John Shomaker & Associates What Is and What Isn’t a Brackish Ground-Water Resource? A major new untapped resource? Or a known resource that has been left untapped? The hard part isn’t about the volume of water, but the costs and side effects of withdrawing it. “Safe Yield” definitions. Try to avoid spreading misconceptions?

John Shomaker & Associates Emphasis of Workshop’s Deliberations? Are we interested in major supplies, or filling in the gaps? How far to market? Concentrate on places that can use brackish water already at hand, rather than long pipelines to larger markets? Does this mean concentration on smaller, outlying demands—small communities, industry? Easier to find where demand is difficult to meet, then look for brackish supply? Or inventory supplies first?

John Shomaker & Associates How meaningful is this kind of information? Estimates of total and recoverable water in storage in water planning region 6 [southern San Juan Basin] Volume, acre-feet, TDS less than 1000 mg/L Volume, acre-feet, TDS more than 1000 mg/L TotalRecoverableTotalRecoverable Menefee Formation12,125,00030,2508,620,00019,590 Point Lookout Sandstone 6,750,00013,5006,345,00012,690 Crevasse Canyon Formation 78,370,000290,66018,400,00036,800 Gallup Sandstone36,420,000182,1006,900,00062,100 Westwater Canyon Mbr. 15,380,000123,04013,600,000108,000 Cow Springs-Zuni- Bluff 156,620,0001,296,440small

John Shomaker & Associates What does “recoverable” mean? What are reasonable assumptions as to T, S, Kv, etc. that will govern production? What pumping rates from individual wells? What costs? How long? (Then what?)

John Shomaker & Associates People will want to know if the resource is sustainable. What does “sustainable” mean? Spectrum— Mining—San Juan Basin aquifers, bedrock under the High Plains, Capitan Reef Salvaged evapotranspiration—Estancia, Tularosa, Playas Intercepted baseflow—lower Canadian, Malaga Bend

John Shomaker & Associates Mining The dependency problem. Subsidence—does it matter? Will mining require drying up the playa—and does that matter? There is an element of uncertainty as to effects!

John Shomaker & Associates

Salvaged Evapotranspiration Still requires significant drawdown, and leads to some ecological change. Drying up the playa? What about the phreatophytes and the habitat they form? Blowing dust?

John Shomaker & Associates Intercepted Baseflow Brackish and saline springs contribute to streamflow, and do their part in meeting Compact obligations.

John Shomaker & Associates Whose water is it, anyway? Even ignoring policy and regulation, it’s still useful to have some idea of who’s implicitly claiming the water now. Control of surface—Tribal or Pueblo ownership? Effects on existing rights? OSE interpretation of § ? Water wells Produced water

John Shomaker & Associates Using brackish water automatically presents an environmental problem. Is there also a suitable reinjection zone? Will evaporation ponds cause trouble? Can well casing be depended on (forever) not to leak?

John Shomaker & Associates Bedrock under the High Plains Aquifer Lea County study Depth rangeYield, gpmTDS range Santa Rosa ,950 Rustler ,000 to brine Capitan R.3,900-5, ,300 7,000 to brine San Andres3,700-7, avg. 9,600 to brine

John Shomaker & Associates Capitan Reef Aquifer Very high, erratic Kh. Q/s ~ 90 gpm/ft. Depth-to-top range 2,000 to 3,500 ft. Pumping affects the Pecos Model: even if beyond West Laguna submarine canyon—29 % of pumping after 40 years for hypothetical project in western Lea County.

John Shomaker & Associates Deep ground water in MRG basin fill Fresh to below 3,000 ft? “Near west mesa,” lower Santa Fe and older Tertiary: 5,000-7,000 ft, yields >1,000 gpm?, TDS brackish? Temperature ºF Streamflow-depletion issue.

John Shomaker & Associates Bedrock units under Santa Fe Group in MRG Under “near west mesa:” Entrada is about 12,000 ft, may yield gpm, 5,000 to 11,000 mg/L TDS. Temperature 250ºF San Andres-Glorieta

John Shomaker & Associates Tularosa Basin Eastern Tularosa Basin Brackish (1,000-3,000 mg/L) may be 13 million ac-ft. Saline (>3,000 mg/L) may be 25 million ac-ft. At least east of Jarilla Fault, pumping may affect heads in potable-water reserve, and other users—and critical blocks in CMA. Alamogordo’s experience Central part of basin Low well-yields? Military lands

John Shomaker & Associates Jornada Basin 100 million ac-ft resource (whole range of TDS) —but drawdowns in southern end of basin may be close to the limit with continued pumping under existing rights.

John Shomaker & Associates

Obscure corners: San Augustin Basin Estimated 8.9 million ac-ft with >1,000 mg/L, in alluvium in western part of basin. Salt Basin 30,000-50,000 ac-ft/yr “sustainable,” with 1,000 to 2,000 mg/L TDS. Southwestern Closed Basins