Here is a lot of information some of which I had in archives. Check on all of it before using.
Hope this helps
Walter Eason Claims Administrator, GPAA
Information a few years old now but Green Mountain National Forest in VT allowed Gold Panning. The same was true of Smugglers Notch and Camp Plymouth State Parks. White Mountain National Forest, NH also allowed gold panning and sluicing less than 3 foot long. no power or mechanized equipment allowed. New Hampshire also has a dredge permit on file at http://www2.des.state.nh....its_Query.aspx and it was last updated on 11/9/2016, not sure where it would be used maybe on private or National Forest land.
Main: 38 M.R.S. §§ 480-Q(5)
5-A. Motorized recreational gold prospecting. Notwithstanding section 480-C, a permit is not required for motorized recreational gold prospecting as long as the provisions of this subsection are met.
A. A person may perform motorized recreational gold prospecting only from June 15th to September 15th and only with written permission of the relevant landowner. [2013, c. 260, §1 (NEW).]
B. A person may not perform motorized recreational gold prospecting that causes an undue adverse effect on natural resources. The area in which the motorized recreational gold prospecting is performed must be kept free of litter, trash and any other materials that may constitute a hazardous or nuisance condition. [2013, c. 260, §1 (NEW).]
C. The following provisions limit the use of equipment in motorized recreational gold prospecting.
D. A person may not use mercury, nitric acid or other chemicals for extraction in motorized recreational gold prospecting. [2013, c. 260, §1 (NEW).]
E. A person may not perform motorized recreational gold prospecting in a manner that:
F. Upon completion of one or more consecutive days of motorized recreational gold prospecting, a person who performed the motorized recreational gold prospecting shall smooth out dredge spoils and refill dredge holes below the normal high-water mark of the stream in order to restore the approximate original contours of the stream bottom and not deflect the current. [2013, c. 260, §1 (NEW).]
G. Motorized recreational gold prospecting is prohibited within the following areas:
(4) The following areas of critical or high-value brook trout or Atlantic salmon habitat:
(a) Bemis Stream and tributaries in Township D and Rangeley Plantation;
(b) Bond Brook in the City of Augusta and the Town of Manchester;
(c) Bull Branch of Sunday River and tributaries in Grafton Township and Riley Township;
(d) Carrabassett River and tributaries in the Town of Carrabassett Valley, Freeman Township, the Town of Kingfield, Mount Abram Township and Salem Township;
(e) Cold Stream tributaries, including Tomhegan Stream, in Chase Stream Township, Johnson Mountain Township and West Forks Plantation;
(f) Enchanted Stream in Upper Enchanted Township and Lower Enchanted Township;
(g) Magalloway River and tributaries, including Little Magalloway River, in Bowmantown Township, Lincoln Plantation, Lynchtown Township, Magalloway Plantation, Oxbow Township, Parkertown Township and Parmachenee Township;
(h) Rapid River in the Town of Upton and Township C;
(i) Sheepscot River and tributaries, including the West Branch, in the Town of Alna, the Town of China, the Town of Freedom, the Town of Liberty, the Town of Montville, the Town of Palermo, the Town of Somerville, the Town of Whitefield and the Town of Windsor;
(j) South Bog Stream in Rangeley Plantation;
(k) Spencer Stream and Little Spencer Stream tributaries, including Kibby Stream in Kibby Township, Skinner Township, T.3, R.5 B.K.P. W.K.R., T.4, R.5 B.K.P. W.K.R., King and Bartlett Township and T.5, R.6 B.K.P. W.K.R.; and
(l) Togus Stream in the Town of Chelsea and the Town of Randolph.