2017-03-28_REPORT - C1994082

• Permit No: C1994082
• IBM Index Class Name: Report
• Doc Date: 3/28/2017
• Doc Name: Annual Reclamation Report
• From: Seneca Property, LLC
• To: DRMS
• Annual Report Year: 2016
• Permit Index Doc Type: Annual Reclamation Report
• Email Name: JDM
• Email Name: DIH
• Media Type: D
• Archive: No

SEDIMENTATION POND SURVEYS
SP is required to monitor sedimentation ponds for sediment storage capacities. Up through 2015, this
monitoring was conducted by physically surveying each pond each year. This schedule provided a
sediment yield history and gave advanced warning to operations personnel when sediment clean-out work
was needed. Also, SP visually inspects each pond, at a minimum, quarterly each year. During these
inspections, any significant observed change in sediment storage, or noticeable expansion of the sediment
delta at the inlet to the pond, are noted as conditions requiring pond maintenance.
Yearly sediment delivery to the ponds is considerably less than originally calculated, since significant
portions of these watersheds have now been revegetated. Given this consideration, a request was
submitted and approved to monitor sediment accumulations on a five-year schedule for ponds that flow
year-round and to visually inspect any other ponds. The results of the 2015 survey indicate that all ponds
have sufficient sediment storage as shown by Table 3, Sediment Pond Capacities. Additionally, all ponds
have been discharging in compliance with the approved NPDES/CPDS permit effluent limitations. It
should be noted that the measuring flume for NPDES-010 was replaced in August 2015 and the flume for
NPDES-012 was leveled and reset.
TABLE 13.3 SENECA SEDIMENT PONDS - WATER CAPACITY TRENDS
,qi, a,.4R`' .fii.,
ay •F.^•; .. .. p •ti^-,a�,.^� 4 � 1z
Y a M S '.
YEAR
2008
2009
2010
1 2011
2012
2013
1 2014
2015
Y - 010
3.08
7.6
7.6
7.8
8
8
7.7
9.2
9.2
TR -37
Y - 011
0.99
3.6
3.6
3.6
3.6
3.6
3.7
3.6
3.6
TR -37
Y - 011A
0.631
NA
NA
NA
NA
NA
NA
NA
NA
TR -37
Y - 012
0.767
0.7
0.7
1.1
0.83
1.2
1.3
1.3
1.3
TR -37
Y -012A
6.3
6.3
6.1
5.6
5
4.6
4.4
4.4
Y - 013
1.325
4.5
4.4
4.5
4.4
4.3
4.5
4.5
4.5
TR -37
Y - 014
1.6
10.5
7.5
7.6
7.5
7.5
7.5
7
7
TR -37
(*) Required every 2yrs - next surz y 2016
(1) Based on SEDCAD results. fora 10yr124br stonn event.
(2) Remaining capaci�, belon; principal spillway or orifice.
(3) TR 37, page 134A.1-/1.9 (stock pond)
STOCK TANKS & SURGE CONTROL STRUCTURES
There is currently one stock tank in the Yoast area, which is a permanent feature. No new stock tanks or
surge control structures were constructed in 2016.
WILDLIFE MONITORING
Wildlife monitoring was conducted in cooperation with Colorado Parks and Wildlife (CPW) during 2016.
The work included:
3