From: 

To: 

Date: 

Subject: 

"Mower, Barry F" <Barry.F.Mower®state .me . us> 

Beckwith William <beckwith.william@epamail.epa.gov ... 

10/29/98 10:56am 

mixing zone policy 

We have been asked by you guys quite a while ago to write a mixing zone 

rule. We have begun but are not close to finishing. In the meantime we 

have had the following language for a long time . There is debate here 

whether or not it applies only to heat or not because of the way it is 

written. The only formal mixing zones we ever established were for heat, 

but some facilities are thinking about requesting MZs for toxics. Any 

thought about this? 

38 § 451. Enforcement generallyChapter text (MS Word) 

<Picture>After adoption of any classification by the Legislature for 

surface waters or tidal flats or sections thereof, it is unlawful for any 

person, firm, corporation, municipality, association, partnership, 

quasi-municipal body, state agency or other legal entity to dispose of 

any pollutants, either alone or in conjunction with another or others, in 

such manner as will, after reasonable opportunity for dilution, diffusion 

or mixture with the receiving waters or heat transfer to the atmosphere, 

lower the quality of those waters below the minimum requirements of such 

classifications, or where mixing zones have been established by the 

department, so lower the quality of those waters outside such zones, 

notwithstanding any exemptions or licenses which may have been granted or 

issued under sections 413 to 414-B . [1989, c . 890, Pt . A, §40 (aff ) ; Pt. 

B , §50 ( amd) . ) 

<Picture>The department may establish a mixing zone for any discharge at 

the time of application for a waste discharge license. The department 

shall attach a description of the mixing zone as a condition of a license 

issued for that discharge. After opportunity for a hearing in accordance 

with section 345-A, the department may establish by order a mixing zone 

with respect to any discharge for which a license has been issued 

pursuant to section 414 or for which an exemption has been granted by 

virtue of section 413, subsection 2. Prior to the commencement of any 

enforcement action to abate a classification violation, the department 

shall establish in the manner provided in this paragraph a mixing zone 

with respect to the discharge sought to be affected. [1991, c . 66, Pt. A, 

§11 (amd).) 

<Picture>The purpose of a mixing zone is to a l low a reasonable 

opportunity for dilution, diffusion or mixture of poll utants with the 

receiving wa ters before the receiving waters below or surrounding a 

discharge will be tested for classification violations. In determining 

the extent of any mixing zone to be established under this section, the 

department may require from the applicant testimony concerning the nature 

and rate of the discharge; the nature and rate of existing discharges to 

the waterway; the size of the waterway and the rate of flow therein; any 

relevant seasonal, climatic, tidal and natural variations in such size, 

flow, nature and rate; the uses of the waterways in the vicinity of the 

discharge, and such other and further evidence as in the department's 

judgment will enable it to establish a reasonable mixing zone for such 
discharge . An order establishing a mixing zone may provide that the 

extent thereof varies in order to take into account seasonal, c l imatic, 

tidal and natural variations in the size and flow of, and the nature and 

rate of, discharges to the waterway . [1991, c. 824, Pt. A, §85 (amd) . ) 

<Picture.>Where no mixing zones have been establ ished by the department, 

it is unlawful for any person, corporation, municipality or other legal 

entity to dispose of any poll utants, either alone or in conjunction with 

another or others, into any classified surface waters, tidal flats or 

sections thereof, in such manner as will, after reasonable opportunity 

for dilution, diffusion, mixture or heat transfer to the atmosphere, 

lower the quality of any significant segment of those waters, tidal flats 

or sections thereof, affected by such discharge, below the minimum 

requirements of such classification, and notwi t hstanding any licenses 

which may have been granted or issued under secti ons 413 to 414-B. [1989, 

c. 890, Pt. A, §40 (aff); Pt . B, §50 (amd). )