntro l ne a r-fie ld mixing

A LOOK AT SOME OTHER STATES

• Se nt o ut se t o f six q ue stio ns to sta te s,

re c e ive d 12 re plie s

• Mo st sta te s do a llo w mixing in la ke s (8) o r

re se rvo irs (9), 2 with so me e xc e ptio ns

• Mo st sta te s do no t a llo w mixing in

we tla nds (7), 2 unc le a r

• Ho we ve r, like I

da ho , mo st sta te s do no t ha ve de finitio ns fo r va rio us wa te r b o dy type s

OPTIONS FOR MIXING IN LENTIC WATERS

1) Do no t a llo w it g o ing fo rwa rd 2) Allo w limite d mixing zo ne s. Optio ns inc lude :

a ) L imit fra c tio n o f surfa c e a re a a s I da ho do e s c urre ntly b ) L imit a b so lute size , in me te rs o r fe e t c ) Co mb ine the pre vio us 2, with a “whic he ve r is sma lle r” c o nstruc t d ) Re q uire a diffuse r to ma ximize ne a r-fie ld mixing e ) L imit b a se d o n e xte nt o f dilutio n ne a r-fie ld mixing a c hie ve s

OUR PROPOSAL

Our pre limina ry dra ft rule is sile nt o n mixing limita tio ns in la ke s a nd re se rvo irs Our sug g e stio n is thre e -fo ld: L imit size b a se d o n c o mb ina tio ns o f a re a a nd a b so lute dime nsio n, e .g . no mo re tha n 5% o f the a re a o r 100 me te rs fro m the po int o f disc ha rg e , whic he ve r is sma lle r. Re q uire a diffuse r. Pro hib it sho re -hug g ing plume s.

SUGGESTED LANGUAGE FOR 060.01.h

• h. Mixing zo ne s sha ll me e t the fo llo wing re stric tio ns;

pro vide d, ho we ve r, tha t the De pa rtme nt ma y a utho rize mixing zo ne s tha t va ry fro m the re stric tio ns unde r the c irc umsta nc e s se t fo rth in Sub se c tio n 060.01.i. b e lo w:

• i. F
• r flo wing wa te rs:

(1) T he width o f a mixing zo ne is no t to e xc e e d twe nty-five pe rc e nt (25%) o f the stre a m width; a nd (2) T he mixing zo ne sha ll no t inc lude mo re tha n twe nty-five pe rc e nt (25%) o f the lo w flo w de sig n disc ha rg e c o nditio ns a s se t fo rth in Sub se c tio n 210.03.b o f the se rule s; o r le a ning to wa rds using rive rs/ stre a ms ra the r tha n flo wing .

SUGGESTED LANGUAGE FOR 060.01.h

• ii. F
• r a ll ne w disc ha rg e s to no nflo wing wa te rs a utho rize d

a fte r July 1, 2015: (1) T he size o f the mixing zo ne is no t to e xc e e d 5%

• f the to ta l o pe n surfa c e a re a o f the wa te r b o dy o r

100 me te rs fro m the po int o f disc ha rg e , whic he ve r is sma lle r; (2) Sho re -hug g ing plume s a re no t a llo we d; a nd (3) Diffuse rs sha ll b e use d.

DEFINE LAKES AND RESERVOIRS

• L

a ke o r re se rvo ir: A wa te r b o dy with a de te ntio n time a ro und the time o f a nnua l lo w o utflo w g re a te r tha n 15 da ys.

• De te ntio n time : Vo lume o f a wa te r

b o dy divide d b y o utflo w. T his c a n b e c a lc ula te d fo r a ny time pe rio d.

SUGGESTED LANGUAGE FOR 060.01.h

• iii. Re se rvo irs with a me a n de te ntio n time
• f fifte e n (15) da ys o r g re a te r sha ll b e

c o nside re d la ke s fo r this purpo se .

COMMENT DEADLINE JULY 24, 2014

THA NK YO U