From: Fasth, Bill
Sent: Fri Jun 05 10:28:09 2015
To: 'Mark Strandberg'
Cc: 'Jennifer Cline'
Subject: RE: Irrigation startup at North Coleman
Importance: Normal
Attachments: image001.gif; Mark, Page 10 of the RWUP includes the following paragraph: The City will revise this procedure if warranted by actual field conditions, in a manner consistent with the goal of protecting surface and groundwater and public health. For example, the calculation for maximum gross irrigation allowed assumes an irrigation efficiency of 85 percent, which is a very conservative value. If the City collects field data demonstrating that use of the table is inaccurate, the City will revise how the maximum gross irrigation is calculated (e.g., decrease the irrigation efficiency from 85 percent to 75 percent). This paragraph was included to provide some latitude for irrigation management, with the primary goal still being protection of surface and groundwater and public health. As far as the City collecting field data to demonstrate that use of the table is inaccurate (or needs to be modified), in my mind, these could include one or all of the following: * the auger boring I described below * yellowing or wilting crops from dry soil conditions * dry soil conditions assessed with a hand squeeze test (no water can be squeezed from the soil sample) I agree that any of these observations should be confirmed with DEQ before startup, and if DEQ wanted to come to N. Coleman to confirm the field observations, they could do that too. With the weather that we have right now, it seems to me that the most dry fields at N. Coleman should be able to take some water very soon. Bill From: Mark Strandberg [mailto:MStrandberg@ringbenderlaw.com] Sent: Friday, June 05, 2015 10:00 AM To: Fasth, Bill; Jason Clifford; jehredt@cityofmolalla.com; J.W. Ring; Phillip Bender Cc: 'Jennifer Cline'; jon patrick; Jonathan Patrick Subject: RE: Irrigation startup at North Coleman We will need to stick with what is currently in the RWUP until DEQ approves any change, but this will be helpful in the event we seek a revision. -Mark From: Fasth, Bill [mailto:bfasth@BrwnCald.com] Sent: Friday, June 05, 2015 9:58 AM To: Jason Clifford; jehredt@cityofmolalla.com Cc: Mark Strandberg; 'Jennifer Cline'; jon patrick; Jonathan Patrick Subject: Irrigation startup at North Coleman Jason and Jake, Mark Strandberg called me yesterday and mentioned that the lagoons are getting full. This prompted me to look at the tables in Appendix N of the RWUP that can be used to calculate maximum allowable gross irrigation. An updated table for N. Coleman is attached. In the updated table, I decreased the irrigation efficiency from 85% down to 75%. I can justify this revision because the value of 85% used in the RWUP was very conservative. Given this update, reaching a moisture block reading of 80% will allow you to irrigate 1 inch of water at N. Coleman. As we discussed at the meeting at Coleman Ranch on 5/1, this rate translates to 4 hr sets with the hand lines and 12 hr sets with the big gun. At that meeting, we also talked about irrigation sections 3 and 4 being the first ones to likely dry out. I don't know if moisture blocks or piezometers are located in those sections but if not, we can probably talk about some other alternatives. For example, an auger boring can be dug down to three feet in either of those sections and allowed to fill with water overnight. If there is no groundwater in the hole the next morning, you should be good to go. After start-up, the fields must be monitored closely to assure no runoff. Also, regarding irrigating in Section 3 just north of Feyrer Park Rd, you will need a 50 foot setback from the roadside ditch. Let me know if you have any questions. I will be available over the weekend too. Bill Bill Fasth 6500 SW Macadam Avenue, Suite 200 Portland, Oregon 97239 bfasth@brwncald.com<mailto:bfasth@brwncald.com> Cell 541.602.9110 [Description: http://help.bc.com/BC_logo_2line_prple.gif]<http://www.brownandcaldwell.com/>
