m
m
Line 50: Line 50:
 
*If yes, 40 %
 
*If yes, 40 %
 
*If no, 0%
 
*If no, 0%
 
*Additional credit for approved P-sorbing soil amendments = 40 percent if one of the following conditions applies.
 
**5% by volume elemental iron filings above IWS or elevated underdrain
 
**Minimum 5% by volume sorptive media above IWS or elevated underdrain
 
**Minimum 5% by weight water treatment residuals (WTR) to a depth of at least 10 cm (1/3 foot)
 
**Other P sorptive amendments with supporting third party research results showing P reduction for at least 20 year lifespan, P credit commensurate with research results
 
 
</td>
 
</td>
 
<td>0%</td>
 
<td>0%</td>
 
<td>Is soil P content tested to be < 36 mg/kg per Mehlich III test?  
 
<td>Is soil P content tested to be < 36 mg/kg per Mehlich III test?  
If yes, 20 %
+
*If yes, 20 %
If no, 0%
+
*If no, 0%
Does the system include approved P-sorbing soil amendments*?
+
 
For iron enhanced soils, Imbrium or WTRs, additional 40% credit
+
Additional credit for approved P-sorbing soil amendments = 40 percent if one of the following conditions applies.
 +
*5% by volume elemental iron filings above IWS or elevated underdrain
 +
*Minimum 5% by volume sorptive media above IWS or elevated underdrain
 +
*Minimum 5% by weight water treatment residuals (WTR) to a depth of at least 10 cm (1/3 foot)
 +
*Other P sorptive amendments with supporting third party research results showing P reduction for at least 20 year lifespan, P credit commensurate with research results
 
</td>
 
</td>
 
</tr>
 
</tr>
Line 69: Line 67:
 
<td>Internal Water Storage (IWS)</td>
 
<td>Internal Water Storage (IWS)</td>
 
<td>Is soil P content tested to be < 36 mg/kg per Mehlich III test?  
 
<td>Is soil P content tested to be < 36 mg/kg per Mehlich III test?  
If yes, 40 %
+
*If yes, 40 %
If no, 0%
+
*If no, 0%
 
</td>
 
</td>
 
<td> </td>
 
<td> </td>
 
<td>Is soil P content tested to be < 36 mg/kg per Mehlich III test?  
 
<td>Is soil P content tested to be < 36 mg/kg per Mehlich III test?  
If yes, 20 %
+
*If yes, 20 %
If no, 0%
+
*If no, 0%
Does the system include approved P-sorbing soil amendments*?
+
 
For iron enhanced soils, Imbrium or WTRs, additional 40% credit
+
Additional credit for approved P-sorbing soil amendments = 40 percent if one of the following conditions applies.
 +
*5% by volume elemental iron filings above IWS or elevated underdrain
 +
*Minimum 5% by volume sorptive media above IWS or elevated underdrain
 +
*Minimum 5% by weight water treatment residuals (WTR) to a depth of at least 10 cm (1/3 foot)
 +
*Other P sorptive amendments with supporting third party research results showing P reduction for at least 20 year lifespan, P credit commensurate with research results
 
</td>
 
</td>
 
</tr>
 
</tr>

Revision as of 20:17, 11 December 2013

Percent P Removed Via Non-Volume Reduction Treatment.

Caution: NOTE: These percentages apply to the non-volume reduction portion of stormwater runoff. The volume reduction portion of stormwater runoff receives 100 percent credit for particulate and dissolved phosphorus.

Link to this table

Particulate P Dissolved P
Current Proposed Current Proposed
No underdrain 0% 0% 0% 0%
Elevated underdrain 45% Is soil P content tested to be < 36 mg/kg per Mehlich III test?

If yes, 40 % If no, 0%

0% Is soil P content tested to be < 36 mg/kg per Mehlich III test?
  • If no, 0%
  • If yes, is there at least 2 feet of soil above the elevated underdrain? If yes, 20% credit,
  • If no, credit = 0.2*x
Where x = (soil depth above elevated underdrain) /2 feet
  • Additional credit for approved P-sorbing soil amendments = 40 percent if one of the following conditions aapplies.
    • 5% by volume elemental iron filings above IWS or elevated underdrain
    • Minimum 5% by volume sorptive media above IWS or elevated underdrain
    • Minimum 5% by weight water treatment residuals (WTR) to a depth of at least 10 cm (1/3 foot)
    • Other P sorptive amendments with supporting third party research results showing P reduction for at least 20 year lifespan, P credit commensurate with research results
Underdrain at the bottom 91% Is soil P content tested to be < 36 mg/kg per Mehlich III test?
  • If yes, 40 %
  • If no, 0%
0% Is soil P content tested to be < 36 mg/kg per Mehlich III test?
  • If yes, 20 %
  • If no, 0%

Additional credit for approved P-sorbing soil amendments = 40 percent if one of the following conditions applies.

  • 5% by volume elemental iron filings above IWS or elevated underdrain
  • Minimum 5% by volume sorptive media above IWS or elevated underdrain
  • Minimum 5% by weight water treatment residuals (WTR) to a depth of at least 10 cm (1/3 foot)
  • Other P sorptive amendments with supporting third party research results showing P reduction for at least 20 year lifespan, P credit commensurate with research results
Internal Water Storage (IWS) Is soil P content tested to be < 36 mg/kg per Mehlich III test?
  • If yes, 40 %
  • If no, 0%
Is soil P content tested to be < 36 mg/kg per Mehlich III test?
  • If yes, 20 %
  • If no, 0%

Additional credit for approved P-sorbing soil amendments = 40 percent if one of the following conditions applies.

  • 5% by volume elemental iron filings above IWS or elevated underdrain
  • Minimum 5% by volume sorptive media above IWS or elevated underdrain
  • Minimum 5% by weight water treatment residuals (WTR) to a depth of at least 10 cm (1/3 foot)
  • Other P sorptive amendments with supporting third party research results showing P reduction for at least 20 year lifespan, P credit commensurate with research results