Virginia Administrative Code › Title 9 - ENVIRONMENT › Agency 25 - STATE WATER CONTROL BOARD › Chapter 260 - WATER QUALITY STANDARDS › Part IX - River Basin Section Tables › Section 9VAC25-260-380 - Special standards column

Current through Register Vol. 40, No. 24, July 15, 2024
A.
				  Bacteria criteria. All surface waters have criteria for fecal coliform
				  bacteria. The bacteria criteria for shellfish waters are set forth in
				  9VAC25-260-160; the criteria
				  applying to recreational waters are found in
				  9VAC25-260-170. The letter "a" in
				  the special standards column next to a river basin section indicates that there
				  are shellfish waters somewhere within that section and the bacteria criteria
				  for shellfish waters applies to those shellfish waters. (It should be noted
				  that even though the column contains the letter "a" the entire section may not
				  be shellfish waters.)
B. Natural
				  variation. In some cases natural water quality does not fall within the
				  criteria set by these standards. (For example streams in some areas of the
				  state may naturally exceed the usual pH range of 6.0 to 9.0.) In these
				  instances the board may have set more appropriate criteria that reflect natural
				  quality, and this special limit is shown in the special standards
				  column.
C. Additional requirements.
				  In other cases the basic water quality parameters of DO, pH, temperature, and
				  bacteria have not been sufficient to protect water quality in certain areas,
				  and effluent limits or treatment requirements have been established for these
				  areas. This fact is also indicated in the special standards column. If the
				  applicable standard was too long to print in its entirety in that column, the
				  column contains only a lower case letter, and the standard itself will be found
				  in the special standards
				  9VAC25-260-310 under that
				  letter.
D. Other special standards
				  or designations.
1. Public water supplies
				  (PWS). Sections that are public water supplies are indicated in the special
				  standards column with a PWS. This designation indicates that additional
				  criteria are applicable in this section. See
				  9VAC25-260-140 B for applicable
				  criteria. Taste and odor criteria to maintain acceptable taste, odor or
				  aesthetic quality of drinking water apply at the drinking water
				  intake.
2. Nutrient enriched waters
				  (NEW). If a section contains a waterbody that has been designated as nutrient
				  enriched in
				  9VAC25-260-350, the special
				  standards column indicates this with the letters "NEW-" followed by a number.
				  The appropriate waterway can be found listed in
				  9VAC25-260-350. The entire section
				  is not necessarily nutrient enriched, only that portion specifically listed in
				  9VAC25-260-350.
3. Exceptional state waters (ESW). If a
				  section contains a waterbody that has been designated as exceptional state
				  waters in 9VAC25-260-30 A 3 the special
				  standard column indicates this with ESW followed by a number. The appropriate
				  waterway can be found listed in
				  9VAC25-260-30 A 3 c. The entire
				  section within the basin table is not necessarily designated as exceptional
				  state waters, only that portion specifically listed in
				  9VAC25-260-30 A 3 c.
4. If a section contains a waterbody that has
				  been assigned a special standard (indicated by lower case letters in the
				  special standards column), the appropriate waterway can be found listed in
				  9VAC25-260-310. The special
				  standard does not necessarily apply to the entire section, only that portion
				  specifically listed in
				  9VAC25-260-310.