HYDRO30633

• Permit No: M1977410
• IBM Index Class Name: Hydrology
• Doc Date: 7/9/1991
• Doc Name: RATIONALE FOR PUBLIC NOTICE
• Media Type: D
• Archive: No

COLORADO DEPARTMENT O~EALTH, Water Quality Control ~ision
Permit Number CO-0032751 Page 11.
CHANGES TO PERMIT AND RATIONALE FOLLOWING PUBLIC NOTICE PERIOD:
This permit originally went to public notice at the end of 1988. A comment
letter from the permittee dated January 9, 1989 was received by the Division
during the public notice period. Based upon this comment letter, as well as
upon later comments with the permittee (including a later comment letter dated
March 22, 1991) and the changes in the water quality standards for the South
Platte River Basin, certain changes were made to the permit and the rationale.
The following changes were made in the permit:
page 1 -The name of the permittee, the expiration date, and the name of the
Division director were changed. Also, minor revisions were made to the last
full paragraph of page 1 to be consistent with ail current permits being
issued at this time. In general, current permit page revisions have been
included in this permit for consistency with other permits.
page la - The effective dates for the permit were revised. Three seasonal
30-day average limitations were added for the facility discharge flow.
Limitations were changed for potentially dissolved cadmium; monthly
limitations for potentially dissolved cadmium were included.
page lb - Monthly limitations were added for potentially dissolved copper and
potentially dissolved lead. The previous page lb in the draft public notice
permit, which contained acute biomonitoring toxicity limitations, aas deleted,
ince this language is no longer applicable and not relevant to the present
regulations for WET testing.
page lc - Monthly limitations were added for potentially dissolved mercury and
potentially dissolved zinc.
page ld - Monitoring parameters were changed for potentially dissolved
cadmium, potentially dissolved copper, potentially dissolved lead, potentially
dissolved mercury, and potentially dissolved zinc. Monitoring for the metal
parameters was increased to a weekly frequency.
pages le, lf, lg, lh, li - Whole Effluent Toxicity (WET) testing language was
revised to be in accordance with the present permit regulations for WET
testing.
page lk - Additional monitoring requirements were added for instre.am
measurements of flow and total hardness for Coon Track Creek to verify the
assumptions made for redetermining the limitations of this permit.
page 4 - Footnote ~/ was revised and footnote ~ was added for a dLscussion of
the potentially dissolved metal analysis.
The following changes were made in the rationale:
page 1 - The permittee name was changed. The fee category cost wa.a revised to
be in accordance with the current permit administrative fees.
page 2 - The stream low flow discussion and values were revised